Sample records for kda protein pvs25

  1. Evolution of the Transmission-Blocking Vaccine Candidates Pvs28 and Pvs25 in Plasmodium vivax: Geographic Differentiation and Evidence of Positive Selection

    PubMed Central

    Cornejo, Omar E.; Durrego, Ester; Stanley, Craig E.; Castillo, Andreína I.; Herrera, Sócrates; Escalante, Ananias A.

    2016-01-01

    Transmission-blocking (TB) vaccines are considered an important tool for malaria control and elimination. Among all the antigens characterized as TB vaccines against Plasmodium vivax, the ookinete surface proteins Pvs28 and Pvs25 are leading candidates. These proteins likely originated by a gene duplication event that took place before the radiation of the known Plasmodium species to primates. We report an evolutionary genetic analysis of a worldwide sample of pvs28 and pvs25 alleles. Our results show that both genes display low levels of genetic polymorphism when compared to the merozoite surface antigens AMA-1 and MSP-1; however, both ookinete antigens can be as polymorphic as other merozoite antigens such as MSP-8 and MSP-10. We found that parasite populations in Asia and the Americas are geographically differentiated with comparable levels of genetic diversity and specific amino acid replacements found only in the Americas. Furthermore, the observed variation was mainly accumulated in the EGF2- and EGF3-like domains for P. vivax in both proteins. This pattern was shared by other closely related non-human primate parasites such as Plasmodium cynomolgi, suggesting that it could be functionally important. In addition, examination with a suite of evolutionary genetic analyses indicated that the observed patterns are consistent with positive natural selection acting on Pvs28 and Pvs25 polymorphisms. The geographic pattern of genetic differentiation and the evidence for positive selection strongly suggest that the functional consequences of the observed polymorphism should be evaluated during development of TBVs that include Pvs25 and Pvs28. PMID:27347876

  2. Bombyx mori nucleopolyhedrovirus orf25 encodes a 30kDa late protein in the infection cycle.

    PubMed

    Wang, Haiyan; Chen, Keping; Guo, Zhongjian; Yao, Qin

    2008-02-01

    Bombyx mori nucleopolyhedrovirus (BmNPV) orf25 gene was characterized for the first time. The coding sequence of Bm25 was amplified and subcloned into the prokaryotic expression vector pGEX-4T-2 to produce glutathione S-transferase-tagged fusion protein in the BL21 (DE3) cells. The GST-Bm25 fusion protein was expressed efficiently after induction with IPTG. The purified fusion protein was used to immunize New Zealand white rabbits to prepare polyclonal antibody. Temporal expression analysis revealed a 30-kDa protein, which was detected beginning 24 hours post-infection using a polyclonal antibody against GST-Bm25 fusion protein. The transcript of Bm25 was detected by RT-PCR at 18-72 h p.i. In conclusion, the available data suggest that Bm25 encodes a 30kDa protein expressed in the late stage of infection cycle.

  3. Effects of porcine 25 kDa amelogenin and its proteolytic derivatives on bone sialoprotein expression.

    PubMed

    Nakayama, Y; Yang, L; Mezawa, M; Araki, S; Li, Z; Wang, Z; Sasaki, Y; Takai, H; Nakao, S; Fukae, M; Ogata, Y

    2010-10-01

    Amelogenins are hydrophobic proteins that are the major component of developing enamel. Enamel matrix derivative has been used for periodontal regeneration. Bone sialoprotein is an early phenotypic marker of osteoblast differentiation. In this study, we examined the ability of porcine amelogenins to regulate bone sialoprotein transcription. To determine the molecular basis of the transcriptional regulation of the bone sialoprotein gene by amelogenins, we conducted northern hybridization, transient transfection analyses and gel mobility shift assays using the osteoblast-like ROS 17/2.8 cells. Amelogenins (100 ng/mL) up-regulated bone sialoprotein mRNA at 3 h, with maximal mRNA expression occurring at 12 h (25 and 20 kDa) and 6 h (13 and 6 kDa). Amelogenins (100 ng/mL, 12 h) increased luciferase activities in pLUC3 (nucleotides -116 to +60), and 6 kDa amelogenin up-regulated pLUC4 (nucleotides -425 to +60) activity. The tyrosine kinase inhibitor inhibited amelogenin-induced luciferase activities, whereas the protein kinase A inhibitor abolished 25 kDa amelogenin-induced bone sialoprotein transcription. The effects of amelogenins were abrogated by 2-bp mutations in the fibroblast growth factor 2 response element (FRE). Gel-shift assays with radiolabeled FRE, homeodomain-protein binding site (HOX) and transforming growth factor-beta1 activation element (TAE) double-strand oligonucleotides revealed increased binding of nuclear proteins from amelogenin-stimulated ROS 17/2.8 cells at 3 h (25 and 13 kDa) and 6 h (20 and 6 kDa). These results demonstrate that porcine 25 kDa amelogenin and its proteolytic derivatives stimulate bone sialoprotein transcription by targeting FRE, HOX and TAE in the bone sialoprotein gene promoter, and that full-length amelogenin and amelogenin cleavage products are able to regulate bone sialoprotein transcription via different signaling pathways. (c) 2010 John Wiley & Sons A/S.

  4. The 29-kDa proteins phosphorylated ion thrombin-activated human platelets are forms of the estrogen receptor-related 27-kDa heat shock protein

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mendelsohn, M.E.; Yan Zhu; O'Neill, S.

    Thrombin plays a critical role in platelet activation, hemostasis, and thrombosis. Cellular activation by thrombin leads to the phosphorylation of multiple proteins, most of which are unidentified. The authors have characterized several 29-kDa proteins that are rapidly phosphorylated following exposure of intact human platelets to thrombin. A murine monoclonal antibody raised to an unidentified estrogen receptor-related 29-kDa protein selectively recognized these proteins as well as a more basic, unphosphorylated 27-kDa protein. Cellular activation by thrombin led to a marked shift in the proportion of protein from the 27-kDa unphosphorylated form to the 29-kDa phosphoprotein species. Using this antibody, they isolatedmore » and sequenced a human cDNA clone encoding a protein that was identical to the mammalian 27-kDa heat shock protein (HSP27), a protein of uncertain function that is known to be phosphorylated to several forms and to be transcriptionally induced by estrogen. The 29-kDa proteins were confirmed to be phosphorylated forms of HSP27 by immunoprecipitation studies. Thus, the estrogen receptor-related protein is HSP27, and the three major 20-kDa proteins phosphorylated in thrombin-activated platelets are forms of HSP27. These data suggest a role for HSP27 in the signal transduction events of platelet activation.« less

  5. Crystal structure of the 25 kDa subunit of human cleavage factor Im

    PubMed Central

    Coseno, Molly; Martin, Georges; Berger, Christopher; Gilmartin, Gregory; Keller, Walter; Doublié, Sylvie

    2008-01-01

    Cleavage factor Im is an essential component of the pre-messenger RNA 3′-end processing machinery in higher eukaryotes, participating in both the polyadenylation and cleavage steps. Cleavage factor Im is an oligomer composed of a small 25 kDa subunit (CF Im25) and a variable larger subunit of either 59, 68 or 72 kDa. The small subunit also interacts with RNA, poly(A) polymerase, and the nuclear poly(A)-binding protein. These protein–protein interactions are thought to be facilitated by the Nudix domain of CF Im25, a hydrolase motif with a characteristic α/β/α fold and a conserved catalytic sequence or Nudix box. We present here the crystal structures of human CF Im25 in its free and diadenosine tetraphosphate (Ap4A) bound forms at 1.85 and 1.80 Å, respectively. CF Im25 crystallizes as a dimer and presents the classical Nudix fold. Results from crystallographic and biochemical experiments suggest that CF Im25 makes use of its Nudix fold to bind but not hydrolyze ATP and Ap4A. The complex and apo protein structures provide insight into the active oligomeric state of CF Im and suggest a possible role of nucleotide binding in either the polyadenylation and/or cleavage steps of pre-messenger RNA 3′-end processing. PMID:18445629

  6. Crystal Structure of the 25 kDa Subunit of Human Cleavage Factor I{m}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Coseno,M.; Martin, G.; Berger, C.

    Cleavage factor Im is an essential component of the pre-messenger RNA 3'-end processing machinery in higher eukaryotes, participating in both the polyadenylation and cleavage steps. Cleavage factor Im is an oligomer composed of a small 25 kDa subunit (CF Im25) and a variable larger subunit of either 59, 68 or 72 kDa. The small subunit also interacts with RNA, poly(A) polymerase, and the nuclear poly(A)-binding protein. These protein-protein interactions are thought to be facilitated by the Nudix domain of CF Im25, a hydrolase motif with a characteristic {alpha}/{beta}/{alpha} fold and a conserved catalytic sequence or Nudix box. We present heremore » the crystal structures of human CF Im25 in its free and diadenosine tetraphosphate (Ap4A) bound forms at 1.85 and 1.80 Angstroms, respectively. CF Im25 crystallizes as a dimer and presents the classical Nudix fold. Results from crystallographic and biochemical experiments suggest that CF Im25 makes use of its Nudix fold to bind but not hydrolyze ATP and Ap4A. The complex and apo protein structures provide insight into the active oligomeric state of CF Im and suggest a possible role of nucleotide binding in either the polyadenylation and/or cleavage steps of pre-messenger RNA 3'-end processing.« less

  7. Effect of 14-kDa and 47-kDa protein molecules of age garlic extract on peritoneal macrophages.

    PubMed

    Daneshmandi, Saeed; Hajimoradi, Monire; Ahmadabad, Hasan Namdar; Hassan, Zuhair Mohammad; Roudbary, Maryam; Ghazanfari, Tooba

    2011-03-01

    Garlic (Allium sativum), traditionally being used as a spice worldwide, has different applications and is claimed to possess beneficial effects in several health ailments such as tumor and atherosclerosis. Garlic is also an immunomodulator and its different components are responsible for different properties. The present work aimed to assess the effect of protein fractions of garlic on peritoneal macrophages. 14-kDa and 47-kDa protein fractions of garlic were purified. Mice peritoneal macrophages were lavaged and cultured in a microtiter plate and exposed to different concentrations of garlic proteins. MTT assay was performed to evaluate the viability of macrophage. The amount of nitric oxide (NO) was detected in culture supernatants of macrophages by Griess reagent and furthermore, the cytotoxicity study of culture supernatants was carried out on WEHI-164 fibrosarcoma cell line as tumor necrosis factor-α bioassay. MTT assay results for both 14-kDa and 47-kDa protein fractions of stimulated macrophages were not significant (P > 0.05). Both 14-kDa and 47-kDa fractions significantly suppressed production of NO from macrophages (P = 0.007 and P = 0.003, respectively). Cytotoxicity of macrophages' supernatant on WEHI-164 fibrosarcoma cells was not affected by garlic protein fractions (P = 0.066 for 14-kDa and P = 0.085 for 47-kDa fractions). according to our finding, 14-kDa and 47-kDa fractions of aged garlic extract are able to suppress NO production from macrophages, which can be used as a biological advantage. These molecules had no cytotoxic effect on macrophages and do not increase tumoricidal property of macrophages.

  8. Rapid Prototyping in PVS

    NASA Technical Reports Server (NTRS)

    Munoz, Cesar A.; Butler, Ricky (Technical Monitor)

    2003-01-01

    PVSio is a conservative extension to the PVS prelude library that provides basic input/output capabilities to the PVS ground evaluator. It supports rapid prototyping in PVS by enhancing the specification language with built-in constructs for string manipulation, floating point arithmetic, and input/output operations.

  9. Phosphorylation of Tat-interactive protein 60 kDa by protein kinase C epsilon is important for its subcellular localisation.

    PubMed

    Sapountzi, Vasileia; Logan, Ian R; Nelson, Glyn; Cook, Susan; Robson, Craig N

    2008-01-01

    Tat-interactive protein 60 kDa is a nuclear acetyltransferase that both coactivates and corepresses transcription factors and has a definitive function in the DNA damage response. Here, we provide evidence that Tat-interactive protein 60 kDa is phosphorylated by protein kinase C epsilon. In vitro, protein kinase C epsilon phosphorylates Tat-interactive protein 60 kDa on at least two sites within the acetyltransferase domain. In whole cells, activation of protein kinase C increases the levels of phosphorylated Tat-interactive protein 60 kDa and the interaction of Tat-interactive protein 60 kDa with protein kinase C epsilon. A phosphomimetic mutant Tat-interactive protein 60 kDa has distinct subcellular localisation compared to the wild-type protein in whole cells. Taken together, these findings suggest that the protein kinase C epsilon phosphorylation sites on Tat-interactive protein 60 kDa are important for its subcellular localisation. Regulation of the subcellular localisation of Tat-interactive protein 60 kDa via phosphorylation provides a novel means of controlling Tat-interactive protein 60 kDa function.

  10. Abstract Datatypes in PVS

    NASA Technical Reports Server (NTRS)

    Owre, Sam; Shankar, Natarajan

    1997-01-01

    PVS (Prototype Verification System) is a general-purpose environment for developing specifications and proofs. This document deals primarily with the abstract datatype mechanism in PVS which generates theories containing axioms and definitions for a class of recursive datatypes. The concepts underlying the abstract datatype mechanism are illustrated using ordered binary trees as an example. Binary trees are described by a PVS abstract datatype that is parametric in its value type. The type of ordered binary trees is then presented as a subtype of binary trees where the ordering relation is also taken as a parameter. We define the operations of inserting an element into, and searching for an element in an ordered binary tree; the bulk of the report is devoted to PVS proofs of some useful properties of these operations. These proofs illustrate various approaches to proving properties of abstract datatype operations. They also describe the built-in capabilities of the PVS proof checker for simplifying abstract datatype expressions.

  11. Nano-LC FTICR tandem mass spectrometry for top-down proteomics: routine baseline unit mass resolution of whole cell lysate proteins up to 72 kDa.

    PubMed

    Tipton, Jeremiah D; Tran, John C; Catherman, Adam D; Ahlf, Dorothy R; Durbin, Kenneth R; Lee, Ji Eun; Kellie, John F; Kelleher, Neil L; Hendrickson, Christopher L; Marshall, Alan G

    2012-03-06

    Current high-throughput top-down proteomic platforms provide routine identification of proteins less than 25 kDa with 4-D separations. This short communication reports the application of technological developments over the past few years that improve protein identification and characterization for masses greater than 25 kDa. Advances in separation science have allowed increased numbers of proteins to be identified, especially by nanoliquid chromatography (nLC) prior to mass spectrometry (MS) analysis. Further, a goal of high-throughput top-down proteomics is to extend the mass range for routine nLC MS analysis up to 80 kDa because gene sequence analysis predicts that ~70% of the human proteome is transcribed to be less than 80 kDa. Normally, large proteins greater than 50 kDa are identified and characterized by top-down proteomics through fraction collection and direct infusion at relatively low throughput. Further, other MS-based techniques provide top-down protein characterization, however at low resolution for intact mass measurement. Here, we present analysis of standard (up to 78 kDa) and whole cell lysate proteins by Fourier transform ion cyclotron resonance mass spectrometry (nLC electrospray ionization (ESI) FTICR MS). The separation platform reduced the complexity of the protein matrix so that, at 14.5 T, proteins from whole cell lysate up to 72 kDa are baseline mass resolved on a nano-LC chromatographic time scale. Further, the results document routine identification of proteins at improved throughput based on accurate mass measurement (less than 10 ppm mass error) of precursor and fragment ions for proteins up to 50 kDa.

  12. Isolation and initial structural characterization of a 27 kDa protein from Zingiber officinale

    NASA Astrophysics Data System (ADS)

    Rasheed, Saima; Malik, Shoaib Ahmad; Falke, Sven; Arslan, Ali; Fazel, Ramin; Schlüter, Hartmut; Betzel, Christian; Choudhary, M. Iqbal

    2018-03-01

    Zingiber officinale Roscoe (Ginger) is a widely used traditional medicinal plant (for different ailments such as arthritis, constipation, and hypertension). This article describes the isolation and characterization of a so far unknown protein from ginger rhizomes applying ion exchange, affinity, size-exclusion chromatography, small angle X-ray scattering (SAXS), and mass spectrometry techniques. One-dimensional Coomassie-stained SDS-PAGE was performed under non-reducing conditions, showing one band corresponding to approx. 27 kDa. Dynamic light scattering (DLS) analysis of the protein solution revealed monodispersity and a monomeric state of the purified protein. Circular dichroism (CD) spectroscopy strongly indicated a β-sheet-rich protein, and disordered regions. MALDI-TOF-MS, and LC-MS/MS analysis resulted in the identification of 27.29 kDa protein, having 32.13% and 25.34% sequence coverage with Zingipain-1 and 2, respectively. The monomeric state and molecular weight were verified by small angle X-ray scattering (SAXS) studies. An elongated ab-initio model was calculated based on the scattering intensity distribution.

  13. Usefulness of 8 kDa protein of Fasciola hepatica in diagnosis of fascioliasis

    PubMed Central

    Kim, Kwangsig; Yang, Hyun Jong

    2003-01-01

    This study was designed to detect and evaluate an antigenicity of low molecular weight proteins of Fasciola hepatica in fascioliasis. Low molecular weight protein of F. hepatica was purified by ammonium sulfate precipitation and Sephacryl S-100 HR gel filtration. The protein obtained was estimated to be 8 kDa on 7.5-15% gradient sodium dodecyl sulfate gel electrophoresis. Immunoblotting studies showed that the 8 kDa protein reacted with human fascioliasis sera, but not other trematodiasis sera. This result suggests that the 8 kDa protein of F. hepatica is one of diagnostic antigens in human fascioliasis without cross-reaction with other human trematodiasis. PMID:12815325

  14. Developing User Strategies in PVS: A Tutorial

    NASA Technical Reports Server (NTRS)

    Archer, Myla; diVito, Ben; Munoz, Cesar

    2003-01-01

    This tutorial provides an overview of the PVS strategy language, and explains how to define new PVS strategies and load them into PVS, and how to create a strategy package. It then discusses several useful techniques that can be used in developing user strategies, and provides examples that illustrate many of these techniques.

  15. Analyzing Tabular and State-Transition Requirements Specifications in PVS

    NASA Technical Reports Server (NTRS)

    Owre, Sam; Rushby, John; Shankar, Natarajan

    1997-01-01

    We describe PVS's capabilities for representing tabular specifications of the kind advocated by Parnas and others, and show how PVS's Type Correctness Conditions (TCCs) are used to ensure certain well-formedness properties. We then show how these and other capabilities of PVS can be used to represent the AND/OR tables of Leveson and the Decision Tables of Sherry, and we demonstrate how PVS's TCCs can expose and help isolate errors in the latter. We extend this approach to represent the mode transition tables of the Software Cost Reduction (SCR) method in an attractive manner. We show how PVS can check these tables for well-formedness, and how PVS's model checking capabilities can be used to verify invariants and reachability properties of SCR requirements specifications, and inclusion relations between the behaviors of different specifications. These examples demonstrate how several capabilities of the PVS language and verification system can be used in combination to provide customized support for specific methodologies for documenting and analyzing requirements. Because they use only the standard capabilities of PVS, users can adapt and extend these customizations to suit their own needs. Those developing dedicated tools for individual methodologies may find these constructions in PVS helpful for prototyping purposes, or as a useful adjunct to a dedicated tool when the capabilities of a full theorem prover are required. The examples also illustrate the power and utility of an integrated general-purpose system such as PVS. For example, there was no need to adapt or extend the PVS model checker to make it work with SCR specifications described using the PVS TABLE construct: the model checker is applicable to any transition relation, independently of the PVS language constructs used in its definition.

  16. Identification of bovine sperm acrosomal proteins that interact with a 32-kDa acrosomal matrix protein.

    PubMed

    Nagdas, Subir K; Smith, Linda; Medina-Ortiz, Ilza; Hernandez-Encarnacion, Luisa; Raychoudhury, Samir

    2016-03-01

    Mammalian fertilization is accomplished by the interaction between sperm and egg. Previous studies from this laboratory have identified a stable acrosomal matrix assembly from the bovine sperm acrosome termed the outer acrosomal membrane-matrix complex (OMC). This stable matrix assembly exhibits precise binding activity for acrosin and N-acetylglucosaminidase. A highly purified OMC fraction comprises three major (54, 50, and 45 kDa) and several minor (38-19 kDa) polypeptides. The set of minor polypeptides (38-19 kDa) termed "OMCrpf polypeptides" is selectively solubilized by high-pH extraction (pH 10.5), while the three major polypeptides (55, 50, and 45 kDa) remain insoluble. Proteomic identification of the OMC32 polypeptide (32 kDa polypeptide isolated from high-pH soluble fraction of OMC) yielded two peptides that matched the NCBI database sequence of acrosin-binding protein. Anti-OMC32 recognized an antigenically related family of polypeptides (OMCrpf polypeptides) in the 38-19-kDa range with isoelectric points ranging between 4.0 and 5.1. Other than glycohydrolases, OMC32 may also be complexed to other acrosomal proteins. The present study was undertaken to identify and localize the OMC32 binding polypeptides and to elucidate the potential role of the acrosomal protein complex in sperm function. OMC32 affinity chromatography of a detergent-soluble fraction of bovine cauda sperm acrosome followed by mass spectrometry-based identification of bound proteins identified acrosin, lactadherin, SPACA3, and IZUMO1. Co-immunoprecipitation analysis also demonstrated the interaction of OMC32 with acrosin, lactadherin, SPACA3, and IZUMO1. Our immunofluorescence studies revealed the presence of SPACA3 and lactadherin over the apical segment, whereas IZUMO1 is localized over the equatorial segment of Triton X-100 permeabilized cauda sperm. Immunoblot analysis showed that a significant portion of SPACA3 was released after the lysophosphatidylcholine (LPC)-induced acrosome

  17. Translocation of an 89-kDa periplasmic protein is associated with Holospora infection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Iwatani, Koichi; Dohra, Hideo; Lang, B. Franz

    2005-12-02

    The symbiotic bacterium Holospora obtusa infects the macronucleus of the ciliate Paramecium caudatum. After ingestion by its host, an infectious form of Holospora with an electron-translucent tip passes through the host digestive vacuole and penetrates the macronuclear envelope with this tip. To investigate the underlying molecular mechanism of this process, we raised a monoclonal antibody against the tip-specific 89-kDa protein, sequenced this partially, and identified the corresponding complete gene. The deduced protein sequence carries two actin-binding motifs. Indirect immunofluorescence microscopy shows that during escape from the host digestive vacuole, the 89-kDa proteins translocates from the inside to the outside ofmore » the tip. When the bacterium invades the macronucleus, the 89-kDa protein is left behind at the entry point of the nuclear envelope. Transmission electron microscopy shows the formation of fine fibrous structures that co-localize with the antibody-labeled regions of the bacterium. Our findings suggest that the 89-kDa protein plays a role in Holospora's escape from the host digestive vacuole, the migration through the host cytoplasm, and the invasion into the macronucleus.« less

  18. Identification and Characterization of a 25 kDa Protein That Is Indispensable for the Efficient Saccharification of Eisenia bicyclis in the Digestive Fluid of Aplysia kurodai

    PubMed Central

    Tsuji, Akihiko; Kuwamura, Shuji; Shirai, Akihiro; Yuasa, Keizo

    2017-01-01

    The digestive fluid of the sea hare Aplysia kurodai can liberate approximately 2.5 mg of glucose from 10 mg of dried Eisenia bicyclis powder. Although laminaran, a major storage polysaccharide in E. bicyclis, is easily digested to glucose by the synergistic action of the 110 and 210 kDa A. kurodai β-glucosidases (BGLs), glucose is not liberated from E. bicyclis by direct incubation with these BGLs. To clarify this discrepancy, we searched for an Eisenia hydrolysis enhancing protein (EHEP) in the digestive fluid of A. kurodai. A novel 25 kDa protein that enhances E. bicyclis saccharification by β-glucosidases was purified to a homogeneous state from the digestive fluid of A. kurodai, and its cDNA was cloned from total cDNAs reverse-transcribed from hepatopancreas total RNA. The E. bicyclis extract strongly inhibited BGLs, suggesting some compound within this brown alga functioned as a feeding deterrent. However, when E. bicyclis was incubated with BGLs in the presence of EHEP, glucose production was markedly increased. As E. bicyclis is rich in phlorotannin, which are only found in brown algae, our study suggested that these compounds are the main BGL inhibitors in E. bicyclis extract. EHEP protects BGLs from phlorotannin inhibition by binding to phlorotannins and forming an insoluble complex with phloroglucinol and phlorotannins. These findings indicated that EHEP plays a key role in the saccharification of brown seaweeds containing phlorotannins in the digestive fluid of A. kurodai. This is the first report of EHEP as a phlorotannin-binding protein that protects BGLs from inhibition. PMID:28129373

  19. Isoform composition and stoichiometry of the approx. 90-kDa heat shock protein associated with glucocorticoid receptors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mendel, D.B.; Orti, E.

    1988-05-15

    The authors observed that the approx. 90-kDa non-steroid-binding component of nonactivated glucocorticoid receptors purified from WEHI-7 mouse thymoma cells (which has been identified as the approx. 90-kDa heat shock protein) consistently migrates as a doublet during polyacrylamide gel electrophoresis under denaturing and reducing conditions. It has recently been reported that murine Meth A cells contain a tumor-specific transplantation antigen (TSTA) which is related or identical to the approx. 90-kDa heat shock protein. The observation that TSTA and the approx. 90-kDa heat shock protein isolated from these cells exists as two isoforms of similar molecular mass and charge has suggested thatmore » the doublet observed is also due to the existence of two isoforms. They have therefore conducted this study to determine whether TSTA and the approx. 90-kDa component of glucocorticoid receptors are indeed related, to establish whether the receptor preferentially binds one isoform of the approx. 90-kDa heat shock protein, and to investigate the stoichiometry of the nonactivated receptor complex. They used the BuGr1 and AC88 monoclonal antibodies to purify, respectively, receptor-associated and free approx. 90-kDa heat shock protein from WEHI-7 cells grown for 48 h with (/sup 35/S)methionine to metabolically label proteins to steady state. The long-term metabolic labeling approach has also enabled them to directly determine that the purified non-activated glucocorticoid receptor contains a single steroid-binding protein and two approx. 90-kDa non-steroid-binding subunits. The consistency with which a approx. 1:2 stoichiometric ratio of steroid binding to approx. 90-kDa protein is observed supports the view that the approx. 90-kDa heat shock protein is a true component of nonactivated glucocorticoid-receptor complexes.« less

  20. Batch Proving and Proof Scripting in PVS

    NASA Technical Reports Server (NTRS)

    Munoz, Cesar A.

    2007-01-01

    The batch execution modes of PVS are powerful, but highly technical, features of the system that are mostly accessible to expert users. This paper presents a PVS tool, called ProofLite, that extends the theorem prover interface with a batch proving utility and a proof scripting notation. ProofLite enables a semi-literate proving style where specification and proof scripts reside in the same file. The goal of ProofLite is to provide batch proving and proof scripting capabilities to regular, non-expert, users of PVS.

  1. The Formal Semantics of PVS

    NASA Technical Reports Server (NTRS)

    Owre, Sam; Shankar, Natarajan

    1999-01-01

    A specification language is a medium for expressing what is computed rather than how it is computed. Specification languages share some features with programming languages but are also different in several important ways. For our purpose, a specification language is a logic within which the behavior of computational systems can be formalized. Although a specification can be used to simulate the behavior of such systems, we mainly use specifications to state and prove system properties with mechanical assistance. We present the formal semantics of the specification language of SRI's Prototype Verification System (PVS). This specification language is based on the simply typed lambda calculus. The novelty in PVS is that it contains very expressive language features whose static analysis (e.g., typechecking) requires the assistance of a theorem prover. The formal semantics illuminates several of the design considerations underlying PVS, the interaction between theorem proving and typechecking.

  2. Anti-inflammatory effect of garlic 14-kDa protein on LPS-stimulated-J774A.1 macrophages.

    PubMed

    Rabe, Shahrzad Zamani Taghizadeh; Ghazanfari, Tooba; Siadat, Zahra; Rastin, Maryam; Rabe, Shahin Zamani Taghizadeh; Mahmoudi, Mahmoud

    2015-04-01

    Garlic 14-kDa protein is purified from garlic (Allium sativum L.) which is used in traditional medicine and exerts various immunomodulatory activities. The present study investigated the suppressive effect of garlic 14-kDa protein on LPS-induced expression of pro-inflammatory mediators and underlying mechanism in inflammatory macrophages. J774A.1 macrophages were treated with 14-kDa protein (5-30 μg/ml) with/without LPS (1 μg/ml) and the production of inflammatory mediators such as prostaglandin E2 (PGE2), TNF-α, and IL-1β released were measured using ELISA. Nitric oxide (NO) production was determined using the Griess method. The anti-inflammatory activity of 14-kDa protein was examined by measuring inducible nitric oxide synthase and cyclooxygenase-2 proteins using western blot. The expression of nuclear NF-κB p65 subunit was assessed by western blot. Garlic 14-kDa protein significantly inhibited the excessive production of NO, PGE, TNF-α, and IL-1β in lipopolysaccharide (LPS)-activated J774A.1 macrophages in a concentration-related manner without cytotoxic effect. Western blot analysis demonstrated that garlic 14-kDa protein suppressed corresponding inducible NO synthase expression and activated cyclooxygenase-2 protein expression. The inhibitory effect was mediated partly by a reduction in the activity and expression of transcription factor NF-κB protein. Our results suggested, for the first time, garlic 14-kDa protein exhibits anti-inflammatory properties in macrophages possibly by suppressing the inflammatory mediators via the inhibition of transcription factor NF-κB signaling pathway. The traditional use of garlic as anti-inflammatory remedy could be ascribed partly to 14-kDa protein content. This protein might be a useful candidate for controlling inflammatory diseases and further investigations in vivo.

  3. Global genetic diversity of the Plasmodium vivax transmission-blocking vaccine candidate Pvs48/45.

    PubMed

    Vallejo, Andres F; Martinez, Nora L; Tobon, Alejandra; Alger, Jackeline; Lacerda, Marcus V; Kajava, Andrey V; Arévalo-Herrera, Myriam; Herrera, Sócrates

    2016-04-12

    Plasmodium vivax 48/45 protein is expressed on the surface of gametocytes/gametes and plays a key role in gamete fusion during fertilization. This protein was recently expressed in Escherichia coli host as a recombinant product that was highly immunogenic in mice and monkeys and induced antibodies with high transmission-blocking activity, suggesting its potential as a P. vivax transmission-blocking vaccine candidate. To determine sequence polymorphism of natural parasite isolates and its potential influence on the protein structure, all pvs48/45 sequences reported in databases from around the world as well as those from low-transmission settings of Latin America were compared. Plasmodium vivax parasite isolates from malaria-endemic regions of Colombia, Brazil and Honduras (n = 60) were used to sequence the Pvs48/45 gene, and compared to those previously reported to GenBank and PlasmoDB (n = 222). Pvs48/45 gene haplotypes were analysed to determine the functional significance of genetic variation in protein structure and vaccine potential. Nine non-synonymous substitutions (E35K, Y196H, H211N, K250N, D335Y, E353Q, A376T, K390T, K418R) and three synonymous substitutions (I73, T149, C156) that define seven different haplotypes were found among the 282 isolates from nine countries when compared with the Sal I reference sequence. Nucleotide diversity (π) was 0.00173 for worldwide samples (range 0.00033-0.00216), resulting in relatively high diversity in Myanmar and Colombia, and low diversity in Mexico, Peru and South Korea. The two most frequent substitutions (E353Q: 41.9 %, K250N: 39.5 %) were predicted to be located in antigenic regions without affecting putative B cell epitopes or the tertiary protein structure. There is limited sequence polymorphism in pvs48/45 with noted geographical clustering among Asian and American isolates. The low genetic diversity of the protein does not influence the predicted antigenicity or protein structure and, therefore

  4. Automated Real Proving in PVS via MetiTarski

    NASA Technical Reports Server (NTRS)

    Denman, William; Munoz, Cesar

    2014-01-01

    This paper reports the development of a proof strategy that integrates the MetiTarski theorem prover as a trusted external decision procedure into the PVS theorem prover. The strategy automatically discharges PVS sequents containing real-valued formulas, including transcendental and special functions, by translating the sequents into first order formulas and submitting them to MetiTarski. The new strategy is considerably faster and more powerful than other strategies for nonlinear arithmetic available to PVS.

  5. A Bitvectors Library for PVS

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.; Miner, Paul S.; Srivas, Mandayam K.; Greve, Dave A.; Miller, Steven P.

    1996-01-01

    This paper describes a bitvectors library that has been developed for PVS. The library defines a bitvector as a function from a subrange of the integers into (0,1). The library provides functions that interpret a bitvector as a natural number, as a 2's complement number, as a vector of logical values and as a 2's complement fraction. The library provides a concatenation operator and an extractor. Shift, extend and rotate operations are also, defined. Fundamental properties of each of these operations have been proved in PVS.

  6. Cardioprotective effects of 70-kDa heat shock protein in transgenic mice.

    PubMed

    Radford, N B; Fina, M; Benjamin, I J; Moreadith, R W; Graves, K H; Zhao, P; Gavva, S; Wiethoff, A; Sherry, A D; Malloy, C R; Williams, R S

    1996-03-19

    Heat shock proteins are proposed to limit injury resulting from diverse environmental stresses, but direct metabolic evidence for such a cytoprotective function in vertebrates has been largely limited to studies of cultured cells. We generated lines of transgenic mice to express human 70-kDa heat shock protein constitutively in the myocardium. Hearts isolated from these animals demonstrated enhanced recovery of high energy phosphate stores and correction of metabolic acidosis following brief periods of global ischemia sufficient to induce sustained abnormalities of these variables in hearts from nontransgenic littermates. These data demonstrate a direct cardioprotective effect of 70-kDa heat shock protein to enhance postischemic recovery of the intact heart.

  7. Carboxyl methylation of 21-23 kDa membrane proteins in intact neuroblastoma cells is increased with differentiation.

    PubMed

    Haklai, R; Kloog, Y

    1990-01-01

    Evidence is presented for specific enzymatic methylation of 21-23 kDa membrane proteins in intact neuroblastoma N1E 115 cells, which is increased in dimethylsulfoxide-induced differentiated cells. Methylation of these proteins has characteristics typical of enzymatic reactions in which base labile volatile methyl groups are incorporated into proteins, consistent with the formation of protein carboxyl methylesters. However, these methylesters of the 21-23 kDa proteins are relatively stable compared to other protein carboxyl methylesters. The 3-fold increase in methylated 21-23 kDa proteins in the differentiated cells suggest biological significance in differentiation of the cell membranes.

  8. Different effects of 25-kDa amelogenin on the proliferation, attachment and migration of various periodontal cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Xiting; Shu, Rong, E-mail: shurong123@hotmail.com; Liu, Dali

    Previous studies have assumed that amelogenin is responsible for the therapeutic effect of the enamel matrix derivative (EMD) in periodontal tissue healing and regeneration. However, it is difficult to confirm this hypothesis because both the EMD and the amelogenins are complex mixtures of multiple proteins. Further adding to the difficulties is the fact that periodontal tissue regeneration involves various types of cells and a sequence of associated cellular events including the attachment, migration and proliferation of various cells. In this study, we investigated the potential effect of a 25-kDa recombinant porcine amelogenin (rPAm) on primarily cultured periodontal ligament fibroblasts (PDLF),more » gingival fibroblasts (GF) and gingival epithelial cells (GEC). The cells were treated with 25-kDa recombinant porcine amelogenin at a concentration of 10 {mu}g/mL. We found that rPAm significantly promoted the proliferation and migration of PDLF, but not their adhesion. Similarly, the proliferation and adhesion of GF were significantly enhanced by treatment with rPAm, while migration was greatly inhibited. Interestingly, this recombinant protein inhibited the growth rate, cell adhesion and migration of GEC. These data suggest that rPAm may play an essential role in periodontal regeneration through the activation of periodontal fibroblasts and inhibition of the cellular behaviors of gingival epithelial cells.« less

  9. Cardioprotective effects of 70-kDa heat shock protein in transgenic mice.

    PubMed Central

    Radford, N B; Fina, M; Benjamin, I J; Moreadith, R W; Graves, K H; Zhao, P; Gavva, S; Wiethoff, A; Sherry, A D; Malloy, C R; Williams, R S

    1996-01-01

    Heat shock proteins are proposed to limit injury resulting from diverse environmental stresses, but direct metabolic evidence for such a cytoprotective function in vertebrates has been largely limited to studies of cultured cells. We generated lines of transgenic mice to express human 70-kDa heat shock protein constitutively in the myocardium. Hearts isolated from these animals demonstrated enhanced recovery of high energy phosphate stores and correction of metabolic acidosis following brief periods of global ischemia sufficient to induce sustained abnormalities of these variables in hearts from nontransgenic littermates. These data demonstrate a direct cardioprotective effect of 70-kDa heat shock protein to enhance postischemic recovery of the intact heart. Images Fig. 1 Fig. 3 PMID:8637874

  10. Ultratight crystal packing of a 10 kDa protein

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Trillo-Muyo, Sergio; Jasilionis, Andrius; Domagalski, Marcin J.

    2013-03-01

    The crystal structure of the C-terminal domain of a putative U32 peptidase from G. thermoleovorans is reported; it is one of the most tightly packed protein structures reported to date. While small organic molecules generally crystallize forming tightly packed lattices with little solvent content, proteins form air-sensitive high-solvent-content crystals. Here, the crystallization and full structure analysis of a novel recombinant 10 kDa protein corresponding to the C-terminal domain of a putative U32 peptidase are reported. The orthorhombic crystal contained only 24.5% solvent and is therefore among the most tightly packed protein lattices ever reported.

  11. Biochemical characterization of the 49 kDa penicillin-binding protein of Mycobacterium smegmatis.

    PubMed Central

    Mukherjee, T; Basu, D; Mahapatra, S; Goffin, C; van Beeumen, J; Basu, J

    1996-01-01

    The 49 kDa penicillin-binding protein (PBP) of Mycobacterium smegmatis catalyses the hydrolysis of the peptide or S-ester bond of carbonyl donors R1-CONH-CHR2-COX-CHR2-COO- (where X is NH or S). In the presence of a suitable amino acceptor, the reaction partitions between the transpeptidation and hydrolysis pathways, with the amino acceptor, behaving as a simple alternative nucleophile at the level of the acyl-enzyme. By virtue of its N-terminal sequence similarity, the 49 kDa PBP represents one of the class of monofunctional low-molecular-mass PBPs. An immunologically related protein of M(r) 52,000 is present in M. tuberculosis. The 49 kDa PBP is sensitive towards amoxycillin, imipenem, flomoxef and cefoxitin. PMID:8947487

  12. The 170-kDa glucose-regulated stress protein is an endoplasmic reticulum protein that binds immunoglobulin.

    PubMed Central

    Lin, H Y; Masso-Welch, P; Di, Y P; Cai, J W; Shen, J W; Subjeck, J R

    1993-01-01

    Anoxia, glucose starvation, calcium ionophore A23187, EDTA, glucosamine, and several other conditions that adversely affect the function of the endoplasmic reticulum (ER) induce the synthesis of the glucose-regulated class of stress proteins (GRPs). The primary GRPs induced by these stresses migrate at 78 and 94 kDa (GRP78 and GRP94). In addition, another protein of approximately 150-170 kDa (GRP170) has been previously observed and is coordinately induced with GRP78 and GRP94. To characterize this novel stress protein, we have prepared an antisera against purified GRP170. Immunofluorescence, Endoglycosidase H sensitivity, and protease resistance of this protein in microsomes indicates that GRP170 is an ER lumenal glycoprotein retained in a pre-Golgi compartment. Immunoprecipitation of GRP170 with our antibody coprecipitates the GRP78 (also referred to as the B cell immunoglobulin-binding protein) and GRP94 members of this stress protein family in Chinese hamster ovary cells under stress conditions. ATP depletion, by immunoprecipitation in the presence of apyrase, does not affect the interaction between GRP78 and GRP170 but results in the coprecipitation of an unidentified 60-kDa protein. In addition, GRP170 is found to be coprecipitated with immunoglobulin (Ig) in four different B cell hybridomas expressing surface IgM, cytoplasmic Ig light chain only, cytoplasmic Ig heavy chain only, or an antigen specific secreted IgG. In addition, in IgM surface expressing WEHI-231 B cells, anti-IgM coprecipitates GRP78, GRP94, as well as GRP170; antibodies against GRP170 and GRP94 reciprocally coprecipitate GRP94/GRP170 as well as GRP78. Results suggest that this 170-kDa GRP is a retained ER lumenal glycoprotein that is constitutively present and that may play a role in immunoglobulin folding and assembly in conjunction or consecutively with GRP78 and GRP94. Images PMID:8305733

  13. The analysis Arabidopsis thaliana overexpressing a 14kDa self-folding protein [abstract

    USDA-ARS?s Scientific Manuscript database

    A recent study in banana identified a 14kDa protein that has been hypothesized to function in regulating the nucleation and growth of the needle-shaped crystals of calcium oxalate that accumulate within the tissues of this plant. To gain further insight in to the functional role of this 14 kDa prote...

  14. The highly antigenic 53/25 kDa Taenia solium protein fraction with cathepsin-L like activity is present in the oncosphere/cysticercus and induces non-protective IgG antibodies in pigs

    PubMed Central

    Zimic, Mirko; Pajuelo, Mónica; Gilman, Robert H.; Gutiérrez, Andrés H.; Rueda, Luis D.; Flores, Myra; Chile, Nancy; Verástegui, Manuela; Gonzalez, Armando; García, Héctor H.; Sheen, Patricia

    2011-01-01

    Cathepsin L-like proteases are secreted by several parasites including Taenia solium. The mechanism used by T. solium oncospheres to degrade and penetrate the intestine and infect the host is incompletely understood. It is assumed that intestinal degradation is driven by the proteolytic activity of enzymes secreted by the oncosphere. Blocking the proteolytic activity by an antibody response would prevent the oncosphere penetration and further infection. Serine and cysteine proteases including chymotrypsin, trypsin, elastase, and cathepsin L, are secreted by T. solium and Taenia saginata oncospheres when cultured in vitro, being potential vaccine candidates. However, the purification of a sufficient quantity of proteases secreted by oncospheres to conduct a vaccine trial is costly and lengthy. A 53/25 kDa cathepsin L-like fraction partially purified from T. solium cyst fluid was described previously as an important antigen for immunodiagnostics. In this study we found that this antigen is present in the T. solium oncosphere and is also secreted by the cysticercus. This protein fraction was tested for its ability to protect pigs against an oral challenge with T. solium oncospheres in a vaccine trial. IgG antibodies against the 53/25 kDa cathepsin L-like protein fraction were elicited in the vaccinated animals but did not confer protection. PMID:22119017

  15. Identification of an abundant 56 kDa protein implicated in food allergy as granule-bound starch synthase

    USDA-ARS?s Scientific Manuscript database

    Rice, the staple food of South and East Asian counties, is considered to be hypoallergenic. However, several clinical studies have documented rice-induced allergy in sensitive patients. Rice proteins with molecular weights of 14-16 kDa, 26 kDa, 33 kDa and 56 kDa have been identified as allergens. Re...

  16. Defining the IEEE-854 floating-point standard in PVS

    NASA Technical Reports Server (NTRS)

    Miner, Paul S.

    1995-01-01

    A significant portion of the ANSI/IEEE-854 Standard for Radix-Independent Floating-Point Arithmetic is defined in PVS (Prototype Verification System). Since IEEE-854 is a generalization of the ANSI/IEEE-754 Standard for Binary Floating-Point Arithmetic, the definition of IEEE-854 in PVS also formally defines much of IEEE-754. This collection of PVS theories provides a basis for machine checked verification of floating-point systems. This formal definition illustrates that formal specification techniques are sufficiently advanced that is is reasonable to consider their use in the development of future standards.

  17. A novel Amoeba proteus 120 kDa actin-binding protein with only 1 filamin repeat and a coiled-coil region.

    PubMed

    Sobczak, Magdalena; Kocik, Elzbieta; Redowicz, Maria Jolanta

    2007-02-01

    A novel 120 kDa actin-binding protein (ApABP-F1) was found in Amoeba proteus. It was distributed throughout the cytoplasm, mainly in the subplasma membrane and perinuclear-nuclear areas, enriched in actin. The full-length cDNA of ApABP consisted of 2672 nucleotides with an open reading frame of 878 amino acids, giving a ~95 kDa protein with a theoretical pI value of 5.11. It had a novel domain organization pattern: the N terminus (residues 1-104) contained 1 calponin-homology (CH) domain, followed by only 1 region that was homologous to the filamin repeat (FR, residues 209-324), and a central region (residues 344-577) exhibiting a very high probability of coiled-coil formation, probably engaged in the observed protein dimerization. A phylogenetic tree constructed for CH domains from 25 various proteins revealed that the CH domain of ApABP was most related to that of the hypothetical mouse KIAA0903-like protein, whereas not much relationship to either filamins or the gelation factor (ABP-120) of Dictyostelium discoideum and Entamoeba histolytica was found.

  18. Evaluation of the immunomodulatory effect of the 14 kDa protein isolated from aged garlic extract on dendritic cells.

    PubMed

    Ahmadabad, Hasan Namdar; Hassan, Zuhair Mohammad; Safari, Elahe; Bozorgmehr, Mahmood; Ghazanfari, Tooba; Moazzeni, Seyed Mohammad

    2011-01-01

    Garlic is used all over the world for treatment of different diseases. A wide range of biological activities of garlic has been verified in vitro and in vivo. One of major proteins of garlic which has been isolated and purified is the 14 kDa protein. This protein has been shown to have immunomodulatory effects. In this study, the effect of the 14 kDa protein isolated from aged garlic extract (AGE) was investigated on maturation and immunomodulatory activity of dendritic cells (DC). Proteins were purified from AGE by biochemical method; the semi-purified 14 kDa protein was run on gel filtration Sephadex G50 and its purity was checked by SDS-PAGE. DC were isolated from spleen of BALB/c mice by Nycodenz centrifugation and their adhesiveness to plastic dish. 14 kDa protein from AGE was added to overnight culture of DC medium and the expression percentage of CD40, CD86, and MHC-II was evaluated by flowcytometric analysis. Also, proliferation of T-cells was measured by allogenic mixed lymphocyte reaction (MLR) test. The purified 14 kDa protein isolated from AGE increased the expression of CD40 molecule on DC, but it did not influence CD86 and MHCII molecules. Furthermore, no significant differences were noticed in the pulsed-DC with 14 kDa protein and non-pulsed DC on the MLR. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. A relevant IgE-reactive 28kDa protein identified from Salsola kali pollen extract by proteomics is a natural degradation product of an integral 47kDa polygalaturonase.

    PubMed

    Mas, Salvador; Oeo-Santos, Carmen; Cuesta-Herranz, Javier; Díaz-Perales, Araceli; Colás, Carlos; Fernández, Javier; Barber, Domingo; Rodríguez, Rosalía; de Los Ríos, Vivian; Barderas, Rodrigo; Villalba, Mayte

    2017-08-01

    A highly prevalent IgE-binding protein band of 28kDa is observed when Salsola kali pollen extract is incubated with individual sera from Amaranthaceae pollen sensitized patients. By an immunoproteomic analysis of S. kali pollen extract, we identified this protein band as an allergenic polygalacturonase enzyme. The allergen, named Sal k 6, exhibits a pI of 7.14 and a molecular mass of 39,554.2Da. It presents similarities to Platanaceae, Poaceae, and Cupressaceae allergenic polygalacturonases. cDNA-encoding sequence was subcloned into the pET41b vector and produced in bacteria as a His-tag fusion recombinant protein. The far-UV CD spectrum determined that rSal k 6 was folded. Immunostaining of the S. kali pollen protein extract with a rSal k 6-specific pAb and LC-MS/MS proteomic analyses confirmed the co-existence of the 28kDa band together with an allergenic band of about 47kDa in the pollen extract. Therefore, the 28kDa was assigned as a natural degradation product of the 47kDa integral polygalacturonase. The IgE-binding inhibition to S. kali pollen extract using rSal k 6 as inhibitor showed that signals directed to both protein bands of 28 and 47kDa were completely abrogated. The average prevalence of rSal k 6 among the three populations analyzed was 30%, with values correlating well with the levels of grains/m 3 of Amaranthaceae pollen. Sal k 6 shares IgE epitopes with Oleaceae members (Fraxinus excelsior, Olea europaea and Syringa vulgaris), with IgE-inhibition values ranging from 20% to 60%, respectively. No IgE-inhibition was observed with plant-derived food extracts. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Identification of a 27.8 kDa protein from flounder gill cells involved in lymphocystis disease virus binding and infection.

    PubMed

    Wang, Mu; Sheng, Xiu-Zhen; Xing, Jing; Tang, Xiao-Qian; Zhan, Wen-Bin

    2011-03-16

    In vitro, lymphocystis disease virus (LCDV) infection of flounder gill (FG) cell cultures causes obvious cytopathic effect (CPE). We describe attempts to isolate and characterize the LCDV-binding molecule(s) on the plasma membrane of FG cells that were responsible for virus entry. The results showed that the co-immunoprecipitation assay detected a 27.8 kDa molecule from FG cells that bound to LCDV. In a blocking ELISA, pre-incubation of FG cell membrane proteins with the specific antiserum developed against the 27.8 kDa protein could block LCDV binding. Similarly, antiserum against 27.8 kDa protein could also inhibit LCDV infection of FG cells in vitro. Mass spectrometric analysis established that the 27.8 kDa protein and beta-actin had a strong association. These results strongly supported the possibility that the 27.8 kDa protein was the putative receptor specific for LCDV infection of FG cells.

  1. A High-Level Formalization of Floating-Point Number in PVS

    NASA Technical Reports Server (NTRS)

    Boldo, Sylvie; Munoz, Cesar

    2006-01-01

    We develop a formalization of floating-point numbers in PVS based on a well-known formalization in Coq. We first describe the definitions of all the needed notions, e.g., floating-point number, format, rounding modes, etc.; then, we present an application to polynomial evaluation for elementary function evaluation. The application already existed in Coq, but our formalization shows a clear improvement in the quality of the result due to the automation provided by PVS. We finally integrate our formalization into a PVS hardware-level formalization of the IEEE-854 standard previously developed at NASA.

  2. A PVS Prover Strategy Package for Common Manipulations

    NASA Technical Reports Server (NTRS)

    DiVito, Ben L.

    2002-01-01

    Sequent manipulations for an interactive prover such as PVS can often be labor intensive. We describe an approach to tactic-based proving for improved interactive deduction in specialized domains. An experimental package of strategies (tactics) and support functions has been developed for PVS to reduce the tedium of arithmetic manipulation. Included are strategies aimed at algebraic simplification of real-valued expressions as well as term-access techniques applicable in arbitrary settings. The approach is general enough to serve in other mathematical domains and for provers other than PVS. This report presents the full set of arithmetic strategies and discusses how they are invoked within the prover. Included is a description of the extended expression notation for accessing terms as well as a substitution technique provided for higher-order strategies. Several sample proofs are displayed in full to show how the strategies might be used in practice.

  3. Sequencing Larger Intact Proteins (30-70 kDa) with Activated Ion Electron Transfer Dissociation

    NASA Astrophysics Data System (ADS)

    Riley, Nicholas M.; Westphall, Michael S.; Coon, Joshua J.

    2018-01-01

    The analysis of intact proteins via mass spectrometry can offer several benefits to proteome characterization, although the majority of top-down experiments focus on proteoforms in a relatively low mass range (<30 kDa). Recent studies have focused on improving the analysis of larger intact proteins (up to 75 kDa), but they have also highlighted several challenges to be addressed. One major hurdle is the efficient dissociation of larger protein ions, which often to do not yield extensive fragmentation via conventional tandem MS methods. Here we describe the first application of activated ion electron transfer dissociation (AI-ETD) to proteins in the 30-70 kDa range. AI-ETD leverages infrared photo-activation concurrent to ETD reactions to improve sequence-informative product ion generation. This method generates more product ions and greater sequence coverage than conventional ETD, higher-energy collisional dissociation (HCD), and ETD combined with supplemental HCD activation (EThcD). Importantly, AI-ETD provides the most thorough protein characterization for every precursor ion charge state investigated in this study, making it suitable as a universal fragmentation method in top-down experiments. Additionally, we highlight several acquisition strategies that can benefit characterization of larger proteins with AI-ETD, including combination of spectra from multiple ETD reaction times for a given precursor ion, multiple spectral acquisitions of the same precursor ion, and combination of spectra from two different dissociation methods (e.g., AI-ETD and HCD). In all, AI-ETD shows great promise as a method for dissociating larger intact protein ions as top-down proteomics continues to advance into larger mass ranges. [Figure not available: see fulltext.

  4. A PVS Graph Theory Library

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.; Sjogren, Jon A.

    1998-01-01

    This paper documents the NASA Langley PVS graph theory library. The library provides fundamental definitions for graphs, subgraphs, walks, paths, subgraphs generated by walks, trees, cycles, degree, separating sets, and four notions of connectedness. Theorems provided include Ramsey's and Menger's and the equivalence of all four notions of connectedness.

  5. High expression of 23 kDa protein of augmenter of liver regeneration (ALR) in human hepatocellular carcinoma

    PubMed Central

    Yu, Hai-Ying; Zhu, Man-Hua; Xiang, Dai-Rong; Li, Jun; Sheng, Ji-Fang

    2014-01-01

    Background Augmenter of liver regeneration (ALR) is an important polypeptide that participates in the process of liver regeneration. Two forms of ALR proteins are expressed in hepatocytes. Previous data have shown that ALR is essential for cell survival and has potential antimetastatic properties in hepatocellular carcinoma (HCC). Aims The study aimed to evaluate the expression levels of two forms of ALR proteins in HCC and their possible significance in HCC development. Methods Balb/c mouse monoclonal antibody against ALR protein was prepared in order to detect the ALR protein in HCC by Western blotting and immunohistochemistry. ALR mRNA expression levels were measured by real-time polymerase chain reaction in HCC tissues and compared to paracancerous liver tissues in 22 HCC patients. Results ALR mRNA expression in HCC liver tissues (1.51×106 copies/μL) was higher than in paracancerous tissues (1.04×104 copies/μL). ALR protein expression was also enhanced in HCC liver tissues. The enhanced ALR protein was shown to be 23 kDa by Western blotting. Immunohistochemical analysis showed that the 23 kDa ALR protein mainly existed in the hepatocyte cytosol. Conclusion The 23 kDa ALR protein was highly expressed in HCC and may play an important role in hepatocarcinogenesis. PMID:24940072

  6. Using human sera to identify a 52-kDa exoantigen of Penicillium chrysogenum and implications of polyphasic taxonomy of anamorphic ascomycetes in the study of antigenic proteins.

    PubMed

    Wilson, Aaron M; Luo, Wen; Miller, J David

    2009-11-01

    We are interested in isolating and identifying antigenic fungal proteins from species that grow on damp building materials. The indoor clade of Penicillium chrysogenum, the so-called Fleming clade, is the most common species of Penicillium on moldy building materials. We have identified a 52-kDa marker protein for the indoor clade of P. chrysogenum not present in a taxonomically diverse selection of fungi. It is found in high concentrations in protein extracted from the fungus grown on paper-faced gypsum wallboard. During this process, we illuminated the variability in response to patient sera and of strains of the fungus collected over a wide geographic area. From a collection of sera from all over the USA, 25 of the 48 patients reacted to the 52-kDa protein from this prescreened collection of sera. Most strain/antibody combinations had proportionate ELISA response associated with the presence of the target. However, approximately 25% of the strain/patient serum combinations included people who responded to many common allergens from the Penicillia. All the P. chrysogenum strains tested produced the target protein. However, there was considerable variability in patient IgG response to 32-, 30-, and 18-kDa antigens and in their production by the various clade 4 strains. The target protein was not found in spores or culture extracts of a wide selection of relevant fungi. It appears that the previous studies have been conducted on strains of the fungus from the three clades not those associated with the built environment.

  7. The 21.5-kDa isoform of myelin basic protein has a non-traditional PY-nuclear-localization signal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith, Graham S.T.; Seymour, Lauren V.; Boggs, Joan M.

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer Full-length 21.5-kDa MBP isoform is translocated to the nucleus. Black-Right-Pointing-Pointer We hypothesized that the exon-II-encoded sequence contained the NLS. Black-Right-Pointing-Pointer We mutated this sequence in RFP-tagged constructs and transfected N19-cells. Black-Right-Pointing-Pointer Abolition of two key positively-charged residues resulted in loss of nuclear-trafficking. Black-Right-Pointing-Pointer The 21.5-kDa isoform of classic MBP contains a non-traditional PY-NLS. -- Abstract: The predominant 18.5-kDa classic myelin basic protein (MBP) is mainly responsible for compaction of the myelin sheath in the central nervous system, but is multifunctional, having numerous interactions with Ca{sup 2+}-calmodulin, actin, tubulin, and SH3-domains, and can tether these proteins to a lipidmore » membrane in vitro. The full-length 21.5-kDa MBP isoform has an additional 26 residues encoded by exon-II of the classic gene, which causes it to be trafficked to the nucleus of oligodendrocytes (OLGs). We have performed site-directed mutagenesis of selected residues within this segment in red fluorescent protein (RFP)-tagged constructs, which were then transfected into the immortalized N19-OLG cell line to view protein localization using epifluorescence microscopy. We found that 21.5-kDa MBP contains two non-traditional PY-nuclear-localization signals, and that arginine and lysine residues within these motifs were involved in subcellular trafficking of this protein to the nucleus, where it may have functional roles during myelinogenesis.« less

  8. Theory Interpretations in PVS

    NASA Technical Reports Server (NTRS)

    Owre, Sam; Shankar, Natarajan; Butler, Ricky W. (Technical Monitor)

    2001-01-01

    The purpose of this task was to provide a mechanism for theory interpretations in a prototype verification system (PVS) so that it is possible to demonstrate the consistency of a theory by exhibiting an interpretation that validates the axioms. The mechanization makes it possible to show that one collection of theories is correctly interpreted by another collection of theories under a user-specified interpretation for the uninterpreted types and constants. A theory instance is generated and imported, while the axiom instances are generated as proof obligations to ensure that the interpretation is valid. Interpretations can be used to show that an implementation is a correct refinement of a specification, that an axiomatically defined specification is consistent, or that a axiomatically defined specification captures its intended models. In addition, the theory parameter mechanism has been extended with a notion of theory as parameter so that a theory instance can be given as an actual parameter to an imported theory. Theory interpretations can thus be used to refine an abstract specification or to demonstrate the consistency of an axiomatic theory. In this report we describe the mechanism in detail. This extension is a part of PVS version 3.0, which will be publicly released in mid-2001.

  9. cDNA, genomic sequence cloning and overexpression of ribosomal protein S25 gene (RPS25) from the Giant Panda.

    PubMed

    Hao, Yan-Zhe; Hou, Wan-Ru; Hou, Yi-Ling; Du, Yu-Jie; Zhang, Tian; Peng, Zheng-Song

    2009-11-01

    RPS25 is a component of the 40S small ribosomal subunit encoded by RPS25 gene, which is specific to eukaryotes. Studies in reference to RPS25 gene from animals were handful. The Giant Panda (Ailuropoda melanoleuca), known as a "living fossil", are increasingly concerned by the world community. Studies on RPS25 of the Giant Panda could provide scientific data for inquiring into the hereditary traits of the gene and formulating the protective strategy for the Giant Panda. The cDNA of the RPS25 cloned from Giant Panda is 436 bp in size, containing an open reading frame of 378 bp encoding 125 amino acids. The length of the genomic sequence is 1,992 bp, which was found to possess four exons and three introns. Alignment analysis indicated that the nucleotide sequence of the coding sequence shows a high homology to those of Homo sapiens, Bos taurus, Mus musculus and Rattus norvegicus as determined by Blast analysis, 92.6, 94.4, 89.2 and 91.5%, respectively. Primary structure analysis revealed that the molecular weight of the putative RPS25 protein is 13.7421 kDa with a theoretical pI 10.12. Topology prediction showed there is one N-glycosylation site, one cAMP and cGMP-dependent protein kinase phosphorylation site, two Protein kinase C phosphorylation sites and one Tyrosine kinase phosphorylation site in the RPS25 protein of the Giant Panda. The RPS25 gene was overexpressed in E. coli BL21 and Western Blotting of the RPS25 protein was also done. The results indicated that the RPS25 gene can be really expressed in E. coli and the RPS25 protein fusioned with the N-terminally his-tagged form gave rise to the accumulation of an expected 17.4 kDa polypeptide. The cDNA and the genomic sequence of RPS25 were cloned successfully for the first time from the Giant Panda using RT-PCR technology and Touchdown-PCR, respectively, which were both sequenced and analyzed preliminarily; then the cDNA of the RPS25 gene was overexpressed in E. coli BL21 and immunoblotted, which is the first

  10. NADH:ubiquinone oxidoreductase from bovine heart mitochondria. cDNA sequences of the import precursors of the nuclear-encoded 39 kDa and 42 kDa subunits.

    PubMed Central

    Fearnley, I M; Finel, M; Skehel, J M; Walker, J E

    1991-01-01

    The 39 kDa and 42 kDa subunits of NADH:ubiquinone oxidoreductase from bovine heart mitochondria are nuclear-coded components of the hydrophobic protein fraction of the enzyme. Their amino acid sequences have been deduced from the sequences of overlapping cDNA clones. These clones were amplified from total bovine heart cDNA by means of the polymerase chain reaction, with the use of complex mixtures of oligonucleotide primers based upon fragments of protein sequence determined at the N-terminals of the proteins and at internal sites. The protein sequences of the 39 kDa and 42 kDa subunits are 345 and 320 amino acid residues long respectively, and their calculated molecular masses are 39,115 Da and 36,693 Da. Both proteins are predominantly hydrophilic, but each contains one or two hydrophobic segments that could possibly be folded into transmembrane alpha-helices. The bovine 39 kDa protein sequence is related to that of a 40 kDa subunit from complex I from Neurospora crassa mitochondria; otherwise, it is not related significantly to any known sequence, including redox proteins and two polypeptides involved in import of proteins into mitochondria, known as the mitochondrial processing peptidase and the processing-enhancing protein. Therefore the functions of the 39 kDa and 42 kDa subunits of complex I are unknown. The mitochondrial gene product, ND4, a hydrophobic component of complex I with an apparent molecular mass of about 39 kDa, has been identified in preparations of the enzyme. This subunit stains faintly with Coomassie Blue dye, and in many gel systems it is not resolved from the nuclearcoded 36 kDa subunit. Images Fig. 1. PMID:1832859

  11. The glyoxysomal and plastid molecular chaperones (70-kDa heat shock protein) of watermelon cotyledons are encoded by a single gene

    PubMed Central

    Wimmer, Bernhard; Lottspeich, Friedrich; van der Klei, Ida; Veenhuis, Marten; Gietl, Christine

    1997-01-01

    The monoclonal a-70-kDa heat shock protein (hsp70) antibody recognizes in crude extracts from watermelon (Citrullus vulgaris) cotyledons two hsps with molecular masses of 70 and 72 kDa. Immunocytochemistry on watermelon cotyledon tissue and on isolated glyoxysomes identified hsp70s in the matrix of glyoxysomes and plastids. Affinity purification and partial amino acid determination revealed the 70-kDa protein to share high sequence identity with cytosolic hsp70s from a number of plant species, while the 72 kDa protein was very similar to plastid hsp70s from pea and cucumber. A full-length cDNA clone encoding the 72-kDa hsp70 was isolated and identified two start methionines in frame within the N-terminal presequence leading either to an N-terminal extension of 67 amino acids or to a shorter one of 47 amino acids. The longer presequence was necessary and sufficient to target a reporter protein into watermelon proplastids in vitro. The shorter extension starting from the second methionine within the long version harbored a consensus peroxisomal targeting signal (RT-X5-KL) that directed in vivo a reporter protein into peroxisomes of the yeast Hansenula polymorpha. Peroxisomal targeting was however prevented, when the 67-residue presequence was fused to the reporter protein, indicating that the peroxisomal targeting signal 2 information is hidden in this context. We propose that the 72-kDa hsp70 is encoded by a single gene, but targeted alternatively into two organelles by the modulated use of its presequence. PMID:9391076

  12. Monoclonal antibodies against 27.8 kDa protein receptor efficiently block lymphocystis disease virus infection in flounder Paralichthys olivaceus gill cells.

    PubMed

    Sheng, Xiu-Zhen; Wang, Mu; Xing, Jing; Zhan, Wen-Bin

    2012-08-13

    In previous research using co-immunoprecipitation, a 27.8 kDa protein in flounder Paralichthys olivaceus gill (FG) cells was found to bind lymphocystis disease virus (LCDV). In this paper, 13 hybridomas secreting monoclonal antibodies (MAbs) against the 27.8 kDa protein were obtained, and 2 MAbs designated as 2G11 and 3D9 were cloned by limiting dilution. Analyzed by indirect enzyme-linked immunosorbent assay (ELISA) and western blotting, the MAbs specifically reacted with the 27.8 kDa protein of FG cells. Confocal fluorescence microscopy and immunogold electron microscopy (IEM) provided evidence that the epitopes recognized by these MAbs were located primarily on the cell membrane and occasionally in the cytoplasm near the cell membrane of FG cells. The MAbs could block LCDV binding after MAbs were pre-incubated with isolated membrane proteins of FG cells in a blocking ELISA, and MAbs also could inhibit LCDV infection of FG cells in culture. Moreover, several target tissues of LCDV in flounder, including gill, stomach, intestine and liver, displayed the presence of the LCDV receptor-27.8 kDa. These results strongly supported the possibility that the 27.8 kDa protein is the putative receptor specific for LCDV infection of FG cells in flounder.

  13. An elementary tutorial on formal specification and verification using PVS

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.

    1993-01-01

    A tutorial on the development of a formal specification and its verification using the Prototype Verification System (PVS) is presented. The tutorial presents the formal specification and verification techniques by way of specific example - an airline reservation system. The airline reservation system is modeled as a simple state machine with two basic operations. These operations are shown to preserve a state invariant using the theorem proving capabilities of PVS. The technique of validating a specification via 'putative theorem proving' is also discussed and illustrated in detail. This paper is intended for the novice and assumes only some of the basic concepts of logic. A complete description of user inputs and the PVS output is provided and thus it can be effectively used while one is sitting at a computer terminal.

  14. Platelet cytosolic 44-kDa protein is a substrate of cholera toxin-induced ADP-ribosylation and is not recognized by antisera against the. alpha. subunit of the stimulatory guanine nucleotide-binding regulatory protein

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Molina Y Vedia, L.M.; Reep, B.R.; Lapetina, E.G.

    1988-08-01

    ADP-ribosylation induced by cholera toxin and pertussis toxin was studied in particulate and cytosolic fractions of human platelets. Platelets were disrupted by a cycle of freezing and thawing in the presence of a hyposmotic buffer containing protease inhibitors. In both fractions, the A subunit of cholera toxin ADP-ribosylates two proteins with molecular masses of 42 and 44 kDa, whereas pertussis toxin ADP-ribosylates a 41-kDa polypeptide. Two antisera against the {alpha} subunit of the stimulatory guanine nucleotide-binding regulatory protein recognize only the 42-kDa polypeptide. Cholera toxin-induced ADP-ribosylation of the 42- and 44-kDa proteins is reduced by pretreatment of platelets with iloprost,more » a prostacyclin analog. The 44-kDa protein, which is substrate of cholera toxin, could be extracted completely from the membrane and recovered in the cytosolic fraction when the cells were disrupted by Dounce homogenization and the pellet was extensively washed. A 44-kDa protein can also be labeled with 8-azidoguanosine 5{prime}-({alpha}-{sup 32}P)triphosphate in the cytosol and membranes. These finding indicate that cholera and pertussis toxins produced covalent modifications of proteins present in particulate and cytosolic platelet fractions. Moreover, the 44-kDa protein might be an {alpha} subunit of a guanine nucleotide-binding regulatory protein that is not recognized by available antisera.« less

  15. A conserved 19-kDa Eimeria tenella antigen is a profilin-like protein.

    PubMed

    Fetterer, R H; Miska, K B; Jenkins, M C; Barfield, R C

    2004-12-01

    A wide range of recombinant proteins from Eimeria species have been reported to offer some degree of protection against infection and disease, but the specific biological function of these proteins is largely unknown. Previous studies have demonstrated a 19-kDa protein of unknown function designated SZ-1 in sporozoites and merozoites of Eimeria acervulina that can be used to confer partial protection against coccidiosis. Reverse transcriptase-polymerase chain reaction indicated that the gene for SZ-1 is expressed by all the asexual stages of Eimeria tenella. Rabbit antisera to recombinant SZ-1 recognized an approximately 19-kDa protein from extracts of E. tenella sporozoites, merozoites, sporulated oocysts, and oocysts in various stages of sporulation. Immunofluorescence antibody staining indicated specific staining of E. tenella sporozoites and merozoites. Staining was most intense in the cytoplasm of the posterior end of the parasite. The primary amino acid sequence of the gene for E. tenella SZ-1 deduced from the E. tenella genome indicated a conserved domain for the actin-regulatory protein profilin. A conserved binding site for poly-L-proline (PLP), characteristic of profilin was also observed. SZ-1 was separated from soluble extract of E. tenella proteins by affinity chromatography using a PLP ligand, confirming the ability of SZ-1 to bind PLP. SZ-1 also partially inhibited the polymerization of actin. The current results are consistent with the classification of SZ-1 as a profilin-related protein.

  16. Cryopreservation of in vitro grown nodal segments of Rauvolfia serpentina by PVS2 vitrification.

    PubMed

    Ray, Avik; Bhattacharya, Sabita

    2008-01-01

    This paper describes the cryopreservation by PVS2 vitrification of Rauvolfia serpentina (L.) Benth ex kurz, an important tropical medicinal plant. The effects of type and size of explants, sucrose preculture (duration and concentration) and vitrification treatment were tested. Preliminary experiments with PVS1, 2 and 3 produced shoot growth only for PVS2. When optimizing the PVS2 vitrification of nodal segments, those of 0.31 - 0.39 cm in size were better than other nodal sizes and or apices. Sucrose preculture had a positive role in survival and subsequent regrowth of the cryopreserved explants. Seven days on 0.5 M sucrose solution significantly improved the viability of nodal segments. PVS2 incubation for 45 minutes combined with a 7-day preculture gave the optimum result of 66 percent. Plantlets derived after cryopreservation resumed growth and regenerated normally.

  17. Formalization of the Integral Calculus in the PVS Theorem Prover

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.

    2004-01-01

    The PVS Theorem prover is a widely used formal verification tool used for the analysis of safety-critical systems. The PVS prover, though fully equipped to support deduction in a very general logic framework, namely higher-order logic, it must nevertheless, be augmented with the definitions and associated theorems for every branch of mathematics and Computer Science that is used in a verification. This is a formidable task, ultimately requiring the contributions of researchers and developers all over the world. This paper reports on the formalization of the integral calculus in the PVS theorem prover. All of the basic definitions and theorems covered in a first course on integral calculus have been completed.The theory and proofs were based on Rosenlicht's classic text on real analysis and follow the traditional epsilon-delta method. The goal of this work was to provide a practical set of PVS theories that could be used for verification of hybrid systems that arise in air traffic management systems and other aerospace applications. All of the basic linearity, integrability, boundedness, and continuity properties of the integral calculus were proved. The work culminated in the proof of the Fundamental Theorem Of Calculus. There is a brief discussion about why mechanically checked proofs are so much longer than standard mathematics textbook proofs.

  18. In vivo exposure to ozone produces an increase in a 72-kDa heat shock protein in guinea pigs.

    PubMed

    Su, W Y; Gordon, T

    1997-09-01

    Although several lines of evidence have suggested that oxidizing agents can induce heat shock proteins (HSPs) in vitro, little is known about the induction of HSPs during in vivo exposure to oxidants. Guinea pigs were exposed to ozone for 6 h and euthanized up to 72 h later. Proteins from lavage cells and lung tissue were characterized by immunoblotting with 72- and 73/72-kDa HSP monoclonal antibodies. Although 73-kDa HSP was expressed constituitively in lung tissue, it was not affected by ozone. In contrast, 72-kDa HSP was significantly increased in lavage cells and lung tissue of animals exposed to 0.4 and 0.66 parts/million of ozone. Both heat treatment and arsenite induced 72-kDa HSP in cultured alveolar macrophages. The increase in 72-kDa HSP in the lavage cell pellet peaked at 24 h after ozone, whereas the influx of polymorphonuclear leukocytes peaked at 4 h. Examination of the induction of HSPs by ozone may provide clues to the development of ozone tolerance in humans and animals.

  19. An introduction to requirements capture using PVS: Specification of a simple autopilot

    NASA Technical Reports Server (NTRS)

    Butler, Ricky W.

    1996-01-01

    This paper presents an introduction to capturing software requirements in the PVS formal language. The object of study is a simplified digital autopilot that was motivated in part by the mode control panel of NASA Langley's Boeing 737 research aircraft. The paper first presents the requirements for this autopilot in English and then steps the reader through a translation of these requirements into formal mathematics. Along the way deficiencies in the English specification are noted and repaired. Once completed, the formal PVS requirement is analyzed using the PVS theorem prover and shown to maintain an invariant over its state space.

  20. Tula hantavirus L protein is a 250 kDa perinuclear membrane-associated protein.

    PubMed

    Kukkonen, Sami K J; Vaheri, Antti; Plyusnin, Alexander

    2004-05-01

    The complete open reading frame of Tula hantavirus (TULV) L RNA was cloned in three parts. The middle third (nt 2191-4344) could be expressed in E. coli and was used to immunize rabbits. The resultant antiserum was then used to immunoblot concentrated TULV and infected Vero E6 cells. The L protein of a hantavirus was detected, for the first time, in infected cells and was found to be expressed as a single protein with an apparent molecular mass of 250 kDa in both virions and infected cells. Using the antiserum, the expression level of the L protein was followed and image analysis of immunoblots indicated that there were 10(4) copies per cell at the peak level of expression. The antiserum was also used to detect the L protein in cell fractionation studies. In cells infected with TULV and cells expressing recombinant L, the protein pelleted with the microsomal membrane fraction. The membrane association was confirmed with membrane flotation assays. To visualize L protein localization in cells, a fusion protein of L and enhanced green fluorescent protein, L-EGFP, was expressed in Vero E6 cells with a plasmid-driven T7 expression system. L-EGFP localized in the perinuclear region where it had partial co-localization with the Golgi matrix protein GM130 and the TULV nucleocapsid protein.

  1. pvsR: An Open Source Interface to Big Data on the American Political Sphere.

    PubMed

    Matter, Ulrich; Stutzer, Alois

    2015-01-01

    Digital data from the political sphere is abundant, omnipresent, and more and more directly accessible through the Internet. Project Vote Smart (PVS) is a prominent example of this big public data and covers various aspects of U.S. politics in astonishing detail. Despite the vast potential of PVS' data for political science, economics, and sociology, it is hardly used in empirical research. The systematic compilation of semi-structured data can be complicated and time consuming as the data format is not designed for conventional scientific research. This paper presents a new tool that makes the data easily accessible to a broad scientific community. We provide the software called pvsR as an add-on to the R programming environment for statistical computing. This open source interface (OSI) serves as a direct link between a statistical analysis and the large PVS database. The free and open code is expected to substantially reduce the cost of research with PVS' new big public data in a vast variety of possible applications. We discuss its advantages vis-à-vis traditional methods of data generation as well as already existing interfaces. The validity of the library is documented based on an illustration involving female representation in local politics. In addition, pvsR facilitates the replication of research with PVS data at low costs, including the pre-processing of data. Similar OSIs are recommended for other big public databases.

  2. A Prototype Embedding of Bluespec System Verilog in the PVS Theorem Prover

    NASA Technical Reports Server (NTRS)

    Richards, Dominic; Lester, David

    2010-01-01

    Bluespec SystemVerilog (BSV) is a Hardware Description Language based on the guarded action model of concurrency. It has an elegant semantics, which makes it well suited for formal reasoning. To date, a number of BSV designs have been verified with hand proofs, but little work has been conducted on the application of automated reasoning. We present a prototype shallow embedding of BSV in the PVS theorem prover. Our embedding is compatible with the PVS model checker, which can automatically prove an important class of theorems, and can also be used in conjunction with the powerful proof strategies of PVS to verify a broader class of properties than can be achieved with model checking alone.

  3. A 115 kDa calmodulin-binding protein is located in rat liver endosome fractions.

    PubMed Central

    Enrich, C; Bachs, O; Evans, W H

    1988-01-01

    The distribution of calmodulin-binding polypeptides in various rat liver subcellular fractions was investigated. Plasma-membrane, endosome, Golgi and lysosome fractions were prepared by established procedures. The calmodulin-binding polypeptides present in the subcellular fractions were identified by using an overlay technique after transfer from gels to nitrocellulose sheets. Distinctive populations of calmodulin-binding polypeptides were present in all the fractions examined except lysosomes. A major 115 kDa calmodulin-binding polypeptide of pI 4.3 was located to the endosome subfractions, and it emerges as a candidate endosome-specific protein. Partitioning of endosome fractions between aqueous and Triton X-114 phases indicated that the calmodulin-binding polypeptide was hydrophobic. Major calmodulin-binding polypeptides of 140 and 240 kDa and minor polypeptides of 40-60 kDa were present in plasma membranes. The distribution of calmodulin in the various endosome and plasma-membrane fractions was also analysed, and the results indicated that the amounts were high compared with those in the cytosol. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. PMID:3214436

  4. A 21-35 kDa Mixed Protein Component from Helicobacter pylori Activates Mast Cells Effectively in Chronic Spontaneous Urticaria.

    PubMed

    Tan, Ran-Jing; Sun, He-Qiang; Zhang, Wei; Yuan, Han-Mei; Li, Bin; Yan, Hong-Tao; Lan, Chun-Hui; Yang, Jun; Zhao, Zhuo; Wu, Jin-Jin; Wu, Chao

    2016-12-01

    Helicobacter pylori (H. pylori) seem to involve in the etiology of chronic spontaneous urticaria (CSU). But studies of the pathogenic mechanism are very little. In this study, we detected the serum-specific anti-H. pylori IgG and IgE antibodies in 211 CSU and 137 normal subjects by enzyme-linked immunosorbent assay (ELISA), evaluated the direct activation effects of H. pylori preparations and its protein components on human LAD 2 mast cell line in vitro, and analyzed the specific protein ingredients and functions of the most effective H. pylori mixed protein component using liquid chromatography-mass spectrometry and ELISA assay. In CSU patients, the positive rate of anti-H. pylori IgG positive rate was significantly higher than that in normal controls, and the anti-H. pylori IgE levels had no statistical difference between H. pylori-infected patients with and without CSU. Further studies suggested that H. pylori preparations can directly activate human LAD 2 mast cell line in a dose-dependent manner and its most powerful protein component was a mixture of 21-35 kDa proteins. Moreover, the 21-35 kDa mixed protein component mainly contained 23 kinds of proteins, which can stimulate the release of histamine, TNF-a, IL-3, IFN-γ, and LTB4 by LAD 2 cells in a dose-dependent or time-dependent manner. A 21-35 kDa mixed protein component should be regarded as the most promising pathogenic factor contributing to the CSU associated with H. pylori infection. © 2016 John Wiley & Sons Ltd.

  5. Size-Sorting Combined with Improved Nanocapillary-LC-MS for Identification of Intact Proteins up to 80 kDa

    PubMed Central

    Vellaichamy, Adaikkalam; Tran, John C.; Catherman, Adam D.; Lee, Ji Eun; Kellie, John F.; Sweet, Steve M.M.; Zamdborg, Leonid; Thomas, Paul M.; Ahlf, Dorothy R.; Durbin, Kenneth R.; Valaskovic, Gary A.; Kelleher, Neil L.

    2010-01-01

    Despite the availability of ultra-high resolution mass spectrometers, methods for separation and detection of intact proteins for proteome-scale analyses are still in a developmental phase. Here we report robust protocols for on-line LC-MS to drive high-throughput top-down proteomics in a fashion similar to bottom-up. Comparative work on protein standards showed that a polymeric stationary phase led to superior sensitivity over a silica-based medium in reversed-phase nanocapillary-LC, with detection of proteins >50 kDa routinely accomplished in the linear ion trap of a hybrid Fourier-Transform mass spectrometer. Protein identification was enabled by nozzle-skimmer dissociation (NSD) and detection of fragment ions with <5 ppm mass accuracy for highly-specific database searching using custom software. This overall approach led to identification of proteins up to 80 kDa, with 10-60 proteins identified in single LC-MS runs of samples from yeast and human cell lines pre-fractionated by their molecular weight using a gel-based sieving system. PMID:20073486

  6. Genetic diversity of transmission-blocking vaccine candidate Pvs48/45 in Plasmodium vivax populations in China.

    PubMed

    Feng, Hui; Gupta, Bhavna; Wang, Meilian; Zheng, Wenqi; Zheng, Li; Zhu, Xiaotong; Yang, Yimei; Fang, Qiang; Luo, Enjie; Fan, Qi; Tsuboi, Takafumi; Cao, Yaming; Cui, Liwang

    2015-12-01

    The male gamete fertilization factor P48/45 in malaria parasites is a prime transmission-blocking vaccine (TBV) candidate. Efforts to develop antimalarial vaccines are often thwarted by genetic diversity of the target antigens. Here we evaluated the genetic diversity of Pvs48/45 gene in global Plasmodium vivax populations. We determined 200 Pvs48/45 sequences collected from temperate and subtropical parasite populations in China. Population genetic and evolutionary analyses were performed to determine the levels of genetic diversity, potential signature of selection, and population differentiation. Analysis of the Pvs48/45 sequences from 200 P. vivax parasites collected in a temperate and a tropical region revealed a low level of genetic diversity (π = 0.0012) with 14 single nucleotide polymorphisms, of which 11 were nonsynonymous. Analysis of 344 Pvs48/45 sequences from nine worldwide P. vivax populations detected a total of 38 haplotypes, of which 13 haplotypes were present only once. Multiple tests for selection confirmed a signature of positive selection on Pvs48/45 with selection skewed to the second cysteine domain. Haplotype network analysis and Wright's fixation index showed large geographical differentiation with the presence of continent-or region-specific mutations in this gene. Pvs48/45 displays low levels of genetic diversity with the presence of region-specific mutations. Some of the mutations may be potential epitope targets based on their positions in the predicted structure, highlighting the need for future evaluation of these mutations in designing Pvs48/45-based TBV.

  7. Cloning and characterization of mouse extracellular-signal-regulated protein kinase 3 as a unique gene product of 100 kDa.

    PubMed

    Turgeon, B; Saba-El-Leil, M K; Meloche, S

    2000-02-15

    MAP (mitogen-activated protein) kinases are a family of serine/threonine kinases that have a pivotal role in signal transduction. Here we report the cloning and characterization of a mouse homologue of extracellular-signal-regulated protein kinase (ERK)3. The mouse Erk3 cDNA encodes a predicted protein of 720 residues, which displays 94% identity with human ERK3. Transcription and translation of this cDNA in vitro generates a 100 kDa protein similar to the human gene product ERK3. Immunoblot analysis with an antibody raised against a unique sequence of ERK3 also recognizes a 100 kDa protein in mouse tissues. A single transcript of Erk3 was detected in every adult mouse tissue examined, with the highest expression being found in the brain. Interestingly, expression of Erk3 mRNA is acutely regulated during mouse development, with a peak of expression observed at embryonic day 11. The mouse Erk3 gene was mapped to a single locus on central mouse chromosome 9, adjacent to the dilute mutation locus and in a region syntenic to human chromosome 15q21. Finally, we provide several lines of evidence to support the existence of a unique Erk3 gene product of 100 kDa in mammalian cells.

  8. NASA Requirements for Ground-Based Pressure Vessels and Pressurized Systems (PVS). Revision C

    NASA Technical Reports Server (NTRS)

    Greulich, Owen Rudolf

    2017-01-01

    The purpose of this document is to ensure the structural integrity of PVS through implementation of a minimum set of requirements for ground-based PVS in accordance with this document, NASA Policy Directive (NPD) 8710.5, NASA Safety Policy for Pressure Vessels and Pressurized Systems, NASA Procedural Requirements (NPR) 8715.3, NASA General Safety Program Requirements, applicable Federal Regulations, and national consensus codes and standards (NCS).

  9. Maize 27 kDa gamma-zein is a potential allergen for early weaned pigs.

    PubMed

    Krishnan, Hari B; Kerley, Monty S; Allee, Gary L; Jang, Sungchan; Kim, Won-Seok; Fu, Chunjiang J

    2010-06-23

    Soybean and maize are extensively used in animal feed, primarily in poultry, swine, and cattle diets. Soybean meal can affect pig performance in the first few weeks following weaning and elicit specific antibodies in weaned piglets. Though maize is a major component of pig feed, it is not known if any of the maize proteins can elicit immunological response in young pigs. In this study, we have identified a prominent 27 kDa protein from maize as an immunodominant protein in young pigs. This protein, like some known allergens, exhibited resistance to pepsin digestion in vitro. Several lines of evidence identify the immunodominant 27 kDa protein as a gamma-zein, a maize seed storage protein. First, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of different solubility classes of maize seed proteins revealed the presence of an abundant 27 kDa protein in the prolamin (zein) fraction. Antibodies raised against the purified maize 27 kDa gamma-zein also reacted against the same protein recognized by the young pig serum. Additionally, matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of the peptides generated by trypsin digestion of the immunodominant 27 kDa protein showed significant homology to the maize 27 kDa gamma-zein. Since eliminating the allergenic protein will have a great impact on the nutritive value of the maize meal and expand its use in the livestock industry, it will be highly desirable to develop maize cultivars completely lacking the 27 kDa allergenic protein.

  10. Cooperative Interactions between 480 kDa Ankyrin-G and EB Proteins Assemble the Axon Initial Segment.

    PubMed

    Fréal, Amélie; Fassier, Coralie; Le Bras, Barbara; Bullier, Erika; De Gois, Stéphanie; Hazan, Jamilé; Hoogenraad, Casper C; Couraud, François

    2016-04-20

    The axon initial segment (AIS) is required for generating action potentials and maintaining neuronal polarity. Significant progress has been made in deciphering the basic building blocks composing the AIS, but the underlying mechanisms required for AIS formation remains unclear. The scaffolding protein ankyrin-G is the master-organizer of the AIS. Microtubules and their interactors, particularly end-binding proteins (EBs), have emerged as potential key players in AIS formation. Here, we show that the longest isoform of ankyrin-G (480AnkG) selectively associates with EBs via its specific tail domain and that this interaction is crucial for AIS formation and neuronal polarity in cultured rodent hippocampal neurons. EBs are essential for 480AnkG localization and stabilization at the AIS, whereas 480AnkG is required for the specific accumulation of EBs in the proximal axon. Our findings thus provide a conceptual framework for understanding how the cooperative relationship between 480AnkG and EBs induces the assembly of microtubule-AIS structures in the proximal axon. Neuronal polarity is crucial for the proper function of neurons. The assembly of the axon initial segment (AIS), which is the hallmark of early neuronal polarization, relies on the longest 480 kDa ankyrin-G isoform. The microtubule cytoskeleton and its interacting proteins were suggested to be early key players in the process of AIS formation. In this study, we show that the crosstalk between 480 kDa ankyrin-G and the microtubule plus-end tracking proteins, EBs, at the proximal axon is decisive for AIS assembly and neuronal polarity. Our work thus provides insight into the functional mechanisms used by 480 kDa ankyrin-G to drive the AIS formation and thereby to establish neuronal polarity. Copyright © 2016 the authors 0270-6474/16/364421-13$15.00/0.

  11. Characterization of vitellogenin and its derived yolk proteins in cloudy catshark (Scyliorhinus torazame).

    PubMed

    Yamane, Kodai; Yagai, Tomoki; Nishimiya, Osamu; Sugawara, Rieko; Amano, Haruna; Fujita, Toshiaki; Hiramatsu, Naoshi; Todo, Takashi; Matsubara, Takahiro; Hara, Akihiko

    2013-04-01

    Elasmobranchs (sharks and rays) exhibit unique reproductive characteristics and, in contrast to the situation in teleosts, very little is known about the identity, structure and physical characteristics of their egg yolk proteins. The aims of this study were to (1) detect and purify the vitellogenin (Vtg; egg yolk precursor) and yolk proteins (YPs) of the cloudy catshark (Scyliorhinus torazame), (2) examine the relationships between Vtg and YPs and (3) characterize and classify the deduced primary structure of the Vtg transcript (vtg). The apparent molecular weights of purified Vtg and putative Vtg-related YPs (lipovitellin: Lv, phosvitin: Pv) were determined by gel filtration and were ~560, >669 and ~58 kDa, respectively. Following SDS-PAGE, these purified products (i.e., Vtg, Lv and Pv) appeared as bands of ~210, ~110 and ~22 kDa, respectively. On Western blots, antisera against purified Vtg, Lv and Pv recognized the ~210 kDa Vtg band. Catshark Pv, in contrast to teleost Pvs, had a very low serine content. The catshark Vtg cDNA sequence (vtg) appeared to contain an open-reading frame consisting of domains encoding Lv, Pv and β'-component (β'-c). A phylogenetic analysis, with a consideration of genome duplication events, placed catshark vtg into the 'vtgAB type.' It is concluded that at least a single major type of Vtg protein, which is transcribed and translated from catshark vtgAB gene, is the precursor of three egg yolk proteins (Lv, Pv and β'-c) in catshark.

  12. Garlic virus X 11-kDa protein granules move within the cytoplasm and traffic a host protein normally found in the nucleolus.

    PubMed

    Lu, Yuwen; Yan, Fei; Guo, Wei; Zheng, Hongying; Lin, Lin; Peng, Jiejun; Adams, Michael J; Chen, Jianping

    2011-09-01

    The subcellular localization of the 11-kDa protein (p11) encoded by ORF3 of Garlic virus X (GarVX; genus Allexivirus, family Alphaflexiviridae) was examined by confocal microscopy. Granules with intense fluorescence were visible on the endoplasmic reticulum when p11 fused with green or red fluorescent protein (GFP or RFP) was expressed in epidermal cells of Nicotiana benthamiana. Moreover, the p11-RFP granules moved in the cytoplasm, along the cell periphery and through the cell membranes to adjacent cells. A 17-kDa protein (p17) of garlic interacting with p11 was identified by yeast two-hybridization and bimolecular fluorescence complementation assay. When p17 fused to GFP was expressed in epidermal cells of N. benthamiana, it localized to the nucleolus. However, in the presence of GarVX p11, the distribution of p17 changed to that of p11, but did not appear to affect the pattern of movement of p11. MOLECULAR PLANT PATHOLOGY © 2011 BSPP AND BLACKWELL PUBLISHING LTD. NO CLAIM TO ORIGINAL US GOVERNMENT WORKS.

  13. pvsR: An Open Source Interface to Big Data on the American Political Sphere

    PubMed Central

    2015-01-01

    Digital data from the political sphere is abundant, omnipresent, and more and more directly accessible through the Internet. Project Vote Smart (PVS) is a prominent example of this big public data and covers various aspects of U.S. politics in astonishing detail. Despite the vast potential of PVS’ data for political science, economics, and sociology, it is hardly used in empirical research. The systematic compilation of semi-structured data can be complicated and time consuming as the data format is not designed for conventional scientific research. This paper presents a new tool that makes the data easily accessible to a broad scientific community. We provide the software called pvsR as an add-on to the R programming environment for statistical computing. This open source interface (OSI) serves as a direct link between a statistical analysis and the large PVS database. The free and open code is expected to substantially reduce the cost of research with PVS’ new big public data in a vast variety of possible applications. We discuss its advantages vis-à-vis traditional methods of data generation as well as already existing interfaces. The validity of the library is documented based on an illustration involving female representation in local politics. In addition, pvsR facilitates the replication of research with PVS data at low costs, including the pre-processing of data. Similar OSIs are recommended for other big public databases. PMID:26132154

  14. The 30 kDa protein co-purified with chick liver glutathione S-transferases is a carbonyl reductase.

    PubMed

    Tsai, S P; Wang, L Y; Yeh, H I; Tam, M F

    1996-02-08

    An unidentified 30 kDa protein was co-purified with chick liver glutathione S-transferases from S-hexylglutathione affinity column. The protein was isolated to apparent homogeneity with chromatofocusing. The molecular mass of the protein was determined to be 30 277 +/- 3 dalton by mass spectrometry. The protein was digested with Achromobacter proteinase I. Amino-acid sequence analyses of the resulting peptides show a high degree of identity with those of human carbonyl reductase. The protein is active with menadione as substrate. Thus, it is identified as chick liver carbonyl reductase.

  15. Biofortification of soybean meal: immunological properties of the 27 kDa γ-zein.

    PubMed

    Krishnan, Hari B; Jang, Sungchan; Kim, Won-Seok; Kerley, Monty S; Oliver, Melvin J; Trick, Harold N

    2011-02-23

    Legumes, including soybeans ( Glycine max ), are deficient in sulfur-containing amino acids, which are required for the optimal growth of monogastric animals. This deficiency can be overcome by expressing heterologous proteins rich in sulfur-containing amino acids in soybean seeds. A maize 27 kDa γ-zein, a cysteine-rich protein, has been successfully expressed in several crops including soybean, barley, and alfalfa with the intent to biofortify these crops for animal feed. Previous work has shown that the maize 27 kDa zein can withstand digestion by pepsin and elicit an immunogenic response in young pigs. By use of sera from patients who tested positive by ImmunoCAP assay for elevated IgE to maize proteins, specific IgE binding to the 27 kDa γ-zein is demonstrated. Bioinformatic analysis using the full-length and 80 amino acid sliding window FASTA searches identified significant sequence homology of the 27 kDa γ-zein with several known allergens. Immunoblot analysis using human serum that cross-reacts with maize seed proteins also revealed specific IgE-binding to the 27 kDa γ-zein in soybean seed protein extracts containing the 27 kDa zein. This study demonstrates for the first time the allergenicity potential of the 27 kDa γ-zein and the potential that this protein has to limit livestock performance when used in soybeans that serve as a biofortified feed supplement.

  16. Solid-state NMR spectroscopy of 18.5 kDa myelin basic protein reconstituted with lipid vesicles: spectroscopic characterisation and spectral assignments of solvent-exposed protein fragments.

    PubMed

    Zhong, Ligang; Bamm, Vladimir V; Ahmed, Mumdooh A M; Harauz, George; Ladizhansky, Vladimir

    2007-12-01

    Myelin basic protein (MBP, 18.5 kDa isoform) is a peripheral membrane protein that is essential for maintaining the structural integrity of the multilamellar myelin sheath of the central nervous system. Reconstitution of the most abundant 18.5 kDa MBP isoform with lipid vesicles yields an aggregated assembly mimicking the protein's natural environment, but which is not amenable to standard solution NMR spectroscopy. On the other hand, the mobility of MBP in such a system is variable, depends on the local strength of the protein-lipid interaction, and in general is of such a time scale that the dipolar interactions are averaged out. Here, we used a combination of solution and solid-state NMR (ssNMR) approaches: J-coupling-driven polarization transfers were combined with magic angle spinning and high-power decoupling to yield high-resolution spectra of the mobile fragments of 18.5 kDa murine MBP in membrane-associated form. To partially circumvent the problem of short transverse relaxation, we implemented three-dimensional constant-time correlation experiments (NCOCX, NCACX, CONCACX, and CAN(CO)CX) that were able to provide interresidue and intraresidue backbone correlations. These experiments resulted in partial spectral assignments for mobile fragments of the protein. Additional nuclear Overhauser effect spectroscopy (NOESY)-based experiments revealed that the mobile fragments were exposed to solvent and were likely located outside the lipid bilayer, or in its hydrophilic portion. Chemical shift index analysis showed that the fragments were largely disordered under these conditions. These combined approaches are applicable to ssNMR investigations of other peripheral membrane proteins reconstituted with lipids.

  17. Accumulation of 52 kDa glycine rich protein in auxin-deprived strawberry fruits and its role in fruit growth. [Fragaria ananassa

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reddy, A.S.N.; Poovaiah, B.W.

    1987-04-01

    Growth of strawberry (Fragaria ananassa Duch) receptacles can be stopped at any stage by deachening the fruits and can be resumed by exogenous application of auxin. In their earlier studies they demonstrated auxin regulated polypeptide changes at different stages of strawberry fruit development. Removal of achenes from fruits to deprive auxin resulted in the accumulation of 52 KDa polypeptide. This polypeptide is associated with cell wall and its concentration is increased in a time-dependent manner in auxin deprived receptacles. Incorporation studies with (/sup 35/S) methionine showed the promotion of labelling of 52 kDa polypeptide in the auxin-deprived receptacles within 12more » h after removal of the achenes. Amino acid analysis revealed that the 52 KDa polypeptide is rich in glycine. Their studies, with normal and mutant strawberry receptacles, indicate that the synthesis and accumulation of this glycine rich protein correlates with cessation of receptacle growth. These results suggest a role for the glycine rich protein in growth.« less

  18. Characterization of the Lymantria dispar nucleopolyhedrovirus 25K FP gene

    Treesearch

    David S. Bischoff; James M. Slavicek

    1996-01-01

    The Lymantria dispar nucleopolyhedrovirus (LdMNPV) gene encoding the 25K FP protein has been cloned and sequenced. The 25KFP gene codes for a 217 amino acid protein with a predicted molecular mass of 24870 Da. Expression of the 25K FP protein in a rabbit reticulocyte system generated a 27 kDa protein, in close agreement with the...

  19. Modeling and Docking Studies on Novel Mutants (K71L and T204V) of the ATPase Domain of Human Heat Shock 70 kDa Protein 1

    PubMed Central

    Elengoe, Asita; Naser, Mohammed Abu; Hamdan, Salehhuddin

    2014-01-01

    The purpose of exploring protein interactions between human adenovirus and heat shock protein 70 is to exploit a potentially synergistic interaction to enhance anti-tumoral efficacy and decrease toxicity in cancer treatment. However, the protein interaction of Hsp70 with E1A32 kDa of human adenovirus serotype 5 remains to be elucidated. In this study, two residues of ATPase domain of human heat shock 70 kDa protein 1 (PDB: 1 HJO) were mutated. 3D mutant models (K71L and T204V) using PyMol software were then constructed. The structures were evaluated by PROCHECK, ProQ, ERRAT, Verify 3D and ProSA modules. All evidence suggests that all protein models are acceptable and of good quality. The E1A32 kDa motif was retrieved from UniProt (P03255), as well as subjected to docking interaction with NBD, K71L and T204V, using the Autodock 4.2 program. The best lowest binding energy value of −9.09 kcal/mol was selected for novel T204V. Moreover, the protein-ligand complex structures were validated by RMSD, RMSF, hydrogen bonds and salt bridge analysis. This revealed that the T204V-E1A32 kDa motif complex was the most stable among all three complex structures. This study provides information about the interaction between Hsp70 and the E1A32 kDa motif, which emphasizes future perspectives to design rational drugs and vaccines in cancer therapy. PMID:24758925

  20. Structural and functional studies of a 50 kDa antigenic protein from Salmonella enterica serovar Typhi.

    PubMed

    Choong, Yee Siew; Lim, Theam Soon; Chew, Ai Lan; Aziah, Ismail; Ismail, Asma

    2011-04-01

    The high typhoid incidence rate in developing and under-developed countries emphasizes the need for a rapid, affordable and accessible diagnostic test for effective therapy and disease management. TYPHIDOT®, a rapid dot enzyme immunoassay test for typhoid, was developed from the discovery of a ∼50 kDa protein specific for Salmonella enterica serovar Typhi. However, the structure of this antigen remains unknown till today. Studies on the structure of this antigen are important to elucidate its function, which will in turn increase the efficiency of the development and improvement of the typhoid detection test. This paper described the predictive structure and function of the antigenically specific protein. The homology modeling approach was employed to construct the three-dimensional structure of the antigen. The built structure possesses the features of TolC-like outer membrane protein. Molecular docking simulation was also performed to further probe the functionality of the antigen. Docking results showed that hexamminecobalt, Co(NH(3))(6)(3+), as an inhibitor of TolC protein, formed favorable hydrogen bonds with D368 and D371 of the antigen. The single point (D368A, D371A) and double point (D368A and D371A) mutations of the antigen showed a decrease (single point mutation) and loss (double point mutations) of binding affinity towards hexamminecobalt. The architecture features of the built model and the docking simulation reinforced and supported that this antigen is indeed the variant of outer membrane protein, TolC. As channel proteins are important for the virulence and survival of bacteria, therefore this ∼50 kDa channel protein is a good specific target for typhoid detection test. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Influence of 120 kDa Pyruvate:Ferredoxin Oxidoreductase on Pathogenicity of Trichomonas vaginalis.

    PubMed

    Song, Hyun-Ouk

    2016-02-01

    Trichomonas vaginalis is a flagellate protozoan parasite and commonly infected the lower genital tract in women and men. Iron is a known nutrient for growth of various pathogens, and also reported to be involved in establishment of trichomoniasis. However, the exact mechanism was not clarified. In this study, the author investigated whether the 120 kDa protein of T. vaginalis may be involved in pathogenicity of trichomonads. Antibodies against 120 kDa protein of T. vaginalis, which was identified as pyruvate:ferredoxin oxidoreductase (PFOR) by peptide analysis of MALDI-TOF-MS, were prepared in rabbits. Pretreatment of T. vaginalis with anti-120 kDa Ab decreased the proliferation and adherence to vaginal epithelial cells (MS74) of T. vaginalis. Subcutaneous tissue abscess in anti-120 kDa Ab-treated T. vaginalis-injected mice was smaller in size than that of untreated T. vaginalis-infected mice. Collectively, the 120 kDa protein expressed by iron may be involved in proliferation, adhesion to host cells, and abscess formation, thereby may influence on the pathogenicity of T. vaginalis.

  2. Jojoba seed meal proteins associated with proteolytic and protease inhibitory activities.

    PubMed

    Shrestha, Madan K; Peri, Irena; Smirnoff, Patricia; Birk, Yehudith; Golan-Goldhirsh, Avi

    2002-09-25

    The jojoba, Simmondsia chinensis, is a characteristic desert plant native to the Sonoran desert. The jojoba meal after oil extraction is rich in protein. The major jojoba proteins were albumins (79%) and globulins (21%), which have similar amino acid compositions and also showed a labile thrombin-inhibitory activity. SDS-PAGE showed two major proteins at 50 kDa and 25 kDa both in the albumins and in the globulins. The 25 kDa protein has trypsin- and chymotrypsin-inhibitory activities. In vitro digestibility of the globulins and albumins resembled that of casein and soybean protein concentrates and was increased after heat treatment. The increased digestibility achieved by boiling may be attributed to inactivation of the protease inhibitors and denaturation of proteins.

  3. Frequency Control Using On line Learning Method for Island Smart Grid with EVs and PVs

    DTIC Science & Technology

    2014-07-06

    deviation from PVs are modeled as the power disturbance for the system . A. Case 1: active power disturbance without EVs constraints In this case, there are...IEEE Transactions on, vol. 3, no. 1, pp. 565–577, 2012. [7] M. Datta and T. Senjyu, “Fuzzy control of distributed pv inverters /energy storage systems ...this linearity assumption. In island smart grid with photovoltaics ( PVs ) and EVs, system state parameters and operating conditions are changing

  4. Cholera toxin-induced ADP-ribosylation of a 46 kDa protein is decreased in brains of ethanol-fed mice

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nhamburo, P.T.; Hoffman, P.L.; Tabakoff, B.

    1988-01-01

    The acute in vitro effects of ethanol on cerebral cortical adenylate cyclase activity and beta-adrenergic receptor characteristics suggested a site of action of ethanol at Gs, the stimulatory guanine nucleotide binding protein. After chronic ethanol ingestion, the beta-adrenergic receptor appeared to be uncoupled (i.e., the form of the receptor with high affinity for agonist was undetectable), and stimulation of adenylate cyclase activity by isoproterenol or guanine nucleotides was reduced, suggesting an alteration in the properties of Gs. To further characterize this change, cholera and pertussis toxin-mediated /sup 32/P-ADP-ribosylation of mouse cortical membranes was assessed in mice that had chronically ingestedmore » ethanol in a liquid diet. /sup 32/P-labeled proteins were separated by SDS-PAGE and quantitated by autoradiography. There was a selective 30-50% decrease in cholera toxin-induced labeling of 46 kDa protein band in membranes of ethanol-fed mice, with no apparent change in pertussis toxin-induced labeling. The 46 kDa protein has a molecular weight similar to that of the alpha subunit of Gs, suggesting a reduced amount of this protein or a change in its characteristics as a substrate for cholera toxin-induced ADP-ribosylation in cortical membranes of ethanol-fed mice.« less

  5. Coq Tacticals and PVS Strategies: A Small Step Semantics

    NASA Technical Reports Server (NTRS)

    Kirchner, Florent

    2003-01-01

    The need for a small step semantics and more generally for a thorough documentation and understanding of Coq's tacticals and PVS's strategies arise with their growing use and the progressive uncovering of their subtleties. The purpose of the following study is to provide a simple and clear formal framework to describe their detailed semantics, and highlight their differences and similarities.

  6. Possible role of the 38 kDa protein, lacking in the gastrula-arrested Xenopus mutant, in gastrulation.

    PubMed

    Tanaka, Tetsuya S; Ikenishi, Kohji

    2002-02-01

    An acidic, 38 kDa protein that is present in Xenopus wild-type embryos has been previously shown to be lacking in gastrula-arrested mutant embryos. To gain understanding of the role of this protein, its spatio-temporal distribution and involvement in gastrulation was investigated using the monoclonal antibody (9D10) against it. The protein was prominent in the cortical cytoplasm of cells facing the outside in the animal hemisphere of embryos until the gastrula stage, and in ciliated epithelial cells of embryos at stages later than the late neurula. When the 9D10 antibody was injected into fertilized wild-type eggs, they cleaved normally, but most of them had arrested development, always at the early stage of gastrulation, as in the mutant embryos. In contrast, the majority of the control antibody-injected eggs gastrulated normally and developed further. Cytoskeletal F-actin, which was mainly observed in the area beneath the plasma membrane facing the outside of the epithelial layer of not only the dorsal involuting marginal zone but also the dorsal, vegetal cell mass of the control antibody-injected embryos at the early gastrula stage, was scarcely recognized in the corresponding area of the 9D10 antibody-injected embryos. It is likely that the paucity of the F-actin caused by the 9D10 antibody inhibition of the 38 kDa protein might lead to a failure of cell movement in gastrulation, resulting in developmental arrest.

  7. Correlation between phosphorylation level of a hippocampal 86kDa protein and extinction of a behaviour in a model of Wernicke-Korsakoff syndrome.

    PubMed

    Pires, Rita G W; Pereira, Sílvia R C; Carvalho, Fabiana M; Oliveira-Silva, Ieda F; Ferraz, Vany P; Ribeiro, Angela M

    2007-06-04

    The effects of chronic ethanol and thiamine deficiency, alone or associated, on hippocampal protein phosphorylation profiles ranging in molecular weight from 30 to 250kDa molecular weight, in stimulated (high K(+) concentration) and unstimulated (basal) conditions were investigated. These treatments significantly changed the phosphorylation level of an 86kDa phosphoprotein. Thiamine deficiency, but not chronic ethanol, induced a decrease in a behavioural extinction index, which is significantly correlated to the phosphorylation level of the p86 protein. These data add to and extend previous findings by our laboratory implicating the involvement of hippocampal neurotransmission components in extinction of a behaviour which involves learning of environmental spatial cues.

  8. Recombinant expression, isolation, and proteolysis of extracellular matrix-secreted phosphoprotein-24 kDa.

    PubMed

    Murray, Elsa J Brochmann; Murray, Samuel S; Simon, Robert; Behnam, Keyvan

    2007-01-01

    Secreted phosphoprotein-24 kDa (spp24) is an extracellular matrix protein first cloned from bone. Bovine spp24 is transcribed as a 203 amino acid residue protein that undergoes cleavage of a secretory peptide to form the mature protein (spp24, residues 24 to 203). While not osteogenic itself, spp24 is degraded to a pro-osteogenic protein, spp18.5, in bone. Both spp18.5 and spp24 contain a cyclic TRH1 (TGF-beta receptor II homology-1) domain similar to that found in the receptor itself and in fetuin. A synthetic peptide corresponding to the TRH1 domain of spp18.5 and spp24 specifically binds BMP-2 and enhances the rate and magnitude of BMP-2-induced ectopic bone formation in vivo. The parental protein, spp24, exhibits a high affinity for bone and mineral complexes, but its abundance there is low, suggesting that it is rapidly degraded. The availability of recombinant spp24 and its degradation products would facilitate the elucidation of their structure:function relationships. We describe here the expression of His(6)-tagged bovine spp24 (residues 24 to 203) in E. coli, its purification by high-resolution IMAC (immobilized metal affinity chromatography), and the characterization of the full-length recombinant 21.5 kDa protein and its two major 16 kDa and 14.5 kDa degradation products (spp24, residues 24 to 157, and spp24, residues 24 to 143) by mass spectroscopy. The recombinant spp24 protein was resistant to proteolysis by MC3T3-E1 osteoblastic cell extracts in the absence of calcium; however, in the presence of 4 mM Ca, it can undergo essentially complete proteolysis to small peptides, bypassing the 16 kDa and 14.5 kDa intermediates. This confirms the proteolytic susceptibility of spp24. It also suggests that the levels of spp24 in bone may be regulated, in part, by calcium-dependent proteolysis mediated by osteoblastic cells.

  9. Molecular cloning and developmental expression of the catalytic and 65-kDa regulatory subunits of protein phosphatase 2A in Drosophila.

    PubMed Central

    Mayer-Jaekel, R E; Baumgartner, S; Bilbe, G; Ohkura, H; Glover, D M; Hemmings, B A

    1992-01-01

    cDNA clones encoding the catalytic subunit and the 65-kDa regulatory subunit of protein phosphatase 2A (PR65) from Drosophila melanogaster have been isolated by homology screening with the corresponding human cDNAs. The Drosophila clones were used to analyze the spatial and temporal expression of the transcripts encoding these two proteins. The Drosophila PR65 cDNA clones contained an open reading frame of 1773 nucleotides encoding a protein of 65.5 kDa. The predicted amino acid sequence showed 75 and 71% identity to the human PR65 alpha and beta isoforms, respectively. As previously reported for the mammalian PR65 isoforms, Drosophila PR65 is composed of 15 imperfect repeating units of approximately 39 amino acids. The residues contributing to this repeat structure show also the highest sequence conservation between species, indicating a functional importance for these repeats. The gene encoding Drosophila PR65 was located at 29B1,2 on the second chromosome. A major transcript of 2.8 kilobase (kb) encoding the PR65 subunit and two transcripts of 1.6 and 2.5 kb encoding the catalytic subunit could be detected throughout Drosophila development. All of these mRNAs were most abundant during early embryogenesis and were expressed at lower levels in larvae and adult flies. In situ hybridization of different developmental stages showed a colocalization of the PR65 and catalytic subunit transcripts. The mRNA expression is high in the nurse cells and oocytes, consistent with a high equally distributed expression in early embryos. In later embryonal development, the expression remains high in the nervous system and the gonads but the overall transcript levels decrease. In third instar larvae, high levels of mRNA could be observed in brain, imaginal discs, and in salivary glands. These results indicate that protein phosphatase 2A transcript levels change during development in a tissue and in a time-specific manner. Images PMID:1320961

  10. Cloning, expression and activation of a truncated 92-kDa gelatinase minienzyme.

    PubMed

    Kröger, M; Tschesche, H

    1997-09-01

    The matrix metalloproteinases (MMPs) are a family of highly homologous zinc-endopeptidases that degrade extracellular matrix components. Human 92-kDa gelatinase (MMP-9) represents one of the MMPs that cleaves native collagen type IV. As a basis for structural investigations, the short form (catalytic domain, amino acid residues 113-450) of the 92-kDa gelatinase cDNA was cloned and expressed in E. coli as a minienzyme. By combination of reverse transcription (RT) and polymerase chain reaction (PCR), the truncated 92-kDa gelatinase-cDNA was amplified from the corresponding mRNA derived from ovarian carcinoma cells. The cDNA fragment obtained was cloned in E. coli and sequenced. With the exception of one nucleotide inversion at position 745 (gt-->tg) the cDNA sequence was identical to the nucleotide sequence of the 92-kDa gelatinase as has been previously reported. The protein was expressed in E. coli using the vector pET-12b. The recombinant protein was stored in inclusion bodies and extracted as a 38 kDa species from the inclusion bodies by solubilization in 8 M urea. The product was purified by affinity chromatography and gel filtration. Amino-terminal sequence analysis confirmed the identity with the catalytic domain of 92-kDa gelatinase. The recombinant protein was refolded in the presence of Ca2+ and Zn2+ and yielded an active minienzyme with gelatinolytic activity. It degrades the native substrate collagen type IV and the synthetic substrate Mca-Pro-Leu-Gly-Leu-Dpa-Ala-Arg-NH2 x AcOH like the full-length 92-kDa gelatinase. The catalytic activity could be inhibited by the specific MMP inhibitors TIMP-1 and TIMP-2.

  11. Alga-Produced Cholera Toxin-Pfs25 Fusion Proteins as Oral Vaccines

    PubMed Central

    Gregory, James A.; Topol, Aaron B.; Doerner, David Z.

    2013-01-01

    Infectious diseases disproportionately affect indigent regions and are the greatest cause of childhood mortality in developing countries. Practical, low-cost vaccines for use in these countries are paramount to reducing disease burdens and concomitant poverty. Algae are a promising low-cost system for producing vaccines that can be orally delivered, thereby avoiding expensive purification and injectable delivery. We engineered the chloroplast of the eukaryotic alga Chlamydomonas reinhardtii to produce a chimeric protein consisting of the 25-kDa Plasmodium falciparum surface protein (Pfs25) fused to the β subunit of the cholera toxin (CtxB) to investigate an alga-based whole-cell oral vaccine. Pfs25 is a promising malaria transmission-blocking vaccine candidate that has been difficult to produce in traditional recombinant systems due to its structurally complex tandem repeats of epidermal growth factor-like domains. The noncatalytic CtxB domain of the cholera holotoxin assembles into a pentameric structure and acts as a mucosal adjuvant by binding GM1 ganglioside receptors on gut epithelial cells. We demonstrate that CtxB-Pfs25 accumulates as a soluble, properly folded and functional protein within algal chloroplasts, and it is stable in freeze-dried alga cells at ambient temperatures. In mice, oral vaccination using freeze-dried algae that produce CtxB-Pfs25 elicited CtxB-specific serum IgG antibodies and both CtxB- and Pfs25-specific secretory IgA antibodies. These data suggest that algae are a promising system for production and oral delivery of vaccine antigens, but as an orally delivered adjuvant, CtxB is best suited for eliciting secretory IgA antibodies for vaccine antigens against pathogens that invade mucosal surfaces using this strategy. PMID:23603678

  12. Modified properties of a glycated and cross-linked soy protein isolate by transglutaminase and an oligochitosan of 5 kDa.

    PubMed

    Fu, Miao; Zhao, Xin-Huai

    2017-01-01

    Soy protein is an important protein ingredient for the food industry; however, its properties can be improved by enzymatic and chemical modifications. This study applied a new enzymatic glycation and cross-linking to modify soy protein isolate (SPI), using an oligochitosan of 5 kDa and transglutaminase. Properties of the obtained glycated and cross-linked SPI (GC-SPI) were unknown and thus assessed. GC-SPI contained glucosamine of 13.6 g kg -1 protein, but less reactable &bond;NH 2 than SPI (0.42 vs. 0.50 mol kg -1 protein). Infrared spectra and circular dichroism results showed that GC-SPI other than SPI and cross-linked SPI had more &bond;OH in molecules, and was more disordered in secondary structure. In comparison with SPI, GC-SPI showed enhanced water-binding capacity, could form aggregates with enlarged hydrodynamic radius (180.2 vs. 82.9 nm) and negative zeta-potential (-31.2 vs. -27.7 mV) in dispersion, but exhibited lower thermal stability (e.g. greater mass loss) upon heating at a temperature above 288 °C. GC-SPI also had lower in vitro proteolytic digestibility than SPI due to the protein cross-linking. Oligochitosan of 5 kDa and transglutaminase can be used to glycate and cross-link SPI. This approach is applicable to generate potential protein ingredient with good hydration and dispersive stabilisation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  13. Yrb4p, a yeast ran-GTP-binding protein involved in import of ribosomal protein L25 into the nucleus.

    PubMed Central

    Schlenstedt, G; Smirnova, E; Deane, R; Solsbacher, J; Kutay, U; Görlich, D; Ponstingl, H; Bischoff, F R

    1997-01-01

    Gsp1p, the essential yeast Ran homologue, is a key regulator of transport across the nuclear pore complex (NPC). We report the identification of Yrb4p, a novel Gsp1p binding protein. The 123 kDa protein was isolated from Saccharomyces cerevisiae cells and found to be related to importin-beta, the mediator of nuclear localization signal (NLS)-dependent import into the nucleus, and to Pse1p. Like importin-beta, Yrb4p and Pse1p specifically bind to Gsp1p-GTP, protecting it from GTP hydrolysis and nucleotide exchange. The GTPase block of Gsp1p complexed to Yrb4p or Pse1p is released by Yrb1p, which contains a Gsp1p binding domain distinct from that of Yrb4p. This might reflect an in vivo function for Yrb1p. Cells disrupted for YRB4 are defective in nuclear import of ribosomal protein L25, but show no defect in the import of proteins containing classical NLSs. Expression of a Yrb4p mutant deficient in Gsp1p-binding is dominant-lethal and blocks bidirectional traffic across the NPC in wild-type cells. L25 binds to Yrb4p and Pse1p and is released by Gsp1p-GTP. Consistent with its putative role as an import receptor for L25-like proteins, Yrb4p localizes to the cytoplasm, the nucleoplasm and the NPC. PMID:9321403

  14. Sequential recognition of the pre-mRNA branch point by U2AF65 and a novel spliceosome-associated 28-kDa protein.

    PubMed Central

    Gaur, R K; Valcárcel, J; Green, M R

    1995-01-01

    Splicing of pre-mRNAs occurs via a lariat intermediate in which an intronic adenosine, embedded within a branch point sequence, forms a 2',5'-phosphodiester bond (RNA branch) with the 5' end of the intron. How the branch point is recognized and activated remains largely unknown. Using site-specific photochemical cross-linking, we have identified two proteins that specifically interact with the branch point during the splicing reaction. U2AF65, an essential splicing factor that binds to the adjacent polypyrimidine tract, crosslinks to the branch point at the earliest stage of spliceosome formation in an ATP-independent manner. A novel 28-kDa protein, which is a constituent of the mature spliceosome, contacts the branch point after the first catalytic step. Our results indicate that the branch point is sequentially recognized by distinct splicing factors in the course of the splicing reaction. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 FIGURE 8 FIGURE 9 PMID:7493318

  15. Nucleopolyhedroviruses (NPV) induce the expression of small heat shock protein 25.4 in Antheraea pernyi.

    PubMed

    Zhang, Congfen; Zhu, Baojian; Dai, Li Shang; Liu, Chaoliang; Luo, Xuegang

    2016-10-15

    Nucleopolyhedroviruses (NPVs) is one group of Baculoviruses. The infection of NPV in silkworm is often lethal. To investigate the effective measures to stop the infection of NPV, we cloned cDNA encoding small heat shock protein 25.4 in Antheraea pernyi (Ap-HSP25.4). The translated amino acid sequence consisted of 223 residues with a calculated molecular mass of 25.4kDa and an isoelectronic point (pI) of 4.93. Quantitative real-time PCR was used to investigate the expression patterns and distribution profiles of Ap-sHSP25.4 before and after challenged with NPV. We found that the inhibitors of eicosanoid synthesis could suppress the transcription of Ap-sHSP25.4 in the fat body in a dose dependent manner. And arachidonic acid induced the expression of Ap-sHSP25.4. Thus, we concluded that sHSPs may be promising candidates to boost insect immunity in practice. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Precursor binding to an 880-kDa Toc complex as an early step during active import of protein into chloroplasts.

    PubMed

    Chen, Kuan-Yu; Li, Hsou-min

    2007-01-01

    The import of protein into chloroplasts is mediated by translocon components located in the chloroplast outer (the Toc proteins) and inner (the Tic proteins) envelope membranes. To identify intermediate steps during active import, we used sucrose density gradient centrifugation and blue-native polyacrylamide gel electrophoresis (BN-PAGE) to identify complexes of translocon components associated with precursor proteins under active import conditions instead of arrested binding conditions. Importing precursor proteins in solubilized chloroplast membranes formed a two-peak distribution in the sucrose density gradient. The heavier peak was in a similar position as the previously reported Tic/Toc supercomplex and was too large to be analyzed by BN-PAGE. The BN-PAGE analyses of the lighter peak revealed that precursors accumulated in at least two complexes. The first complex migrated at a position close to the ferritin dimer (approximately 880 kDa) and contained only the Toc components. Kinetic analyses suggested that this Toc complex represented an earlier step in the import process than the Tic/Toc supercomplex. The second complex in the lighter peak migrated at the position of the ferritin trimer (approximately 1320 kDa). It contained, in addition to the Toc components, Tic110, Hsp93, and an hsp70 homolog, but not Tic40. Two different precursor proteins were shown to associate with the same complexes. Processed mature proteins first appeared in the membranes at the same fractions as the Tic/Toc supercomplex, suggesting that processing of transit peptides occurs while precursors are still associated with the supercomplex.

  17. Precursor binding to an 880-kDa Toc complex as an early step during active import of protein into chloroplasts

    PubMed Central

    Chen, Kuan-Yu; Li, Hsou-min

    2007-01-01

    The import of protein into chloroplasts is mediated by translocon components located in the chloroplast outer (the Toc proteins) and inner (the Tic proteins) envelope membranes. To identify intermediate steps during active import, we used sucrose density gradient centrifugation and blue-native polyacrylamide gel electrophoresis (BN-PAGE) to identify complexes of translocon components associated with precursor proteins under active import conditions instead of arrested binding conditions. Importing precursor proteins in solubilized chloroplast membranes formed a two-peak distribution in the sucrose density gradient. The heavier peak was in a similar position as the previously reported Tic/Toc supercomplex and was too large to be analyzed by BN-PAGE. The BN-PAGE analyses of the lighter peak revealed that precursors accumulated in at least two complexes. The first complex migrated at a position close to the ferritin dimer (approximately 880 kDa) and contained only the Toc components. Kinetic analyses suggested that this Toc complex represented an earlier step in the import process than the Tic/Toc supercomplex. The second complex in the lighter peak migrated at the position of the ferritin trimer (approximately 1320 kDa). It contained, in addition to the Toc components, Tic110, Hsp93, and an hsp70 homolog, but not Tic40. Two different precursor proteins were shown to associate with the same complexes. Processed mature proteins first appeared in the membranes at the same fractions as the Tic/Toc supercomplex, suggesting that processing of transit peptides occurs while precursors are still associated with the supercomplex. PMID:17144891

  18. Saccharomyces cerevisiae-Secreted Fusion Proteins Pfs25 and Pfs28 Elicit Potent Plasmodium falciparum Transmission-Blocking Antibodies in Mice

    PubMed Central

    Gozar, Mary Margaret G.; Price, Virginia L.; Kaslow, David C.

    1998-01-01

    Transmission-blocking vaccines based on sexual-stage surface antigens of Plasmodium falciparum may assist in the control of this lethal form of human malaria. Two vaccine candidates, Pfs25 and Pfs28, were produced as single recombinant fusion proteins. The 39-kDa chimeric proteins, having a C-terminal His6 tag, were secreted by Saccharomyces cerevisiae, using the prepro-α-factor leader sequence. Pfs25-28 fusion proteins were significantly more potent than either Pfs25 or Pfs28 alone in eliciting antibodies in mice that blocked oocyst development in Anopheles freeborni mosquitoes: complete inhibition of oocyst development in the mosquito midgut was achieved with fewer vaccinations, at a lower dose, and for a longer duration than with either Pfs25 or Pfs28 alone. Increased antigen-specific immunoglobulin G titers and highly significant lymphoproliferative stimulation by Pfs28-containing antigens suggest the presence of an immunodominant helper T-cell epitope in the Pfs28 portion of the fusion proteins. This epitope may be responsible for the enhanced humoral response to both Pfs25 and Pfs28 antigens. Protein production of the fusion protein was improved 12-fold by converting Pfs28 codons to yeast-preferred codons (TBV28), using a modified ADH2 promoter and incorporating a (Glu-Ala)2 repeat after the Kex2 cleavage site. PMID:9423839

  19. Regulation of post-translational protein arginine methylation during HeLa cell cycle.

    PubMed

    Kim, Chongtae; Lim, Yongchul; Yoo, Byong Chul; Won, Nam Hee; Kim, Sangduk; Kim, Gieun

    2010-09-01

    Post-translational arginine methylation which modifies protein-arginyl residues by protein arginine methyltransferase (PRMT) was investigated during synchronized HeLa cell cycle. The lysates of cells synchronized at each stage were subjected to one and/or two dimensional electrophoresis followed by Western immunoblot using against anti-asymmetric-dimethyl-arginine (ASYM24), anti-symmetric-dimethyl-arginine (SYM10), and subclasses of PRMTs, including PRMT1, PRMT3, PRMT4 (CARM1), PRMT5, PRMT6, and PRMT7 antibodies. Proteins with approximate molecular masses of 80 kDa, 68 kDa, and 64 kDa, containing asymmetric-dimethyl-arginine (aDMA) were increased at G0/G1 to G1, which lasted until S phase. In addition, 25 kDa protein of symmetric-dimethyl-arginine (sDMA) was also markedly up-regulated from G0/G1 to G1. The levels of PRMT3, PRMT6 and PRMT7 were concurrently increased during the cell cycle. Two-dimensional gel electrophoresis followed by MALDI-TOF-MS was identified as aDMA-80 kDa and aDMA-68 kDa proteins as heterogeneous nuclear ribonucleoprotein R (hnRNPR), aDMA-64 kDa proteins as cleavage stimulation factor 64 kDa subunit (CstF-64), and sDMA-25 kDa protein as triosephosphate isomerase (TPI). The levels of increased aDMA of hnRNPR were reduced, when HeLa cells were transfected with siRNA for PRMT1, and the aDMA of CstF-64 with siRNA for PRMT3, while depletion of PRMT5 down-regulated sDMA of TPI. Protein arginine dimethylations of hnRNPR, CstF-64, and TPI were regulated during HeLa cell cycle by respective PRMTs. These results suggest that regulation of arginine dimethylation of hnRNPR, CstF-64, and TPI at G0/G1 to G1 are most likely to modulate the cellular growth and proliferation in HeLa cell cycle. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. Formation of the 67-kDa laminin receptor by acylation of the precursor.

    PubMed

    Butò, S; Tagliabue, E; Ardini, E; Magnifico, A; Ghirelli, C; van den Brûle, F; Castronovo, V; Colnaghi, M I; Sobel, M E; Ménard, S

    1998-06-01

    Even though the involvement of the 67-kDa laminin receptor (67LR) in tumor invasiveness has been clearly demonstrated, its molecular structure remains an open problem, since only a full-length gene encoding a 37-kDa precursor protein (37LRP) has been isolated so far. A pool of recently obtained monoclonal antibodies directed against the recombinant 37LRP molecule was used to investigate the processing that leads to the formation of the 67-kDa molecule. In soluble extracts of A431 human carcinoma cells, these reagents recognize the precursor molecule as well as the mature 67LR and a 120-kDa molecule. The recovery of these proteins was found to be strikingly dependent upon the cell solubilization conditions: the 67LR is soluble in NP-40-lysis buffer whereas the 37LRP is NP-40-insoluble. Inhibition of 67LR formation by cerulenin indicates that acylation is involved in the processing of the receptor. It is likely a palmitoylation process, as indicated by sensitivity of NP-40-soluble extracts to hydroxylamine treatment. Immunoblotting assays performed with a polyclonal serum directed against galectin3 showed that both the 67- and the 120-kDa proteins carry galectin3 epitopes whereas the 37LRP does not. These data suggest that the 67LR is a heterodimer stabilized by strong intramolecular hydrophobic interactions, carried by fatty acids bound to the 37LRP and to a galectin3 cross-reacting molecule.

  1. Release of carrot plasma membrane-associated phosphatidylinositol kinase by phospholipase A2 and activation by a 70 kDa protein.

    PubMed

    Gross, W; Yang, W; Boss, W F

    1992-02-19

    Plasma membranes were isolated from carrot (Daucus carota L.) cells grown in suspension culture and treated with phospholipase A2 from snake or bee venom for 10 min. As a result of this treatment, phosphatidylinositol kinase activity was recovered in the soluble fraction. There was no detectable diacylglycerol kinase or phosphatidylinositol monophosphate kinase activity released from the membranes after the phospholipase A2 treatment. Treating the plasma membranes with phospholipase C or D did not release PI kinase activity. The phospholipase A2-released PI kinase was activated over 2-fold by a heat stable, soluble 70 kDa protein. The partially purified 70 kDa activator increases the Vmax but does not affect the Km of the phospholipase A2-released PI kinase.

  2. A 92-kDa human immunostimulatory protein.

    PubMed Central

    Fontan, E; Briend, E; Saklani-Jusforgues, H; d'Alayer, J; Vandekerckhove, J; Fauve, R M

    1994-01-01

    We purified to apparent homogeneity a human urinary glycoprotein of 92 kDa (HGP.92) that, administered intravenously at 250 micrograms/kg, fully protected mice against a lethal inoculum of Listeria monocytogenes. Since HGP.92 protected scid mice, which lack B and T lymphocytes, this increased resistance to Listeria did not appear to be lymphocyte mediated. Furthermore, inflammatory macrophages incubated with 6 nM HGP.92 inhibited the growth of Lewis carcinoma cells in vitro. These two activities appeared to depend on an oligosaccharide moiety, as they were lost after N-Glycanase treatment of HGP.92. Thus, the biological activity of HGP.92 was in some way related to a glycan moiety. Images PMID:8078887

  3. Characterization of a 65 kDa NIF in the nuclear matrix of the monocot Allium cepa that interacts with nuclear spectrin-like proteins.

    PubMed

    Pérez-Munive, Clara; Blumenthal, Sonal S D; de la Espina, Susana Moreno Díaz

    2012-01-01

    Plant cells have a well organized nucleus and nuclear matrix, but lack orthologues of the main structural components of the metazoan nuclear matrix. Although data is limited, most plant nuclear structural proteins are coiled-coil proteins, such as the NIFs (nuclear intermediate filaments) in Pisum sativum that cross-react with anti-intermediate filament and anti-lamin antibodies, form filaments 6-12 nm in diameter in vitro, and may play the role of lamins. We have investigated the conservation and features of NIFs in a monocot species, Allium cepa, and compared them with onion lamin-like proteins. Polyclonal antisera against the pea 65 kDa NIF were used in 1D and 2D Western blots, ICM (imunofluorescence confocal microscopy) and IEM (immunoelectron microscopy). Their presence in the nuclear matrix was analysed by differential extraction of nuclei, and their association with structural spectrin-like proteins by co-immunoprecipitation and co-localization in ICM. NIF is a conserved structural component of the nucleus and its matrix in monocots with Mr and pI values similar to those of pea 65 kDa NIF, which localized to the nuclear envelope, perichromatin domains and foci, and to the nuclear matrix, interacting directly with structural nuclear spectrin-like proteins. Its similarities with some of the proteins described as onion lamin-like proteins suggest that they are highly related or perhaps the same proteins.

  4. Selective affinity labeling of a 27-kDa integral membrane protein in rat liver and kidney with N-bromoacetyl derivatives of L-thyroxine and 3,5,3'-triiodo-L-thyronine.

    PubMed

    Köhrle, J; Rasmussen, U B; Rokos, H; Leonard, J L; Hesch, R D

    1990-04-15

    125I-Labeled N-bromoacetyl derivatives of L-thyroxine and L-triiodothyronine were used as alkylating affinity labels to identify rat liver and kidney microsomal membrane proteins which specifically bind thyroid hormones. Affinity label incorporation was analyzed by ethanol precipitation and individual affinity labeled proteins were identified by autoradiography after separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. Six to eight membrane proteins ranging in size from 17 to 84 kDa were affinity labeled by both bromoacetyl-L-thyroxine (BrAcT4) and bromoacetyl-L-triiodothyronine (BrAcT3). Affinity labeling was time- and temperature-dependent, and both reduced dithiols and detergents increased affinity labeling, predominantly in a 27-kDa protein(s). Up to 80% of the affinity label was associated with a 27-kDa protein (p27) under optimal conditions. Affinity labeling of p27 by 0.4 nM BrAc[125I]L-T4 was blocked by 0.1 microM of the alkylating ligands BrAcT4, BrAcT3, or 100 microM iodoacetate, by 10 microM concentrations of the non-alkylating, reversible ligands N-acetyl-L-thyroxine, 3,3',5'-triiodothyronine, 3,5-diiodosalicylate, and EMD 21388, a T4-antagonistic flavonoid. Neither 10 microM L-T4, nor 10 microM N-acetyltriiodothyronine or 10 microM L-triiodothyronine blocked affinity labeling of p27 or other affinity labeled bands. Affinity labeling of a 17-kDa band was partially inhibited by excess of the alkylating ligands BrAcT4, BrAcT3, and iodoacetate, but labeling of other minor bands was not blocked by excess of the competitors. BrAc[125I]T4 yielded higher affinity label incorporation than BrAc[125I]T3, although similar banding patterns were observed, except that BrAcT3 affinity labeled more intensely a 58,000-Da band in liver and a 53,000-55,000-Da band in kidney. The pattern of other affinity labeled proteins with p27 as the predominant band was similar in liver and kidney. Peptide mapping of affinity labeled p27

  5. Nup93, a Vertebrate Homologue of Yeast Nic96p, Forms a Complex with a Novel 205-kDa Protein and Is Required for Correct Nuclear Pore Assembly

    PubMed Central

    Grandi, Paola; Dang, Tam; Pané, Nelly; Shevchenko, Andrej; Mann, Matthias; Forbes, Douglass; Hurt, Ed

    1997-01-01

    Yeast and vertebrate nuclear pores display significant morphological similarity by electron microscopy, but sequence similarity between the respective proteins has been more difficult to observe. Herein we have identified a vertebrate nucleoporin, Nup93, in both human and Xenopus that has proved to be an evolutionarily related homologue of the yeast nucleoporin Nic96p. Polyclonal antiserum to human Nup93 detects corresponding proteins in human, rat, and Xenopus cells. Immunofluorescence and immunoelectron microscopy localize vertebrate Nup93 at the nuclear basket and at or near the nuclear entry to the gated channel of the pore. Immunoprecipitation from both mammalian and Xenopus cell extracts indicates that a small fraction of Nup93 physically interacts with the nucleoporin p62, just as yeast Nic96p interacts with the yeast p62 homologue. However, a large fraction of vertebrate Nup93 is extracted from pores and is also present in Xenopus egg extracts in complex with a newly discovered 205-kDa protein. Mass spectrometric sequencing of the human 205-kDa protein reveals that this protein is encoded by an open reading frame, KIAAO225, present in the human database. The putative human nucleoporin of 205 kDa has related sequence homologues in Caenorhabditis elegans and Saccharomyces cerevisiae. To analyze the role of the Nup93 complex in the pore, nuclei were assembled that lack the Nup93 complex after immunodepletion of a Xenopus nuclear reconstitution extract. The Nup93-complex–depleted nuclei are clearly defective for correct nuclear pore assembly. From these experiments, we conclude that the vertebrate and yeast pore have significant homology in their functionally important cores and that, with the identification of Nup93 and the 205-kDa protein, we have extended the knowledge of the nearest-neighbor interactions of this core in both yeast and vertebrates. PMID:9348540

  6. Nuclear 82-kDa choline acetyltransferase decreases amyloidogenic APP metabolism in neurons from APP/PS1 transgenic mice.

    PubMed

    Albers, Shawn; Inthathirath, Fatima; Gill, Sandeep K; Winick-Ng, Warren; Jaworski, Ewa; Wong, Daisy Y L; Gros, Robert; Rylett, R Jane

    2014-09-01

    Alzheimer disease (AD) is associated with increased amyloidogenic processing of amyloid precursor protein (APP) to β-amyloid peptides (Aβ), cholinergic neuron loss with decreased choline acetyltransferase (ChAT) activity, and cognitive dysfunction. Both 69-kDa ChAT and 82-kDa ChAT are expressed in cholinergic neurons in human brain and spinal cord with 82-kDa ChAT localized predominantly to neuronal nuclei, suggesting potential alternative functional roles for the enzyme. By gene microarray analysis, we found that 82-kDa ChAT-expressing IMR32 neural cells have altered expression of genes involved in diverse cellular functions. Importantly, genes for several proteins that regulate APP processing along amyloidogenic and non-amyloidogenic pathways are differentially expressed in 82-kDa ChAT-containing cells. The predicted net effect based on observed changes in expression patterns of these genes would be decreased amyloidogenic APP processing with decreased Aβ production. This functional outcome was verified experimentally as a significant decrease in BACE1 protein levels and activity and a concomitant reduction in the release of endogenous Aβ1-42 from neurons cultured from brains of AD-model APP/PS1 transgenic mice. The expression of 82-kDa ChAT in neurons increased levels of GGA3, which is involved in trafficking BACE1 to lysosomes for degradation. shRNA-induced decreases in GGA3 protein levels attenuated the 82-kDa ChAT-mediated decreases in BACE1 protein and activity and Aβ1-42 release. Evidence that 82-kDa ChAT can enhance GGA3 gene expression is shown by enhanced GGA3 gene promoter activity in SN56 neural cells expressing this ChAT protein. These studies indicate a novel relationship between cholinergic neurons and APP processing, with 82-kDa ChAT acting as a negative regulator of Aβ production. This decreased formation of Aβ could result in protection for cholinergic neurons, as well as protection of other cells in the vicinity that are sensitive to

  7. A DOUBLE KNOCKOUT; A NOVEL APPROACH TO UNDERSTANDING STRESS-INDUCIBLE 70 KDA HEAT SHOCK PROTEINS (HSP70S) ON DEVELOPMENT AND REPRODUCTION

    EPA Science Inventory

    Heat and chemical toxicants which disrupt spermatogenesis and cause male infertility are thought to induce the expression of Hsp70-1 and 70-3, the major inducible heat shock proteins of the 70kDa family. Previous studies from several laboratories including our own have characteri...

  8. Fed batch fermentation and purification strategy for high yield production of Brucella melitensis recombinant Omp 28 kDa protein and its application in disease diagnosis.

    PubMed

    Karothia, B S; Athmaram, T N; D, Thavaselvam; Ashu, Kumar; Tiwari, Sapna; Singh, Anil K; Sathyaseelan, K; Gopalan, N

    2013-07-01

    Brucellosis is a disease caused by bacteria belonging to the genus Brucella. It affects cattle, goat, sheep, dog and humans. The serodiagnosis of brucellosis involves detection of antibodies generated against the LPS or whole cell bacterial extracts, however these tests lack sensitivity and specificity. The present study was performed to optimize the culture condition for the production of recombinant Brucella melitensis outer membrane protein 28 kDa protein in E.coli via fed batch fermentation. Expression was induced with 1.5mM isopropyl β thiogalactoside and the expressed recombinant protein was purified using Ni-NTA affinity chromatography. After fed-batch fermentation the dry cell weight of 17.81 g/L and a purified protein yield of 210.10 mg/L was obtained. The purified Brucella melitensis recombinant Omp 28 kDa protein was analyzed through SDS- poly acrylamide gel electrophoresis and western blotting. The obtained recombinant protein was evaluated for its diagnostic application through Indirect ELISA using brucellosis suspected human sera samples. Our results clearly indicate that recombinant Omp28 produced via fed batch fermentation has immense potential as a diagnostic reagent that could be employed in sero monitoring of brucellosis.

  9. Allergenic Characterization of 27-kDa Glycoprotein, a Novel Heat Stable Allergen, from the Pupa of Silkworm, Bombyx mori.

    PubMed

    Jeong, Kyoung Yong; Son, Mina; Lee, June Yong; Park, Kyung Hee; Lee, Jae-Hyun; Park, Jung-Won

    2016-01-01

    Boiled silkworm pupa is a traditional food in Asia, and patients with silkworm pupa food allergy are common in these regions. Still now only one allergen from silkworm, arginine kinase, has been identified. The purpose of this study was to identify novel food allergens in silkworm pupa by analyzing a protein extract after heat treatment. Heat treated extracts were examined by proteomic analysis. A 27-kDa glycoprotein was identified, expressed in Escherichia coli, and purified. IgE reactivity of the recombinant protein was investigated by ELISA. High molecular weight proteins (above 100 kDa) elicited increased IgE binding after heat treatment compared to that before heat treatment. The molecular identities of these proteins, however, could not be determined. IgE reactivity toward a 27-kDa glycoprotein was also increased after heating the protein extract. The recombinant protein was recognized by IgE antibodies from allergic subjects (33.3%). Glycation or aggregation of protein by heating may create new IgE binding epitopes. Heat stable allergens are shown to be important in silkworm allergy. Sensitization to the 27-kDa glycoprotein from silkworm may contribute to elevation of IgE to silkworm.

  10. Allergenic Characterization of 27-kDa Glycoprotein, a Novel Heat Stable Allergen, from the Pupa of Silkworm, Bombyx mori

    PubMed Central

    Son, Mina; Lee, June Yong

    2016-01-01

    Boiled silkworm pupa is a traditional food in Asia, and patients with silkworm pupa food allergy are common in these regions. Still now only one allergen from silkworm, arginine kinase, has been identified. The purpose of this study was to identify novel food allergens in silkworm pupa by analyzing a protein extract after heat treatment. Heat treated extracts were examined by proteomic analysis. A 27-kDa glycoprotein was identified, expressed in Escherichia coli, and purified. IgE reactivity of the recombinant protein was investigated by ELISA. High molecular weight proteins (above 100 kDa) elicited increased IgE binding after heat treatment compared to that before heat treatment. The molecular identities of these proteins, however, could not be determined. IgE reactivity toward a 27-kDa glycoprotein was also increased after heating the protein extract. The recombinant protein was recognized by IgE antibodies from allergic subjects (33.3%). Glycation or aggregation of protein by heating may create new IgE binding epitopes. Heat stable allergens are shown to be important in silkworm allergy. Sensitization to the 27-kDa glycoprotein from silkworm may contribute to elevation of IgE to silkworm. PMID:26770033

  11. Two-dimensional polyacrylamide gel electrophoresis of equine seminal plasma proteins and their relation with semen freezability.

    PubMed

    Jobim, M I M; Trein, C; Zirkler, H; Gregory, R M; Sieme, H; Mattos, R C

    2011-09-01

    The objective was to evaluate protein profiles of equine seminal plasma using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and to determine whether any of these proteins were related to semen freezability. Seminal plasma was collected from 10 stallions, of high and low semen freezability, housed at the State Stud of Lower Saxony, and routinely used in AI programs. Twenty-five protein spots were identified from the two-dimensional gel (12%), seven of which were present in all samples (all proteins were identified by MALDI-MS). Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been used to generate ion images of samples in one or more mass-to-charge (m/z) values, providing the capability of mapping specific molecules to two-dimensional coordinates of the original sample. Of the 25 proteins identified, two spots had greater relative content (P < 0.05) in seminal plasma samples collected from stallions with high semen freezability: spot 5 (80-85 kDa, isoelectric point [pI] 7.54), identified as CRISP-3; and spot 45 (18.2 kDa, pI 5.0-5.2), identified as HSP-2. Conversely, protein content was greater (P < 0.05) in seminal plasma samples from stallions with low semen freezability: spot 7 (75.4 kDa, pI 6.9-7.4), identified as lactoferrin; spot 15 (26.7 kDa, pI 5.51), identified as kallikrein; spot 25 (25 kDa, pI 7.54), identified as CRISP-3; and spot 35 (13.9 kDa, pI 3.8-4.2), identified as HSP-1. In conclusion, there were differences in the seminal plasma protein profile from stallions with high and low semen freezability. Furthermore, CRISP-3 and HSP-2 were potential seminal plasma markers of high semen freezability. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. The plastid ribosomal proteins. Identification of all the proteins in the 30 S subunit of an organelle ribosome (chloroplast).

    PubMed

    Yamaguchi, K; von Knoblauch, K; Subramanian, A R

    2000-09-15

    Identification of all the protein components of a plastid (chloroplast) ribosomal 30 S subunit has been achieved, using two-dimensional gel electropholesis, high performance liquid chromatography purification, N-terminal sequencing, polymerase chain reaction-based screening of cDNA library, nucleotide sequencing, and mass spectrometry (electrospray ionization, matrix-assisted laser desorption/ionization time-of-flight, and reversed-phase HPLC coupled with electrospray ionization mass spectrometry). 25 proteins were identified, of which 21 are orthologues of all Escherichia coli 30 S ribosomal proteins (S1-S21), and 4 are plastid-specific ribosomal proteins (PSRPs) that have no homologues in the mitochondrial, archaebacterial, or cytosolic ribosomal protein sequences in data bases. 12 of the 25 plastid 30 S ribosomal proteins (PRPs) are encoded in the plastid genome, whereas the remaining 13 are encoded by the nuclear genome. Post-translational transit peptide cleavage sites for the maturation of the 13 cytosolically synthesized PRPs, and post-translational N-terminal processing in the maturation of the 12 plastid synthesized PRPs are described. Post-translational modifications in several PRPs were observed: alpha-N-acetylation of S9, N-terminal processings leading to five mature forms of S6 and two mature forms of S10, C-terminal and/or internal modifications in S1, S14, S18, and S19, leading to two distinct forms differing in mass and/or charge (the corresponding modifications are not observed in E. coli). The four PSRPs in spinach plastid 30 S ribosomal subunit (PSRP-1, 26.8 kDa, pI 6.2; PSRP-2, 21.7 kDa, pI 5.0; PSRP-3, 13.8 kDa, pI 4.9; PSRP-4, 5.2 kDa, pI 11.8) comprise 16% (67.6 kDa) of the total protein mass of the 30 S subunit (429.3 kDa). PSRP-1 and PSRP-3 show sequence similarities with hypothetical photosynthetic bacterial proteins, indicating their possible origins in photosynthetic bacteria. We propose the hypothesis that PSRPs form a "plastid

  13. Identification, characterization and purification to near-homogeneity of a novel 67 kDa phosphotyrosyl protein phosphatase associated with pig lung annexin extract.

    PubMed Central

    Vicendo, P; Fauvel, J; Ragab-Thomas, J M; Chap, H

    1991-01-01

    During the purification of annexin VI from pig lung, we previously reported the isolation of another 67 kDa protein (protein 67E) differing from the former by immunological reactivity, amino acid composition, inability to interact with anionic phospholipids in the presence of Ca2+ and inability to inhibit phospholipase A2 [Fauvel, Vicendo, Roques, Ragab-Thomas, Granier, Vilgrain, Chambaz, Rochat, Chap & Douste-Blazy (1987) FEBS Lett. 221, 397-402]. Attempts to phosphorylate protein 67E by the protein tyrosine kinase of epidermal-growth-factor receptor revealed a dramatic inhibition of receptor autophosphorylation, which was also observed with insulin receptor. This inhibitory effect was found to be supported by a phosphatase active towards p-nitrophenyl phosphate, phosphotyrosine, [32P]phosphotyrosyl histones and [32P]phosphotyrosyl poly(Glu,Tyr), but inactive towards phosphoserine, phosphothreonine and [32P]phosphoseryl histones. Although not purified to complete homogeneity, the enzyme was purified 273-fold over EGTA extracts from pig lung and corresponded to a monomeric protein displaying an apparent molecular mass of 67 kDa. With [32P]phosphotyrosyl poly(Glu,Tyr) as substrate, the purified enzyme displayed Km and Vmax. values of 10 microM and 1.93 mumol/min per mg respectively, which compare reasonably well with other recently described phosphotyrosyl protein phosphatases. From these data and from its sensitivity to various inhibitors, it is concluded that protein fraction 67E contains a novel phosphotyrosyl protein phosphatase, the association of which with annexin extract might offer a clue to the understanding of its possible targeting to membrane substrates. Images Fig. 1. Fig. 3. Fig. 5. PMID:1654882

  14. Microsporidia, amitochondrial protists, possess a 70-kDa heat shock protein gene of mitochondrial evolutionary origin.

    PubMed

    Peyretaillade, E; Broussolle, V; Peyret, P; Méténier, G; Gouy, M; Vivarès, C P

    1998-06-01

    An intronless gene encoding a protein of 592 amino acid residues with similarity to 70-kDa heat shock proteins (HSP70s) has been cloned and sequenced from the amitochondrial protist Encephalitozoon cuniculi (phylum Microsporidia). Southern blot analyses show the presence of a single gene copy located on chromosome XI. The encoded protein exhibits an N-terminal hydrophobic leader sequence and two motifs shared by proteobacterial and mitochondrially expressed HSP70 homologs. Phylogenetic analysis using maximum likelihood and evolutionary distances place the E. cuniculi sequence in the cluster of mitochondrially expressed HSP70s, with a higher evolutionary rate than those of homologous sequences. Similar results were obtained after cloning a fragment of the homologous gene in the closely related species E. hellem. The presence of a nuclear targeting signal-like sequence supports a role of the Encephalitozoon HSP70 as a molecular chaperone of nuclear proteins. No evidence for cytosolic or endoplasmic reticulum forms of HSP70 was obtained through PCR amplification. These data suggest that Encephalitozoon species have evolved from an ancestor bearing mitochondria, which is in disagreement with the postulated presymbiotic origin of Microsporidia. The specific role and intracellular localization of the mitochondrial HSP70-like protein remain to be elucidated.

  15. The 60 kDa heat shock proteins in the hyperthermophilic archaeon Sulfolobus shibatae.

    PubMed

    Kagawa, H K; Osipiuk, J; Maltsev, N; Overbeek, R; Quaite-Randall, E; Joachimiak, A; Trent, J D

    1995-11-10

    One of the most abundant proteins in the hyperthermophilic archaeon Sulfolobus shibatae is the 59 kDa heat shock protein (TF55) that is believed to form a homo-oligomeric double ring complex structurally similar to the bacterial chaperonins. We discovered a second protein subunit in the S. shibatae ring complex (referred to as alpha) that is stoichiometric with TF55 (renamed beta). The gene and flanking regions of alpha were cloned and sequenced and its inferred amino acid sequence has 54.4% identity and 74.4% similarity to beta. Transcription start sites for both alpha and beta were mapped and three potential transcription regulatory regions were identified. Northern analyses of cultures shifted from normal growth temperatures (70 to 75 degrees C) to heat shock temperatures (85 to 90 degrees C) indicated that the levels of alpha and beta mRNAs increased during heat shock, but at all temperatures their relative proportions remained constant. Monitoring protein synthesis by autoradiography of total proteins from cultures pulse labeled with L(-)[35S]methionine at normal and heat shock temperatures indicated significant increases in alpha and beta synthesis during heat shock. Under extreme heat shock conditions (> or = 90 degrees C) alpha and beta appeared to be the only two proteins synthesized. The purified alpha and beta subunits combined to form high molecular mass complexes with similar mobilities on native polyacrylamide gels to the complexes isolated directly from cells. Equal proportions of the two subunits gave the greatest yield of the complex, which we refer to as a "rosettasome". It is argued that the rosettasome consists of two homo-oligomeric rings; one of alpha and the other of beta. Polyclonal antibodies against alpha and beta from S. shibatae cross-reacted with proteins of similar molecular mass in 10 out of the 17 archaeal species tested, suggesting that the two rosettasome proteins are highly conserved among the archaea. The archaeal sequences were

  16. Baculovirus-vectored multistage Plasmodium vivax vaccine induces both protective and transmission-blocking immunities against transgenic rodent malaria parasites.

    PubMed

    Mizutani, Masanori; Iyori, Mitsuhiro; Blagborough, Andrew M; Fukumoto, Shinya; Funatsu, Tomohiro; Sinden, Robert E; Yoshida, Shigeto

    2014-10-01

    A multistage malaria vaccine targeting the pre-erythrocytic and sexual stages of Plasmodium could effectively protect individuals against infection from mosquito bites and provide transmission-blocking (TB) activity against the sexual stages of the parasite, respectively. This strategy could help prevent malaria infections in individuals and, on a larger scale, prevent malaria transmission in communities of endemicity. Here, we describe the development of a multistage Plasmodium vivax vaccine which simultaneously expresses P. vivax circumsporozoite protein (PvCSP) and P25 (Pvs25) protein of this species as a fusion protein, thereby acting as a pre-erythrocytic vaccine and a TB vaccine, respectively. A new-concept vaccine platform based on the baculovirus dual-expression system (BDES) was evaluated. The BDES-Pvs25-PvCSP vaccine displayed correct folding of the Pvs25-PvCSP fusion protein on the viral envelope and was highly expressed upon transduction of mammalian cells in vitro. This vaccine induced high levels of antibodies to Pvs25 and PvCSP and elicited protective (43%) and TB (82%) efficacies against transgenic P. berghei parasites expressing the corresponding P. vivax antigens in mice. Our data indicate that our BDES, which functions as both a subunit and DNA vaccine, can offer a promising multistage vaccine capable of delivering a potent antimalarial pre-erythrocytic and TB response via a single immunization regimen. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  17. Oleosins (24 and 18 kDa) are hydrolyzed not only in extracted soybean oil bodies but also in soybean germination.

    PubMed

    Chen, Yeming; Zhao, Luping; Cao, Yanyun; Kong, Xiangzhen; Hua, Yufei

    2014-01-29

    After oil bodies (OBs) were extracted from ungerminated soybean by pH 6.8 extraction, it was found that 24 and 18 kDa oleosins were hydrolyzed in the extracted OBs, which contained many OB extrinsic proteins (i.e., lipoxygenase, β-conglycinin, γ-conglycinin, β-amylase, glycinin, Gly m Bd 30K (Bd 30K), and P34 probable thiol protease (P34)) as well as OB intrinsic proteins. In this study, some properties (specificity, optimal pH and temperature) of the proteases of 24 and 18 kDa oleosins and the oleosin hydrolysis in soybean germination were examined, and the high relationship between Bd 30K/P34 and the proteases was also discussed. The results showed (1) the proteases were OB extrinsic proteins, which had high specificity to hydrolyze 24 and 18 kDa oleosins, and cleaved the specific peptide bonds to form limited hydrolyzed products; (2) 24 and 18 kDa oleosins were not hydrolyzed in the absence of Bd 30K and P34 (or some Tricine-SDS-PAGE undetectable proteins); (3) the protease of 24 kDa oleosin had strong resistance to alkaline pH while that of 18 kDa oleosin had weak resistance to alkaline pH, and Bd 30K and P34, resolved into two spots on two-dimensional electrophoresis gel, also showed the same trend; (4) 16 kDa oleosin as well as 24 and 18 kDa oleosins were hydrolyzed in soybean germination, and Bd 30K and P34 were always contained in the extracted OBs from germinated soybean even when all oleosins were hydrolyzed; (5) the optimal temperature and pH of the proteases were respectively determined as in the ranges of 35-50 °C and pH 6.0-6.5, while 60 °C or pH 11.0 could denature them.

  18. Uptake of oleate by isolated rat adipocytes is mediated by a 40-kDa plasma membrane fatty acid binding protein closely related to that in liver and gut

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schwieterman, W.; Sorrentino, D.; Potter, B.J.

    1988-01-01

    A portion of the hepatocellular uptake of nonesterified long-chain fatty acids is mediated by a specific 40-kDa plasma membrane fatty acid binding protein, which has also been isolated from the gut. To investigate whether a similar transport process exists in other tissues with high transmembrane fatty acid fluxes, initial rates (V/sub O/) of (/sup 3/H)-oleate uptake into isolated rat adipocytes were studied as a function of the concentration of unbound (/sup 3/H)oleate in the medium. V/sub O/ reached a maximum as the concentration of unbound oleate was increased and was significantly inhibited both by phloretin and by prior incubation ofmore » the cells with Pronase. A rabbit antibody to the rat liver plasma membrane fatty acid binding protein inhibited adipocyte fatty acid uptake by up to 63% in dose-dependent fashion. Inhibition was noncompetitive; at an immunoglobulin concentration of 250 ..mu..g/ml V/sub max/ was reduced from 2480 /plus minus/ 160 to 1870 /plus minus/ 80 pmol/min per 5 /times/ 10/sup 4/ adipocytes, with no change in K/sub m/. A basic kDa adipocyte plasma membrane fatty acid binding protein, isolated from crude adipocyte plasma membrane fractions, reacted strongly in both agar gel diffusion and electrophoretic blots with the antibody raised against the corresponding hepatic plasma membrane protein. These data indicate that the uptake of oleate by rat adipocytes is mediated by a 40-kDa plasma membrane fatty acid binding protein closely related to that in liver and gut.« less

  19. Verification of Faulty Message Passing Systems with Continuous State Space in PVS

    NASA Technical Reports Server (NTRS)

    Pilotto, Concetta; White, Jerome

    2010-01-01

    We present a library of Prototype Verification System (PVS) meta-theories that verifies a class of distributed systems in which agent commu nication is through message-passing. The theoretic work, outlined in, consists of iterative schemes for solving systems of linear equations , such as message-passing extensions of the Gauss and Gauss-Seidel me thods. We briefly review that work and discuss the challenges in formally verifying it.

  20. Ultrahigh-Resolution Differential Ion Mobility Separations of Conformers for Proteins above 10 kDa: Onset of Dipole Alignment?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shvartsburg, Alexandre A.

    2014-11-04

    Biomacromolecules tend to assume numerous structures in solution or the gas phase. It has been possible to resolve disparate conformational families but not unique geometries within each, and drastic peak broadening has been the bane of protein analyses by chromatography, electrophoresis, and ion mobility spectrometry (IMS). The new differential IMS (FAIMS) approach using hydrogen-rich gases was recently found to separate conformers of a small protein ubiquitin with same peak width and resolving power up to ~400 as for peptides. Present work explores the reach of this approach for larger proteins, exemplified by cytochrome c and myoglobin. Resolution similar to thatmore » for ubiquitin was largely achieved with longer separations, while the onset of peak broadening and coalescence with shorter separations suggests the limitation of present technique to proteins under ~20 kDa. This capability may enable distinguishing whole proteins with differing residue sequences or localizations of posttranslational modifications. Small features at negative compensation voltages that markedly grow from cytochrome c to myoglobin indicate the dipole alignment of rare conformers in accord with theory, further supporting the concept of pendular macroions in FAIMS.« less

  1. Crucial role of neuron-enriched endosomal protein of 21 kDa in sorting between degradation and recycling of internalized G-protein-coupled receptors.

    PubMed

    Debaigt, Colin; Hirling, Harald; Steiner, Pascal; Vincent, Jean-Pierre; Mazella, Jean

    2004-08-20

    Recycling of endocytosed G-protein-coupled receptors involves a series of molecular events through early and recycling endosomes. The purpose of this work was to study the role of neuron-enriched endosomal protein of 21 kDa (NEEP21) in the recycling process of neurotensin receptors-1 and -2. Here we showed that suppression of NEEP21 expression does not modify the internalization rate of both receptors but strongly inhibited the recycling of the neurotensin receptor-2. In contrast, overexpression of NEEP21 changes the behavior of the neurotensin receptor-1 from a non-recycling to a recycling state. Recycling of the neurotensin receptor-2 involves both the phosphatidylinositol 3-kinase and the recycling endosome pathways, whereas recycling of the neurotensin receptor-1 induced by overexpression of NEEP21 only occurs by the phosphatidylinositol 3-kinase-dependent pathway. Taken together, these results confirm the essential role of NEEP21 in the recycling mechanism and show that this protein acts at the level of early endosomes to promote sorting of receptors toward a recycling pathway.

  2. A study of over 35,000 women with breast cancer tested with a 25-gene panel of hereditary cancer genes.

    PubMed

    Buys, Saundra S; Sandbach, John F; Gammon, Amanda; Patel, Gayle; Kidd, John; Brown, Krystal L; Sharma, Lavania; Saam, Jennifer; Lancaster, Johnathan; Daly, Mary B

    2017-05-15

    As panel testing becomes more common in clinical practice, it is important to understand the prevalence and trends associated with the pathogenic variants (PVs) identified. This is especially true for genetically heterogeneous cancers, such as breast cancer (BC), in which PVs in different genes may be associated with various risks and cancer subtypes. The authors evaluated the outcomes of genetic testing among women who had a personal history of BC. A total of 35,409 women with a single diagnosis of BC who underwent clinical genetic testing with a 25-gene panel were included in the current analysis. Women with multiple BCs and men with BC were excluded. The frequency and distribution of PVs were assessed for the overall cohort, among women with triple-negative BC (TNBC) (n = 4797), and by age at diagnosis. PVs were identified in 9.3% of women tested; 51.5% of PVs were identified in genes other than breast cancer 1 (BRCA1) and BRCA2, including checkpoint kinase 2 (CHEK2) (11.7%), ataxia telangiectasia mutated (ATM; ATM serine/threonine kinase) (9.7%), and partner and localizer of BRCA2 (PALB2) (9.3%). The prevalence of PVs in BRCA1, PALB2, BRCA1-associated RING domain 1 (BARD1), BRCA1-interacting protein C-terminal helicase 1 (BRIP1), and RAD51 paralog C (RAD51C) was statistically higher among women with TNBC. The PV rate was higher among women aged <40 years, lower among women aged >59 years, and relatively constant (8.5%-9.0%) among women who were diagnosed between ages 40 and 59 years. These results demonstrate that panel testing increased the number of women identified as carrying a PV in this cohort compared with BRCA testing alone. Furthermore, the proportion of women identified who carried a PV in this cohort did not decrease between ages 40 and 59 years. Cancer 2017;123:1721-1730. © 2017 American Cancer Society. © 2017 American Cancer Society.

  3. Calmyonemin: a 23 kDa analogue of algal centrin occurring in contractile myonemes of Eudiplodinium maggii (ciliate).

    PubMed

    David, C; Viguès, B

    1994-01-01

    Myonemes are bundles of thin filaments (3-6 nm in diameter) which mediate calcium-induced contraction of the whole or only parts of the cell body in a number of protists. In Eudiplodinium maggii, a rumen ciliate which lacks a uniform ciliation of the cell body, myonemes converge toward the bases of apical ciliary zones that can be retracted under stress conditions, entailing immobilization of the cell. An mAB (A69) has been produced that identifies a calcium-binding protein by immunoblot, immunoprecipitation experiments and specifically labels the myonemes in immunoelectron microscopy. Solubility properties, apparent molecular weight (23 kDa) and isoelectric point (4.9) of the myonemal protein, are similar to the values reported for the calcium-modulated contractile protein centrin. Western-blot analysis indicates that the 23 kDa protein cross-reacts antigenically with anti-centrin antibodies. In addition, the 23 kDa protein displays calcium-induced changes in both electrophoretic and chromatographic behaviour, and contains calcium-binding domains that conform to the EF-hand structure, as known for centrin. Based on these observations, we conclude that a calcium-binding protein with major similarities to centrin occurs in the myonemes of E. maggii. We postulate that this protein plays an essential role in myoneme-mediated retraction of the ciliature.

  4. The oviducal protein, heat-shock 70-kDa protein 8, improves the long-term survival of ram spermatozoa during storage at 17°C in a commercial extender.

    PubMed

    Lloyd, R E; Fazeli, A; Watson, P F; Holt, W V

    2012-01-01

    Poor fertility rates are often observed when fresh ram semen stored in conventional extenders is used for cervical artificial insemination (AI). Heat-shock 70-kDa protein 8 (HSPA8), found within the oviduct, prolongs boar, ram and bull sperm survival at body temperatures in vitro. Here, we aimed to determine whether supplementing extenders (INRA-96 and RSD-1) with HSPA8 (4 µg mL⁻¹) would improve their performance in maintaining freshly collected ram sperm viability and sperm nuclear DNA integrity during storage over 48 h at 17°C. Sperm function was assessed at 1, 6, 24 and 48h and this experiment was repeated using 25 × 10⁶ and 800 × 10⁶ spermatozoa mL⁻¹. INRA96 supplemented with HSPA8 maintained sperm viability significantly better than INRA96 alone at both sperm concentrations. However, sperm nuclear DNA fragmentation (DF) increased significantly during storage using the higher sperm concentration, irrespective of the extender and the protein treatment used. Increasing levels of sperm nuclear DF over time could explain why poor fertility rates are often observed following cervical AI using stored ram semen. However, further research is required to ascertain whether supplementing the commercially available INRA96 extender with HSPA8 will improve fertility rates following cervical AI using stored ram semen.

  5. Transcriptional activation of a 37 kDa ethylene responsive cysteine protease gene, RbCP1, is associated with protein degradation during petal abscission in rose

    PubMed Central

    Tripathi, Siddharth Kaushal; Singh, Amar Pal; Sane, Aniruddha P.; Nath, Pravendra

    2009-01-01

    Cysteine proteases play an important role in several developmental processes in plants, particularly those related to senescence and cell death. A cysteine protease gene, RbCP1, has been identified that encodes a putative protein of 357 amino acids and is expressed in the abscission zone (AZ) of petals in rose. The gene was responsive to ethylene in petals, petal abscission zones, leaves, and thalamus. The expression of RbCP1 increased during both ethylene-induced as well as natural abscission and was inhibited by 1-MCP. Transcript accumulation of RbCP1 was accompanied by the appearance of a 37 kDa cysteine protease, a concomitant increase in protease activity and a substantial decrease in total protein content in the AZ of petals. Agro-injection of rose petals with a 2.0 kb region upstream of the RbCP1 gene could drive GUS expression in an abscission zone-specific manner and was blocked by 1-MCP. It is concluded that petal abscission is associated with a decrease in total protein content resulting from rapid transcription of RbCP1 and the expression of a 37 kDa protease. PMID:19346241

  6. Diagnostic potential of Fasciola gigantica-derived 14.5 kDa fatty acid binding protein in the immunodiagnosis of bubaline fascioliasis.

    PubMed

    Allam, G; Bauomy, I R; Hemyeda, Z M; Diab, T M; Sakran, T F

    2013-06-01

    The 14.5 kDa fatty acid binding protein (FABP) was isolated from the crude extract of adult Fasciola gigantica worms. Polyclonal anti-FABP IgG was generated in rabbits immunized with prepared FABP antigen. Sandwich enzyme-linked immunosorbent assay (ELISA) was applied to detect coproantigen in stools and circulating Fasciola antigen (CA) in sera of 126 water buffaloes by using purified and horseradish peroxidase (HRP)-conjugated anti-FABP IgG. Sandwich ELISA sensitivity was 96.97% and 94.95%; while specificity was 94.12% and 82.35% for coproantigen and CA detection, respectively. However, sensitivity and specificity of the Kato-Katz technique was 73.74% and 100%, respectively. The diagnostic efficacy of sandwich ELISA was 96.55% and 93.1% for coproantigen and CA detection, respectively. In contrast, the diagnostic efficacy of the Kato-Katz technique was 77.59%. In conclusion, these results demonstrate that the purified 14.5 kDa FABP provides a more suitable antigen for immunodiagnosis of early and current bubaline fascioliasis by using sandwich ELISA.

  7. Maize arabinoxylan gels as protein delivery matrices.

    PubMed

    Berlanga-Reyes, Claudia M; Carvajal-Millán, Elizabeth; Lizardi-Mendoza, Jaime; Rascón-Chu, Agustin; Marquez-Escalante, Jorge A; Martínez-López, Ana Luisa

    2009-04-08

    The laccase induced gelation of maize bran arabinoxylans at 2.5% (w/v) in the presence of insulin or beta-lactoglobulin at 0.1% (w/v) was investigated. Insulin and beta-lacto-globulin did not modify either the gel elasticity (9 Pa) or the cross-links content (0.03 and 0.015 microg di- and triferulic acids/mg arabinoxylan, respectively). The protein release capability of the gel was also investigated. The rate of protein release from gels was dependent on the protein molecular weight. The apparent diffusion coefficient was 0.99 x 10(-7) and 0.79 x 10(-7) cm(2)/s for insulin (5 kDa) and beta-lactoglobulin (18 kDa), respectively. The results suggest that maize bran arabinoxylan gels can be potential candidates for the controlled release of proteins.

  8. Characterization of a small (25-kilodalton) derivative of the Rous sarcoma virus Gag protein competent for particle release.

    PubMed Central

    Weldon, R A; Wills, J W

    1993-01-01

    Retroviral Gag proteins have the ability to induce budding and particle release from the plasma membrane when expressed in the absence of all of the other virus-encoded components; however, the locations of the functional domains within the Gag protein that are important for this process are poorly understood. It was shown previously that the protease sequence of the Rous sarcoma virus (RSV) Gag protein can be replaced with a foreign polypeptide, iso-1-cytochrome c from a yeast, without disrupting particle assembly (R. A. Weldon, Jr., C. R. Erdie, M. G. Oliver, and J. W. Wills, J. Virol. 64:4169-4179, 1990). An unexpected product of the chimeric gag gene is a small, Gag-related protein named p25C. This product was of interest because of its high efficiency of packaging into particles. The goal of the experiments described here was to determine the mechanism by which p25C is synthesized and packaged into particles. The results demonstrate that it is not the product of proteolytic processing of the Gag-cytochrome precursor but is derived from an unusual spliced mRNA. cDNA clones of the spliced mRNA were obtained, and each expressed a product of approximately 25 kDa, designated p25M1, which was released into the growth medium in membrane-enclosed particles that were much lighter than authentic retrovirions as measured in sucrose density gradients. DNA sequencing revealed that the clones encode the first 180 of the 701 amino acids of the RSV Gag protein and no residues from iso-1-cytochrome c. This suggested that a domain in the carboxy-terminal half of Gag is important for the packaging of Gag proteins into dense arrays within the particles. In support of this hypothesis, particles of the correct density were obtained when a small segment from the carboxy terminus of the RSV Gag protein (residues 417 to 584) was included on the end of p25. Images PMID:8394460

  9. Evaluation of a Plasmodium-Specific Carrier Protein To Enhance Production of Recombinant Pfs25, a Leading Transmission-Blocking Vaccine Candidate.

    PubMed

    Parzych, Elizabeth M; Miura, Kazutoyo; Ramanathan, Aarti; Long, Carole A; Burns, James M

    2018-01-01

    Challenges with the production and suboptimal immunogenicity of malaria vaccine candidates have slowed the development of a Plasmodium falciparum multiantigen vaccine. Attempting to resolve these issues, we focused on the use of highly immunogenic merozoite surface protein 8 (MSP8) as a vaccine carrier protein. Previously, we showed that a genetic fusion of the C-terminal 19-kDa fragment of merozoite surface protein 1 (MSP1 19 ) to P. falciparum MSP8 ( Pf MSP8) facilitated antigen production and folding and the induction of neutralizing antibodies to conformational B cell epitopes of MSP1 19 Here, using the Pf MSP1/8 construct, we further optimized the recombinant Pf MSP8 (r Pf MSP8) carrier by the introduction of two cysteine-to-serine substitutions (CΔS) to improve the yield of the monomeric product. We then sought to test the broad applicability of this approach using the transmission-blocking vaccine candidate Pf s25. The production of r Pf s25-based vaccines has presented challenges. Antibodies directed against the four highly constrained epidermal growth factor (EGF)-like domains of Pf s25 block sexual-stage development in mosquitoes. The sequence encoding mature Pf s25 was codon harmonized for expression in Escherichia coli We produced a r Pf s25- Pf MSP8 fusion protein [r Pf s25/8(CΔS)] as well as unfused, mature r Pf s25. r Pf s25 was purified with a modest yield but required the incorporation of refolding protocols to obtain a proper conformation. In comparison, chimeric r Pf s25/8(CΔS) was expressed and easily purified, with the Pf s25 domain bearing the proper conformation without renaturation. Both antigens were immunogenic in rabbits, inducing IgG that bound native Pf s25 and exhibited potent transmission-reducing activity. These data further demonstrate the utility of Pf MSP8 as a parasite-specific carrier protein to enhance the production of complex malaria vaccine targets. Copyright © 2017 American Society for Microbiology.

  10. Purification and characterization of a 22-kDa microsomal protein from rat parotid gland which is phosphorylated following stimulation by agonists involving cAMP as second messenger.

    PubMed

    Thiel, G; Schmidt, W E; Meyer, H E; Söling, H D

    1988-01-04

    Stimulation of secretion in exocrine glands by agonists involving cAMP as second messenger leads to the phosphorylation of the ribosomal protein S6 (protein I) and two other particulate proteins with apparent molecular masses of 24 kDa (protein II) and 22 kDa (protein III) [Jahn, R., Unger, C. & Söling, H. D. (1980) Eur. J. Biochem. 112, 345-352]. This report describes the purification and characterization of protein III. Solubilization studies indicate that protein III is an intrinsic membrane protein. It could be extracted from the endoplasmic reticulum membrane only with Triton X-100, SDS or concentrated formic or acetic acid. The purification of this protein involved extraction of the microsomes with Triton X-100, removal of the detergent by acetone precipitation, extraction of water-soluble proteins, lipids and lipoproteins, and preparative SDS polyacrylamide gel electrophoresis. The protein has a basic pI (greater than 8.7). For determination of the amino acid composition of protein III and for sequencing of its amino-terminal portion, the protein was electroeluted out off the gel, the detergent removed and the protein finally purified by reversed-phase HPLC. Protein III could be phosphorylated in vitro by the catalytic subunit of the cAMP-dependent protein kinase to a degree of approximately 0.14 mol phosphate/mol protein. The only phosphopeptide obtained after in vitro phosphorylation and subsequent tryptic or chymotryptic digestion was identical with the phosphopeptide obtained after stimulation of intact rat parotid gland lobules with isoproterenol. The sequence of this peptide was Lys-Leu-Ser(P)-Glu-Ala-Asp-Asn-Arg. It was confirmed by an analysis of the synthetic peptide following in vitro phosphorylation with cAMP-dependent protein kinase. The first 41 N-terminal residues of protein III were sequenced. So far no sequence homology with other known peptides or proteins could be found.

  11. RNAi silenced Dd-grp94 (Dictyostelium discoideum glucose-regulated protein 94 kDa) cell lines in Dictyostelium exhibit marked reduction in growth rate and delay in development.

    PubMed

    Baviskar, Sandhya N; Shields, Malcolm S

    2010-01-01

    Glucose-regulated 94 kDa protein (Grp94) is a resident of the endoplasmic reticulum (ER) of multicellular eukaryotes. It is a constitutively expressed protein that is overexpressed in certain abnormal conditions of the cell such as depletion of glucose and calcium, and low oxygen and pH. The protein is also implicated in diseased conditions like cancer and Alzheimer's disease. In this study, the consequences of downregulation of Grp94 were investigated at both unicellular and multicellular stages of Dictyostelium discoideum. Previous studies have shown the expression of Dd-Grp94 (Dictyostelium discoideum glucose-regulated 94 kDa protein) in wild-type cells varies during development, and overexpression of Dd-Grp94 leads to abnormal cell shape and inhibition of development (i.e., formation of fruiting bodies). Grp94 is a known calcium binding protein and an efficient calcium buffer. Therefore, in the present study we hypothesized that downregulation of Dd-Grp94 protein would affect Dictyostelium cell structure, growth, and development. We found that Dd-grp94 RNAi recombinants exhibited reduced growth rate, cell size, and a subtle change in cell motility compared to the parental cells. The recombinants also exhibited a delay in development and small fruiting bodies. These results establish that Dd-grp94 plays a crucial role in determining normal cell structure, growth and differentiation.

  12. Cloning and sequencing of a gene encoding the 69-kDa extracellular chitinase of Janthinobacterium lividum.

    PubMed

    Gleave, A P; Taylor, R K; Morris, B A; Greenwood, D R

    1995-09-15

    Janthinobacterium lividum secretes a major 56-kDa chitinase and a minor 69-kDa chitinase. A chitinase gene was defined on a 3-kb fragment of clone pRKT10, by virtue of fluorescent colonies in the presence of 4-methylumbelliferyl-beta-D-N,N',N"-chitotrioside. Nucleotide sequencing revealed an 1998-bp open reading frame with the potential to encode a 69,716-Da protein with amino acid sequences similar to those in other chitinases, suggesting it encodes the minor chitinase (Chi69). Chitinase activity of Escherichia coli (pRKT10) lysates was detected mainly in the periplasmic fraction and immunoblotting detected a 70-kDa protein in this fraction. Chi69 has an N-terminal secretory leader peptide preceding two probable chitin-binding domains and a catalytic domain. These functional domains are separated by linker regions of proline-threonine repeats. Amino acid sequencing of cyanogen bromide cleavage-derived peptides from the major 56-kDa chitinase suggested that Chi69 may be a precursor of Chi56. In addition, an N-terminally truncated version of Chi69 retained chitinase activity as expected if in vivo processing of Chi69 generates Chi56.

  13. Buffalo Cheese Whey Proteins, Identification of a 24 kDa Protein and Characterization of Their Hydrolysates: In Vitro Gastrointestinal Digestion.

    PubMed

    Bassan, Juliana C; Goulart, Antonio J; Nasser, Ana L M; Bezerra, Thaís M S; Garrido, Saulo S; Rustiguel, Cynthia B; Guimarães, Luis H S; Monti, Rubens

    2015-01-01

    Milk whey proteins are well known for their high biological value and versatile functional properties, characteristics that allow its wide use in the food and pharmaceutical industries. In this work, a 24 kDa protein from buffalo cheese whey was analyzed by mass spectrometry and presented homology with Bos taurus beta-lactoglobulin. In addition, the proteins present in buffalo cheese whey were hydrolyzed with pepsin and with different combinations of trypsin, chymotrypsin and carboxypeptidase-A. When the TNBS method was used the obtained hydrolysates presented DH of 55 and 62% for H1 and H2, respectively. Otherwise for the OPA method the DH was 27 and 43% for H1 and H2, respectively. The total antioxidant activities of the H1 and H2 samples with and without previous enzymatic hydrolysis, determined by DPPH using diphenyl-p-picrylhydrazyl radical, was 4.9 and 12 mM of Trolox equivalents (TE) for H2 and H2Dint, respectively. The increased concentrations for H1 and H2 samples were approximately 99% and 75%, respectively. The in vitro gastrointestinal digestion efficiency for the samples that were first hydrolyzed was higher compared with samples not submitted to previous hydrolysis. After in vitro gastrointestinal digestion, several amino acids were released in higher concentrations, and most of which were essential amino acids. These results suggest that buffalo cheese whey is a better source of bioavailable amino acids than bovine cheese whey.

  14. Buffalo Cheese Whey Proteins, Identification of a 24 kDa Protein and Characterization of Their Hydrolysates: In Vitro Gastrointestinal Digestion

    PubMed Central

    Bassan, Juliana C.; Goulart, Antonio J.; Nasser, Ana L. M.; Bezerra, Thaís M. S.; Garrido, Saulo S.; Rustiguel, Cynthia B.; Guimarães, Luis H. S.; Monti, Rubens

    2015-01-01

    Milk whey proteins are well known for their high biological value and versatile functional properties, characteristics that allow its wide use in the food and pharmaceutical industries. In this work, a 24 kDa protein from buffalo cheese whey was analyzed by mass spectrometry and presented homology with Bos taurus beta-lactoglobulin. In addition, the proteins present in buffalo cheese whey were hydrolyzed with pepsin and with different combinations of trypsin, chymotrypsin and carboxypeptidase-A. When the TNBS method was used the obtained hydrolysates presented DH of 55 and 62% for H1 and H2, respectively. Otherwise for the OPA method the DH was 27 and 43% for H1 and H2, respectively. The total antioxidant activities of the H1 and H2 samples with and without previous enzymatic hydrolysis, determined by DPPH using diphenyl-p-picrylhydrazyl radical, was 4.9 and 12 mM of Trolox equivalents (TE) for H2 and H2Dint, respectively. The increased concentrations for H1 and H2 samples were approximately 99% and 75%, respectively. The in vitro gastrointestinal digestion efficiency for the samples that were first hydrolyzed was higher compared with samples not submitted to previous hydrolysis. After in vitro gastrointestinal digestion, several amino acids were released in higher concentrations, and most of which were essential amino acids. These results suggest that buffalo cheese whey is a better source of bioavailable amino acids than bovine cheese whey. PMID:26465145

  15. Heat shock 70-kDa protein 8 isoform 1 is expressed on the surface of human embryonic stem cells and downregulated upon differentiation.

    PubMed

    Son, Yeon Sung; Park, Jae Hyun; Kang, Young Kook; Park, Jin-Sung; Choi, Hong Seo; Lim, Ji Young; Lee, Jeoung Eun; Lee, Jung Bok; Ko, Myoung Seok; Kim, Yong-Sam; Ko, Jeong-Heon; Yoon, Hyun Soo; Lee, Kwang-Woong; Seong, Rho Hyun; Moon, Shin Yong; Ryu, Chun Jeih; Hong, Hyo Jeong

    2005-01-01

    The cell-surface markers used routinely to define the undifferentiated state and pluripotency of human embryonic stem cells (hESCs) are those used in mouse embryonic stem cells (mESCs) because of a lack of markers directly originated from hESC itself. To identify more hESC-specific cell-surface markers, we generated a panel of monoclonal antibodies (MAbs) by immunizing the irradiated cell clumps of hESC line Miz-hES1, and selected 26 MAbs that were able to bind to Miz-hES1 cells but not to mESCs, mouse embryonic fibroblast cells, and STO cells. Most antibodies did not bind to human neural progenitor cells derived from the Miz-hES1 cells, either. Of these, MAb 20-202S (IgG1, kappa) immunoprecipitated a cell-surface protein of 72-kDa from the lysate of biotin-labeled Miz-hES1 cells, which was identified to be heat shock 70-kDa protein 8 isoform 1 (HSPA8) by quadrupole time-of-flight tandem mass spectrometry. Immunocytochemical analyses proved that the HSPA8 protein was also present on the surface of hESC lines Miz-hES4, Miz-hES6, and HSF6. Two-color flow cytometric analysis of Miz-hES1 and HSF6 showed the coexpression of the HSPA8 protein with other hESC markers such as stage-specific embryonic antigen 3 (SSEA3), SSEA4, TRA-1-60, and TRA-1-81. Flow cytometric and Western blot analyses using various cells showed that MAb 20-202S specifically bound to the HSPA8 protein on the surface of Miz-hES1, contrary to other anti-HSP70 antibodies examined. Furthermore, the surface expression of the HSPA8 protein on Miz-hES1 was markedly downregulated upon differentiation. These data indicate that a novel MAb 20-202S recognizes the HSPA8 protein on the surface of hESCs and suggest that the HSPA8 protein is a putative cell-surface marker for undifferentiated hESCs.

  16. Cloning of habutobin cDNA and antithrombotic activity of recombinant protein

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sunagawa, Masanori; Nakamura, Mariko; Kosugi, Tadayoshi

    2007-11-03

    The habutobin cDNA was cloned from total RNA extracted from venom glands of Trimeresurus flavoviridis (the habu snake). The conceptual translation of 1539 bp of habutobin cDNA consists of 236 amino acids and its molecular weight is 25.7 kDa. Histidine (His)-tagged recombinant habutobin fusion protein, pET-r-habutobin and AcNPV-r-habutobin, was purified by bacterial system and baculoviral system, respectively. After refolding pET-r-habutobin, there were two protein bands at about 32 kDa and 65 kDa, indicating that habutobin might be produced as a monomer protein and processed to form two concatenated protein. Purified AcNPV-r-habutobin dose-dependently increased fibrin forming activity and inhibited collagen-induced aggregationmore » of rabbit washed platelets. Thus, AcNPV-r-habutobin produced by baculoviral system is very useful for study on structure-function relationship, which is necessary for developing an antithrombotic drug from habutobin.« less

  17. Thermodynamic analysis of the disorder-to-α-helical transition of 18.5-kDa myelin basic protein reveals an equilibrium intermediate representing the most compact conformation.

    PubMed

    Vassall, Kenrick A; Jenkins, Andrew D; Bamm, Vladimir V; Harauz, George

    2015-05-22

    The intrinsically disordered, 18.5-kDa isoform of myelin basic protein (MBP) is a peripheral membrane protein that is essential to proper myelin formation in the central nervous system. MBP acts in oligodendrocytes both to adjoin membrane leaflets to each other in forming myelin and as a hub in numerous protein-protein and protein-membrane interaction networks. Like many intrinsically disordered proteins (IDPs), MBP multifunctionality arises from its high conformational plasticity and its ability to undergo reversible disorder-to-order transitions. One such transition is the disorder-to-α-helical conformational change that is induced upon MBP-membrane binding. Here, we have investigated the disorder-to-α-helical transition of MBP-derived α-peptides and the full-length 18.5-kDa protein. This transition was induced through titration of the membrane-mimetic solvent trifluoroethanol into both protein and peptide solutions, and conformational change was monitored using circular dichroism spectroscopy, 1-anilinonaphthalene-8-sulfonic acid binding, tryptophan fluorescence quenching, and Förster (fluorescence) resonance energy transfer measurements. The data suggest that the disorder-to-α-helical transition of MBP follows a 3-state model: disordered↔intermediate↔α-helical, with each of the identified equilibrium states likely representing a conformational ensemble. The disordered state is characterized by slight compaction with little regular secondary structure, whereas the intermediate is also disordered but globally more compact. Surprisingly, the α-helical conformation is less compact than the intermediate. This study suggests that multifunctionality in MBP could arise from differences in the population of energetically distinct ensembles under different conditions and also provides an example of an IDP that undergoes cooperative global conformation change. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Expression, purification, and characterization of a bifunctional 99-kDa peptidoglycan hydrolase from Pediococcus acidilactici ATCC 8042.

    PubMed

    García-Cano, Israel; Campos-Gómez, Manuel; Contreras-Cruz, Mariana; Serrano-Maldonado, Carlos Eduardo; González-Canto, Augusto; Peña-Montes, Carolina; Rodríguez-Sanoja, Romina; Sánchez, Sergio; Farrés, Amelia

    2015-10-01

    Pediococcus acidilactici ATCC 8042 is a lactic acid bacteria that inhibits pathogenic microorganisms such as Staphylococcus aureus through the production of two proteins with lytic activity, one of 110 kDa and the other of 99 kDa. The 99-kDa one has high homology to a putative peptidoglycan hydrolase (PGH) enzyme reported in the genome of P. acidilactici 7_4, where two different lytic domains have been identified but not characterized. The aim of this work was the biochemical characterization of the recombinant enzyme of 99 kDa. The enzyme was cloned and expressed successfully and retains its activity against Micrococcus lysodeikticus. It has a higher N-acetylglucosaminidase activity, but the N-acetylmuramoyl-L-alanine amidase can also be detected spectrophotometrically. The protein was then purified using gel filtration chromatography. Antibacterial activity showed an optimal pH of 6.0 and was stable between 5.0 and 7.0. The optimal temperature for activity was 60 °C, and all activity was lost after 1 h of incubation at 70 °C. The number of strains susceptible to the recombinant 99-kDa enzyme was lower than that susceptible to the mixture of the 110- and 99-kDa PGHs of P. acidilactici, a result that suggests synergy between these two enzymes. This is the first PGH from LAB that has been shown to possess two lytic sites. The results of this study will aid in the design of new antibacterial agents from natural origin that can combat foodborne disease and improve hygienic practices in the industrial sector.

  19. 16 kDa heat shock protein from heat-inactivated Mycobacterium tuberculosis is a homodimer - suitability for diagnostic applications with specific llama VHH monoclonals.

    PubMed

    Srivastava, Saurabh K; Ruigrok, Vincent J B; Thompson, Natalie J; Trilling, Anke K; Heck, Albert J R; van Rijn, Cees; Beekwilder, Jules; Jongsma, Maarten A

    2013-01-01

    The 16 kDa heat shock protein (HSP) is an immuno-dominant antigen, used in diagnosis of infectious Mycobacterium tuberculosis (M.tb.) causing tuberculosis (TB). Its use in serum-based diagnostics is limited, but for the direct identification of M.tb. bacteria in sputum or cultures it may represent a useful tool. Recently, a broad set of twelve 16 kDa specific heavy chain llama antibodies (VHH) has been isolated, and their utility for diagnostic applications was explored. To identify the epitopes recognized by the nine (randomly selected from a set of twelve 16 kDa specific VHH antibodies) distinct VHH antibodies, 14 overlapping linear epitopes (each 20 amino acid long) were characterized using direct and sandwich ELISA techniques. Seven out of 14 epitopes were recognized by 8 out of 9 VHH antibodies. The two highest affinity binders B-F10 and A-23 were found to bind distinct epitopes. Sandwich ELISA and SPR experiments showed that only B-F10 was suitable as secondary antibody with both B-F10 and A-23 as anchoring antibodies. To explain this behavior, the epitopes were matched to the putative 3D structure model. Electrospray ionization time-of-flight mass spectrometry and size exclusion chromatography were used to determine the higher order conformation. A homodimer model best explained the differential immunological reactivity of A-23 and B-F10 against heat-treated M.tb. lysates. The concentrations of secreted antigens of M.tb. in sputum are too low for immunological detection and existing kits are only used for identifying M.tb. in cultures. Here we describe how specific combinations of VHH domains could be used to detect the intracellular HSP antigen. Linked to methods of pre-concentrating M.tb. cells prior to lysis, HSP detection may enable the development of protein-based diagnostics of sputum samples and earlier diagnosis of diseases.

  20. Lower glutamic acid decarboxylase 65-kDa isoform messenger RNA and protein levels in the prefrontal cortex in schizoaffective disorder but not schizophrenia.

    PubMed

    Glausier, Jill R; Kimoto, Sohei; Fish, Kenneth N; Lewis, David A

    2015-01-15

    Altered gamma-aminobutyric acid (GABA) signaling in the prefrontal cortex (PFC) has been associated with cognitive dysfunction in patients with schizophrenia and schizoaffective disorder. Levels of the GABA-synthesizing enzyme glutamic acid decarboxylase 67-kDa isoform (GAD67) in the PFC have been consistently reported to be lower in patients with these disorders, but the status of the second GABA-synthesizing enzyme, glutamic acid decarboxylase 65-kDa isoform (GAD65), remains unclear. GAD65 messenger RNA (mRNA) levels were quantified in PFC area 9 by quantitative polymerase chain reaction from 62 subjects with schizophrenia or schizoaffective disorder and 62 matched healthy comparison subjects. In a subset of subject pairs, GAD65 relative protein levels were quantified by confocal immunofluorescence microscopy. Mean GAD65 mRNA levels were 13.6% lower in subjects with schizoaffective disorder but did not differ in subjects with schizophrenia relative to their matched healthy comparison subjects. In the subjects with schizoaffective disorder, mean GAD65 protein levels were 19.4% lower and were correlated with GAD65 mRNA levels. Lower GAD65 mRNA and protein levels within subjects with schizoaffective disorder were not attributable to factors commonly comorbid with the diagnosis. In concert with previous studies, these findings suggest that schizoaffective disorder is associated with lower levels of both GAD65 and GAD67 mRNA and protein in the PFC, whereas subjects with schizophrenia have lower mean levels of only GAD67 mRNA and protein. Because cognitive function is generally better preserved in patients with schizoaffective disorder relative to patients with schizophrenia, these findings may support an interpretation that GAD65 downregulation provides a homeostatic response complementary to GAD67 downregulation that serves to reduce inhibition in the face of lower PFC network activity. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc

  1. Trichinella spiralis: strong antibody response to a 49 kDa newborn larva antigen in infected rats.

    PubMed

    Salinas-Tobon, Maria Del Rosario; Navarrete-Leon, Anaid; Mendez-Loredo, Blanca Esther; Esquivel-Aguirre, Dalia; Martínez-Abrajan, Dulce Maria; Hernandez-Sanchez, Javier

    2007-02-01

    In this work, we analyzed the kinetics of anti-Trichinella spiralis newborn larva (NBL) antibodies (Ab) and the antigenic recognition pattern of NBL proteins and its dose effects. Wistar rats were infected with 0, 700, 2000, 4000 and 8000 muscle larvae (ML) and bled at different time intervals up to day 31 post infection (p.i.). Ab production was higher with 2000 ML dose and decreased with 8000, 4000 and 700 ML. Abs were not detected until day 10, peaked on day 14 for the 2000 ML dose and on day 19 for the other doses and thereafter declined slowly from 19 to 31 days p.i. In contrast, Abs to ML increased from day 10, peaked on day 19 and remained high until the end of the study. Abs bound strongly at least to three NBL components of 188, 205 and 49 kDa. NBL antigen of 188 and 205 kDa were recognized 10-26 days p.i. and that of 49 kDa from day 10 to day 31 p.i. A weak recognition towards antigens of 52, 54, 62 and 83 kDa was also observed during the infection. An early recognition of 31, 43, 45, 55, 68 and 85 kDa ML antigens was observed whereas the response to those of 43, 45, 48, 60, 64 and 97 kDa (described previously as TSL-1 antigens) occurred late in the infection. A follow-up of antigen recognition up to day 61 with the optimal immunization dose (2000 ML) evidenced a decline of Ab production to the 49 kDa NBL antigen 42 days p.i., which suggested antigenic differences with the previously reported 43 kDa ML antigen strongly recognized late in the infection. To analyze the stage-specificity of the 49 kDa NBL antigen, polyclonal antibodies (PoAb) were obtained in rats immunized with 49 kDa NBL antigen. PoAb reacted strongly with the 49 kDa NBL component in NBL total soluble extract but no reactivity was observed with soluble antigen of the other T. spiralis stages. Albeit with less intensity, the 49 kDa component was also recognized by PoAb together with other antigens of 53, 97 and 107 kDa, in NBL excretory-secretory products (NBL-ESP). Thus, our results reveal

  2. Channel Formation by CarO, the Carbapenem Resistance-Associated Outer Membrane Protein of Acinetobacter baumannii

    PubMed Central

    Siroy, Axel; Molle, Virginie; Lemaître-Guillier, Christelle; Vallenet, David; Pestel-Caron, Martine; Cozzone, Alain J.; Jouenne, Thierry; Dé, Emmanuelle

    2005-01-01

    It has been recently shown that resistance to both imipenem and meropenem in multidrug-resistant clinical strains of Acinetobacter baumannii is associated with the loss of a heat-modifiable 25/29-kDa outer membrane protein, called CarO. This study aimed to investigate the channel-forming properties of CarO. Mass spectrometry analyses of this protein band detected another 25-kDa protein (called Omp25), together with CarO. Both proteins presented similar physicochemical parameters (Mw and pI). We overproduced and purified the two polypeptides as His-tagged recombinant proteins. Circular dichroism analyses demonstrated that the secondary structure of these proteins was mainly a β-strand conformation with spectra typical of porins. We studied the channel-forming properties of proteins by reconstitution into artificial lipid bilayers. In these conditions, CarO induced ion channels with a conductance value of 110 pS in 1 M KCl, whereas the Omp25 protein did not form any channels, despite its suggested porin function. The pores formed by CarO showed a slight cationic selectivity and no voltage closure. No specific imipenem binding site was found in CarO, and this protein would rather form unspecific monomeric channels. PMID:16304148

  3. ZP Domain Proteins in the Abalone Egg Coat Include a Paralog of VERL under Positive Selection That Binds Lysin and 18-kDa Sperm Proteins

    PubMed Central

    Aagaard, Jan E.; Vacquier, Victor D.; MacCoss, Michael J.; Swanson, Willie J.

    2010-01-01

    Identifying fertilization molecules is key to our understanding of reproductive biology, yet only a few examples of interacting sperm and egg proteins are known. One of the best characterized comes from the invertebrate archeogastropod abalone (Haliotis spp.), where sperm lysin mediates passage through the protective egg vitelline envelope (VE) by binding to the VE protein vitelline envelope receptor for lysin (VERL). Rapid adaptive divergence of abalone lysin and VERL are an example of positive selection on interacting fertilization proteins contributing to reproductive isolation. Previously, we characterized a subset of the abalone VE proteins that share a structural feature, the zona pellucida (ZP) domain, which is common to VERL and the egg envelopes of vertebrates. Here, we use additional expressed sequence tag sequencing and shotgun proteomics to characterize this family of proteins in the abalone egg VE. We expand 3-fold the number of known ZP domain proteins present within the VE (now 30 in total) and identify a paralog of VERL (vitelline envelope zona pellucida domain protein [VEZP] 14) that contains a putative lysin-binding motif. We find that, like VERL, the divergence of VEZP14 among abalone species is driven by positive selection on the lysin-binding motif alone and that these paralogous egg VE proteins bind a similar set of sperm proteins including a rapidly evolving 18-kDa paralog of lysin, which may mediate sperm–egg fusion. This work identifies an egg coat paralog of VERL under positive selection and the candidate sperm proteins with which it may interact during abalone fertilization. PMID:19767347

  4. Heat-shock protein-25/27 phosphorylation by the delta isoform of protein kinase C.

    PubMed Central

    Maizels, E T; Peters, C A; Kline, M; Cutler, R E; Shanmugam, M; Hunzicker-Dunn, M

    1998-01-01

    Small heat-shock proteins (sHSPs) are widely expressed 25-28 kDa proteins whose functions are dynamically regulated by phosphorylation. While recent efforts have clearly delineated a stress-responsive p38 mitogen-activated protein-kinase (MAPK)-dependent kinase pathway culminating in activation of the heat-shock (HSP)-kinases, mitogen-activated protein-kinase-activated protein kinase-2 and -3, not all sHSP phosphorylation events can be explained by the p38 MAPK-dependent pathway. The contribution of protein kinase C (PKC) to sHSP phosphorylation was suggested by early studies but later questioned on the basis of the reported poor ability of purified PKC to phosphorylate sHSP in vitro. The current study re-evaluates the role of PKC in sHSP phosphorylation in the light of the isoform complexity of the PKC family. We evaluated the sHSP phosphorylation status in rat corpora lutea obtained from two stages of pregnancy, mid-pregnancy and late-pregnancy, which express different levels of the novel PKC isoform, PKC-delta. Two-dimensional Western blot analysis showed that HSP-27 was more highly phosphorylated in vivo in corpora lutea of late pregnancy, corresponding to the developmental stage in which PKC-delta is abundant and active. Late-pregnant luteal extracts contained a lipid-sensitive HSP-kinase activity which exactly co-purified with PKC-delta using hydroxyapatite and S-Sepharose column chromatography. To determine whether there might be preferential phosphorylation of sHSP by a particular PKC isoform, purified recombinant PKC isoforms corresponding to those PKC isoforms detected in rat corpora lutea were evaluated for HSP-kinase activity in vitro. Recombinant PKC-delta effectively catalysed the phosphorylation of sHSP in vitro, and PKC-alpha was 30-50% as effective as an HSP-kinase; other PKCs tested (beta1, beta2, epsilon and zeta) were poor HSP-kinases. These results show that select PKC family members can function as direct HSP-kinases in vitro. Moreover, the

  5. The expression of a novel stress protein '150-kDa oxygen regulated protein' in sudden infant death.

    PubMed

    Ikematsu, Kazuya; Tsuda, Ryouichi; Kondo, Toshikazu; Kondo, Hisayoshi; Ozawa, Kentaro; Ogawa, Satoshi; Nakasono, Ichiro

    2003-03-01

    The oxygen regulated protein 150-kDa (ORP-150) is only induced in hypoxic conditions. We performed an immunohistochemical and morphometrical study on the expression of ORP-150 in the brains of sudden infant death (SID) victims. The cerebral cortexes of 18 infants were used for this study. Each tissue section was incubated with anti-ORP-150 polyclonal antibodies and the number of ORP-150 positive cells was counted. In the cluster analysis, the 18 cases were classified into three groups (A-C groups). Group A was composed of six sudden infant death syndrome (SIDS) cases and its mean value of ORP-150 positive cells was 66.75+/-3.44, Group B (six severe respiratory infectious disease such as pneumonia and bronchitis including sepsis): 39.50+/-2.52 and Group C (five SIDS and one severe respiratory infectious disease): 16.00+/-2.92, respectively. These results might reflect chronic hypoxic condition before death, because ORP-150 is only induced when a hypoxic condition exist, but not acute hypoxia. And chronic hypoxic state is likely to be antecedent to SIDS. Therefore, immunohistochemical analysis of OPR-150 in the brain of SID cases may be very useful to differentiate between SIDS and acute asphyxia.

  6. Purification and Immunobiochemical Characterization of a 31 kDa Cross-Reactive Allergen from Phaseolus vulgaris (Kidney Bean)

    PubMed Central

    Kasera, Ramkrashan; Singh, Anand Bahadur; Lavasa, Shakuntala; Nagendra, Komarla; Arora, Naveen

    2013-01-01

    Background Legumes are a rich source of proteins but are also potential elicitors of IgE-mediated food allergy. This study aimed to isolate and characterize a major allergen of Phaseolus vulgaris (kidney bean) and determine its allergenicity. Methodology Kidney bean allergen was purified using Q Sepharose column (anion exchanger) and eluates with high intensity were pooled to purify protein using Superdex 75 (gel filtration) and C18 column (RP-HPLC). Patients with history of kidney bean allergy were skin prick tested (SPT) with crude kidney bean extract and the purified protein. Specific IgE was estimated in sera by enzyme-linked immunosorbent assay (ELISA). Characterization of purified protein and its cross-reactivity was investigated by immunobiochemical methods. Identification of purified protein was carried out by tandem mass spectrometry. Principal Findings Purified protein appeared as a single band at 31 kDa on SDS-PAGE and showed IgE binding to 88% patients’ sera by ELISA and immunoblotting. SPT with purified protein identified 78% hypersensitive patients of kidney bean. Significant release of histamine from sensitized basophils was observed after challenge with purified protein. PAS staining suggested it to be a glycoprotein, but no change in IgE binding was observed after periodate oxidation. The 31 kDa protein remained stable for 60 min on incubation with pepsin. The purified protein had high allergenic potential since it required only 102 ng of self protein for 50% IgE inhibition. Mass spectrometric analysis identified it as Phytohemagglutinin. It also showed hemagglutination with human RBCs. Cross-reactivity was observed with peanut and black gram with IC50 of 185 and 228 ng respectively. Conclusion/Significance A 31 kDa major allergen of kidney bean was purified and identified as phytohemagglutinin with cross-reactivity to peanut and black gram. PMID:23671655

  7. Chemical and biological activities of a 64-kilodalton outer sheath protein from Treponema denticola strains.

    PubMed Central

    Weinberg, A; Holt, S C

    1991-01-01

    This study examined the distribution of the major outer sheath proteins (MOSP) in several Treponema denticola strains and reports the isolation of a 64-kDa protein from the outer sheath of human clinical isolate T. denticola GM-1. The outer sheath was isolated by freeze-thaw procedures, and the distribution of outer sheath proteins was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). T. denticola GM-1, MS25, SR-5, and three low-passage clinical isolates possessed an MOSP with a relative molecular mass of 60 to 64 kDa. This MOSP was absent in T. denticola ATCC 35404 (TD-4) and clinical isolate SR-4. The latter possessed an MOSP of 58 kDa. 125I labeling revealed both MOSP to be dissociated forms of higher-molecular-mass oligomeric units between 116 and 162 kDa. Two-dimensional SDS-PAGE confirmed the modifiability of these MOSP. Isoelectric focusing of the 64-kDa MOSP indicated a pI of 6.7. Immunoblots with antiserum to GM-1 whole cells revealed the 64-kDa protein to be immunogenic and not cross-reactive with the MOSP of TD-4 or SR-4, and monospecific antibody to the 64-kDa protein recognized common epitopes on the high-molecular-weight oligomeric protein. These antibodies did not react with any component of TD-4 whole cells in immunoblots or in immunogold electron microscopy. Fab fragments inhibited the adherence of T. denticola GM-1 to human gingival fibroblasts by 78% (1:1,600; 0.72 micrograms of protein per ml), while TD-4 adherence was not inhibited. Amino acid analysis revealed a slightly acidic protein, devoid of cysteine, with 36% hydrophobic residues. Cyanogen bromide fragmentation of the 64-kDa protein revealed that a 42-kDa fragment contained a T-L-D-L-A-L-D segment which was 100% homologous with an integrin alpha subunit of a human leukocyte adhesion glycoprotein p 150,95. Images FIG. 1 FIG. 2 FIG. 3 FIG. 4 FIG. 5 FIG. 6 FIG. 7 FIG. 8 FIG. 9 FIG. 10 FIG. 11 FIG. 12 FIG. 13 FIG. 14 PMID:1938897

  8. Heat shock protein 47 and 65-kDa FK506-binding protein weakly but synergistically interact during collagen folding in the endoplasmic reticulum.

    PubMed

    Ishikawa, Yoshihiro; Holden, Paul; Bächinger, Hans Peter

    2017-10-20

    Collagen is the most abundant protein in the extracellular matrix in humans and is critical to the integrity and function of many musculoskeletal tissues. A molecular ensemble comprising more than 20 molecules is involved in collagen biosynthesis in the rough endoplasmic reticulum. Two proteins, heat shock protein 47 (Hsp47/ SERPINH1 ) and 65-kDa FK506-binding protein (FKBP65/ FKBP10 ), have been shown to play important roles in this ensemble. In humans, autosomal recessive mutations in both genes cause similar osteogenesis imperfecta phenotypes. Whereas it has been proposed that Hsp47 and FKBP65 interact in the rough endoplasmic reticulum, there is neither clear evidence for this interaction nor any data regarding their binding affinities for each other. In this study using purified endogenous proteins, we examined the interaction between Hsp47, FKBP65, and collagen and also determined their binding affinities and functions in vitro Hsp47 and FKBP65 show a direct but weak interaction, and FKBP65 prefers to interact with Hsp47 rather than type I collagen. Our results suggest that a weak interaction between Hsp47 and FKBP65 confers mutual molecular stability and also allows for a synergistic effect during collagen folding. We also propose that Hsp47 likely acts as a hub molecule during collagen folding and secretion by directing other molecules to reach their target sites on collagens. Our findings may explain why osteogenesis imperfecta-causing mutations in both genes result in similar phenotypes. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  9. Initial assessment of strategic plans for improving the performance of veterinary services in developing countries: a review of OIE PVS gap analysis reports.

    PubMed

    Weaver, J; Leon, E; Edan, M; D'Alessio, F

    2012-08-01

    The World Organisation for Animal Health (OIE) carries out Gap Analysis missions (if a country so wishes) as part of its programme to assess and improve the Performance of Veterinary Services (the 'PVS Pathway') in Member Countries. These Gap Analysis missions have found that many national Veterinary Services comply to only a limited extent with the international standards established by the OIE and that their competence is compromised by poor governance. This failure threatens animal and public health not only nationally but also internationally. The OIE PVS Gap Analysis reports reviewed found that all the Veterinary Services have a strong vision and commitmentto improvement but are held back by a weak chain of command, inadequate and outdated legislation, insufficient funding, weak technical competencies, compromised technical independence, poor communications and limited joint programmes. There are weaknesses across all the core technical areas of trade, animal health, veterinary public health and veterinary laboratories and also in the overall management of the Veterinary Services. The OIE PVS Gap Analysis missions recommend significant increases in budget in all countries.

  10. Genomic position affects the expression of tobacco mosaic virus movement and coat protein genes.

    PubMed Central

    Culver, J N; Lehto, K; Close, S M; Hilf, M E; Dawson, W O

    1993-01-01

    Alterations in the genomic position of the tobacco mosaic virus (TMV) genes encoding the 30-kDa cell-to-cell movement protein or the coat protein greatly affected their expression. Higher production of 30-kDa protein was correlated with increased proximity of the gene to the viral 3' terminus. A mutant placing the 30-kDa open reading frame 207 nucleotides nearer the 3' terminus produced at least 4 times the wild-type TMV 30-kDa protein level, while a mutant placing the 30-kDa open reading frame 470 nucleotides closer to the 3' terminus produced at least 8 times the wild-type TMV 30-kDa protein level. Increases in 30-kDa protein production were not correlated with the subgenomic mRNA promoter (SGP) controlling the 30-kDa gene, since mutants with either the native 30-kDa SGP or the coat protein SGP in front of the 30-kDa gene produced similar levels of 30-kDa protein. Lack of coat protein did not affect 30-kDa protein expression, since a mutant with the coat protein start codon removed did not produce increased amounts of 30-kDa protein. Effects of gene positioning on coat protein expression were examined by using a mutant containing two different tandemly positioned tobamovirus (TMV and Odontoglossum ringspot virus) coat protein genes. Only coat protein expressed from the gene positioned nearest the 3' viral terminus was detected. Analysis of 30-kDa and coat protein subgenomic mRNAs revealed no proportional increase in the levels of mRNA relative to the observed levels of 30-kDa and coat proteins. This suggests that a translational mechanism is primarily responsible for the observed effect of genomic position on expression of 30-kDa movement and coat protein genes. Images Fig. 2 Fig. 3 Fig. 4 PMID:8446627

  11. Photoactivable analogs for labeling 25-hydroxyvitamin D3 serum binding protein and for 1,25-dihydroxyvitamin D3 intestinal receptor protein

    NASA Technical Reports Server (NTRS)

    Kutner, A.; Link, R. P.; Schnoes, H. K.; DeLuca, H. F.

    1986-01-01

    3-Azidobenzoates and 3-azidonitrobenzoates of 25-hydroxyvitamin D3 as well as 3-deoxy-3-azido-25-hydroxyvitamin D3 and 3-deoxy-3-azido-1,25-dihydroxyvitamin D3 were prepared as photoaffinity labels for vitamin D serum binding protein and 1,25-dihydroxyvitamin D3 intestinal receptor protein. The compounds prepared were easily activated by short- or long-wavelength uv light, as monitored by uv and ir spectrometry. The efficacy of the compounds to compete with 25-hydroxyvitamin D3 or 1,25-dihydroxyvitamin D3 for the binding site of serum binding protein and receptor, respectively, was studied to evaluate the vitamin D label with the highest affinity for the protein. The presence of an azidobenzoate or azidonitrobenzoate substituent at the C-3 position of 25-OH-D3 significantly decreased (10(4)- to 10(6)-fold) the binding activity. However, the labels containing the azido substituent attached directly to the vitamin D skeleton at the C-3 position showed a high affinity, only 20- to 150-fold lower than that of the parent compounds with their respective proteins. Therefore, 3-deoxy-3-azidovitamins present potential ligands for photolabeling of vitamin D proteins and for studying the structures of the protein active sites.

  12. Protein 4.1 and its interaction with other cytoskeletal proteins in Xenopus laevis oogenesis.

    PubMed

    Carotenuto, Rosa; Petrucci, Tamara C; Correas, Isabel; Vaccaro, Maria C; De Marco, Nadia; Dale, Brian; Wilding, Martin

    2009-06-01

    In human red blood cells, protein 4.1 (4.1R) is an 80-kDa polypeptide that stabilizes the spectrin-actin network and anchors it to the plasma membrane. In non-erythroid cells there is a great variety of 4.1R isoforms, mainly generated by alternative pre-mRNA splicing, which localize at various intracellular sites, including the nucleus. We studied protein 4.1R distribution in relation to beta-spectrin, actin and cytokeratin during Xenopus oogenesis. Immunoprecipitation experiments indicate that at least two isoforms of protein 4.1R are present in Xenopus laevis oocytes: a 56-kDa form in the cytoplasm and a 37-kDa form in the germinal vesicle (GV). Antibodies to beta-spectrin reveal two bands of 239 and 100 kDa in the cytoplasm. Coimmunoprecipitation experiments indicate that both the 37- and 56-kDa isoforms of protein 4.1R associate with the 100-kDa isoform of beta-spectrin. Moreover, the 56-kDa form coimmunoprecipitates with a cytokeratin of the same molecular weight. Confocal immunolocalization shows that protein 4.1R distribution is in the peripheral cytoplasm, in the mitochondrial cloud (MC) and in the GV of previtellogenic oocytes. In the cytoplasm of vitellogenic oocytes, a loose network of fibers stained by the anti-protein 4.1R antibody spreads across the cytoplasm. beta-Spectrin has a similar distribution. Protein 4.1R was found to colocalize with actin in the cortex of oocytes in the form of fluorescent dots. Double immunolocalization of protein 4.1R and cytokeratin depicts two separate networks that overlap throughout the whole cytoplasm. Protein 4.1R filaments partially colocalize with cytokeratin in both the animal and vegetal hemispheres. We hypothesize that protein 4.1R could function as a linker protein between cytokeratin and the actin-based cytoskeleton.

  13. The 33.1 kDa Excretory/secretory Protein Produced by Toxocara canis Larvae Serves as a Potential Common Biomarker for Serodiagnosis of Toxocariasis in Paratenic Animals and Human.

    PubMed

    Nguyen, Huu-Hung; Vo, Doan-Trung; Thai, Thi-Tuyet-Trinh; LE, Thi-Thanh-Thao; LE, Thanh-Dong; Hoang, Nghia-Son

    2017-01-01

    Toxocariasis is a prevalent zoonosis disease caused by the closely related nematode species Toxocara canis and Toxocara cati which parasitise Canidae and Felidae respectively. In paratenic hosts, larvae of these worms cause multiple organ damage. However, how these paratenic hosts response to these worms and whether any common biomarker can be applied for diagnosis are still unclear. Excreted/secreted (E/S) antigens were prepared by culture of T. canis larvae in vitro. Using a western blot (WB) assay the humoral IgG responses, induced by Toxocara spp. larvae to the worm's E/S antigens in different infected hosts including mice, rabbits and human, were examined. In a mouse model of toxocariasis, intraperitoneal injection of T. canis larvae induces inflammatory leukocyte accumulation in the liver and the lungs but not in the brain, although a remarkable number of larvae were detected in this organ. Mice and rabbits responded differently to Toxocara spp. resulting in distinct heterogenous WB band patterns. Mice and rabbits both responded to a 33.1 kDa E/S constituent that turned out to be the most sensitive protein for serodiagnosis. Sera from human toxocariasis patients showed heterogenous WB band patterns similar to those observed in rabbits and all responded to the 33.1 kDa band. 33.1 kDa E/S protein can be considered as a critical common biomarker for toxocariasis immuno-diagnosis in both paratenic animals and human and its specificity requires further investigation.

  14. The 33.1 kDa Excretory/secretory Protein Produced by Toxocara canis Larvae Serves as a Potential Common Biomarker for Serodiagnosis of Toxocariasis in Paratenic Animals and Human

    PubMed Central

    NGUYEN, Huu-Hung; VO, Doan-Trung; THAI, Thi-Tuyet-Trinh; LE, Thi-Thanh-Thao; LE, Thanh-Dong; HOANG, Nghia-Son

    2017-01-01

    Background: Toxocariasis is a prevalent zoonosis disease caused by the closely related nematode species Toxocara canis and Toxocara cati which parasitise Canidae and Felidae respectively. In paratenic hosts, larvae of these worms cause multiple organ damage. However, how these paratenic hosts response to these worms and whether any common biomarker can be applied for diagnosis are still unclear. Methods: Excreted/secreted (E/S) antigens were prepared by culture of T. canis larvae in vitro. Using a western blot (WB) assay the humoral IgG responses, induced by Toxocara spp. larvae to the worm’s E/S antigens in different infected hosts including mice, rabbits and human, were examined. Results: In a mouse model of toxocariasis, intraperitoneal injection of T. canis larvae induces inflammatory leukocyte accumulation in the liver and the lungs but not in the brain, although a remarkable number of larvae were detected in this organ. Mice and rabbits responded differently to Toxocara spp. resulting in distinct heterogenous WB band patterns. Mice and rabbits both responded to a 33.1 kDa E/S constituent that turned out to be the most sensitive protein for serodiagnosis. Sera from human toxocariasis patients showed heterogenous WB band patterns similar to those observed in rabbits and all responded to the 33.1 kDa band. Conclusion: 33.1 kDa E/S protein can be considered as a critical common biomarker for toxocariasis immuno-diagnosis in both paratenic animals and human and its specificity requires further investigation. PMID:28761463

  15. Evolutionary and structural analyses of alpha-papillomavirus capsid proteins yields novel insights into L2 structure and interaction with L1

    PubMed Central

    Lowe, John; Panda, Debasis; Rose, Suzanne; Jensen, Ty; Hughes, Willie A; Tso, For Yue; Angeletti, Peter C

    2008-01-01

    Background PVs (PV) are small, non-enveloped, double-stranded DNA viruses that have been identified as the primary etiological agent for cervical cancer and their potential for malignant transformation in mucosal tissue has a large impact on public health. The PV family Papillomaviridae is organized into multiple genus based on sequential parsimony, host range, tissue tropism, and histology. We focused this analysis on the late gene products, major (L1) and minor (L2) capsid proteins from the family Papillomaviridae genus Alpha-papillomavirus. Alpha-PVs preferentially infect oral and anogenital mucosa of humans and primates with varied risk of oncogenic transformation. Development of evolutionary associations between PVs will likely provide novel information to assist in clarifying the currently elusive relationship between PV and its microenvironment (i.e., the single infected cell) and macro environment (i.e., the skin tissue). We attempt to identify the regions of the major capsid proteins as well as minor capsid proteins of alpha-papillomavirus that have been evolutionarily conserved, and define regions that are under constant selective pressure with respect to the entire family of viruses. Results This analysis shows the loops of L1 are in fact the most variable regions among the alpha-PVs. We also identify regions of L2, involved in interaction with L1, as evolutionarily conserved among the members of alpha- PVs. Finally, a predicted three-dimensional model was generated to further elucidate probable aspects of the L1 and L2 interaction. PMID:19087355

  16. Type I allergy to elderberry (Sambucus nigra) is elicited by a 33.2 kDa allergen with significant homology to ribosomal inactivating proteins.

    PubMed

    Förster-Waldl, E; Marchetti, M; Schöll, I; Focke, M; Radauer, C; Kinaciyan, T; Nentwich, I; Jäger, S; Schmid, E R; Boltz-Nitulescu, G; Scheiner, O; Jensen-Jarolim, E

    2003-12-01

    Patients suffering from allergic rhinoconjunctivitis and dyspnoea during summer may exhibit these symptoms after contact with flowers or dietary products of the elderberry tree Sambucus nigra. Patients with a history of summer hayfever were tested in a routine setting for sensitization to elderberry. Nine patients having allergic symptoms due to elderberry and specific sensitization were investigated in detail. We studied the responsible allergens in extracts from elderberry pollen, flowers and berries, and investigated cross-reactivity with allergens from birch, grass and mugwort. Sera from patients were tested for IgE reactivity to elderberry proteins by one-dimensional (1D) and 2D electrophoresis/immunoblotting. Inhibition studies with defined allergens and elderberry-specific antibodies were used to evaluate cross-reactivity. The main elderberry allergen was purified by gel filtration and reversed-phase HPLC, and subjected to mass spectrometry. The in-gel-digested allergen was analysed by the MS/MS sequence analysis and peptide mapping. The N-terminal sequence of the predominant allergen was analysed. 0.6% of 3668 randomly tested patients showed positive skin prick test and/or RAST to elderberry. IgE in patients' sera detected a predominant allergen of 33.2 kDa in extracts from elderberry pollen, flowers and berries, with an isoelectric point at pH 7.0. Pre-incubation of sera with extracts from birch, mugwort or grass pollen rendered insignificant or no inhibition of IgE binding to blotted elderberry proteins. Specific mouse antisera reacted exclusively with proteins from elderberry. N-terminal sequence analysis, as well as MS/MS spectrometry of the purified elderberry allergen, indicated homology with ribosomal inactivating proteins (RIPs). We present evidence that the elderberry plant S. nigra harbours allergenic potency. Independent methodologies argue for a significant homology of the predominant 33.2 kDa elderberry allergen with homology to RIPs. We

  17. Study of HMG-CoA Reductase Inhibition Activity of the Hydrolyzed Product of Snakehead Fish (Channa striata) Skin Collagen with 50 kDa Collagenase from Bacillus licheniformis F11.4

    PubMed Central

    Virginia, Agnes; Rachmawati, Heni; Riani, Catur; Retnoningrum, Debbie S.

    2016-01-01

    Bioactive peptides produced from enzymatic hydrolysis fibrous protein have been proven to have several biological activities. Previous study showed that the hydrolysis product of snakehead fish skin collagen with 26 kDa collagenase from Bacillus licheniformis F11.4 showed HMG-CoA (HMGR) inhibition activity. The aim of this research was to determine the ability of the hydrolysis product produced from snakehead fish skin collagen hydrolysed by 50 kDa collagenase from B. licheniformis F11.4 in inhibiting HMGR activity. Snakehead fish skin collagen was extracted using an acid method and collagenase was produced from B. licheniformis F11.4 using half-strength Luria Bertani (LB) medium containing 5% collagen. Crude collagenase was concentrated and fractionated using the DEAE Sephadex A-25 column eluted with increasing gradient concentrations of NaCl. Collagen, collagenase, and fractions were analyzed using SDS-PAGE and collagenolytic activity was analyzed by the zymography method. Collagenase with 50 kDa molecular weight presented in fraction one was used to hydrolyze the collagen. The reaction was done in 18 hours at 50°C. The hydrolysis product using 3.51 μg collagen and 9 ng collagenase showed 25.8% inhibition activity against pravastatin. This work shows for the first time that the hydrolysis product of snakehead fish skin collagen and 50 kDa collagenase from B. licheniformis F11.4 has potential as an anticholesterol agent. PMID:27110500

  18. Study of HMG-CoA Reductase Inhibition Activity of the Hydrolyzed Product of Snakehead Fish (Channa striata) Skin Collagen with 50 kDa Collagenase from Bacillus licheniformis F11.4.

    PubMed

    Virginia, Agnes; Rachmawati, Heni; Riani, Catur; Retnoningrum, Debbie S

    2016-01-01

    Bioactive peptides produced from enzymatic hydrolysis fibrous protein have been proven to have several biological activities. Previous study showed that the hydrolysis product of snakehead fish skin collagen with 26 kDa collagenase from Bacillus licheniformis F11.4 showed HMG-CoA (HMGR) inhibition activity. The aim of this research was to determine the ability of the hydrolysis product produced from snakehead fish skin collagen hydrolysed by 50 kDa collagenase from B. licheniformis F11.4 in inhibiting HMGR activity. Snakehead fish skin collagen was extracted using an acid method and collagenase was produced from B. licheniformis F11.4 using half-strength Luria Bertani (LB) medium containing 5% collagen. Crude collagenase was concentrated and fractionated using the DEAE Sephadex A-25 column eluted with increasing gradient concentrations of NaCl. Collagen, collagenase, and fractions were analyzed using SDS-PAGE and collagenolytic activity was analyzed by the zymography method. Collagenase with 50 kDa molecular weight presented in fraction one was used to hydrolyze the collagen. The reaction was done in 18 hours at 50°C. The hydrolysis product using 3.51 μg collagen and 9 ng collagenase showed 25.8% inhibition activity against pravastatin. This work shows for the first time that the hydrolysis product of snakehead fish skin collagen and 50 kDa collagenase from B. licheniformis F11.4 has potential as an anticholesterol agent.

  19. Structure of the putative 32 kDa myrosinase-binding protein from Arabidopsis (At3g16450.1) determined by SAIL-NMR.

    PubMed

    Takeda, Mitsuhiro; Sugimori, Nozomi; Torizawa, Takuya; Terauchi, Tsutomu; Ono, Akira M; Yagi, Hirokazu; Yamaguchi, Yoshiki; Kato, Koichi; Ikeya, Teppei; Jee, Jungoo; Güntert, Peter; Aceti, David J; Markley, John L; Kainosho, Masatsune

    2008-12-01

    The product of gene At3g16450.1 from Arabidopsis thaliana is a 32 kDa, 299-residue protein classified as resembling a myrosinase-binding protein (MyroBP). MyroBPs are found in plants as part of a complex with the glucosinolate-degrading enzyme myrosinase, and are suspected to play a role in myrosinase-dependent defense against pathogens. Many MyroBPs and MyroBP-related proteins are composed of repeated homologous sequences with unknown structure. We report here the three-dimensional structure of the At3g16450.1 protein from Arabidopsis, which consists of two tandem repeats. Because the size of the protein is larger than that amenable to high-throughput analysis by uniform (13)C/(15)N labeling methods, we used stereo-array isotope labeling (SAIL) technology to prepare an optimally (2)H/(13)C/(15)N-labeled sample. NMR data sets collected using the SAIL protein enabled us to assign (1)H, (13)C and (15)N chemical shifts to 95.5% of all atoms, even at a low concentration (0.2 mm) of protein product. We collected additional NOESY data and determined the three-dimensional structure using the cyana software package. The structure, the first for a MyroBP family member, revealed that the At3g16450.1 protein consists of two independent but similar lectin-fold domains, each composed of three beta-sheets.

  20. Isolation and characterization of cDNA clones for carrot extensin and a proline-rich 33-kDa protein

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, J.; Varner, J.E.

    1985-07-01

    Extensins are hydroxyproline-rich glycoproteins associated with most dicotyledonous plant cell walls. To isolate cDNA clones encoding extensin, the authors started by isolating poly(A) RNA from carrot root tissue, and then translating the RNA in vitro, in the presence of tritiated leucine or proline. A 33-kDa peptide was identified in the translation products as a putative extensin precursor. From a cDNA library constructed with poly(A) RNA from wounded carrots, one cDNA clone (pDC5) was identified that specifically hybridized to poly(A) RNA encoding this 33-kDa peptide. They isolated three cDNA clones (pDC11, pDC12, and pDC16) from another cDNA library using pCD5 asmore » a probe. DNA sequence data, RNA hybridization analysis, and hybrid released in vitro translation indicate that the cDNA clones pDC11 encodes extensin and that cDNA clones pDC12 and pDC16 encode the 33-kDa peptide, which as yet has an unknown identity and function. The assumption that the 33-kDa peptide was an extensin precursor was invalid. RNA hybridization analysis showed that RNA encoded by both clone types is accumulated upon wounding.« less

  1. Analysis of protein profiles in diabetic rat blood plasma that induced by alloxan

    NASA Astrophysics Data System (ADS)

    Hidayati, Dewi; Abdulgani, Nurlita; Setiyawan, Hengki; Trisnawati, Indah; Ashuri, Nova Maulidina; Sa'adah, Noor Nailis

    2017-06-01

    Proteomics is the study to identify the proteins involved in physiological metabolic pathway. The protein profiles of blood plasma from alloxan-induced diabetic rats has investigated using Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE). Data were analyzed descriptively based on variations of the type and intensity of the protein. There were identified the similarity of protein variant between diabetic and control rats included ankyrin (200kDa), IgG (150kDa), nephrin (136 kDa), IDE (112 kDA), albumin (66 kDa), prealbumin (55 kDA), CICP (43 kDa), ApoA-V (39 kDa), GAPDH (35 kDa), C-RP (27,1 kDa), leptin (16 kDa) and apelin (13 kDa). However, the apelin profile at diabetic rats shows the higher intensity than control.

  2. [Blood plasma protein adsorption capacity of perfluorocarbon emulsion stabilized by proxanol 268 (in vitro and in vivo studies)].

    PubMed

    Sklifas, A N; Zhalimov, V K; Temnov, A A; Kukushkin, N I

    2012-01-01

    The adsorption abilities of the perfluorocarbon emulsion stabilized by Proxanol 268 were investigated in vitro and in vivo. In vitro, the saturation point for the blood plasma proteins was nearly reached after five minutes of incubation of the emulsion with human/rabbit blood plasma and was stable for all incubation periods studied. The decrease in volume ratio (emulsion/plasma) was accompanied by the increase in the adsorptive capacity of the emulsion with maximal values at 1/10 (3.2 and 1.5 mg of proteins per 1 ml of the emulsion, for human and rabbit blood plasma, respectively) that was unchanged at lower ratios. In vivo, in rabbits, intravenously injected with the emulsion, the proteins with molecular masses of 12, 25, 32, 44, 55, 70, and 200 kDa were adsorbed by the emulsion (as in vitro) if it was used 6 hours or less before testing. More delayed testing (6 h) revealed elimination of proteins with molecular masses of 25 and 44 kDa and an additional pool of adsorpted new ones of 27, 50, and 150 kDa. Specific adsorptive capacity of the emulsion enhanced gradually after emulsion injection and reached its maximum (3.5-5 mg of proteins per 1 ml of the emulsion) after 24 hours.

  3. A sequential mechanism for clathrin cage disassembly by 70-kDa heat-shock cognate protein (Hsc70) and auxilin

    PubMed Central

    Rothnie, Alice; Clarke, Anthony R.; Kuzmic, Petr; Cameron, Angus; Smith, Corinne J.

    2011-01-01

    An essential stage in endocytic coated vesicle recycling is the dissociation of clathrin from the vesicle coat by the molecular chaperone, 70-kDa heat-shock cognate protein (Hsc70), and the J-domain-containing protein, auxilin, in an ATP-dependent process. We present a detailed mechanistic analysis of clathrin disassembly catalyzed by Hsc70 and auxilin, using loss of perpendicular light scattering to monitor the process. We report that a single auxilin per clathrin triskelion is required for maximal rate of disassembly, that ATP is hydrolyzed at the same rate that disassembly occurs, and that three ATP molecules are hydrolyzed per clathrin triskelion released. Stopped-flow measurements revealed a lag phase in which the scattering intensity increased owing to association of Hsc70 with clathrin cages followed by serial rounds of ATP hydrolysis prior to triskelion removal. Global fit of stopped-flow data to several physically plausible mechanisms showed the best fit to a model in which sequential hydrolysis of three separate ATP molecules is required for the eventual release of a triskelion from the clathrin–auxilin cage. PMID:21482805

  4. Draft Genome Sequences of Two Bacillus thuringiensis Strains and Characterization of a Putative 41.9-kDa Insecticidal Toxin

    PubMed Central

    Palma, Leopoldo; Muñoz, Delia; Berry, Colin; Murillo, Jesús; Caballero, Primitivo

    2014-01-01

    In this work, we report the genome sequencing of two Bacillus thuringiensis strains using Illumina next-generation sequencing technology (NGS). Strain Hu4-2, toxic to many lepidopteran pest species and to some mosquitoes, encoded genes for two insecticidal crystal (Cry) proteins, cry1Ia and cry9Ea, and a vegetative insecticidal protein (Vip) gene, vip3Ca2. Strain Leapi01 contained genes coding for seven Cry proteins (cry1Aa, cry1Ca, cry1Da, cry2Ab, cry9Ea and two cry1Ia gene variants) and a vip3 gene (vip3Aa10). A putative novel insecticidal protein gene 1143 bp long was found in both strains, whose sequences exhibited 100% nucleotide identity. The predicted protein showed 57 and 100% pairwise identity to protein sequence 72 from a patented Bt strain (US8318900) and to a putative 41.9-kDa insecticidal toxin from Bacillus cereus, respectively. The 41.9-kDa protein, containing a C-terminal 6× HisTag fusion, was expressed in Escherichia coli and tested for the first time against four lepidopteran species (Mamestra brassicae, Ostrinia nubilalis, Spodoptera frugiperda and S. littoralis) and the green-peach aphid Myzus persicae at doses as high as 4.8 µg/cm2 and 1.5 mg/mL, respectively. At these protein concentrations, the recombinant 41.9-kDa protein caused no mortality or symptoms of impaired growth against any of the insects tested, suggesting that these species are outside the protein’s target range or that the protein may not, in fact, be toxic. While the use of the polymerase chain reaction has allowed a significant increase in the number of Bt insecticidal genes characterized to date, novel NGS technologies promise a much faster, cheaper and efficient screening of Bt pesticidal proteins. PMID:24784323

  5. Domain organization of p130, PLC-related catalytically inactive protein, and structural basis for the lack of enzyme activity.

    PubMed

    Kanematsu, T; Yoshimura, K; Hidaka, K; Takeuchi, H; Katan, M; Hirata, M

    2000-05-01

    The 130-kDa protein (p130) was isolated as a novel inositol 1,4, 5-trisphosphate [Ins(1,4,5)P3]-binding protein similar to phospholipase C-delta1 (PLC-delta1), but lacking catalytic activity [Kanematsu, T., Takeya, H., Watanabe, Y., Ozaki, S., Yoshida, M., Koga, T., Iwanaga, S. & Hirata, M. (1992) J. Biol. Chem. 267, 6518-6525; Kanematsu, T., Misumi, Y., Watanabe, Y., Ozaki, S., Koga, T., Iwanaga, S., Ikehara, Y. & Hirata, M. (1996) Biochem. J. 313, 319-325]. To test experimentally the domain organization of p130 and structural basis for lack of PLC activity, we subjected p130 to limited proteolysis and also constructed a number of chimeras with PLC-delta1. Trypsin treatment of p130 produced four major polypeptides with molecular masses of 86 kDa, 55 kDa, 33 kDa and 25 kDa. Two polypeptides of 86 kDa and 55 kDa started at Lys93 and were calculated to end at Arg851 and Arg568, respectively. Using the same approach, it has been found that the polypeptides of 33 kDa and 25 kDa are likely to correspond to regions between Val569 and Arg851 and Lys869 and Leu1096, respectively. All the proteolytic sites were in interconnecting regions between the predicted domains, therefore supporting domain organization based on sequence similarity to PLC-delta1 and demonstrating that all domains of p130, including the unique region at the C-terminus, are stable, tightly folded structures. p130 truncated at either or both the N-terminus (94 amino acids) and C-terminus (851-1096 amino acids) expressed in COS-1 cells showed no catalytic activity, indicating that p130 has intrinsically no PLC activity. A number of chimeric molecules between p130 and PLC-delta1 were constructed and assayed for PLC activity. It was shown that structural differences in interdomain interactions exist between the two proteins, as only some domains of p130 could replace the corresponding structures in PLC-delta1 to form a functional enzyme. These results suggest that p130 and the related proteins could

  6. Structure of the Putative 32 kDa Myrosinase Binding Protein from Arabidopsis (At3g16450.1) Determined by SAIL-NMR

    PubMed Central

    Takeda, Mitsuhiro; Sugimori, Nozomi; Torizawa, Takuya; Terauchi, Tsutomu; Ono, Akira Mei; Yagi, Hirokazu; Yamaguchi, Yoshiki; Kato, Koichi; Ikeya, Teppei; Jee, JunGoo; Güntert, Peter; Aceti, David J.; Markley, John L.; Kainosho, Masatsune

    2009-01-01

    The product of gene At3g16450.1 from Arabidopsis thaliana is a 32 kDa, 299-residue protein classified as resembling a myrosinase-binding protein (MyroBP). MyroBPs are found in plants as part of a complex with the glucosinolate-degrading enzyme, myrosinase, and are suspected to play a role in myrosinase-dependent defense against pathogens. Many MyroBPs and MyroBP-related proteins are composed of repeated homologous sequences with unknown structure. We report here the three-dimensional structure of the At3g16450.1 protein from Arabidopsis, which consists of two tandem repeats. Because the size of the protein is larger than that amenable to high-throughput analysis by uniformly 13C/15N labeling methods, we used our stereo-array isotope labeling (SAIL) technology to prepare an optimally 2H/13C/15N-labeled sample. NMR data sets collected with the SAIL-protein enabled us to assign 1H, 13C and 15N chemical shifts to 95.5% of all atoms, even at the low concentration (0.2 mM) of the protein product. We collected additional NOESY data and solved the three-dimensional structure with the CYANA software package. The structure, the first for a MyroBP family member, revealed that the At3g16450.1 protein consists of two independent, but similar, lectin-fold domains composed of three β-sheets. PMID:19021763

  7. Insulin stimulates the tyrosine phosphorylation of a 61-kilodalton protein in rat adipocytes.

    PubMed

    Mooney, R A; Bordwell, K L

    1992-03-01

    Insulin stimulated the tyrosine phosphorylation of a 61-kilodalton (kDa) protein in rat adipocytes prelabeled for 2 h with [32P]orthophosphate. Tyrosine phosphorylation of this 61-kDa protein displayed very similar insulin concentration dependency to receptor autophosphorylation and tyrosine phosphorylation of a high molecular mass receptor substrate of 160 kDa. Phosphorylation of the 61-kDa protein was very rapid with maximum labeling attained at 30 sec, paralleling that of the other two proteins. Phosphoamino acid analysis revealed that each of the insulin-responsive phosphoproteins contained phosphoserine as well as phosphotyrosine, though the ratio of two phosphoamino acids recovered from each protein differed. The 61-kDa protein yielded relatively equal proportions of phosphoserine and phosphotyrosine. In contrast, the insulin receptor yielded relatively more label on phosphotyrosine than phosphoserine, whereas label incorporated into the 160-kDa protein was recovered primarily on phosphoserine. Cleveland peptide maps using either Staphylococcus aureus V8 proteinase or chymotrypsin revealed no similarities between the 61-kDa protein and the other tyrosine phosphorylated proteins. With subcellular fractionation, the 160-kDa protein was found in equal proportions in the high speed pellet (100,000 g) and supernatant. The 61-kDa protein had a similar distribution to that of the 160-kDa protein but was also detected in the low speed pellet (10,000 g). The insulin receptor was localized to the low speed pellet. In summary, rat adipocytes contain an insulin-dependent phosphotyrosyl protein of 61 kDa which is distinct from the more prominent high molecular mass receptor substrate. This 61-kDa protein has characteristics consistent with it being a substrate for the insulin receptor tyrosine kinase.

  8. Possibility of the transformation of eEF-2 (100 kDa) to eEF-2 (65 kDa) in the peptide elongation process in vitro.

    PubMed

    Gajko, A; Sredzińska, K; Galasiński, W; Gindzieński, A

    1999-02-16

    Two active eEF-2 polypeptides of approximately 100 and 65 kDa were copurified from rat liver cells and separated. The fate of eEF-2 (100 kDa) during its binding to ribosomes and in the translocation step of the peptide elongation process was investigated. It was shown that eEF-2 (100 kDa) did not change its form during the process of binding to the ribosomes. In the postribosomal supernatant, obtained from the postincubation mixture of the elongation process, only eEF-2 (65 kDa) was found. These results suggest that the form of eEF-2 (100 kDa), when bound to the ribosome during the elongation process, is transformed to eEF-2 (65 kDa). Copyright 1999 Academic Press.

  9. Bovine oocytes with the potential to reprogram somatic cell nuclei have a unique 23-kDa protein, phosphorylated transcriptionally controlled tumor protein (TCTP).

    PubMed

    Tani, Tetsuya; Shimada, Hiroaki; Kato, Yoko; Tsunoda, Yukio

    2007-01-01

    Despite the long-held assumption that reprogramming factors are present in mammalian oocytes at the second metaphase stage, the molecular nature of these factors is not known. Here, we demonstrated that oocytes with the potential to reprogram somatic cell nuclei have a unique 23-kDa protein, phosphorylated transcriptionally controlled tumor protein (TCTP). Injection of TCTP double-stranded RNA into germinal vesicle oocytes decreased the potential of nuclear-transferred (NT) oocytes, but not in vitro fertilized oocytes, to develop into blastocysts. Phosphorylated TCTP is considered to facilitate the first step of somatic cell reprogramming. After transfer of blastocysts that developed from NT oocytes fused with cumulus cells in which phosphorylated TCTP peptide was previously incorporated, the recipient pregnancy rate (47%) increased and the abortion rate (13%) decreased. Moreover, all seven cloned calves survived for at least 1 month after parturition, and had no morphologic abnormalities. The present study demonstrated that pretreatment of donor cells with phosphorylated TCTP peptide has a beneficial effect on the potential of bovine somatic cell nuclei to develop into normal cloned calves. Before widespread application of TCTP for bovine cloning, however, a large-scale embryo transfer study using different donor cell lines of various origins is necessary.

  10. Identification of a 170-kDa protein associated with the vacuolar Na+/H+ antiport of Beta vulgaris.

    PubMed Central

    Barkla, B J; Blumwald, E

    1991-01-01

    The effect of the addition of amiloride to the growth medium was tested on the Na+/H+ antiport activity of tonoplast vesicles isolated from sugar beet (beta vulgaris L.) cell suspensions. Cells grown in the presence of NaCl and amiloride displayed an increased antiport activity. Analysis of the kinetic data showed that while the affinity of the antiport for Na+ ions did not change, the maximal velocity of the Na+/H+ exchange increased markedly. These results suggest the addition of more antiport molecules to the tonoplast and/or an increase in the turnover rate of the Na+/H+ exchange. The increase in activity of the antiport by the presence of amiloride was correlated with the enhanced synthesis of a tonoplast 170-kDa polypeptide. The increased synthesis of this polypeptide was detected not only upon exposure of the cells to amiloride but also when the cells were exposed to high NaCl concentrations. Polyclonal antibodies against the 170-kDa polypeptide almost completely inhibited the antiport activity. These results suggest the association of the 170-kDa polypeptide with the vacuolar Na+/H+ antiport. Images PMID:1662387

  11. Identification of a 170-kDa protein associated with the vacuolar Na+/H+ antiport of Beta vulgaris.

    PubMed

    Barkla, B J; Blumwald, E

    1991-12-15

    The effect of the addition of amiloride to the growth medium was tested on the Na+/H+ antiport activity of tonoplast vesicles isolated from sugar beet (beta vulgaris L.) cell suspensions. Cells grown in the presence of NaCl and amiloride displayed an increased antiport activity. Analysis of the kinetic data showed that while the affinity of the antiport for Na+ ions did not change, the maximal velocity of the Na+/H+ exchange increased markedly. These results suggest the addition of more antiport molecules to the tonoplast and/or an increase in the turnover rate of the Na+/H+ exchange. The increase in activity of the antiport by the presence of amiloride was correlated with the enhanced synthesis of a tonoplast 170-kDa polypeptide. The increased synthesis of this polypeptide was detected not only upon exposure of the cells to amiloride but also when the cells were exposed to high NaCl concentrations. Polyclonal antibodies against the 170-kDa polypeptide almost completely inhibited the antiport activity. These results suggest the association of the 170-kDa polypeptide with the vacuolar Na+/H+ antiport.

  12. Characterization of a major 31-kilodalton peptidoglycan-bound protein of Legionella pneumophila

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Butler, C.A.; Hoffman, P.S.

    1990-05-01

    A 31-kilodalton (kDa) protein was solubilized from the peptidoglycan (PG) fraction of Legionella pneumophila after treatment with either N-acetylmuramidase from the fungus Chalaropsis sp. or with mutanolysin from Streptomyces globisporus. The protein exhibited a ladderlike banding pattern by autoradiography when radiolabeled ((35S)cysteine or (35S)methionine) PG material was extensively treated with hen lysozyme. The banding patterns ranging between 31 and 45 kDa and between 55 and 60 kDa resolved as a single 31-kDa protein when the material was subsequently treated with N-acetylmuramidase. Analysis of the purified 31-kDa protein for diaminopimelic acid by gas chromatography revealed 1 mol of diaminopimelic acid permore » mol of protein. When outer membrane PG material containing the major outer membrane porin protein was treated with N-acetylmuramidase or mutanolysin, both the 28.5-kDa major outer membrane protein and the 31-kDa protein were solubilized from the PG material under reducing conditions. In the absence of 2-mercaptoethanol, a high-molecular-mass complex (100 kDa) was resolved. The results of this study indicate that a 31-kDa PG-bound protein is a major component of the cell wall of L. pneumophila whose function may be to anchor the major outer membrane protein to PG. Finally, a survey of other Legionella species and other serogroups of L. pneumophila suggested that PG-bound proteins may be a common feature of this genus.« less

  13. Antimicrobial activity of a 48-kDa protease (AMP48) from Artocarpus heterophyllus latex.

    PubMed

    Siritapetawee, J; Thammasirirak, S; Samosornsuk, W

    2012-01-01

    Artocarpus heterophyllus (jackfruit) is a latex producing plant. Plant latex is produced from secretory cells and contains many intergradients. It also has been used in folk medicine. This study aimed to purify and characterize the biological activities of a protease from jackfruit latex. A protease was isolated and purified from crude latex of a jackfruit tree by acid precipitation and ion exchange chromatography. The proteolytic activities of protein were tested using gelatin- and casein-zymography. The molecular weight and isoelectric point (pl) of protein were analysed by SDS/12.5% PAGE and 2D-PAGE, respectively. Antimicrobial activity of protein was analysed by broth microdilution method. In addition, the antibacterial activity of protein against Pseudomonas aeruginosa ATCC 27853 was observed and measured using atomic force microscopy (AFM) technique. The purified protein contained protease activity by digesting gelatin- and casein-substrates. The protease was designated as antimicrobial protease-48 kDa or AMP48 due to its molecular mass on SDS-PAGE was approximately 48 kDa. The isoelectric point (pl) of AMP48 was approximately 4.2. In addition, AMP48 contained antimicrobial activities by it could inhibit the growths of Pseudomonas aeruginosa ATCC 27853 and clinical isolated Candida albicans at minimum inhibitory concentration (MIC) 2.2 mg/ml and Minimum microbicidal concentration (MMC) 8.8 mg/ml. AFM image also supported the antimicrobial activities of AMP48 by the treated bacterial morphology and size were altered from normal.

  14. Molecular cloning and sequence analysis of the gene coding for the 57kDa soluble antigen of the salmonid fish pathogen Renibacterium salmoninarum

    USGS Publications Warehouse

    Chien, Maw-Sheng; Gilbert , Teresa L.; Huang, Chienjin; Landolt, Marsha L.; O'Hara, Patrick J.; Winton, James R.

    1992-01-01

    The complete sequence coding for the 57-kDa major soluble antigen of the salmonid fish pathogen, Renibacterium salmoninarum, was determined. The gene contained an opening reading frame of 1671 nucleotides coding for a protein of 557 amino acids with a calculated Mr value of 57190. The first 26 amino acids constituted a signal peptide. The deduced sequence for amino acid residues 27–61 was in agreement with the 35 N-terminal amino acid residues determined by microsequencing, suggesting the protein in synthesized as a 557-amino acid precursor and processed to produce a mature protein of Mr 54505. Two regions of the protein contained imperfect direct repeats. The first region contained two copies of an 81-residue repeat, the second contained five copies of an unrelated 25-residue repeat. Also, a perfect inverted repeat (including three in-frame UAA stop codons) was observed at the carboxyl-terminus of the gene.

  15. The Induction of Recombinant Protein Bodies in Different Subcellular Compartments Reveals a Cryptic Plastid-Targeting Signal in the 27-kDa γ-Zein Sequence

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hofbauer, Anna; Peters, Jenny; Arcalis, Elsa

    2014-12-11

    Naturally occurring storage proteins such as zeins are used as fusion partners for recombinant proteins because they induce the formation of ectopic storage organelles known as protein bodies (PBs) where the proteins are stabilized by intermolecular interactions and the formation of disulfide bonds. Endogenous PBs are derived from the endoplasmic reticulum (ER). Here, we have used different targeting sequences to determine whether ectopic PBs composed of the N-terminal portion of mature 27 kDa γ-zein added to a fluorescent protein could be induced to form elsewhere in the cell. The addition of a transit peptide for targeting to plastids causes PBmore » formation in the stroma, whereas in the absence of any added targeting sequence PBs were typically associated with the plastid envelope, revealing the presence of a cryptic plastid-targeting signal within the γ-zein cysteine-rich domain. The subcellular localization of the PBs influences their morphology and the solubility of the stored recombinant fusion protein. Our results indicate that the biogenesis and budding of PBs does not require ER-specific factors and therefore, confirm that γ-zein is a versatile fusion partner for recombinant proteins offering unique opportunities for the accumulation and bioencapsulation of recombinant proteins in different subcellular compartments.« less

  16. Identification of pheromone-carrying protein in the preorbital gland post in the endangered Indian male Blackbuck Antelope cervicapra L.

    PubMed

    Rajagopal, T; Rajkumar, R; Ponmanickam, P; Achiraman, S; Padmanabhan, P; Archunan, G

    2015-12-01

    In mammals, a low molecular mass protein (17-20 KDa) reported from the pheromone sources such as urine, saliva, glandular secretion, etc., as ligand-carrier (pheromone carrier) has been associated with chemo-communication. Since the preorbital gland post is one of the major pheromone sources in Indian Blackbuck, an endangered species, we assumed that it possibly contains low molecular mass protein for chemical communication. Hence, we investigated the preorbital gland post in territorial and non-territorial male blackbucks for such low molecular mass proteins adopting SDS-PAGE and LC-MS/MS analysis. The total content of protein was higher in the post of territorial males than non-territorial males of adult and sub-adult. In fact, the protein profiles such as 17, 21, 25, 42 and 61 kDa were noted in the gland secretion of territorial and non-territorial males. The intensity of the 17 kDa protein band was higher in territorial males than non-territorial males. In-gel trypsin digestion of the 17 kDa band was processed and subjected to LC-MS/MS and SEQUEST analyses. The results of LC-MS/MS and SEQUEST search showed the presence of α(2u)-globulin in the 17 kDa band. In addition, the identified α(2u)-globulin sequence possessed GDW residues, which are the characteristic signature for lipocalin family. Since the α(2u)-globulin has been reported from the pheromone-carrying proteins in some mammals, this protein may carry the volatiles (pheromone compounds) in male Blackbucks preorbital gland to evoke the scent marking for maintaining territoriality (home range) and attraction towards female, through the secretion of glandular protein.

  17. Host transcription factor Speckled 110 kDa (Sp110), a nuclear body protein, is hijacked by hepatitis B virus protein X for viral persistence.

    PubMed

    Sengupta, Isha; Das, Dipanwita; Singh, Shivaram Prasad; Chakravarty, Runu; Das, Chandrima

    2017-12-15

    Promyelocytic leukemia nuclear bodies (PML-NB) are sub-nuclear organelles that are the hub of numerous proteins. DNA/RNA viruses often hijack the cellular factors resident in PML-NBs to promote their proliferation in host cells. Hepatitis B virus (HBV), belonging to Hepadnaviridae family, remains undetected in early infection as it does not induce the innate immune response and is known to be the cause of several hepatic diseases leading to cirrhosis and hepatocellular carcinoma. The association of PML-NB proteins and HBV is being addressed in a number of recent studies. Here, we report that the PML-NB protein Speckled 110 kDa (Sp110) is SUMO1-modified and undergoes a deSUMOylation-driven release from the PML-NB in the presence of HBV. Intriguingly, Sp110 knockdown significantly reduced viral DNA load in the culture supernatant by activation of the type I interferon-response pathway. Furthermore, we found that Sp110 differentially regulates several direct target genes of hepatitis B virus protein X (HBx), a viral co-factor. Subsequently, we identified Sp110 as a novel interactor of HBx and found this association to be essential for the exit of Sp110 from the PML-NB during HBV infection and HBx recruitment on the promoter of these genes. HBx, in turn, modulates the recruitment of its associated transcription cofactors p300/HDAC1 to these co-regulated genes, thereby altering the host gene expression program in favor of viral persistence. Thus, we report a mechanism by which HBV can evade host immune response by hijacking the PML-NB protein Sp110, and therefore, we propose it to be a novel target for antiviral therapy. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Protein denaturation improves enzymatic digestion efficiency for direct tissue analysis using mass spectrometry

    NASA Astrophysics Data System (ADS)

    Setou, M.; Hayasaka, T.; Shimma, S.; Sugiura, Y.; Matsumoto, M.

    2008-12-01

    Molecular identification using high-sensitivity tandem mass spectrometry is essential for protein analysis on the tissue surface. Here we report an improved digestion protocol for protein identification directly on the tissue surface using mass spectrometry. By denaturation process and the use of detergent-supplemented trypsin solution, we could successfully detect and identify many molecules such as tubulin, neurofilament, and synaptosomal-associated 25 kDa protein directly from a mouse cerebellum section.

  19. A metal-linked gapped zipper model is proposed for the 90 kDa heat shock protein-estrogen receptor interface.

    PubMed

    Schwartz, J A; Mizukami, H

    1991-06-01

    A novel arrangement is proposed for the association of the 90 kDa heat shock protein (hsp 90) dimer and the human estrogen receptor (hER) monomer. Secondary structure analyses of the hsp 90 molecule reveal the presence of a cysteine-containing, leucine-rich, heptad repeat, which we refer to as region C. Similar analyses on the hER, at its hormone binding domain (HBD), have indicated the presence of a central subdomain bordered by 2 alpha-helical flanking segments which also display the heptad substructure. Due to its predicted potential for conformational change (1) we refer to this central subdomain as the Helix Conversion Unit or HCU. It contains an HX5C peptide and shares significant homology with the metal-binding domain of a gag-encoded HIV-LAV protein (2). We predict that, by virtue of its presence in duplicate, region C may be capable of simultaneous leucine zipper-like pairing with the hER at its flanking helices, as well as the formation of a shared CCHC-box-type metal binding link with the same hER at the putative HCU which lies in between.

  20. Striated fibers in trichomonads: costa proteins represent a new class of proteins forming striated roots.

    PubMed

    Viscogliosi, E; Brugerolle, G

    1994-01-01

    The production of monoclonal antibodies and the use of biochemical techniques revealed that B-type costa proteins in trichomonads are composed of several major polypeptides with molecular weight detected between 100 and 135 kDa similar to those found in the A-type costae. Although differences were observed between the two types in their fine structure, we tested whether proteins composing the two costa types belong to the same protein family. A polyclonal antibody produced against the 118 kDa costa protein of Trichomonas vaginalis also recognized a 118 kDa costa protein in all other trichomonad genera studied so far whether they have A- or B-type costae. Moreover biochemical characteristics of costa proteins indicated that these proteins might represent a novel class of striated root-forming proteins in addition to centrin, giardin, and assemblin.

  1. The Effects of Threonine Phosphorylation on the Stability and Dynamics of the Central Molecular Switch Region of 18.5-kDa Myelin Basic Protein

    PubMed Central

    De Avila, Miguel; Polverini, Eugenia; Harauz, George

    2013-01-01

    The classic isoforms of myelin basic protein (MBP) are essential for the formation and maintenance of myelin in the central nervous system of higher vertebrates. The protein is involved in all facets of the development, compaction, and stabilization of the multilamellar myelin sheath, and also interacts with cytoskeletal and signaling proteins. The predominant 18.5-kDa isoform of MBP is an intrinsically-disordered protein that is a candidate auto-antigen in the human demyelinating disease multiple sclerosis. A highly-conserved central segment within classic MBP consists of a proline-rich region (murine 18.5-kDa sequence –T92-P93-R94-T95-P96-P97-P98-S99–) containing a putative SH3-ligand, adjacent to a region that forms an amphipathic α-helix (P82-I90) upon interaction with membranes, or under membrane-mimetic conditions. The T92 and T95 residues within the proline-rich region can be post-translationally modified through phosphorylation by mitogen-activated protein (MAP) kinases. Here, we have investigated the structure of the α-helical and proline-rich regions in dilute aqueous buffer, and have evaluated the effects of phosphorylation at T92 and T95 on the stability and dynamics of the α-helical region, by utilizing four 36-residue peptides (S72–S107) with differing phosphorylation status. Nuclear magnetic resonance spectroscopy reveals that both the α-helical as well as the proline-rich regions are disordered in aqueous buffer, whereas they are both structured in a lipid environment (cf., Ahmed et al., Biochemistry 51, 7475-9487, 2012). Thermodynamic analysis of trifluoroethanol-titration curves monitored by circular dichroism spectroscopy reveals that phosphorylation, especially at residue T92, impedes formation of the amphipathic α-helix. This conclusion is supported by molecular dynamics simulations, which further illustrate that phosphorylation reduces the folding reversibility of the α-helix upon temperature perturbation and affect the global

  2. The effects of threonine phosphorylation on the stability and dynamics of the central molecular switch region of 18.5-kDa myelin basic protein.

    PubMed

    Vassall, Kenrick A; Bessonov, Kyrylo; De Avila, Miguel; Polverini, Eugenia; Harauz, George

    2013-01-01

    The classic isoforms of myelin basic protein (MBP) are essential for the formation and maintenance of myelin in the central nervous system of higher vertebrates. The protein is involved in all facets of the development, compaction, and stabilization of the multilamellar myelin sheath, and also interacts with cytoskeletal and signaling proteins. The predominant 18.5-kDa isoform of MBP is an intrinsically-disordered protein that is a candidate auto-antigen in the human demyelinating disease multiple sclerosis. A highly-conserved central segment within classic MBP consists of a proline-rich region (murine 18.5-kDa sequence -T92-P93-R94-T95-P96-P97-P98-S99-) containing a putative SH3-ligand, adjacent to a region that forms an amphipathic α-helix (P82-I90) upon interaction with membranes, or under membrane-mimetic conditions. The T92 and T95 residues within the proline-rich region can be post-translationally modified through phosphorylation by mitogen-activated protein (MAP) kinases. Here, we have investigated the structure of the α-helical and proline-rich regions in dilute aqueous buffer, and have evaluated the effects of phosphorylation at T92 and T95 on the stability and dynamics of the α-helical region, by utilizing four 36-residue peptides (S72-S107) with differing phosphorylation status. Nuclear magnetic resonance spectroscopy reveals that both the α-helical as well as the proline-rich regions are disordered in aqueous buffer, whereas they are both structured in a lipid environment (cf., Ahmed et al., Biochemistry 51, 7475-9487, 2012). Thermodynamic analysis of trifluoroethanol-titration curves monitored by circular dichroism spectroscopy reveals that phosphorylation, especially at residue T92, impedes formation of the amphipathic α-helix. This conclusion is supported by molecular dynamics simulations, which further illustrate that phosphorylation reduces the folding reversibility of the α-helix upon temperature perturbation and affect the global structure

  3. Effect of gamma irradiation on the expressed proteins in the foodborne pathogen Staphylococcus aureus

    NASA Astrophysics Data System (ADS)

    Trudeau, Karine; Dang Vu, Khanh; Shareck, François; Lacroix, Monique

    2012-08-01

    A capillary electrophoresis method with UV detection was developed to analyze protein composition of the foodborne pathogen Staphylococcus aureus. Bacterial samples containing 109 CFU/ml, obtained after two cycles of incubations of 24 h, were gamma irradiated at different doses of 1.2, 3.5 and 2.9 kGy to respectively create damage cells, to kill cells and to provoke viable but non cultivable cells (VBNC). It was observed that an irradiation at a sensitive dose of 1.2 kGy caused a significantly increase in the protein with molecular weight (MW) of 17.7 kDa (from 0.61% to 1.2%). This treatment also caused decreases in the expressed proteins with the MWs of 16.3 kDa (from 6.2% to 5.3%) and of 23.4 kDa (from 4.0% to 2.30%). Irradiation at a VBCN dose of 2.9 kGy caused increases in expressed proteins with the MWs of 17.7 kDa (from 0.61% to 3.43%), 18.7 kDa (from 1.04% to 4.30%), 19.5 kDa (from 0.71% to 2.30%), 21.1 kDa (from 1.20% to 3.80%). Moreover, this treatment (2.9 kGy) also caused significantly decreases (P≤0.05) in the expressed proteins with the MW of 30.7 kDa (from 8.6% to 5.15%), 36.3 kDa (from 3.1% to 2.7%) and 40.5 kDa (from 11.3% to 8.5%). Finally, for the irradiation at a lethal dose of 3.5 kGy, it can be found that the expressed proteins with the MW of 17.7 kDa, 18.7 kDa and 19.5 kDa were increased less than that of expressed proteins at the VCNC dose (2.9 kGy) and these might be the very important proteins which are responsible for the survival of the S. aureus. Further, there were also the decreases in expressed proteins with the MW of 30.7 kDa, 36.3 kDa and 75.1 kDa at this dose of treatment (3.5 kGy) which can be expected that these proteins are seriously affected at high dose of γ-irradiation treatment.

  4. Can urinary excretion rate of malondialdehyde, uric acid and protein predict the severity and impending death in perinatal asphyxia?

    PubMed

    Banupriya, C; Ratnakar; Doureradjou, P; Mondal, N; Vishnu, Bhat; Koner, B C

    2008-08-01

    Perinatal asphyxia (PA) associated with multi-organ damage is a leading cause of neonatal mortality and morbidity. We evaluated if urinary malondialdehyde:creatinine (UMDA:Cr), uric acid:creatinine (UUA:Cr) and protein:creatinine (UP:Cr) vary with the severity of PA and if these parameters can predict the impending death in PA. Study included 20 asphyxiated and 20 healthy newborn males. Hypoxic-ischemic encephalopathy (HIE) staging, APGAR (activity, pulse, grimace, appearance and respiration) score and urinary protein, uric acid, creatinine and MDA were evaluated. UMDA:Cr, UUA:Cr and UP:Cr were significantly higher and correlated with APGAR and HIE in PA. By regression analysis also, urinary parameters were found to have significant association with HIE stage and APGAR in PA. Receiver operating characteristics (ROC) curve of UP:Cr, UUA:Cr and UMDA:Cr showed area under curve of 0.896 (p=0.003), 0.859 (p=0.008) and 0.849 (p=0.010) with cut-off value of 9.04 mg, 2.34 mg and 3.49 microg/mg of creatinine respectively that can optimally predict the impending death in PA. SDS-PAGE of unconcentrated urine detected both high (73 kDa and 68 kDa) and low molecular weight proteins (52 kDa, 47 kDa, 25 kDa and 20 kDa) in PA but not in controls. Urinary excretion rate of uric acid, MDA and proteins is higher and has potential to act as biochemical markers for severity evaluation and death prediction in PA.

  5. Agarose and Polyacrylamide Gel Electrophoresis Methods for Molecular Mass Analysis of 5–500 kDa Hyaluronan

    PubMed Central

    Bhilocha, Shardul; Amin, Ripal; Pandya, Monika; Yuan, Han; Tank, Mihir; LoBello, Jaclyn; Shytuhina, Anastasia; Wang, Wenlan; Wisniewski, Hans-Georg; de la Motte, Carol; Cowman, Mary K.

    2011-01-01

    Agarose and polyacrylamide gel electrophoresis systems for the molecular mass-dependent separation of hyaluronan (HA) in the size range of approximately 5–500 kDa have been investigated. For agarose-based systems, the suitability of different agarose types, agarose concentrations, and buffers systems were determined. Using chemoenzymatically synthesized HA standards of low polydispersity, the molecular mass range was determined for each gel composition, over which the relationship between HA mobility and logarithm of the molecular mass was linear. Excellent linear calibration was obtained for HA molecular mass as low as approximately 9 kDa in agarose gels. For higher resolution separation, and for extension to molecular masses as low as approximately 5 kDa, gradient polyacrylamide gels were superior. Densitometric scanning of stained gels allowed analysis of the range of molecular masses present in a sample, and calculation of weight-average and number-average values. The methods were validated for polydisperse HA samples with viscosity-average molecular masses of 112, 59, 37, and 22 kDa, at sample loads of 0.5 µg (for polyacrylamide) to 2.5 µg (for agarose). Use of the methods for electrophoretic mobility shift assays was demonstrated for binding of the HA-binding region of aggrecan (recombinant human aggrecan G1-IGD-G2 domains) to a 150 kDa HA standard. PMID:21684248

  6. Proline substitutions and threonine pseudophosphorylation of the SH3 ligand of 18.5-kDa myelin basic protein decrease its affinity for the Fyn-SH3 domain and alter process development and protein localization in oligodendrocytes.

    PubMed

    Smith, Graham S T; De Avila, Miguel; Paez, Pablo M; Spreuer, Vilma; Wills, Melanie K B; Jones, Nina; Boggs, Joan M; Harauz, George

    2012-01-01

    The developmentally regulated myelin basic proteins (MBPs), which arise from the golli (gene of oligodendrocyte lineage) complex, are highly positively charged, intrinsically disordered, multifunctional proteins having several alternatively spliced isoforms and posttranslational modifications, and they play key roles in myelin compaction. The classic 18.5-kDa MBP isoform has a proline-rich region comprising amino acids 92-99 (murine sequence -T(92)PRTPPPS(99)-) that contains a minimal SH3 ligand domain. We have previously shown that 18.5-kDa MBP binds to several SH3 domains, including that of Fyn, a member of the Src family of tyrosine kinases involved in a number of signaling pathways during CNS development. To determine the physiological role of this binding as well as the role of phosphorylation of Thr92 and Thr95, in the current study we have produced several MBP variants specifically targeting phosphorylation sites and key structural regions of MBP's SH3 ligand domain. Using isothermal titration calorimetry, we have demonstrated that, compared with the wild-type protein, these variants have lower affinity for the SH3 domain of Fyn. Moreover, overexpression of N-terminal-tagged GFP versions in immortalized oligodendroglial N19 and N20.1 cell cultures results in aberrant elongation of membrane processes and increased branching complexity and inhibits the ability of MBP to decrease Ca(2+) influx. Phosphorylation of Thr92 can also cause MBP to traffic to the nucleus, where it may participate in additional protein-protein interactions. Coexpression of MBP with a constitutively active form of Fyn kinase resulted in membrane process elaboration, a phenomenon that was abolished by point amino acid substitutions in MBP's SH3 ligand domain. These results suggest that MBP's SH3 ligand domain plays a key role in intracellular protein interactions in vivo and may be required for proper membrane elaboration of developing oligodendrocytes and, further, that phosphorylation

  7. Botulinum neurotoxin type A: Actions beyond SNAP-25?

    PubMed

    Matak, Ivica; Lacković, Zdravko

    2015-09-01

    Botulinum neurotoxin type A (BoNT/A), the most potent toxin known in nature which causes botulism, is a commonly used therapeutic protein. It prevents synaptic vesicle neuroexocytosis by proteolytic cleavage of synaptosomal-associated protein of 25 kDa (SNAP-25). It is widely believed that BoNT/A therapeutic or toxic actions are exclusively mediated by SNAP-25 cleavage. On the other hand, in vitro and in vivo findings suggest that several BoNT/A actions related to neuroexocytosis, cell cycle and apoptosis, neuritogenesis and gene expression are not necessarily mediated by this widely accepted mechanism of action. In present review we summarize the literature evidence which point to the existence of unknown BoNT/A molecular target(s) and modulation of unknown signaling pathways. The effects of BoNT/A apparently independent of SNAP-25 occur at similar doses/concentrations known to induce SNAP-25 cleavage and prevention of neurotransmitter release. Accordingly, these effects might be pharmacologically significant. Potentially the most interesting are observations of antimitotic and antitumor activity of BoNT/A. However, the exact mechanisms require further studies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. RNA Binding Protein RBM38 Regulates Expression of the 11-Kilodalton Protein of Parvovirus B19, Which Facilitates Viral DNA Replication.

    PubMed

    Ganaie, Safder S; Chen, Aaron Yun; Huang, Chun; Xu, Peng; Kleiboeker, Steve; Du, Aifang; Qiu, Jianming

    2018-04-15

    Human parvovirus B19 (B19V) expresses a single precursor mRNA (pre-mRNA), which undergoes alternative splicing and alternative polyadenylation to generate 12 viral mRNA transcripts that encode two structural proteins (VP1 and VP2) and three nonstructural proteins (NS1, 7.5-kDa protein, and 11-kDa protein). Splicing at the second 5' donor site (D2 site) of the B19V pre-mRNA is essential for the expression of VP2 and the 11-kDa protein. We previously identified that cis -acting intronic splicing enhancer 2 (ISE2) that lies immediately after the D2 site facilitates the recognition of the D2 donor for its efficient splicing. In this study, we report that ISE2 is critical for the expression of the 11-kDa viral nonstructural protein. We found that ISE2 harbors a consensus RNA binding motif protein 38 (RBM38) binding sequence, 5'-UGUGUG-3'. RBM38 is expressed during the middle stage of erythropoiesis. We first confirmed that RBM38 binds specifically with the ISE2 element in vitro The knockdown of RBM38 significantly decreases the level of spliced mRNA at D2 that encodes the 11-kDa protein but not that of the D2-spliced mRNA that encodes VP2. Importantly, we found that the 11-kDa protein enhances viral DNA replication and virion release. Accordingly, the knockdown of RBM38 decreases virus replication via downregulating 11-kDa protein expression. Taken together, these results suggest that the 11-kDa protein facilitates B19V DNA replication and that RBM38 is an essential host factor for B19V pre-mRNA splicing and for the expression of the 11-kDa protein. IMPORTANCE B19V is a human pathogen that can cause fifth disease, arthropathy, anemia in immunocompromised patients and sickle cell disease patients, myocarditis, and hydrops fetalis in pregnant women. Human erythroid progenitor cells (EPCs) are most susceptible to B19V infection and fully support viral DNA replication. The exclusive tropism of B19V for erythroid-lineage cells is dependent not only on the expression of viral

  9. The 'tubulin-like' S1 protein of Spirochaeta is a member of the hsp65 stress protein family

    NASA Technical Reports Server (NTRS)

    Munson, D.; Obar, R.; Tzertzinis, G.; Margulis, L.

    1993-01-01

    A 65-kDa protein (called S1) from Spirochaeta bajacaliforniensis was identified as 'tubulin-like' because it cross-reacted with at least four different antisera raised against tubulin and was isolated, with a co-polymerizing 45-kDa protein, by warm-cold cycling procedures used to purify tubulin from mammalian brain. Furthermore, at least three genera of non-cultivable symbiotic spirochetes (Pillotina, Diplocalyx, and Hollandina) that contain conspicuous 24-nm cytoplasmic tubules displayed a strong fluorescence in situ when treated with polyclonal antisera raised against tubulin. Here we summarize results that lead to the conclusion that this 65-kDa protein has no homology to tubulin. S1 is an hsp65 stress protein homologue. Hsp65 is a highly immunogenic family of hsp60 proteins which includes the 65-kDa antigens of Mycobacterium tuberculosis (an active component of Freund's complete adjuvant), Borrelia, Treponema, Chlamydia, Legionella, and Salmonella. The hsp60s, also known as chaperonins, include E. coli GroEL, mitochondrial and chloroplast chaperonins, the pea aphid 'symbionin' and many other proteins involved in protein folding and the stress response.

  10. Molecular differentiation and phylogenetic relationships of three Angiostrongylus species and Angiostrongylus cantonensis geographical isolates based on a 66-kDa protein gene of A. cantonensis (Nematoda: Angiostrongylidae).

    PubMed

    Eamsobhana, Praphathip; Lim, Phaik Eem; Zhang, Hongman; Gan, Xiaoxian; Yong, Hoi Sen

    2010-12-01

    The phylogenetic relationships and molecular differentiation of three species of angiostrongylid nematodes (Angiostrongylus cantonensis, Angiostrongylus costaricensis and Angiostrongylus malaysiensis) were studied using the AC primers for a 66-kDa protein gene of A. cantonensis. The AC primers successfully amplified the genomic DNA of these angiostrongylid nematodes. No amplification was detected for the DNA of Ascaris lumbricoides, Ascaris suum, Anisakis simplex, Gnathostoma spinigerum, Toxocara canis, and Trichinella spiralis. The maximum-parsimony (MP) consensus tree and the maximum-likelihood (ML) tree both showed that the Angiostrongylus taxa could be divided into two major clades - Clade 1 (A. costaricensis) and Clade 2 (A. cantonensis and A. malaysiensis) with a full support bootstrap value. A. costaricensis is the most distant taxon. A. cantonensis is a sister group to A. malaysiensis; these two taxa (species) are clearly separated. There is no clear distinction between the A. cantonensis samples from four different geographical localities (Thailand, China, Japan and Hawaii); only some of the samples are grouped ranging from no support or low support to moderate support of bootstrap values. The published nucleotide sequences of A. cantonensis adult-specific native 66kDa protein mRNA, clone L5-400 from Taiwan (U17585) appear to be very distant from the A. cantonensis samples from Thailand, China, Japan and Hawaii, with the uncorrected p-distance values ranging from 26.87% to 29.92%.

  11. Structural basis of UGUA recognition by the Nudix protein CFI(m)25 and implications for a regulatory role in mRNA 3' processing.

    PubMed

    Yang, Qin; Gilmartin, Gregory M; Doublié, Sylvie

    2010-06-01

    Human Cleavage Factor Im (CFI(m)) is an essential component of the pre-mRNA 3' processing complex that functions in the regulation of poly(A) site selection through the recognition of UGUA sequences upstream of the poly(A) site. Although the highly conserved 25 kDa subunit (CFI(m)25) of the CFI(m) complex possesses a characteristic alpha/beta/alpha Nudix fold, CFI(m)25 has no detectable hydrolase activity. Here we report the crystal structures of the human CFI(m)25 homodimer in complex with UGUAAA and UUGUAU RNA sequences. CFI(m)25 is the first Nudix protein to be reported to bind RNA in a sequence-specific manner. The UGUA sequence contributes to binding specificity through an intramolecular G:A Watson-Crick/sugar-edge base interaction, an unusual pairing previously found to be involved in the binding specificity of the SAM-III riboswitch. The structures, together with mutational data, suggest a novel mechanism for the simultaneous sequence-specific recognition of two UGUA elements within the pre-mRNA. Furthermore, the mutually exclusive binding of RNA and the signaling molecule Ap(4)A (diadenosine tetraphosphate) by CFI(m)25 suggests a potential role for small molecules in the regulation of mRNA 3' processing.

  12. Characterization of yam bean (Pachyrhizus erosus) proteins.

    PubMed

    Morales-Arellano, G Y; Chagolla-López, A; Paredes-López, O; Barba de la Rosa, A P

    2001-03-01

    Seed proteins from Mexican yam bean seeds (Pachyrhizus erosus L.) were sequentially extracted according to the Osborne classification. Albumins were the major fraction (52.1-31.0%), followed by globulins (30.7-27.5%). The minor protein fraction was prolamins (0.8%). Defatting with chloroform/methanol remarkably affected the distribution of protein solubility classes; albumins were the most affected fraction (4.3-17.5%). Electrophoretic patterns of albumins showed bands at 55, 40, 35, and 31 kDa. After reduction of the globulin fraction exhibited two triplets, one from 35 to 31 kDa and the second from 19 to 21 kDa, these could be compared to the acid and basic polypeptides of 11S-like proteins. Prolamins showed one band at 31 kDa, and glutelins after reduction showed three main bands at 52, 27, and 14 kDa. Trypsin inhibitors were assayed in saline extracts; the values found (1232-2608 IU/g of meal) were lower than those of other legumes. In general, yam bean seed proteins showed an excellent balance of all essential amino acids; albumins contain the highest amount of essential amino acids.

  13. CD25 and CD69 induction by α4β1 outside-in signalling requires TCR early signalling complex proteins

    PubMed Central

    Cimo, Ann-Marie; Ahmed, Zamal; McIntyre, Bradley W.; Lewis, Dorothy E.; Ladbury, John E.

    2013-01-01

    Distinct signalling pathways producing diverse cellular outcomes can utilize similar subsets of proteins. For example, proteins from the TCR (T-cell receptor) ESC (early signalling complex) are also involved in interferon-α receptor signalling. Defining the mechanism for how these proteins function within a given pathway is important in understanding the integration and communication of signalling networks with one another. We investigated the contributions of the TCR ESC proteins Lck (lymphocyte-specific kinase), ZAP-70 (ζ-chain-associated protein of 70 kDa), Vav1, SLP-76 [SH2 (Src homology 2)-domain-containing leukocyte protein of 76 kDa] and LAT (linker for activation of T-cells) to integrin outside-in signalling in human T-cells. Lck, ZAP-70, SLP-76, Vav1 and LAT were activated by α4β1 outside-in signalling, but in a manner different from TCR signalling. TCR stimulation recruits ESC proteins to activate the mitogen-activated protein kinase ERK (extracellular-signal-regulated kinase). α4β1 outside-in-mediated ERK activation did not require TCR ESC proteins. However, α4β1 outside-in signalling induced CD25 and co-stimulated CD69 and this was dependent on TCR ESC proteins. TCR and α4β1 outside-in signalling are integrated through the common use of TCR ESC proteins; however, these proteins display functionally distinct roles in these pathways. These novel insights into the cross-talk between integrin outside-in and TCR signalling pathways are highly relevant to the development of therapeutic strategies to overcome disease associated with T-cell deregulation. PMID:23758320

  14. Specific antibodies induced by nasally administered 40-kDa outer membrane protein of Porphyromonas gingivalis inhibits coaggregation activity of P. gingivalis.

    PubMed

    Namikoshi, Jun; Otake, Shigeo; Maeba, Satomi; Hayakawa, Mitsuo; Abiko, Yoshimitsu; Yamamoto, Masafumi

    2003-12-12

    In this study, we have assessed the efficacy of the 40-kDa outer membrane protein (40k-OMP) of Porphyromonas gingivalis as a nasal vaccine for the prevention of adult periodontitis. Mice nasally immunized with 40k-OMP and cholera toxin as mucosal adjuvant displayed significant levels of 40k-OMP-specific serum IgG1, IgG2b and IgA as well as mucosal IgA antibodies (Abs) in saliva and nasal secretions. Ab-forming cell (AFC) analysis confirmed the antibody titers by detecting high numbers of 40k-OMP-specific AFCs in spleen, salivary glands and nasal passages. Because 40k-OMP-specific IgG inhibited coaggregation of P. gingivalis vesicles and S. gordonii, it may be an important tool for the prevention of adult periodontitis.

  15. Surface Induced Dissociation Coupled with High Resolution Mass Spectrometry Unveils Heterogeneity of a 211 kDa Multicopper Oxidase Protein Complex

    NASA Astrophysics Data System (ADS)

    Zhou, Mowei; Yan, Jing; Romano, Christine A.; Tebo, Bradley M.; Wysocki, Vicki H.; Paša-Tolić, Ljiljana

    2018-01-01

    Manganese oxidation is an important biogeochemical process that is largely regulated by bacteria through enzymatic reactions. However, the detailed mechanism is poorly understood due to challenges in isolating and characterizing these unknown enzymes. A manganese oxidase, Mnx, from Bacillus sp. PL-12 has been successfully overexpressed in active form as a protein complex with a molecular mass of 211 kDa. We have recently used surface induced dissociation (SID) and ion mobility-mass spectrometry (IM-MS) to release and detect folded subcomplexes for determining subunit connectivity and quaternary structure. The data from the native mass spectrometry experiments led to a plausible structural model of this multicopper oxidase, which has been difficult to study by conventional structural biology methods. It was also revealed that each Mnx subunit binds a variable number of copper ions. Becasue of the heterogeneity of the protein and limited mass resolution, ambiguities in assigning some of the observed peaks remained as a barrier to fully understanding the role of metals and potential unknown ligands in Mnx. In this study, we performed SID in a modified Fourier transform-ion cyclotron resonance (FTICR) mass spectrometer. The high mass accuracy and resolution offered by FTICR unveiled unexpected artificial modifications on the protein that had been previously thought to be iron bound species based on lower resolution spectra. Additionally, isotopically resolved spectra of the released subcomplexes revealed the metal binding stoichiometry at different structural levels. This method holds great potential for in-depth characterization of metalloproteins and protein-ligand complexes. [Figure not available: see fulltext.

  16. Surface Induced Dissociation Coupled with High Resolution Mass Spectrometry Unveils Heterogeneity of a 211 kDa Multicopper Oxidase Protein Complex

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhou, Mowei; Yan, Jing; Romano, Christine A.

    Manganese oxidation is an important biogeochemical process that is largely regulated by bacteria through enzymatic reactions. However, the detailed mechanism is poorly understood due to challenges in isolating and characterizing these unknown enzymes. A manganese oxidase Mnx from Bacillus sp. PL-12 has been successfully overexpressed in active form, unexpectedly, as a protein complex with a molecular weight of 211 kDa with no homology to known proteins in the database. We have recently used surface induced dissociation (SID) and ion mobility – mass spectrometry (IM-MS) to release and detect folded subcomplexes for determining subunit connectivity and quaternary structure. The data frommore » the native mass spectrometry experiment led to a plausible model of this unknown multicopper oxidase which has been difficult to study by conventional structural biology methods. However, because each subunit of Mnx binds copper ions as cofactor at varying ratios, there were remaining ambiguities in assigning some of the observed peaks to metal-binding species because of the sample heterogeneity and limited mass resolution. In this study, we performed SID in a modified Fourier transform – ion cyclotron resonance (FT-ICR) mass spectrometer for obtaining the ultimate resolution on the released subcomplexes of Mnx. The high mass accuracy and resolution unveiled unexpected artificial modifications in the protein that have been previously thought to be iron bound species based on lower resolution data. Additionally, most released subcomplexes were isotopically resolved for defining metal binding stoichiometry at each structural level. This method holds great potential for in-depth characterization of metalloproteins and protein-ligand complexes.« less

  17. Characterization of auxin-binding proteins from zucchini plasma membrane

    NASA Technical Reports Server (NTRS)

    Hicks, G. R.; Rice, M. S.; Lomax, T. L.

    1993-01-01

    We have previously identified two auxin-binding polypeptides in plasma membrane (PM) preparations from zucchini (Cucurbita pepo L.) (Hicks et al. 1989, Proc. Natl. Acad. Sci. USA 86, 4948-4952). These polypeptides have molecular weights of 40 kDa and 42 kDa and label specifically with the photoaffinity auxin analog 5-N3-7-3H-IAA (azido-IAA). Azido-IAA permits both the covalent and radioactive tagging of auxin-binding proteins and has allowed us to characterize further the 40-kDa and 42-kDa polypeptides, including the nature of their attachment to the PM, their relationship to each other, and their potential function. The azido-IAA-labeled polypeptides remain in the pelleted membrane fraction following high-salt and detergent washes, which indicates a tight and possibly integral association with the PM. Two-dimensional electrophoresis of partially purified azido-IAA-labeled protein demonstrates that, in addition to the major isoforms of the 40-kDa and 42-kDa polypeptides, which possess isoelectric points (pIs) of 8.2 and 7.2, respectively, several less abundant isoforms that display unique pIs are apparent at both molecular masses. Tryptic and chymotryptic digestion of the auxin-binding proteins indicates that the 40-kDa and 42-kDa polypeptides are closely related or are modifications of the same polypeptide. Phase extraction with the nonionic detergent Triton X-114 results in partitioning of the azido-IAA-labeled polypeptides into the aqueous (hydrophilic) phase. This apparently paradoxical behavior is also exhibited by certain integral membrane proteins that aggregate to form channels. The results of gel filtration indicate that the auxin-binding proteins do indeed aggregate strongly and that the polypeptides associate to form a dimer or multimeric complex in vivo. These characteristics are consistent with the hypothesis that the 40-kDa and 42-kDa polypeptides are subunits of a multimeric integral membrane protein which has an auxin-binding site, and which may

  18. Characterization of auxin-binding proteins from zucchini plasma membrane.

    PubMed

    Hicks, G R; Rice, M S; Lomax, T L

    1993-01-01

    We have previously identified two auxin-binding polypeptides in plasma membrane (PM) preparations from zucchini (Cucurbita pepo L.) (Hicks et al. 1989, Proc. Natl. Acad. Sci. USA 86, 4948-4952). These polypeptides have molecular weights of 40 kDa and 42 kDa and label specifically with the photoaffinity auxin analog 5-N3-7-3H-IAA (azido-IAA). Azido-IAA permits both the covalent and radioactive tagging of auxin-binding proteins and has allowed us to characterize further the 40-kDa and 42-kDa polypeptides, including the nature of their attachment to the PM, their relationship to each other, and their potential function. The azido-IAA-labeled polypeptides remain in the pelleted membrane fraction following high-salt and detergent washes, which indicates a tight and possibly integral association with the PM. Two-dimensional electrophoresis of partially purified azido-IAA-labeled protein demonstrates that, in addition to the major isoforms of the 40-kDa and 42-kDa polypeptides, which possess isoelectric points (pIs) of 8.2 and 7.2, respectively, several less abundant isoforms that display unique pIs are apparent at both molecular masses. Tryptic and chymotryptic digestion of the auxin-binding proteins indicates that the 40-kDa and 42-kDa polypeptides are closely related or are modifications of the same polypeptide. Phase extraction with the nonionic detergent Triton X-114 results in partitioning of the azido-IAA-labeled polypeptides into the aqueous (hydrophilic) phase. This apparently paradoxical behavior is also exhibited by certain integral membrane proteins that aggregate to form channels. The results of gel filtration indicate that the auxin-binding proteins do indeed aggregate strongly and that the polypeptides associate to form a dimer or multimeric complex in vivo. These characteristics are consistent with the hypothesis that the 40-kDa and 42-kDa polypeptides are subunits of a multimeric integral membrane protein which has an auxin-binding site, and which may

  19. Proline Substitutions and Threonine Pseudophosphorylation of the SH3 Ligand of 18.5-kDa Myelin Basic Protein Decrease Its Affinity for the Fyn-SH3 Domain and Alter Process Development and Protein Localization in Oligodendrocytes

    PubMed Central

    Smith, Graham S.T.; De Avila, Miguel; Paez, Pablo M.; Spreuer, Vilma; Wills, Melanie K.B.; Jones, Nina; Boggs, Joan M.; Harauz, George

    2012-01-01

    The developmentally regulated myelin basic proteins (MBPs), which arise from the golli (gene of oligodendrocyte lineage) complex, are highly positively charged, intrinsically disordered, multifunctional proteins having several alternatively spliced isoforms and posttranslational modifications, and they play key roles in myelin compaction. The classic 18.5-kDa MBP isoform has a proline-rich region comprising amino acids 92–99 (murine sequence –T92PRTPPPS99–) that contains a minimal SH3 ligand domain. We have previously shown that 18.5-kDa MBP binds to several SH3 domains, including that of Fyn, a member of the Src family of tyrosine kinases involved in a number of signaling pathways during CNS development. To determine the physiological role of this binding as well as the role of phosphorylation of Thr92 and Thr95, in the current study we have produced several MBP variants specifically targeting phosphorylation sites and key structural regions of MBP’s SH3 ligand domain. Using isothermal titration calorimetry, we have demonstrated that, compared with the wild-type protein, these variants have lower affinity for the SH3 domain of Fyn. Moreover, overexpression of N-terminal-tagged GFP versions in immortalized oligodendroglial N19 and N20.1 cell cultures results in aberrant elongation of membrane processes and increased branching complexity and inhibits the ability of MBP to decrease Ca2+ influx. Phosphorylation of Thr92 can also cause MBP to traffic to the nucleus, where it may participate in additional protein–protein interactions. Coexpression of MBP with a constitutively active form of Fyn kinase resulted in membrane process elaboration, a phenomenon that was abolished by point amino acid substitutions in MBP’s SH3 ligand domain. These results suggest that MBP’s SH3 ligand domain plays a key role in intracellular protein interactions in vivo and may be required for proper membrane elaboration of developing oligodendrocytes and, further, that

  20. Identification of Collagen-Binding Proteins in Lactobacillus spp. with Surface-Enhanced Laser Desorption/Ionization–Time of Flight ProteinChip Technology

    PubMed Central

    Howard, Jeffrey C.; Heinemann, Christine; Thatcher, Bradley J.; Martin, Brian; Gan, Bing Siang; Reid, Gregor

    2000-01-01

    Biosurfactants produced by Lactobacillus fermentum RC-14, L. rhamnosus GR-1 and 36, and L. casei Shirota were found to contain proteins that bind to both collagen types III and VI, as determined by surface-enhanced laser desorption/ionization (SELDI)–time of flight mass spectrometry. Both collagen types III and VI immobilized on SELDI preactivated ProteinChip arrays detected several different sizes (2 to 48 kDa) of collagen-binding proteins. Overall, the RC-14-produced biosurfactant contained the greatest number of collagen-binding proteins (RC-14 > GR-1 > 36 > Shirota), including the mature form of a previously cloned 29-kDa collagen-binding protein (referred to in its mature 26-kDa form). Although biosurfactants isolated from L. casei Shirota and L. rhamnosus 36 and GR-1 also contain several collagen-binding proteins, they do not contain the 26-kDa collagen-binding protein. Together, these results demonstrate the utility of the SELDI system as a means of rapidly characterizing clinically important but complex biosurfactant solutions. PMID:11010889

  1. Identification of an intracellular protein that specifically interacts with photoaffinity-labeled oncogenic p21 protein.

    PubMed

    Lee, G; Ronai, Z A; Pincus, M R; Brandt-Rauf, P W; Murphy, R B; Delohery, T M; Nishimura, S; Yamaizumi, Z; Weinstein, I B

    1989-11-01

    An oncogenic 21-kDa (p21) protein (Harvey RAS protein with Val-12) has been covalently modified with a functional reagent that contains a photoactivatable aromatic azide group. This modified p21 protein has been introduced quantitatively into NIH 3T3 cells using an erythrocyte-mediated fusion technique. The introduced p21 protein was capable of inducing enhanced pinocytosis and DNA synthesis in the recipient cells. To identify the putative intracellular protein(s) that specifically interact with the modified p21 protein, the cells were pulsed with [35S]methionine at selected times after fusion and then UV-irradiated to activate the azide group. The resulting nitrene covalently binds to amino acid residues in adjacent proteins, thus linking the p21 protein to these proteins. The cells were then lysed, and the lysate was immunoprecipitated with the anti-p21 monoclonal antibody Y13-259. The immunoprecipitate was analyzed by SDS/PAGE to identify p21-protein complexes. By using this technique, we found that three protein complexes of 51, 64, and 82 kDa were labeled specifically and reproducibly. The most prominent band is the 64-kDa protein complex that shows a time-dependent rise and fall, peaking within a 5-hr period after introduction of the p21 protein into the cells. These studies provide evidence that in vitro the p21 protein becomes associated with a protein whose mass is about 43 kDa. We suggest that the formation of this complex may play a role in mediating early events involved with cell transformation induced by RAS oncogenes.

  2. Identification of an intracellular protein that specifically interacts with photoaffinity-labeled oncogenic p21 protein.

    PubMed Central

    Lee, G; Ronai, Z A; Pincus, M R; Brandt-Rauf, P W; Murphy, R B; Delohery, T M; Nishimura, S; Yamaizumi, Z; Weinstein, I B

    1989-01-01

    An oncogenic 21-kDa (p21) protein (Harvey RAS protein with Val-12) has been covalently modified with a functional reagent that contains a photoactivatable aromatic azide group. This modified p21 protein has been introduced quantitatively into NIH 3T3 cells using an erythrocyte-mediated fusion technique. The introduced p21 protein was capable of inducing enhanced pinocytosis and DNA synthesis in the recipient cells. To identify the putative intracellular protein(s) that specifically interact with the modified p21 protein, the cells were pulsed with [35S]methionine at selected times after fusion and then UV-irradiated to activate the azide group. The resulting nitrene covalently binds to amino acid residues in adjacent proteins, thus linking the p21 protein to these proteins. The cells were then lysed, and the lysate was immunoprecipitated with the anti-p21 monoclonal antibody Y13-259. The immunoprecipitate was analyzed by SDS/PAGE to identify p21-protein complexes. By using this technique, we found that three protein complexes of 51, 64, and 82 kDa were labeled specifically and reproducibly. The most prominent band is the 64-kDa protein complex that shows a time-dependent rise and fall, peaking within a 5-hr period after introduction of the p21 protein into the cells. These studies provide evidence that in vitro the p21 protein becomes associated with a protein whose mass is about 43 kDa. We suggest that the formation of this complex may play a role in mediating early events involved with cell transformation induced by RAS oncogenes. Images PMID:2682656

  3. The 53-kDa proteolytic product of precursor starch-hydrolyzing enzyme of Aspergillus niger has Taka-amylase-like activity.

    PubMed

    Ravi-Kumar, K; Venkatesh, K S; Umesh-Kumar, S

    2007-04-01

    The 53-kDa amylase secreted by Aspergillus niger due to proteolytic processing of the precursor starch-hydrolyzing enzyme was resistant to acarbose, a potent alpha-glucosidase inhibitor. The enzyme production was induced when A. niger was grown in starch medium containing the inhibitor. Antibodies against the precursor enzyme cross-reacted with the 54-kDa Taka-amylase protein of A. oryzae. It resembled Taka-amylase in most of its properties and also hydrolyzed starch to maltose of alpha-anomeric configuration. However, it did not degrade maltotriose formed during the reaction and was not inhibited by zinc ions.

  4. Identification of FBXO25-interacting Proteins Using an Integrated Proteomics Approach

    PubMed Central

    Teixeira, Felipe R.; Yokoo, Sami; Gartner, Carlos G.; Manfiolli, Adriana O.; Baqui, Munira M. A.; Assmann, Eliana M.; Maragno, Ana Leticia G. C.; Yu, Huijun; de Lanerolle, Primal; Kobarg, Jörg; Gygi, Steven P.; Gomes, Marcelo D.

    2011-01-01

    FBXO25 is one of 68 human F-box proteins that serve as specificity factors for a family of ubiquitin ligases composed of Skp1, Rbx1, Cullin1 and F-box protein (SCF1) that are involved in targeting proteins for destruction across the ubiquitin proteasome system. We recently reported that the FBXO25 protein accumulates in novel subnuclear structures named FBXO25-associated nuclear domains (FANDs). Combining two-step affinity purification followed by mass spectrometry with a classical two-hybrid screen, we identified 132 novel potential FBXO25 interacting partners. One of the identified proteins, β-actin, physically interacts through its N-terminus with FBXO25 and is enriched in the FBXO25 nuclear compartments. Inhibitors of actin polymerization promote a significant disruption of FANDs, indicating that they are compartments influenced by the organizational state of actin in the nucleus. Furthermore, FBXO25 antibodies interfered with RNA polymerase II transcription in vitro. Our results open new perspectives for the understanding of this novel compartment and its nuclear functions. PMID:20473970

  5. Purification of a 6.5 kDa protease inhibitor from Amazon Inga umbratica seeds effective against serine proteases of the boll weevil Anthonomus grandis.

    PubMed

    Calderon, L A; Teles, R C L; Leite, J R S A; Franco, O L; Grossi-de-Sá, M F; Medrano, F J; Bloch, C; Freitas, S M

    2005-08-01

    A 6.5 kDa serine protease inhibitor was purified by anion-exchange chromatography from the crude extract of the Inga umbratica seeds, containing inhibitor isoforms ranging from 6.3 to 6.7 kDa and protease inhibitors of approximately 19 kDa. The purified protein was characterized as a potent inhibitor against trypsin and chymotrypsin and it was named I. umbratica trypsin and chymotrypsin inhibitor (IUTCI). MALDI-TOF spectra of the IUTCI, in the presence of DTT, showed six disulfide bonds content, suggesting that this inhibitor belongs to Bowman-Birk family. The circular dichroism spectroscopy indicates that IUTCI is predominantly formed by unordered and beta-sheet secondary structure. It was also characterized, by fluorescence spectroscopy, as a stable protein at range of pH from 5.0 to 7.0. Moreover, this inhibitor at concentration of 75 microM presented a remarkable inhibitory activity (60%) against digestive serine proteases from boll weevil Anthonomus grandis, an important economical cotton pest.

  6. The 70 kDa Heat Shock Protein Assists during the Repair of Chilling Injury in the Insect, Pyrrhocoris apterus

    PubMed Central

    Koštál, Vladimír; Tollarová-Borovanská, Michaela

    2009-01-01

    Background The Pyrrhocoris apterus (Insecta: Heteroptera) adults attain high levels of cold tolerance during their overwintering diapause. Non-diapause reproducing adults, however, lack the capacity to express a whole array of cold-tolerance adaptations and show relatively low survival when exposed to sub-zero temperatures. We assessed the competence of non-diapause males of P. apterus for responding to heat- and cold-stresses by up-regulation of 70 kDa heat shock proteins (Hsps) and the role of Hsps during repair of heat- and cold-induced injury. Principal Findings The fragments of P. apterus homologues of Hsp70 inducible (PaHsp70) and cognate forms (PaHsc70) were cloned and sequenced. The abundance of mRNA transcripts for the inducible form (qPCR) and corresponding protein (Western blotting) were significantly up-regulated in response to high and low temperature stimuli. In the cognate form, mRNA was slightly up-regulated in response to both stressors but very low or no up-regulation of protein was apparent after heat- or cold-stress, respectively. Injection of 695 bp-long Pahsp70 dsRNA (RNAi) caused drastic suppression of the heat- and cold-stress-induced Pahsp70 mRNA response and the up-regulation of corresponding protein was practically eliminated. Our RNAi predictably prevented recovery from heat shock and, in addition, negatively influenced repair of chilling injuries caused by cold stress. Cold tolerance increased when the insects were first exposed to a mild heat shock, in order to trigger the up-regulation of PaHsp70, and subsequently exposed to cold stress. Conclusion Our results suggest that accumulation of PaHsp70 belongs to a complex cold tolerance adaptation in the insect Pyrrhocoris apterus. PMID:19229329

  7. Diverse accumulation of several dehydrin-like proteins in cauliflower (Brassica oleracea var. botrytis), Arabidopsis thaliana and yellow lupin (Lupinus luteus) mitochondria under cold and heat stress.

    PubMed

    Rurek, Michal

    2010-08-18

    Dehydrins represent hydrophilic proteins acting mainly during cell dehydration and stress response. Dehydrins are generally thermostable; however, the so-called dehydrin-like (dehydrin-related) proteins show variable thermolability. Both groups immunoreact with antibodies directed against the K-segment of dehydrins. Plant mitochondrial dehydrin-like proteins are poorly characterized. The purpose of this study was to extend previous reports on plant dehydrins by comparing the level of immunoprecipitated dehydrin-like proteins in cauliflower (Brassica oleracea var. botrytis), Arabidopsis thaliana and yellow lupin (Lupinus luteus) mitochondria under cold and heat stress. All the analyzed plant species showed constitutive accumulation of thermostable mitochondrial putative dehydrins ranging from 50 to 70 kDa. The mitochondrial dehydrin-like proteins observed in cauliflower and Arabidopsis ranged from 10 to 100 kDa and in lupin imbibed seeds and hypocotyls--from 20 to 90 kDa. Cold treatment increased mainly the accumulation of 10-100 kDa cauliflower and Arabidopsis dehydrin-like proteins, in the patterns different in cauliflower leaf and inflorescence mitochondria. However, in lupin mitochondria, cold affected mainly 25-50 kDa proteins and seemed to induce the appearance of some novel dehydrin-like proteins. The influence of frost stress on cauliflower leaf mitochondrial dehydrin- like proteins was less significant. The impact of heat stress was less significant in lupin and Arabidopsis than in cauliflower inflorescence mitochondria. Cauliflower mitochondrial dehydrin-like proteins are localized mostly in the mitochondrial matrix; it seems that some of them may interact with mitochondrial membranes. All the results reveal an unexpectedly broad spectrum of dehydrin-like proteins accumulated during some abiotic stress in the mitochondria of the plant species analyzed. They display only limited similarity in size to those reported previously in maize, wheat and rye

  8. Two forms of Vibrio cholerae O1 El Tor hemolysin derived from identical precursor protein.

    PubMed

    Ikigai, H; Ono, T; Nakae, T; Otsuru, H; Shimamura, T

    1999-01-08

    Vibrio cholerae O1 grown in heart infusion broth produces two forms of El Tor hemolysin (ETH) monomers of 65 and 50 kDa. These monomers form several different sizes of mixed oligomers ranging from 180 to 280 kDa in the liposomal membranes. We found that the N-terminal amino acid sequences, NH2-Trp-Pro-Ala-Pro-Ala-Asn-Ser-Glu, of both the 65- and 50-kDa toxins were identical. We assumed, therefore, that the 65- and 50-kDa toxins were derivatives of the identical precursor protein and the 50-kDa protein was a truncated derivative of 65-kDa ETH. To substantiate this assumption, we treated the 260-kDa oligomer with trypsin and obtained a 190-kDa oligomer. This 190-kDa oligomer consisted of only the 50-kDa subunits. Both 260- and 190-kDa oligomers formed ion channels indistinguishable from each other in planar lipid bilayers. These results suggest that the essential part of the ETH in forming the membrane-damaging aggregate is a 50-kDa protein.

  9. Photoaffinity labelling of the cardiac calcium channel. (-)-[3H]azidopine labels a 165 kDa polypeptide, and evidence against a [3H]-1,4-dihydropyridine-isothiocyanate being a calcium-channel-specific affinity ligand.

    PubMed

    Ferry, D R; Goll, A; Glossmann, H

    1987-04-01

    The arylazide 1,4-dihydropyridine (-)-[3H]azidopine binds to a saturable population of sites in guinea-pig heart membranes with a dissociation constant (KD) of 30 +/- 7 pM and a density (Bmax.) of 670 +/- 97 fmol/mg of protein. This high-affinity binding site is assumed to reside on voltage-operated calcium channels because reversible binding is blocked stereoselectively by 1,4-dihydropyridine channel blockers and by the enantiomers of Bay K 8644. A low-affinity (KD 25 +/- 7 nM) high-capacity (Bmax. 21.6 +/- 9 pmol/mg of protein) site does not bind (-)- or (+)-Bay K 8644, but is blocked by high concentrations (greater than 500 nM) of dihydro-2,6-dimethyl-4-(2-isothiocyanatophenyl)-3,5-pyridinedicarboxy lic acid dimethyl ester (1,4-DHP-isothiocyanate) or, e.g., (+/-)-nicardipine. (-)-[3H]Azidopine was photoincorporated covalently into bands of 165 +/- 8, 39 +/- 2 and 35 +/- 3 kDa, as determined by SDS/polyacrylamide-gel electrophoresis. Labelling of the 165 kDa band is protected stereoselectively by 1,4-dihydropyridine enantiomers at low (nM) concentrations and by (-)- and (+)-Bay K 8644, whereas the lower-Mr bands are not. Thus, only the 165 kDa band is the calcium-channel-linked 1,4-dihydropyridine receptor. Photolabelling of the 39 or 35 kDa bands was only blocked by 10 microM-1,4-DHP-isothiocyanate or 50 microM-(+/-)-nicardipine but not by 10 microM-(-)-Bay K 8644. [3H]-1,4-DHP-isothiocyanate binds to guinea-pig heart membranes with a KD of 0.35 nM and dissociates with a k-1 of 0.2 min-1 at 30 degrees C. [3H]-1,4 DHP-isothiocyanate irreversibly labels bands of 39 and 35 kDa which are protected by greater than 10 microM-(+/-)-nicardipine or unlabelled ligand but not by 10 microM-(-)-Bay K 8644. Thus, [3H]-1,4-DHP-isothiocyanate is not an affinity probe for the calcium channel.

  10. Porins of Pseudomonas fluorescens MFO as fibronectin-binding proteins.

    PubMed

    Rebière-Huët, J; Guérillon, J; Pimenta, A L; Di Martino, P; Orange, N; Hulen, C

    2002-09-24

    Bacterial adherence is a complex phenomenon involving specific interactions between receptors, including matricial fibronectin, and bacterial ligands. We show here that fibronectin and outer membrane proteins of Pseudomonas fluorescens were able to inhibit adherence of P. fluorescens to fibronectin-coated wells. We identified at least six fibronectin-binding proteins with molecular masses of 70, 55, 44, 37, 32 and 28 kDa. The presence of native (32 kDa) and heat-modified forms (37 kDa) of OprF was revealed by immuno-analysis and the 44-kDa band was composed of three proteins, their N-terminal sequences showing homologies with Pseudomonas aeruginosa porins (OprD, OprE1 and OprE3).

  11. Nuclear translocation of the 1,25D{sub 3}-MARRS (membrane associated rapid response to steroids) receptor protein and NF{kappa}B in differentiating NB4 leukemia cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, Wenqing; Beilhartz, Greg; Roy, Yvette

    2010-04-15

    1,25 Dihydroxyvitamin D{sub 3} (1,25D{sub 3}) primes NB4 promyelocytic leukemia cells to differentiate along the monocyte/macrophage lineage through a non-genomic mechanism. Here we show that NB4 cells express high levels of the recently identified membrane receptor for 1,25D{sub 3}, which is a distinct gene product from the classical nuclear vitamin D receptor. This 57 kDa protein, named 1,25D{sub 3}-MARRS (Membrane Activated Rapid Response to Steroids)/ERp57/PIA3 appears to associate in a complex with the transcription factor, nuclear factor kappa B (NF{kappa}B). In unstimulated cells, 1,25D{sub 3}-MARRS can be co-immunoprecipitated with antibodies directed at NF{kappa}B, and NF{kappa}B is co-precipitated when antibodies againstmore » 1,25D{sub 3}-MARRS or ERp57 are used. Confocal microscopy and subcellular fractionation studies demonstrate that both 1,25D{sub 3}-MARRS and NF{kappa}B begin translocating to the nucleus within minutes of co-stimulation with 1,25D{sub 3} and phorbol ester. The predominant nuclear localization of both proteins precedes the expression of the monocyte/macrophage phenotype and suggests that this event may be critical to the differentiation pathway. This suggests a role for 1,25D{sub 3}-MARRS in the nucleus as a regulator of gene expression. Here it may also regulate the activity of NF{kappa}B and other factors with which it may be interacting.« less

  12. Fibroblast growth factor regulates insulin-like growth factor-binding protein production by vascular smooth muscle cells.

    PubMed

    Ververis, J; Ku, L; Delafontaine, P

    1994-02-01

    Insulin-like growth factor I is an important mitogen for vascular smooth muscle cells, and its effects are regulated by several binding proteins. Western ligand blotting of conditioned medium from rat aortic smooth muscle cells detected a 24 kDa binding protein and a 28 kDa glycosylated variant of this protein, consistent with insulin-like growth factor binding protein-4 by size. Low amounts of a glycosylated 38 to 42 kDa doublet (consistent with binding protein-3) and a 31 kDa non-glycosylated protein also were present. Basic fibroblast growth factor markedly increased secretion of the 24 kDa binding protein and its 28 kDa glycosylated variant. This effect was dose- and time-dependent and was inhibited by co-incubation with cycloheximide. Crosslinking of [125I]-insulin-like growth factor I to cell monolayers revealed no surface-associated binding proteins, either basally or after agonist treatment. Induction of binding protein production by fibroblast growth factor at sites of vascular injury may be important in vascular proliferative responses in vivo.

  13. Developmental and diurnal expression of the synaptosomal-associated protein 25 (Snap25) in the rat pineal gland.

    PubMed

    Karlsen, Anna S; Rath, Martin F; Rohde, Kristian; Toft, Trine; Møller, Morten

    2013-06-01

    Snap25 (synaptosomal-associated protein) is a 25 kDa protein, belonging to the SNARE-family (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) of proteins, essential for synaptic and secretory vesicle exocytosis. Snap25 has by immunohistochemistry been demonstrated in the rat pineal gland but the biological importance of this is unknown. In this study, we demonstrate a high expression of mRNA encoding Snap25 in all parts of the rat pineal complex, the superficial-, and deep-pineal gland, as well as in the pineal stalk. Snap25 showed a low pineal expression during embryonic stages with a strong increase in expression levels just after birth. The expression showed no day/night variations. Neither removal of the sympathetic input to the pineal gland by superior cervical ganglionectomy nor bilateral decentralization of the superior cervical ganglia significantly affected the expression of Snap25 in the gland. The pineal expression levels of Snap25 were not changed following intraperitoneal injection of isoproterenol. The strong expression of Snap25 in the pineal gland suggests the presence of secretory granules and microvesicles in the rat pinealocyte supporting the concept of a vesicular release. At the transcriptional level, this Snap25-based release mechanism does not exhibit any diurnal rhythmicity and is regulated independently of the sympathetic nervous input to the gland.

  14. The purification and characterization of an 88-kDa Porphyromonas endodontalis 35406 protease.

    PubMed

    Rosen, G; Shoshani, M; Naor, R; Sela, M N

    2001-12-01

    A Porphyromonas endodontalis ATCC 35406 protease was purified from Triton X-114 cell extracts by preparative SDS-PAGE followed by electroelution. The purified enzyme exhibits a molecular size of 88 kDa and was dissociated into two polypeptides of 43 and 41 kDa upon heating in the presence of sodium dodecyl sulfate with or without a reducing agent. The protease (pH optimum 7.5-8.0) degraded the extracellular matrix proteins fibrinogen and fibronectin. Collagen IV was also degraded at 37 degrees C but not at 28 degrees C. The protease also cleaved the bioactive peptide angiotensin at amino acid residue phenylalanine-8 and tyrosine-4 but failed to hydrolyze bradykinin, vasopressin and synthetic chromogenic substrates with phenylalanine or tyrosine at the P1 position. In addition, two peptidases were detected in P. endodontalis cells: a proline aminopeptidase that remained associated with the cell pellet after detergent extraction and peptidase/s that partitioned into the Triton X-114 phase after phase separation and degraded the bioactive peptides bradykinin and vasopressin. These P. endodontalis peptidases and proteases may play an important role in both the nutrition and pathogenicity of these assacharolytic microorganisms. The inactivation of bioactive peptides and degradation of extracellular matrix proteins by bacterial enzymes may contribute to the damage of host tissues accompanied with endodontic infections.

  15. Hydrogen/deuterium exchange mass spectrometry with top-down electron capture dissociation for characterizing structural transitions of a 17 kDa protein.

    PubMed

    Pan, Jingxi; Han, Jun; Borchers, Christoph H; Konermann, Lars

    2009-09-09

    Amide H/D exchange (HDX) mass spectrometry (MS) is widely used for protein structural studies. Traditionally, this technique involves protein labeling in D(2)O, followed by acid quenching, proteolytic digestion, and analysis of peptide deuteration levels by HPLC/MS. There is great interest in the development of alternative HDX approaches involving the top-down fragmentation of electrosprayed protein ions, instead of relying on enzymatic cleavage and solution-phase separations. A number of recent studies have demonstrated that electron capture dissociation (ECD) results in fragmentation of gaseous protein ions with little or no H/D scrambling. However, the successful application of this approach for in-depth protein conformational studies has not yet been demonstrated. The current work uses horse myoglobin as a model system for assessing the suitability of HDX-MS with top-down ECD for experiments of this kind. It is found that ECD can pinpoint the locations of protected amides with an average resolution of less than two residues for this 17 kDa protein. Native holo-myoglobin (hMb) shows considerable protection from exchange in all of its helices, whereas loops are extensively deuterated. Fraying is observable at some helix termini. Removal of the prosthetic heme group from hMb produces apo-myoglobin (aMb). Both hMb and aMb share virtually the same HDX protection pattern in helices A-E, whereas helix F is unfolded in aMb. In addition, destabilization is evident for some residues close to the beginning of helix G, the end of helix H, and the C-terminus of the protein. The structural changes reported herein are largely consistent with earlier NMR data for sperm whale myoglobin, although small differences between the two systems are evident. Our findings demonstrate that the level of structural information obtainable with top-down ECD for small to medium-sized proteins considerably surpasses that of traditional HDX-MS experiments, while at the same time greatly reducing

  16. Composition, Protein Profile and Rheological Properties of Pseudocereal-Based Protein-Rich Ingredients.

    PubMed

    Alonso-Miravalles, Loreto; O'Mahony, James A

    2018-05-07

    The objectives of this study were to investigate the nutrient composition, protein profile, morphology, and pasting properties of protein-rich pseudocereal ingredients (quinoa, amaranth, and buckwheat) and compare them to the more common rice and maize flours. Literature concerning protein-rich pseudocereal ingredients is very limited, mainly to protein profiling. The concentrations of macronutrients (i.e., ash, fat, and protein, as well as soluble, insoluble and total dietary fibre) were significantly higher for the protein-rich variants of pseudocereal-based flours than their regular protein content variants and the rice and maize flours. On profiling the protein component using sodium dodecyl sulfate⁻polyacrylamide gel electrophoresis (SDS-PAGE), all samples showed common bands at ~50 kDa and low molecular weight bands corresponding to the globulin fraction (~50 kDa) and albumin fraction (~10 kDa), respectively; except rice, in which the main protein was glutelin. The morphology of the starch granules was studied using scanning electron microscopy with quinoa and amaranth showing the smallest sized granules, while buckwheat, rice, and maize had the largest starch granules. The pasting properties of the ingredients were generally similar, except for buckwheat and amaranth, which showed the highest and lowest final viscosity, respectively. The results obtained in this study can be used to better understand the functionality and food applications of protein-rich pseudocereal ingredients.

  17. Developmentally regulated switch in alternatively spliced SNAP-25 isoforms alters facilitation of synaptic transmission.

    PubMed

    Bark, Christina; Bellinger, Frederick P; Kaushal, Ashutosh; Mathews, James R; Partridge, L Donald; Wilson, Michael C

    2004-10-06

    Although the basic molecular components that promote regulated neurotransmitter release are well established, the contribution of these proteins as regulators of the plasticity of neurotransmission and refinement of synaptic connectivity during development is elaborated less fully. For example, during the period of synaptic growth and maturation in brain, the expression of synaptosomal protein 25 kDa (SNAP-25), a neuronal t-SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) essential for action potential-dependent neuroexocytosis, is altered through alternative splicing of pre-mRNA transcripts. We addressed the role of the two splice-variant isoforms of SNAP-25 with a targeted mouse mutation that impairs the shift from SNAP-25a to SNAP-25b. Most of these mutant mice die between 3 and 5 weeks of age, which coincides with the time when SNAP-25b expression normally reaches mature levels in brain and synapse formation is essentially completed. The altered expression of these SNAP-25 isoforms influences short-term synaptic function by affecting facilitation but not the initial probability of release. This suggests that mechanisms controlling alternative splicing between SNAP-25 isoforms contribute to a molecular switch important for survival that helps to guide the transition from immature to mature synaptic connections, as well as synapse regrowth and remodeling after neural injury.

  18. [Tripartite-motif protein 25 and pyruvate kinase M2 protein expression in non-small cell lung cancer].

    PubMed

    Jing, Huai-Zhi; Qiu, Feng; Chen, Shi-Zhi; Su, Lin; Qu, Can

    2015-03-01

    To investigate the expression of tripartite-motif protein 25 (TRIM25) and pyruvate kinase M2 (PKM2) protein in non-small cell lung cancer (NSCLC) and explore their role in the occurrence and progression of NSCLC. The expressions of TRIM25 and PKM2 protein were detected in 60 NSCLC specimens and 20 adjacent normal lung tissue (>5 cm from the lesions) with immunofluorescence histochemical method and in 10 fresh specimens of NSCLC with Western blotting. The results were analyzed in relation with the clinicopathological features of the patients. The positivity rates of TRIM25 expression was 45% in the 60 lung carcinoma specimens, significantly higher than that in the 20 normal lung tissues (10%, P=0.005). TRIM25 protein was expressed in 28.6% of lung adenocarcinoma tissues and in 59.4% of squamous carcinoma tissues (P=0.017). TRIM25 protein expression was positively correlated with the TNM stages and lymph node metastasis of NSCLC (P<0.05). The expressions of PKM2 protein in 60 cases of lung carcinoma was 73.3%,while in 20 cases of normal lung tissues the expressions was 30%(P=0.001). The positivity rates of PKM2 expression differed significantly between lung adenocarcinoma and squamous carcinoma (57.1% vs 87.5%, P=0.008). An inverse correlation was noted between TRIM25 and PKM2 expressions (P=0.026). TRIM25 and PKM2 protein may participate in the occurrence and progression of NSCLC, and their expressions are inversely correlated.

  19. Molecular and Structural Characterization of the Tegumental 20.6-kDa Protein in Clonorchis sinensis as a Potential Druggable Target.

    PubMed

    Kim, Yu-Jung; Yoo, Won Gi; Lee, Myoung-Ro; Kang, Jung-Mi; Na, Byoung-Kuk; Cho, Shin-Hyeong; Park, Mi-Yeoun; Ju, Jung-Won

    2017-03-04

    The tegument, representing the membrane-bound outer surface of platyhelminth parasites, plays an important role for the regulation of the host immune response and parasite survival. A comprehensive understanding of tegumental proteins can provide drug candidates for use against helminth-associated diseases, such as clonorchiasis caused by the liver fluke Clonorchis sinensis . However, little is known regarding the physicochemical properties of C. sinensis teguments. In this study, a novel 20.6-kDa tegumental protein of the C. sinensis adult worm (CsTegu20.6) was identified and characterized by molecular and in silico methods. The complete coding sequence of 525 bp was derived from cDNA clones and encodes a protein of 175 amino acids. Homology search using BLASTX showed CsTegu20.6 identity ranging from 29% to 39% with previously-known tegumental proteins in C. sinensis . Domain analysis indicated the presence of a calcium-binding EF-hand domain containing a basic helix-loop-helix structure and a dynein light chain domain exhibiting a ferredoxin fold. We used a modified method to obtain the accurate tertiary structure of the CsTegu20.6 protein because of the unavailability of appropriate templates. The CsTegu20.6 protein sequence was split into two domains based on the disordered region, and then, the structure of each domain was modeled using I-TASSER. A final full-length structure was obtained by combining two structures and refining the whole structure. A refined CsTegu20.6 structure was used to identify a potential CsTegu20.6 inhibitor based on protein structure-compound interaction analysis. The recombinant proteins were expressed in Escherichia coli and purified by nickel-nitrilotriacetic acid affinity chromatography. In C. sinensis , CsTegu20.6 mRNAs were abundant in adult and metacercariae, but not in the egg. Immunohistochemistry revealed that CsTegu20.6 localized to the surface of the tegument in the adult fluke. Collectively, our results contribute to a

  20. Plasmodium vivax: a monoclonal antibody recognizes a circumsporozoite protein precursor on the sporozoite surface.

    PubMed

    Gonzalez-Ceron, L; Rodriguez, M H; Wirtz, R A; Sina, B J; Palomeque, O L; Nettel, J A; Tsutsumi, V

    1998-11-01

    The major surface circumsporozoite (CS) proteins are known to play a role in malaria sporozoite development and invasion of invertebrate and vertebrate host cells. Plasmodium vivax CS protein processing during mosquito midgut oocyst and salivary gland sporozoite development was studied using monoclonal antibodies which recognize different CS protein epitopes. Monoclonal antibodies which react with the CS amino acid repeat sequences by ELISA recognized a 50-kDa precursor protein in immature oocyst and additional 47- and 42-kDa proteins in older oocysts. A 42-kDa CS protein was detected after initial sporozoite invasion of mosquito salivary glands and an additional 50-kDa precursor CS protein observed later in infected salivary glands. These data confirm previous results with other Plasmodium species, in which more CS protein precursors were detected in oocysts than in salivary gland sporozoites. A monoclonal antibody (PvPCS) was characterized which reacts with an epitope found only in the 50-kDa precursor CS protein. PvPCS reacted with all P. vivax sporozoite strains tested by indirect immunofluorescent assay, homogeneously staining the sporozoite periphery with much lower intensity than that produced by anti-CS repeat antibodies. Immunoelectron microscopy using PvPCS showed that the CS protein precursor was associated with peripheral cytoplasmic vacuoles and membranes of sporoblast and budding sporozoites in development oocysts. In salivary gland sporozoites, the CS protein precursor was primarily associated with micronemes and sporozoite membranes. Our results suggest that the 50-kDa CS protein precursor is synthesized intracellularly and secreted on the membrane surface, where it is proteolytically processed to form the 42-kDa mature CS protein. These data indicate that differences in CS protein processing in oocyst and salivary gland sporozoites development may occur. Copyright 1998 Academic Press.

  1. Identification of 50- and 23-/25-kDa HeLa cell membrane glycoproteins involved in poliovirus infection: occurrence of poliovirus specific binding sites on susceptible and nonsusceptible cells.

    PubMed

    Barnert, R H; Zeichhardt, H; Habermehl, K O

    1992-02-01

    Glycoproteins in the range 50 and 23/25 kDa were identified as poliovirus specific binding sites on HeLa cells with the monoclonal antibody mAb 122. mAb 122 is characterized by its partial inhibiting effect on poliovirus reproduction and adsorption when prebound to HeLa cells. The binding sites are endocytosed in native cells and specific for poliovirus as mAb 122 did not interfere with the adsorption of human rhinovirus type 14 (HRV 14). The poliovirus binding sites are present also on nonprimate so called nonsusceptible cells, e.g., mouse L-cells, as could be shown with sensitive ELISA based binding assays and performance of binding studies with fixed cells at 37 degrees.

  2. Increased neuronal beta-amyloid precursor protein expression in human temporal lobe epilepsy: association with interleukin-1 alpha immunoreactivity.

    PubMed

    Sheng, J G; Boop, F A; Mrak, R E; Griffin, W S

    1994-11-01

    Levels of immunoreactive beta-amyloid precursor protein and interleukin-1 alpha were found to be elevated in surgically resected human temporal lobe tissue from patients with intractable epilepsy compared with postmortem tissue from neurologically unaffected patients (controls). In tissue from epileptics, the levels of the 135-kDa beta-amyloid precursor protein isoform were elevated to fourfold (p < 0.05) those of controls and those of the 130-kDa isoform to threefold (p < 0.05), whereas those of the 120-kDa isoform (p > 0.05) were not different from control values. beta-Amyloid precursor protein-immunoreactive neurons were 16 times more numerous, and their cytoplasm and proximal processes were more intensely immunoreactive in tissue sections from epileptics than controls (133 +/- 12 vs. 8 +/- 3/mm2; p < 0.001). However, neither beta-amyloid precursor protein-immunoreactive dystrophic neurites nor beta-amyloid deposits were found in this tissue. Interleukin-1 alpha-immunoreactive cells (microglia) were three times more numerous in epileptics than in controls (80 +/- 8 vs. 25 +/- 5/mm2; p < 0.001), and these cells were often found adjacent to beta-amyloid precursor protein-immunoreactive neuronal cell bodies. Our findings, together with functions established in vitro for interleukin-1, suggest that increased expression of this protein contributes to the increased levels of beta-amyloid precursor protein in epileptics, thus indicating a potential role for both of these proteins in the neuronal dysfunctions, e.g., hyperexcitability, characteristic of epilepsy.

  3. Isolation and characterization of a 66-kDa protein from rat liver plasma membrane with RhoA-stimulated phospholipase D activity.

    PubMed

    Dunkirk, Shawn G; Wallert, Mark A; Baumgartner, Matt L; Provost, Joseph J

    2002-02-01

    A 66-kDa molecular weight protein with phospholipase D activity was solubilized and partially purified from rat liver plasma membrane. The activity and regulation of this phospholipase D have been characterized. Immunoblot analyses indicated that the enzyme was distinct from hPLD1 and PLD2, but was recognized by an antibody to the 12 terminal amino acids of PLD1. PLD activity was stimulated by 1-100 microM Ca(2+) and Mg(2+) and displayed a pH optimum of 7.5. Activity was inhibited by both saturated and unsaturated fatty acids. This PLD was activated in an ATP-independent manner by the PKC isozymes alpha and betaII but not activated by other PKC isozymes. It was also stimulated by the small G-proteins RhoA and ARF. RhoA stimulated the greatest activation, followed by ARF and PKC(alpha). This enzyme was further activated in a synergistic manner when combinations of PKC(alpha) and RhoA or ARF were used. This enzyme displayed a greater response activation by RhoA than to activation by ARF. While a potential breakdown product of PLD1, activation by RhoA indicates that the PLD characterized here is distinct from the other PLDs cloned or isolated to date. Copyright 2002 Elsevier Science (USA).

  4. [Serological and cellular reactivity to mycobacterial proteins in Hansen's disease].

    PubMed

    Rada, Elsa; Aranzazu, Nacarid; Rodríguez, Vestalia; Borges, Rafael; Convit, Jacinto

    2010-09-01

    The study was designed for evaluating immunological reactivity to various mycobacterial protein preparations using serological and cell-mediated immunological tests in patients with clinical leprosy signs, predominantly, with the multibacillary forms. All patients were adults with ages between 20 and 30 years. Fifty eight (n = 81) percent corresponded to Lepromatous Leprosy (LL), 29% (n = 41) to Borderline Lepromatous Leprosy (BL) and 10% (n = 41) to Borderline Borderline Leprosy (BB); only 3% were Borderline Tuberculoid (BT) patients: 74% males and 26% females. The most frequent reactional phenomenon was of the Erythema Nodosum (ENL) type. The mycobacterial proteins tested were: total crude Mycobacterium leprae antigens (MISA); Mycobacterium bovis (MbSA and excretion MbSA); partially purified excretion protein antigen, with a 30 kDa relative movility (Ml30); and recombinant M. leprae proteins (Mt70, Mb 65, Ml 36, 28, 18 and 10 kDa). Two of the recombinant proteins (Ml10 and Ml 36 kDa) presented a statiscally significant higher serological reactivity, directly related with a larger bacillary load (p = 0.0051 and 0.050 respectively). The 30 kDa protein was predominantly recognized by antibodies from multibacillary patients. Results show that mean antibody values were higher in non reactional patients when tested against complete proteins (MbSA and ex MbSA) when compared with the group of patients who presented reactional phenomena (p = 0.000567 and 0.000061, respectively). Comparing reactional with non reactional patients, it was seen that mean antibody values against complete proteins (MbSA and ex MbSA) were higher in non reactional individuals (p = 0.000567 and 0.000061, respectively). This same behavior occurred towards individual mycobacterial proteins (30, 10 and 36 kDa). The T lymphocyte prolypherative response in reactional and non reactional patients towards mycobacterial proteins (MlSA, Ml 10 kDa, MbSA, ex MbSA) was negative.

  5. Redox changes accompanying storage protein mobilization in moist chilled and warm incubated walnut kernels prior to germination.

    PubMed

    Shahmoradi, Zeynab; Tamaskani, Fatemeh; Sadeghipour, Hamid Reza; Abdolzadeh, Ahmad

    2013-01-01

    Alterations in the redox state of storage proteins and the associated proteolytic processes were investigated in moist-chilled and warm-incubated walnut (Juglans regia L.) kernels prior to germination. The kernel total protein labeling with a thiol-specific fluorochrome i.e. monobromobimane (mBBr) revealed more reduction of 29-32 kDa putative glutelins, while in the soluble proteins, both putative glutelins and 41, 55 and 58 kDa globulins contained reduced disulfide bonds during mobilization. Thus, the in vivo more reduced disulfide bonds of storage proteins corresponds to greater solubility. After the in vitro reduction of walnut kernel proteins pre-treated by N-ethyl maleimide (NEM) with dithioerythrethiol (DTT) and bacterial thioredoxin, the 58 kDa putative globulin and a 6 kDa putative albumin were identified as disulfide proteins. Thioredoxin stimulated the reduction of the H(2)O(2)-oxidized 6 kDa polypeptide, but not the 58 kDa polypeptide by DTT. The solubility of 6 kDa putative albumin, 58 and 19-24 kDa putative globulins and glutelins, respectively, were increased by DTT. The in vitro specific mobilization of the 58 kDa polypeptide that occurred at pH 5.0 by the kernel endogenous protease was sensitive to the serine-protease inhibitor phenylmethylsulfonyl fluoride (PMSF) and stimulated by DTT. The specific degradation of the 58 kDa polypeptide might be achieved through thioredoxin-mediated activation of a serine protease and/or reductive unfolding of its 58 kDa polypeptide substrate. As redox changes in storage proteins occurred equally in both moist chilled and warm incubated walnut kernels, the regulatory functions of thioredoxins in promoting seed germination may be due to other germination related processes. Copyright © 2012 Elsevier GmbH. All rights reserved.

  6. Interaction of human platelets with laminin and identification of the 67 kDa laminin receptor on platelets.

    PubMed Central

    Tandon, N N; Holland, E A; Kralisz, U; Kleinman, H K; Robey, F A; Jamieson, G A

    1991-01-01

    A microtitre adhesion assay has been developed to define parameters affecting the adherence of washed platelets to laminin. Adherence was optimally supported by Mg2+ and was inhibited by Ca2+ and by anti-laminin Fab fragments, but significant adhesion (75-90% of control) was found both in heparinized plasma containing physiological levels of bivalent cations and in plasma anti-coagulated with EGTA. Adherence was unaffected by platelet activation with ADP but was decreased by 50% by treatment with alpha-thrombin (1 unit/ml, 5 min). Adherence was unaffected by monospecific polyclonal antibodies to glycoprotein (GP) Ib and GPIV, and was normal with platelets from two patients with Glanzmann's thrombasthaenia, indicating that GPIb, the GPIIb/IIIa complex and GPIV are not involved in platelet-laminin interaction. Affinity chromatography of Triton-solubilized membranes on laminin-Sepharose followed by elution with 0.2 M-glycine/HCl (pH 2.85) identified a major band with a molecular mass of 67 kDa in the reduced and of 53 kDa in the unreduced form. This protein gave a positive reaction on Western blotting with a monospecific polyclonal antibody raised against the high-affinity laminin receptor isolated from human breast carcinoma tissue. The adhesion of platelets to laminin was inhibited by two monoclonal IgM antibodies specific to the LR-1 domain of the 67 kDa receptor. The binding protein was surface-oriented, as shown by flow cytofluorimetry and by the fact that it could be iodinated in intact platelets, but it was not labelled by the periodate-borotritide procedure, suggesting that it did not contain terminal sialic acid. The laminin-derived peptides Tyr-Ile-Gly-Ser-Arg and Cys-Asp-Pro-Gly-Tyr-Ile-Gly-Ser-Arg-NH2, which constitute a complementary binding domain in laminin for the 67 kDa receptor, themselves supported platelet adhesion, bound to the receptor and inhibited the adhesion of platelets to laminin. In addition, Fab fragments of anti

  7. Plasma proteins of rainbow trout (Oncorhynchus mykiss) isolated by binding to lipopolysaccharide from Aeromonas salmonicida.

    PubMed

    Hoover, G J; el-Mowafi, A; Simko, E; Kocal, T E; Ferguson, H W; Hayes, M A

    1998-07-01

    In an attempt to find plasma proteins that might be involved in the constitutive resistance of rainbow trout to furunculosis, a disease caused by Aeromonas salmonicida (AS), we purified serum and plasma proteins based on their calcium- and carbohydrate-dependent affinity for A. salmonicida lipopolysaccharide (LPS) coupled to an epoxy-activated synthetic matrix (Toyopearl AF Epoxy 650M). A multimeric family of high molecular weight (96 to 200-kDa) LPS-binding proteins exhibiting both calcium and mannose dependent binding was isolated. Upon reduction the multimers collapsed to subunits of approximately 16-kDa as estimated by 1D-PAGE and exhibited pI values of 5.30 and 5.75 as estimated from 2D-PAGE. Their N-terminal sequences were related to rainbow trout ladderlectin (RT-LL), a Sepharose-binding protein. Polyclonal antibodies to the LPS-purified 16-kDa subunits recognized both the reduced 16-kDa subunits and the non-reduced multimeric forms. A calcium- and N-acetylglucosamine (GlcNAc)-dependent LPS-binding multimeric protein (approximately 207-kDa) composed of 34.5-kDa subunits was purified and found to be identical to trout serum amyloid P (SAP) by N-terminal sequence (DLQDLSGKVFV). A protein of 24-kDa, in reduced and non-reduced conditions, was isolated and had N-terminal sequence identity with a known C-reactive protein (CRP) homologue, C-polysaccharide-binding protein 2 (TCBP2) of rainbow trout. A novel calcium-dependent LPS-binding protein was purified and termed rainbow trout lectin 37 (RT-L37). This protein, composed of dimers, tetramers and pentamers of 37 kDa subunits (pI 5.50-6.10) with N-terminal sequence (IQE(D/N)GHAEAPGATTVLNEILR) showed no close homology to proteins known or predicted from cDNA sequences. These findings demonstrate that rainbow trout have several blood proteins with lectin properties for the LPS of A. salmonicida; the biological functions of these proteins in resistance to furunculosis are still unknown.

  8. Diverse accumulation of several dehydrin-like proteins in cauliflower (Brassica oleracea var. botrytis), Arabidopsis thaliana and yellow lupin (Lupinus luteus) mitochondria under cold and heat stress

    PubMed Central

    2010-01-01

    Background Dehydrins represent hydrophilic proteins acting mainly during cell dehydration and stress response. Dehydrins are generally thermostable; however, the so-called dehydrin-like (dehydrin-related) proteins show variable thermolability. Both groups immunoreact with antibodies directed against the K-segment of dehydrins. Plant mitochondrial dehydrin-like proteins are poorly characterized. The purpose of this study was to extend previous reports on plant dehydrins by comparing the level of immunoprecipitated dehydrin-like proteins in cauliflower (Brassica oleracea var. botrytis), Arabidopsis thaliana and yellow lupin (Lupinus luteus) mitochondria under cold and heat stress. Results All the analyzed plant species showed constitutive accumulation of thermostable mitochondrial putative dehydrins ranging from 50 to 70 kDa. The mitochondrial dehydrin-like proteins observed in cauliflower and Arabidopsis ranged from 10 to 100 kDa and in lupin imbibed seeds and hypocotyls - from 20 to 90 kDa. Cold treatment increased mainly the accumulation of 10-100 kDa cauliflower and Arabidopsis dehydrin-like proteins, in the patterns different in cauliflower leaf and inflorescence mitochondria. However, in lupin mitochondria, cold affected mainly 25-50 kDa proteins and seemed to induce the appearance of some novel dehydrin-like proteins. The influence of frost stress on cauliflower leaf mitochondrial dehydrin- like proteins was less significant. The impact of heat stress was less significant in lupin and Arabidopsis than in cauliflower inflorescence mitochondria. Cauliflower mitochondrial dehydrin-like proteins are localized mostly in the mitochondrial matrix; it seems that some of them may interact with mitochondrial membranes. Conclusions All the results reveal an unexpectedly broad spectrum of dehydrin-like proteins accumulated during some abiotic stress in the mitochondria of the plant species analyzed. They display only limited similarity in size to those reported previously

  9. Probing the size of proteins with glass nanopores

    NASA Astrophysics Data System (ADS)

    Steinbock, L. J.; Krishnan, S.; Bulushev, R. D.; Borgeaud, S.; Blokesch, M.; Feletti, L.; Radenovic, A.

    2014-11-01

    Single molecule studies using nanopores have gained attention due to the ability to sense single molecules in aqueous solution without the need to label them. In this study, short DNA molecules and proteins were detected with glass nanopores, whose sensitivity was enhanced by electron reshaping which decreased the nanopore diameter and created geometries with a reduced sensing length. Further, proteins having molecular weights (MW) ranging from 12 kDa to 480 kDa were detected, which showed that their corresponding current peak amplitude changes according to their MW. In the case of the 12 kDa ComEA protein, its DNA-binding properties to an 800 bp long DNA molecule was investigated. Moreover, the influence of the pH on the charge of the protein was demonstrated by showing a change in the translocation direction. This work emphasizes the wide spectrum of detectable molecules using nanopores from glass nanocapillaries, which stand out because of their inexpensive, lithography-free, and rapid manufacturing process.Single molecule studies using nanopores have gained attention due to the ability to sense single molecules in aqueous solution without the need to label them. In this study, short DNA molecules and proteins were detected with glass nanopores, whose sensitivity was enhanced by electron reshaping which decreased the nanopore diameter and created geometries with a reduced sensing length. Further, proteins having molecular weights (MW) ranging from 12 kDa to 480 kDa were detected, which showed that their corresponding current peak amplitude changes according to their MW. In the case of the 12 kDa ComEA protein, its DNA-binding properties to an 800 bp long DNA molecule was investigated. Moreover, the influence of the pH on the charge of the protein was demonstrated by showing a change in the translocation direction. This work emphasizes the wide spectrum of detectable molecules using nanopores from glass nanocapillaries, which stand out because of their

  10. 70-kDa Heat Shock Cognate Protein hsc70 Mediates Calmodulin-dependent Nuclear Import of the Sex-determining Factor SRY*

    PubMed Central

    Kaur, Gurpreet; Lieu, Kim G.; Jans, David A.

    2013-01-01

    We recently showed that the developmentally important family of SOX (SRY (sex determining region on the Y chromosome)-related high mobility group (HMG) box) proteins require the calcium-binding protein calmodulin (CaM) for optimal nuclear accumulation, with clinical mutations in SRY that specifically impair nuclear accumulation via this pathway resulting in XY sex reversal. However, the mechanism by which CaM facilitates nuclear accumulation is unknown. Here, we show, for the first time, that the 70-kDa heat shock cognate protein hsc70 plays a key role in CaM-dependent nuclear import of SRY. Using a reconstituted nuclear import assay, we show that antibodies to hsc70 significantly reduce nuclear accumulation of wild type SRY and mutant derivatives thereof that retain CaM-dependent nuclear import, with an increased rate of nuclear accumulation upon addition of both CaM and hsc70, in contrast to an SRY mutant derivative with impaired CaM binding. siRNA knockdown of hsc70 in intact cells showed similar results, indicating clear dependence upon hsc70 for CaM-dependent nuclear import. Analysis using the technique of fluorescence recovery after photobleaching indicated that hsc70 is required for the maximal rate of SRY nuclear import in living cells but has no impact upon SRY nuclear retention/nuclear dynamics. Finally, we demonstrate direct binding of hsc70 to the SRY·CaM complex, with immunoprecipitation experiments from cell extracts showing association of hsc70 with wild type SRY, but not with a mutant derivative with impaired CaM binding, dependent on Ca2+. Our novel findings strongly implicate hsc70 in CaM-dependent nuclear import of SRY. PMID:23235156

  11. Molecular cloning of low-temperature-inducible ribosomal proteins from soybean.

    PubMed

    Kim, Kee-Young; Park, Seong-Whan; Chung, Young-Soo; Chung, Chung-Han; Kim, Jung-In; Lee, Jai-Heon

    2004-05-01

    Three ribosomal protein genes induced by low-temperature treatment were isolated from soybean. GmRPS13 (742 bp) encodes a 17.1 kDa protein which has 95% identity with the 40S ribosomal protein S13 of Panax ginseng (AB043974). GmRPS6 (925 bp) encodes a 28.1 kDa protein which has 94% identity with the 40S ribosomal protein S6 of Asparagus officinalis (AJ277533). GmRPL37 (494 bp) encodes a 10.7 kDa protein which has 85% identity with the 60S ribosomal protein L37 of Arabidopsis thaliana (AF370216). The expression of these ribosomal protein genes started to increase 3 d after low-temperature treatment, whereas the cold-stress protein src1 was highly induced from the first day. Such late response of these ribosomal protein genes may be due to secondary signals during cold adaptation. The induction of ribosomal protein genes might enhance the translation process or help proper ribosome functioning under low-temperature conditions.

  12. Prostatic origin of a zinc binding high molecular weight protein complex in human seminal plasma.

    PubMed

    Siciliano, L; De Stefano, C; Petroni, M F; Vivacqua, A; Rago, V; Carpino, A

    2000-03-01

    The profile of the zinc ligand high molecular weight proteins was investigated in the seminal plasma of 55 normozoospermic subjects by size exclusion high performance liquid chromatography (HPLC). The proteins were recovered from Sephadex G-75 gel filtration of seminal plasma in three zinc-containing fractions which were then submitted to HPLC analysis. The results were, that in all the samples, the protein profiles showed two peaks with apparent molecular weight of approximately 660 and approximately 250 kDa. Dialysis experiments revealed that both approximately 660 and approximately 250 kDa proteins were able to uptake zinc against gradient indicating their zinc binding capacity. The HPLC analysis of the whole seminal plasma evidenced only the approximately 660 kDa protein complex as a single well quantifying peak, furthermore a positive correlation between its peak area and the seminal zinc values (P < 0.001) was observed. This suggested a prostatic origin of the approximately 660 kDa protein complex which was then confirmed by the seminal plasma HPLC analysis of a subject with agenesis of the Wolffian ducts. Finally the study demonstrated the presence of two zinc binding proteins, approximately 660 and approximately 250 kDa respectively, in human seminal plasma and the prostatic origin of the approximately 660 kDa.

  13. Sequential Extraction Results in Improved Proteome Profiling of Medicinal Plant Pinellia ternata Tubers, Which Contain Large Amounts of High-Abundance Proteins

    PubMed Central

    An, SuFang; Gong, FangPing; Wang, Wei

    2012-01-01

    Pinellia ternata tuber is one of the well-known Chinese traditional medicines. In order to understand the pharmacological properties of tuber proteins, it is necessary to perform proteome analysis of P. ternata tubers. However, a few high-abundance proteins (HAPs), mainly mannose-binding lectin (agglutinin), exist in aggregates of various sizes in the tubers and seriously interfere with proteome profiling by two-dimensional electrophoresis (2-DE). Therefore, selective depletion of these HAPs is a prerequisite for enhanced proteome analysis of P. ternata tubers. Based on differential protein solubility, we developed a novel protocol involving two sequential extractions for depletion of some HAPs and prefractionation of tuber proteins prior to 2-DE. The first extraction using 10% acetic acid selectively extracted acid-soluble HAPs and the second extraction using the SDS-containing buffer extracted remaining acid-insoluble proteins. After application of the protocol, 2-DE profiles of P. ternata tuber proteins were greatly improved and more protein spots were detected, especially low-abundance proteins. Moreover, the subunit composition of P. ternata lectin was analyzed by electrophoresis. Native lectin consists of two hydrogen-bonded subunits (11 kDa and 25 kDa) and the 11 kDa subunit was a glycoprotein. Subsequently, major HAPs in the tubers were analyzed by mass spectrometry, with nine protein spots being identified as lectin isoforms. The methodology was easy to perform and required no specialized apparatus. It would be useful for proteome analysis of other tuber plants of Araceae. PMID:23185632

  14. Sequential extraction results in improved proteome profiling of medicinal plant Pinellia ternata tubers, which contain large amounts of high-abundance proteins.

    PubMed

    Wu, Xiaolin; Xiong, Erhui; An, Sufang; Gong, Fangping; Wang, Wei

    2012-01-01

    Pinellia ternata tuber is one of the well-known Chinese traditional medicines. In order to understand the pharmacological properties of tuber proteins, it is necessary to perform proteome analysis of P. ternata tubers. However, a few high-abundance proteins (HAPs), mainly mannose-binding lectin (agglutinin), exist in aggregates of various sizes in the tubers and seriously interfere with proteome profiling by two-dimensional electrophoresis (2-DE). Therefore, selective depletion of these HAPs is a prerequisite for enhanced proteome analysis of P. ternata tubers. Based on differential protein solubility, we developed a novel protocol involving two sequential extractions for depletion of some HAPs and prefractionation of tuber proteins prior to 2-DE. The first extraction using 10% acetic acid selectively extracted acid-soluble HAPs and the second extraction using the SDS-containing buffer extracted remaining acid-insoluble proteins. After application of the protocol, 2-DE profiles of P. ternata tuber proteins were greatly improved and more protein spots were detected, especially low-abundance proteins. Moreover, the subunit composition of P. ternata lectin was analyzed by electrophoresis. Native lectin consists of two hydrogen-bonded subunits (11 kDa and 25 kDa) and the 11 kDa subunit was a glycoprotein. Subsequently, major HAPs in the tubers were analyzed by mass spectrometry, with nine protein spots being identified as lectin isoforms. The methodology was easy to perform and required no specialized apparatus. It would be useful for proteome analysis of other tuber plants of Araceae.

  15. Characterization of a novel wheat endosperm protein belonging to the prolamin superfamily

    USDA-ARS?s Scientific Manuscript database

    Starch granule surface-associated proteins were separated by HPLC and identified by direct protein sequencing. Among the proteins identified was one that consisted of two polypeptide chains of 11 kDa and 19 kDa linked by disulfide bonds. Sequencing of tryptic peptides from each of the polypeptide ch...

  16. [Effects of noopept and cortexin on the behavior of matured rats treated with corticoliberin or 70-kDa heat shock proteins in early ontogeny].

    PubMed

    Shabanov, P D; Lebedev, A A; Stetsenko, V P; Lavrov, N V; Sablina, G V; Gudasheva, T A; Ostrovaskaia, R U

    2007-01-01

    Young Wistar rats aged 4 days were injected intraperitoneally with corticotropin releasing hormone (CRH), which is an agent activating the stress system, or 70-kDa heat shock proteins (HSP-70)--intracellular shaperons, possessing antistress properties. In grown adult rats aged 90-100 days, the effects of nootropic drugs noopept and cortexin (1 mg/kg, i.p.) were assessed. The activation of stress or antistress systems with CRH or HSP-70 significantly altered the drug action. The effects were different in males and females and depended on animal gender. The spectrum of pharmacological activity of noopept and cortexin changed: noopept demonstrated preferable psychoactivating and antiaggressive effects, whereas cortexin showed mild anxiolytic and antidepressant activity. It is suggested that the behavioral effects of nootropes depend on the conditions of the stress system formation in early ontogeny.

  17. Subcellular localization and expression pattern of the neurofibromatosis type 2 protein merlin/schwannomin.

    PubMed

    Schmucker, B; Ballhausen, W G; Kressel, M

    1997-01-01

    To elucidate the physiological function of the neurofibromatosis type 2 (NF2) tumor suppressor protein merlin/schwannomin, we studied the expression pattern and subcellular localization in human fibroblasts by Western blot analyses and immunofluorescence using a polyclonal antibody raised against the C-terminus of merlin. Three of the six merlin isoforms identified in this study (75 kDa, 58 kDa, 45 kDa) have been reported earlier and can be explained by alternative splicing. In addition, we detected higher molecular weight bands of about 110 kDa, 100 kDa and 84 kDa. Although the merlin bands of 100 kDa and 110 kDa may represent homo- or heterodimers, oligomerization due to formation of disulfide bonds was excluded. Furthermore, the isoforms of 84 kDa and 58 kDa were quantitatively extractable in Lubrol WX, indicating a localization in or close to the plasma membrane. The 45 kDa band, however, was not soluble in Lubrol WX compatible with a localization of this NF2 isoform in the endoplasmic reticulum. Applying confocal laser scanning microscopy, merlin was shown to be located in four subcellular compartments: (i) perinuclear in a compartment resembling endoplasmic reticulum, (ii) in ruffling membranes and at the leading edges, (iii) in filopodia, and (iv) at cell/substrate adhesion points. Codistribution of merlin and F-actin filaments was found in filopodia, ruffling membranes and at the insertion points of stress fibers at cell/substrate adhesion junctions as shown by phalloidin-rhodamine staining. Double immunofluorescence analyses of merlin and moesin revealed a colocalization in filopodia and ruffling membranes. The localization of merlin in the actin-rich cortical cytoskeleton corresponds to the ezrin-radixin-moesin family of proteins suggesting the NF2 protein to contribute to the regulation of cell growth by interaction with cytoskeleton-associated proteins.

  18. Transdermal Protein Delivery Using Choline and Geranate (CAGE) Deep Eutectic Solvent.

    PubMed

    Banerjee, Amrita; Ibsen, Kelly; Iwao, Yasunori; Zakrewsky, Michael; Mitragotri, Samir

    2017-08-01

    Transdermal delivery of peptides and other biological macromolecules is limited due to skin's inherent low permeability. Here, the authors report the use of a deep eutectic solvent, choline and geranate (CAGE), to enhance topical delivery of proteins such as bovine serum albumin (BSA, molecular weight: ≈66 kDa), ovalbumin (OVA, molecular weight: ≈45 kDa) and insulin (INS, molecular weight: 5.8 kDa). CAGE enhances permeation of BSA, OVA, and insulin into porcine skin ex vivo, penetrating deep into the epidermis and dermis. Studies using tritium-labeled BSA and fluorescein isothiocyanate labeled insulin show significantly enhanced delivery of proteins into and across porcine skin, penetrating the skin in a time-dependent manner. Fourier transform IR spectra of porcine stratum corneum (SC) samples before and after incubation in CAGE show a reduction in peak area attributed to SC lipid content, suggesting lipid extraction from the SC. Circular dichroism confirms that CAGE does not affect insulin's secondary conformation. In vivo studies in rats show that topical application of 10 U insulin dispersed in CAGE (25 U kg -1 insulin dose) leads to a highly significant 40% drop in blood glucose levels in 4 h that is relatively sustained for 12 h. Taken together, these studies demonstrate that CAGE is a promising vehicle for transdermal delivery of therapeutic proteins; specifically, as a noninvasive delivery alternative to injectable insulin for the treatment of diabetes. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Variation of expression defects in cell surface 190-kDa protein antigen of Streptococcus mutans.

    PubMed

    Lapirattanakul, Jinthana; Nomura, Ryota; Matsumoto-Nakano, Michiyo; Srisatjaluk, Ratchapin; Ooshima, Takashi; Nakano, Kazuhiko

    2015-05-01

    Streptococcus mutans, which consists of four serotypes, c, e, f, and k, possesses a 190-kDa cell surface protein antigen (PA) for initial tooth adhesion. We used Western blot analysis to determine PA expression in 750 S. mutans isolates from 150 subjects and found a significantly higher prevalence of the isolates with PA expression defects in serotypes f and k compared to serotypes c and e. Moreover, the defect patterns could be classified into three types; no PA expression on whole bacterial cells and in their supernatant samples (Type N1), PA expression mainly seen in supernatant samples (Type N2), and only low expression of PA in the samples of whole bacterial cells (Type W). The underlying reasons for the defects were mutations in the gene encoding PA as well as in the transcriptional processing of this gene for Type N1, defects in the sortase gene for Type N2, and low mRNA expression of PA for Type W. Since cellular hydrophobicity and phagocytosis susceptibility of the PA-defective isolates were significantly lower than those of the normal expression isolates, the potential implication of such defective isolates in systemic diseases involving bacteremia other than dental caries was suggested. Additionally, multilocus sequence typing was utilized to characterize S. mutans clones that represented a proportion of isolates with PA defects of 65-100%. Therefore, we described the molecular basis for variation defects in PA expression of S. mutans. Furthermore, we also emphasized the strong association between PA expression defects and serotypes f and k as well as the clonal relationships among these isolates. Copyright © 2015 Elsevier GmbH. All rights reserved.

  20. A dominant sulfhydryl-containing protein in the outer membrane of Neisseria gonorrhoeae.

    PubMed Central

    Norrod, E P; Browne, S L; Feldweg, A; Leonard, J

    1993-01-01

    By using a method that labels sulfhydryl-containing proteins in situ, we have detected a major outer membrane protein of Neisseria gonorrhoeae at 41 kDa. A protein of this molecular mass has not previously been shown to be a major outer membrane protein in gonococci. In addition, a minor protein rich in cysteinyl residues was detected at 31.5 kDa. Images PMID:8432710

  1. The fusion of Toxoplasma gondii SAG1 vaccine candidate to Leishmania infantum heat shock protein 83-kDa improves expression levels in tobacco chloroplasts.

    PubMed

    Albarracín, Romina M; Becher, Melina Laguía; Farran, Inmaculada; Sander, Valeria A; Corigliano, Mariana G; Yácono, María L; Pariani, Sebastián; López, Edwin Sánchez; Veramendi, Jon; Clemente, Marina

    2015-05-01

    Chloroplast transformation technology has emerged as an alternative platform offering many advantages over nuclear transformation. SAG1 is the main surface antigen of the intracellular parasite Toxoplasma gondii and a promising candidate to produce an anti-T. gondii vaccine. The aim of this study was to investigate the expression of SAG1 using chloroplast transformation technology in tobacco plants. In order to improve expression in transplastomic plants, we also expressed the 90-kDa heat shock protein of Leishmania infantum (LiHsp83) as a carrier for the SAG1 antigen. SAG1 protein accumulation in transplastomic plants was approximately 0.1-0.2 μg per gram of fresh weight (FW). Fusion of SAG1 to LiHsp83 significantly increased the level of SAG1 accumulation in tobacco chloroplasts (by up to 500-fold). We also evaluated the functionality of the chLiHsp83-SAG1. Three human seropositive samples reacted with SAG1 expressed in transplastomic chLiHsp83-SAG1 plants. Oral immunization with chLiHsp83-SAG1 elicited a significant reduction of the cyst burden that correlated with an increase of SAG1-specific antibodies. We propose the fusion of foreign proteins to LiHsp83 as a novel strategy to increase the expression level of the recombinant proteins using chloroplast transformation technology, thus addressing one of the current challenges for this approach in antigen protein production. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Erythrophagocytosis induces heat shock protein synthesis by human monocytes-macrophages.

    PubMed

    Clerget, M; Polla, B S

    1990-02-01

    Exposure of cells to elevated temperatures and other environmental stresses results in the expression of specific genes encoding the so-called heat shock proteins (HSPs). Since exogenous H2O2 induces in human monocytes the synthesis of HSPs, and previous induction of HSPs protects these cells from oxidative injury, we investigated whether HSP synthesis was also induced during generation of reactive oxygen species by the phagocyte itself during phagocytosis. As a model system, we analyzed the effects of erythrophagocytosis on protein synthesis by the human premonocytic line U937, in which phagocytosis is induced during differentiation with 1,25-dihydroxyvitamin D3. Exposure to whole erythrocytes, but not to erythrocyte ghosts, induced in the phagocytic cells only the synthesis of the 70- and 83- to 90-kDa HSPs and a 32-kDa oxidation-related stress protein identical by partial peptide mapping to heme oxygenase. The radioprotective aminothiol N-(2'-mercaptoethyl)-1,3-propanediamine (WR-1065), which can substitute for glutathione as hydrogen donor, prevented this induction. These results suggest that oxygen free radicals generated in the presence of hemoglobin-derived iron and consecutive glutathione depletion are involved in induction of stress protein synthesis during erythrophagocytosis. HSPs synthesized during phagocytosis may play a role in the phagocyte's defense mechanisms and in protective immunity.

  3. Purification and partial characterization of analogous 26-kDa rat submandibular and parotid gland integral membrane phosphoproteins that may have a role in exocytosis.

    PubMed

    Quissell, D O; Deisher, L M

    1992-04-01

    Rat submandibular and parotid gland exocytosis is primarily controlled by beta-adrenergic receptor stimulation. Although its precise role in the regulation of salivary gland exocytosis is not fully understood, protein phosphorylation, mediated by the activation of cAMP-dependent protein kinase, may be directly involved. Previous studies suggest that analogous 26-kDa integral membrane phosphoproteins may play a direct role in regulating exocytosis. Studies were here undertaken to purify and partially characterize both phosphoproteins. After endogenous phosphorylation with 32P, subcellular fraction and solubilization of the microsomal fraction in n-octyl beta-glucopyranoside, the 26-kDa integral membrane phosphoproteins were purified by high performance liquid chromatography (HPLC), followed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and electroelution of the proteins. Amino acid analysis indicated a significant number of serine amino acids: N-terminal sequence data demonstrated a high level of homology; and trypsin digestion followed by reversed-phase HPLC indicated the possibility of multiple phosphorylation sites.

  4. The location of a disease-associated polymorphism and genomic structure of the human 52-kDa Ro/SSA locus (SSA1)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tsugu, H.; Horowitz, R.; Gibson, N.

    1994-12-01

    Sera from approximately 30% of patients with systemic lupus erythematosus (SLE) contain high titers of autoantibodies that bind to the 52-kDa Ro/SSA protein. We previously detected polymorphisms in the 52-kDa Ro/SSA gene (SSA1) with restriction enzymes, one of which is strongly associated with the presence of SLE (P < 0.0005) in African Americans. A higher disease frequency and more severe forms of the disease are commonly noted among these female patients. To determine the location and nature of this polymorphism, we obtained two clones that span 8.5 kb of the 52-kDa Ro/SSA locus including its upstream regulatory region. Six exonsmore » were identified, and their nucleotide sequences plus adjacent noncoding regions were determined. No differences were found between these exons and the coding region of one of the reported cDNAs. The disease-associated polymorphic site suggested by a restriction enzyme map and confirmed by DNA amplification and nucleotide sequencing was present upstream of exon 1. This polymorphism may be a genetic marker for a disease-related variation in the coding region for the protein or in the upstream regulatory region of this gene. Although this RFLP is present in Japanese, it is not associated with lupus in this race. 41 refs., 4 figs., 2 tabs.« less

  5. Characterization of Bufo arenarum oocyte plasma membrane proteins that interact with sperm.

    PubMed

    Coux, Gabriela; Cabada, Marcelo O

    2006-04-28

    Sperm-oocyte plasma membrane interaction is an essential step in fertilization. In amphibians, the molecules involved have not been identified. Our aim was to detect and characterize oocyte molecules with binding affinity for sperm. We isolated plasma membranes free from vitelline envelope and yolk proteins from surface-biotinylated Bufo arenarum oocytes. Using binding assays we detected a biotinylated 100 kDa plasma membrane protein that consistently bound to sperm. Chromatographic studies confirmed the 100 kDa protein and detected two additional oocyte molecules of 30 and 70 kDa with affinity for sperm. Competition studies with an integrin-interacting peptide and cross-reaction with an anti-HSP70 antibody suggested that the 100 and 70 kDa proteins are members of the integrin family and HSP70, respectively. MS/MS analysis suggested extra candidates for a role in this step of fertilization. In conclusion, we provide evidence for the involvement of several proteins, including integrins and HSP70, in B. arenarum sperm-oocyte plasma membrane interactions.

  6. Effectivity of immunostimulant from Zoothamnium penaei protein membrane for decreasing the mortality rate of white shrimp (Litopenaeus vannamei) in traditional plus pond

    NASA Astrophysics Data System (ADS)

    Mahasri, G.; Kusdarwati, R.; Kismiyati; Rozi; Gustrifandi, H.

    2018-04-01

    The purpose of this research was to analys immunogenic membrane protein as immunostimulant development material to control the mortality of white shrimp in traditional plus pond. This research was designed to use explorative experiment and experimental laboratory methods which used completed random sampling design. Collected data was analyzed with analysis of variance for examination of survival rate (SR), total haemocyte count (THC) and differensial haemocyte Count (DHC). The research divided into 2 part of riset: (1) Identification, cultivation Zoothamnium penaei, analysed of membrane protein by SDS-PAGE, (2) Field test protein membran on Survival Rate level, immune response (THC and/or DHC level) and infestation of Zoothamnium penaei in traditional plus pond. The result showed that there were seven bands membrane protein of Zoothamnium penaei with molecular weight 38 kDa, 48 kDa, 67 kDa, 71 kDa, 77 kDa, 98 kDa dan 104 kDa by using SDS-PAGE. Immunogenicity tested decrease by using ELISA and western blotting there are only found three bands with molecular weight 38 kDa, 48 kDa dan 67 kDa. The membrane protein could increase the immun respons and decrease the mortality, by subsequenly, it could increase the survival rate from 17% until 68% and pressured the parasite infestation of white shrimp.

  7. Characterization of structural proteins of hirame rhabdovirus, HRV

    USGS Publications Warehouse

    Nishizawa, Toyohiko; Yoshimizu, Mamoru; Winton, James; Ahne, Winfried; Kimura, Takahisa

    1991-01-01

    Structural proteins of hirame rhabdovirus (HRV) were analyzed by SDS-polyacrylarnide gel electrophoresis, western blotting, 2-dimensional gel electrophoresis, and Triton X-100 treatment. Purified HRV virions were composed of: polymerase (L), glycoprotein (G), nucleoprotein (N), and 2 matrix proteins (M1 and M2). Based upon their relative mobilities, the estimated molecular weights of the proteins were: L, 156 KDa; G, 68 KDa; N, 46.4 KDa; M1, 26.4 KDa; and M2, 19.9 KDa. The electrophorehc pattern formed by the structural proteins of HRV was clearly different from that formed by pike fry rhabdovirus, spring viremia of carp virus, eel virus of America, and eel virus European X which belong to the Vesiculovirus genus; however, it resembled the pattern formed by structural proteins of viral hemorrhagic septicemia virus (VHSV) and infectious hematopoietic necrosis virus (IHNV) which are members of the Lyssavirus genus. Among HRV, IHNV, and VHSV, differences were observed in the relative mobilities of the G, N, M1, and M2 proteins. Western blot analysis revealed that the G. N, and M2 proteins of HRV shared antigenic determinants with IHNV and VHSV, but not with any of the 4 fish vesiculoviruses tested. Cross-reactions between the M1 proteins of HRV, IHNV, or VHSV were not detected in this assay. Two-dimensional gel electrophoresis was used to show that HRV differed from IHNV or VHSV in the isoelectric point (PI) of the M1 and M2 proteins. In this system, 2 forms of the M1 protein of HRV and IHNV were observed.These subspecies of M1 had the same relative mobility but different p1 values. Treatment of purified virions with 2% Triton X-100 in Tris buffer containing NaCl removed the G, M1, and M2 proteins of IHNV, but HRV virions were more stable under these conditions.

  8. A multicomponent complex is required for the AAUAAA-dependent cross-linking of a 64-kilodalton protein to polyadenylation substrates.

    PubMed Central

    Wilusz, J; Shenk, T; Takagaki, Y; Manley, J L

    1990-01-01

    A 64-kilodalton (kDa) polypeptide that is cross-linked by UV light specifically to polyadenylation substrate RNAs containing a functional AAUAAA element has been identified previously. Fractionated HeLa nuclear components that can be combined to regenerate efficient and accurate polyadenylation in vitro have now been screened for the presence of the 64-kDa protein. None of the individual components contained an activity which could generate the 64-kDa species upon UV cross-linking in the presence of substrate RNA. It was necessary to mix two components, cleavage stimulation factor and specificity factor, to reconstitute 64-kDa protein-RNA cross-linking. The addition of cleavage factors to this mixture very efficiently reconstituted the AAUAAA-specific 64-kDa protein-RNA interaction. The 64-kDa protein, therefore, is present in highly purified, reconstituted polyadenylation reactions. However, it is necessary to form a multicomponent complex to efficiently cross-link the protein to a substrate RNA. Images PMID:2304466

  9. The 46 kDa dimeric protein from Variovorax paradoxus shows faster methotrexate degrading activity in its nanoform compare to the native enzyme.

    PubMed

    Bayineni, Venkata Krishna; Venkatesh, Krishna; Sahu, Chandan Kumar; Kadeppagari, Ravi-Kumar

    2016-04-01

    Methotrexate degrading enzymes are required to overcome the toxicity of the methotrexate while treating the cancer. The enzyme from Variovorax paradoxus converts the methotrexate in to non toxic products. Methotrexate degrading enzyme from V. paradoxus is a dimeric protein with a molecular mass of 46 kDa and it acts on casein and gelatin. This enzyme is optimally active at pH 7.5 and 40°C and nanoparticles of this enzyme were prepared by desolvation-crosslinking method. Enzyme nanoparticles could degrade methotrexate faster than the native enzyme and they show lower Km compare to the native enzyme. Enzyme nanoparticles show better thermostability and they were stable for much longer time in the serum compare to the native enzyme. Enzyme nanoparticles show better functionality than the native enzyme while clearing the methotrexate added to the serum suggesting their advantage over the native enzyme for the therapeutic and biotechnological applications. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Differential expressed protein in developing stages of Nepenthes gracilis Korth. pitcher.

    PubMed

    Pinthong, Krit; Chaveerach, Arunrat; Tanee, Tawatchai; Sudmoon, Runglawan; Mokkamul, Piya

    2009-03-15

    Nepenthes gracilis Korth. is a member of carnivorous plants in family Nepenthaceae. The plants have beautiful and economically important pitchers. It is interesting to study the protein(s) correlated with the pitcher. Crude proteins were extracted from leaf, leaf with developing pitcher and developed pitcher of the same plant and analyzed by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE). Two protein bands with molecular weights of 42.7 and 38 kDa were obtained from young leaf and leaf with developing pitcher, respectively. The 42.7 kDa protein was identified as phosphoglycerate kinase (PGK) by Liquid Chromatography Mass Spectrometry (LC-MS/MS), but the 38 kDa band is an unknown protein. Both proteins were differentially expressed in each developing stage of the pitcher, thus may be powerful candidates play role in development pathway of leaf and pitcher.

  11. Identification of Group B Streptococcal Sip Protein, Which Elicits Cross-Protective Immunity

    PubMed Central

    Brodeur, Bernard R.; Boyer, Martine; Charlebois, Isabelle; Hamel, Josée; Couture, France; Rioux, Clément R.; Martin, Denis

    2000-01-01

    A protein of group B streptococci (GBS), named Sip for surface immunogenic protein, which is distinct from previously described surface proteins, was identified after immunological screening of a genomic library. Immunoblots using a Sip-specific monoclonal antibody indicated that a protein band with an approximate molecular mass of 53 kDa which did not vary in size was present in every GBS strain tested. Representatives of all nine GBS serotypes were included in the panel of strains. Cloning and sequencing of the sip gene revealed an open reading frame of 1,305 nucleotides coding for a polypeptide of 434 amino acid residues, with a calculated pI of 6.84 and molecular mass of 45.5 kDa. Comparison of the nucleotide sequences from six different strains confirmed with 98% identity that the sip gene is highly conserved among GBS isolates. N-terminal amino acid sequencing also indicated the presence of a 25-amino-acid signal peptide which is cleaved in the mature protein. More importantly, immunization with the recombinant Sip protein efficiently protected CD-1 mice against deadly challenges with six GBS strains of serotypes Ia/c, Ib, II/R, III, V, and VI. The data presented in this study suggest that this highly conserved protein induces cross-protective immunity against GBS infections and emphasize its potential as a universal vaccine candidate. PMID:10992461

  12. Plant 115-kDa actin-filament bundling protein, P-115-ABP, is a homologue of plant villin and is widely distributed in cells.

    PubMed

    Yokota, Etsuo; Vidali, Luis; Tominaga, Motoki; Tahara, Hiroshi; Orii, Hidefumi; Morizane, Yosuke; Hepler, Peter K; Shimmen, Teruo

    2003-10-01

    In many cases, actin filaments are arranged into bundles and serve as tracks for cytoplasmic streaming in plant cells. We have isolated an actin-filament bundling protein, which is composed of 115-kDa polypeptide (P-115-ABP), from the germinating pollen of lily, Lilium longiflorum [Nakayasu et al. (1998) BIOCHEM: Biophys. Res. Commun. 249: 61]. P-115-ABP shared similar antigenicity with a plant 135-kDa actin-filament bundling protein (P-135-ABP), a plant homologue of villin. A full-length cDNA clone (ABP115; accession no. AB097407) was isolated from an expression cDNA library of lily pollen by immuno-screening using antisera against P-115-ABP and P-135-ABP. The amino acid sequence of P-115-ABP deduced from this clone showed high homology with those of P-135-ABP and four villin isoforms of Arabidopsis thaliana (AtVLN1, AtVLN2, AtVLN3 and AtVLN4), especially AtVLN4, indicating that P-115-ABP can also be classified as a plant villin. The P-115-ABP isolated biochemically from the germinating lily pollen was able to arrange F-actin filaments with uniform polarity into bundles and this bundling activity was suppressed by Ca2+-calmodulin (CaM), similar to the actin-filament bundling properties of P-135-ABP. The P-115-ABP type of plant villin was widely distributed in plant cells, from algae to land plants. In root hair cells of Hydrocharis dubia, this type of plant villin was co-localized with actin-filament bundles in the transvacuolar strands and the sub-cortical regions. Microinjection of the antiserum against P-115-ABP into living root hair cells caused the disappearance of transvaculor strands and alteration of the route of cytoplasmic streaming. In internodal cells of Chara corallina in which the P-135-ABP type of plant villin is lacking, the P-115-ABP type showed co-localization with actin-filament cables anchored on the intracellular surface of chloroplasts. These results indicated that plant villins are widely distributed and involved in the organization of actin

  13. Molecular modeling and molecular dynamics simulations based structural analysis of the SG2NA protein variants.

    PubMed

    Soni, Sangeeta; Tyagi, Chetna; Grover, Abhinav; Goswami, Shyamal K

    2014-07-11

    SG2NA is a member of the striatin sub-family of WD-40 repeat proteins. Striatin family members have been associated with diverse physiological functions. SG2NA has also been shown to have roles in cell cycle progression, signal transduction etc. They have been known to interact with a number of proteins including Caveolin and Calmodulin and also propagate the formation of a multimeric protein unit called striatin-interacting phosphatase and kinase. As a pre-requisite for such interaction ability, these proteins are known to be unstable and primarily disordered in their arrangement. Earlier we had identified that it has multiple isoforms (namely 35, 78, 87 kDa based on its molecular weight) which are generated by alternative splicing. However, detailed structural information of SG2NA is still eluding the researchers. This study was aimed towards three-dimensional molecular modeling and characterization of SG2NA protein and its isoforms. One structure out of five was selected for each variant having the least value for C score. Out of these, m35 kDa with a C score value of -3.21 was the most poorly determined structure in comparison to m78 kDa and m87 kDa variants with C scores of -1.16 and -1.97 respectively. Further evaluation resulted in about 61.6% residues of m35 kDa, 76.6% residues of m78 kDa and 72.1% residues of m87 kDa falling in the favorable regions of Ramchandran Plot. Molecular dynamics simulations were also carried out to obtain biologically relevant structural models and compared with previous atomic coordinates. N-terminal region of all variants was found to be highly disordered. This study provides first-hand detailed information to understand the structural conformation of SG2NA protein variants (m35 kDa, m78 kDa and m87 kDa). The WD-40 repeat domain was found to constitute antiparallel strands of β-sheets arranged circularly. This study elucidates the crucial structural features of SG2NA proteins which are involved in various protein-protein

  14. Identification of two structurally related proteins involved in proteolytic processing of precursors targeted to the chloroplast.

    PubMed Central

    Oblong, J E; Lamppa, G K

    1992-01-01

    Two proteins of 145 and 143 kDa were identified in pea which co-purify with a chloroplast processing activity that cleaves the precursor for the major light-harvesting chlorophyll binding protein (preLHCP). Antiserum generated against the 145/143 kDa doublet recognizes only these two polypeptides in a chloroplast soluble extract. In immunodepletion experiments the antiserum removed the doublet, and there was a concomitant loss of cleavage of preLHCP as well as of precursors for the small subunit of Rubisco and the acyl carrier protein. The 145 and 143 kDa proteins co-eluted in parallel with the peak of processing activity during all fractionation procedures, but they were not detectable as a homo- or heterodimeric complex. The 145 and 143 kDa proteins were used separately to affinity purify immunoglobulins; each preparation recognized both polypeptides, indicating that they are antigenically related. Wheat chloroplasts contain a soluble species similar in size to the 145/143 kDa doublet. Images PMID:1385116

  15. [A case of IgA2-lambda type M-protein that IgA concentration differs from the values of M-protein by serum protein electrophoresis].

    PubMed

    Fukushima, M; Sugano, M; Ichikawa, T; Honda, T; Totsuka, M; Katsuyama, T; Fujita, K

    2001-07-01

    We report an IgA-lambda type M-protein in which the IgA concentration differed from the values of M-protein by serum protein electrophoresis found in a 53-year-old man with multiple myeloma. The M-protein value as determined by serum protein electrophoresis was 6,170 mg/dl. However, the serum IgA concentration was 3,052 mg/dl by turbidimetric immunoassay. Immuno-fixation electrophoresis using IgA subclass antisera revealed that this M-protein was the IgA2-lambda type. Western blotting analysis showed that the IgA2 molecules were composed of two approximately 68 kDa alpha 2 chains and two 28 kDa lambda chains. In addition the free lambda chain band was detected at the position of 28 kDa without 2-mercaptoethanol(2-ME) even though the patient IgA was purified. Since it is known that IgA2m(1) allotype easily release light chains from the IgA molecules in SDS-PAGE without 2-ME, we speculated that in this patient the IgA was the IgA2m(1) allotype. After peripheral blood stem cell transplantation(PBSCT), immunofixation electrophoresis of the patient serum revealed not only the bands of IgA2-lambda type M-protein, but also three bands of IgG1-kappa type M-protein in the gamma region.

  16. Protein Subcellular Localization with Gaussian Kernel Discriminant Analysis and Its Kernel Parameter Selection.

    PubMed

    Wang, Shunfang; Nie, Bing; Yue, Kun; Fei, Yu; Li, Wenjia; Xu, Dongshu

    2017-12-15

    Kernel discriminant analysis (KDA) is a dimension reduction and classification algorithm based on nonlinear kernel trick, which can be novelly used to treat high-dimensional and complex biological data before undergoing classification processes such as protein subcellular localization. Kernel parameters make a great impact on the performance of the KDA model. Specifically, for KDA with the popular Gaussian kernel, to select the scale parameter is still a challenging problem. Thus, this paper introduces the KDA method and proposes a new method for Gaussian kernel parameter selection depending on the fact that the differences between reconstruction errors of edge normal samples and those of interior normal samples should be maximized for certain suitable kernel parameters. Experiments with various standard data sets of protein subcellular localization show that the overall accuracy of protein classification prediction with KDA is much higher than that without KDA. Meanwhile, the kernel parameter of KDA has a great impact on the efficiency, and the proposed method can produce an optimum parameter, which makes the new algorithm not only perform as effectively as the traditional ones, but also reduce the computational time and thus improve efficiency.

  17. Identification and molecular characterization of 48 kDa calcium binding protein as calreticulin from finger millet (Eleusine coracana) using peptide mass fingerprinting and transcript profiling.

    PubMed

    Singh, Manoj; Metwal, Mamta; Kumar, Vandana A; Kumar, Anil

    2016-01-30

    Attempts were made to identify and characterize the calcium binding proteins (CaBPs) in grain filling stages of finger millet using proteomics, bioinformatics and molecular approaches. A distinctly observed blue color band of 48 kDa stained by Stains-all was eluted and analyzed as calreticulin (CRT) using nano liquid chromatography-tandem mass spectrometry (nano LC-MS). Based on the top hits of peptide mass fingerprinting results, conserved primers were designed for isolation of the CRT gene from finger millet using calreticulin sequences of different cereals. The deduced nucleotide sequence analysis of 600 bp amplicon showed up to 91% similarity with CRT gene(s) of rice and other plant species and designated as EcCRT1. Transcript profiling of EcCRT1 showed different levels of relative expression at different stages of developing spikes. The higher expression of EcCRT1 transcripts and protein were observed in later stages of developing spikes which might be due to greater translational synthesis of EcCRT1 protein during seed maturation in finger millet. Preferentially higher synthesis of this CaBP during later stages of grain filling may be responsible for the sequestration of calcium in endoplasmic reticulum of finger millet grains. © 2015 Society of Chemical Industry.

  18. Influence of Culture Conditions on Expression of the 40-Kilodalton Porin Protein of Vibrio anguillarum Serotype O2

    PubMed Central

    Davey, Michelle L.; Hancock, Robert E. W.; Mutharia, Lucy M.

    1998-01-01

    Vibrio anguillarum serotype O2 strains express a 40-kDa outer membrane porin protein. Immunoblot analysis revealed that antigenic determinants of the V. anguillarum O2 40-kDa porin were conserved within bacterial species of the genus Vibrio. The relative amounts of the V. anguillarum O2 40-kDa porin were enhanced by growth of V. anguillarum O2 in CM9 medium containing 5 to 10% sucrose or 0.1 to 0.5 M NaCl. In contrast, the levels of the porin were significantly reduced when cells were grown at 37°C, and a novel 60-kDa protein was also observed. However, the osmolarity or ionic concentration of the growth medium did not influence expression of the 60-kDa protein. Growth in medium containing greater than 0.6 mM EDTA reduced production of the V. anguillarum O2 40-kDa porin and enhanced levels of a novel 19-kDa protein. Thus, expression of the V. anguillarum O2 40-kDa porin was osmoregulated and possibly coregulated by temperature. The N-terminal amino acid sequence of the V. anguillarum O2 40-kDa protein and the effect of environmental factors on the cellular levels of the porin suggested that the V. anguillarum O2 40-kDa porin was functionally similar to the OmpC porin of Escherichia coli. However, pore conductance assays revealed that the V. anguillarum O2 40-kDa porin was a general diffusion porin with a pore size in the range of that of the OmpF porin of E. coli. PMID:9435071

  19. Antitumor activity against murine lymphoma L5178Y model of proteins from cacao (Theobroma cacao L.) seeds in relation with in vitro antioxidant activity.

    PubMed

    Preza, Ana M; Jaramillo, María E; Puebla, Ana M; Mateos, Juan C; Hernández, Rodolfo; Lugo, Eugenia

    2010-10-20

    Recently, proteins and peptides have become an added value to foodstuffs due to new knowledge about its structural analyses as related to antioxidant and anticancer activity. Our goal was to evaluate if protein fractions from cacao seeds show antitumor activity on lymphoma murine L5178Y model. The antioxidant activity of these fractions was also evaluated with the aim of finding a correlation with the antitumor activity. Differential extraction of proteins from unfermented and semi-fermented-dry cacao seeds was performed and characterized by SDS-PAGE and FPLC size-exclusion chromatography. Antitumor activity was evaluated against murine lymphoma L5178Y in BALB/c mice (6 × 104 cells i.p.), with a treatment oral dose of 25 mg/kg/day of each protein fraction, over a period of 15 days. Antioxidant activity was evaluated by the ABTS+ and ORAC-FL assays. Albumin, globulin and glutelin fractions from both cacao seed type were obtained by differential solubility extraction. Glutelins were the predominant fraction. In the albumin fraction, polypeptides of 42.3 and 8.5 kDa were found in native conditions, presumably in the form of two peptide chains of 21.5 kDa each one. The globulin fraction presented polypeptides of 86 and 57 kDa in unfermented cacao seed that produced the specific-cacao aroma precursors, and after fermentation the polypeptides were of 45 and 39 kDa. The glutelin fraction presented proteins >200 kDa and globulins components <100 KDa in lesser proportion. Regarding the semifermented-dry cacao seed, it was observed that the albumin fraction showed antitumoral activity, since it caused significant decreases (p < 0.05) in the ascetic fluid volume and packed cell volume, inhibiting cell growth in 59.98 ± 13.6% at 60% of the population; while the greatest antioxidant capacity due to free radical scavenging capacity was showed by the albumin and glutelin fraction in both methods assayed. This study is the first report on the biological activity of semifermented

  20. Indonesian honey protein isolation Apis dorsata dorsata and Tetragonula sp. as antibacterial and antioxidant agent

    NASA Astrophysics Data System (ADS)

    Sahlan, Muhamad; Damayanti, Vina; Azizah, Nurul; Hakamada, Kazuaki; Yohda, Masafumi; Hermansyah, Heri; Wijanarko, Anondho; Rohmatin, Etin

    2018-02-01

    Honey is a natural product that has many properties and been widely used for many theurapeutic purposes. Research on honey has been very rapid but not yet for Indonesia. Like local Indonesian honey Apis dorsata dorsata and Tetragonula sp. which has been widely consumed by the public but not yet known for certain efficacy of each content. The function of honey as antibacterial and antioxidant has not been specifically explained by the components contained in honey. Protein is one of the content of honey that turned out to have activity as an antibacterial and antioxidant in certain types of honey because of it antimicrobial peptide. Testing of honey activity as antibacterial and antioxidant through several stages including isolation, SDS-PAGE analysis, Bradford test, antibacterial activity test with well diffusion method and antioxidant activity test by DPPH method. Bacteria used were gram-positive bacteria Staphylococcus aureus and gram negative Escherichia coli. After some experiment finally got protein isolation method that is in the form of further concentration using Millipore membrane for honey Tetragonula sp. and membrane filtration dot blot for honey Apis dorsata dorsata. The Bradford assay showed that Apis dorsata dorsata honey contains protein <5 µg / ml, while honey Tetragonula sp. has a protein content of 97 µg / ml. The characteristic profile of molecular weight of the protein showed honey Tetragonula sp. has 3 protein bands composed of 52, 96 - 61,9 kDa, 63,35 - 65,92 kDa and 86,16 - 91,4 kDa, whereas Apis dorsata dorsata honey has 5 protein bands consisting of 45,2 - 46,6 kDa, 50,2 - 50,9 kDa, 62,5 - 62,9 kDa, 73,1 - 73,9 kDa, 83,9 - 86,9 kDa. Isolate honey protein Apis dorsata dorsata has no antioxidant and antibacterial activity (Staphylococcus aureus and Escherichia coli), whereas honey protein isolates Tetragonula sp. has antibacterial activity against Escherichia coli.

  1. Definition of IgG- and albumin-binding regions of streptococcal protein G.

    PubMed

    Akerström, B; Nielsen, E; Björck, L

    1987-10-05

    Protein G, the immunoglobin G-binding surface protein of group C and G streptococci, also binds serum albumin. The albumin-binding site on protein G is distinct from the immunoglobulin G-binding site. By mild acid hydrolysis of the papain-liberated protein G fragment (35 kDa), a 28-kDa fragment was produced which retained full immunoglobulin G-binding activity (determined by Scatchard plotting) but had lost all albumin-binding capacity. A protein G (65 kDa), isolated after cloning and expression of the protein G gene in Escherichia coli, had comparable affinity to immunoglobulin G (5-10 X 10(10)M-1), but much higher affinity to albumin than the 35- and 28-kDa protein G fragments (31, 2.6, and 0 X 10(9)M-1, respectively). The amino-terminal amino acid sequences of the 65-, 35-, and 28-kDa fragments allowed us to exactly locate the three fragments in an overall sequence map of protein G, based on the partial gene sequences published by Guss et al. (Guss, B., Eliasson, M., Olsson, A., Uhlen, M., Frej, A.-K., Jörnvall, H., Flock, J.-I., and Lindberg, M. (1986) EMBO J. 5, 1567-1575) and Fahnestock et al. (Fahnestock, S. R., Alexander, P., Nagle, J., and Filpula, D. (1986) J. Bacteriol. 167, 870-880). In this map could then be deduced the location of three homologous albumin-binding regions and three homologous immunoglobulin G-binding regions.

  2. Proteomic analysis of seed storage proteins in wild rice species of the Oryza genus.

    PubMed

    Jiang, Chunmiao; Cheng, Zaiquan; Zhang, Cheng; Yu, Tengqiong; Zhong, Qiaofang; Shen, J Qingxi; Huang, Xingqi

    2014-01-01

    The total protein contents of rice seeds are significantly higher in the three wild rice species (Oryza rufipogon Grill., Oryza officinalis Wall. and Oryza meyeriana Baill.) than in the cultivated rice (Oryza sativa L.). However, there is still no report regarding a systematic proteomic analysis of seed proteins in the wild rice species. Also, the relationship between the contents of seed total proteins and rice nutritional quality has not been thoroughly investigated. The total seed protein contents, especially the glutelin contents, of the three wild rice species were higher than those of the two cultivated rice materials. Based on the protein banding patterns of SDS-PAGE, O. rufipogon was similar to the two cultivated rice materials, followed by O. officinalis, while O. meyeriana exhibited notable differences. Interestingly, O. meyeriana had high contents of glutelin and low contents of prolamine, and lacked 26 kDa globulin band and appeared a new 28 kDa protein band. However, for O. officinali a 16 kDa protein band was absent and a row of unique 32 kDa proteins appeared. In addition, we found that 13 kDa prolamine band disappeared while special 14 kDa and 12 kDa protein bands were present in O. officinalis. Two-dimensional gel electrophoresis (2-DE) analysis revealed remarkable differences in protein profiles of the wild rice species and the two cultivated rice materials. Also, the numbers of detected protein spots of the three wild rice species were significantly higher than those of two cultivated rice. A total of 35 differential protein spots were found for glutelin acidic subunits, glutelin precursors and glutelin basic subunits in wild rice species. Among those, 18 protein spots were specific and 17 major spots were elevated. Six differential protein spots for glutelin acidic subunits were identified, including a glutelin type-A 2 precursor and five hypothetical proteins. This was the first report on proteomic analysis of the three wild rice species

  3. An autoclave treatment reduces the solubility and antigenicity of an allergenic protein found in buckwheat flour.

    PubMed

    Tomotake, Hiroyuki; Yamazaki, Rikio; Yamato, Masayuki

    2012-06-01

    The effects of an autoclave treatment of buckwheat flour on a 24-kDa allergenic protein were investigated by measuring reduction in solubility and antibody binding. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that the intensity of the major bands, including that of the 24-kDa allergen, was reduced by the autoclave treatment. The protein solubility in buckwheat flour was variably decreased by the autoclave treatment. Enzyme-linked immunosorbent assay analysis using a monoclonal antibody specific for buckwheat 24-kDa protein showed that the reactivity of protein extracts (10 μg/ml) from buckwheat flour was lowered by the autoclave treatment. The autoclave treatment may reduce the major allergen content of buckwheat. Future studies will determine if autoclaving treatments affect the allergenicity of the 24-kDa buckwheat protein.

  4. SNAP-25 requirement for dendritic growth of hippocampal neurons.

    PubMed

    Grosse, G; Grosse, J; Tapp, R; Kuchinke, J; Gorsleben, M; Fetter, I; Höhne-Zell, B; Gratzl, M; Bergmann, M

    1999-06-01

    Structure and dimension of the dendritic arbor are important determinants of information processing by the nerve cell, but mechanisms and molecules involved in dendritic growth are essentially unknown. We investigated early mechanisms of dendritic growth using mouse fetal hippocampal neurons in primary culture, which form processes during the first week in vitro. We detected a key component of regulated exocytosis, SNAP-25 (synaptosomal associated protein of 25 kDa), in axons and axonal terminals as well as in dendrites identified by the occurrence of the dendritic markers transferrin receptor and MAP2. Selective inactivation of SNAP-25 by botulinum neurotoxin A (BoNTA) resulted in inhibition of axonal growth and of vesicle recycling in axonal terminals. In addition, dendritic growth of hippocampal pyramidal and granule neurons was significantly inhibited by BoNTA. In contrast, cleavage of synaptobrevin by tetanus toxin had an effect on neither axonal nor dendritic growth. Our observations indicate that SNAP-25, but not synaptobrevin, is involved in constitutive axonal growth and dendrite formation by hippocampal neurons.

  5. Substitutions mimicking deimination and phosphorylation of 18.5-kDa myelin basic protein exert local structural effects that subtly influence its global folding.

    PubMed

    Vassall, Kenrick A; Bamm, Vladimir V; Jenkins, Andrew D; Velte, Caroline J; Kattnig, Daniel R; Boggs, Joan M; Hinderberger, Dariush; Harauz, George

    2016-06-01

    Intrinsically-disordered proteins (IDPs) present a complex interplay of conformational variability and multifunctionality, modulated by environment and post-translational modifications. The 18.5-kDa myelin basic protein (MBP) is essential to the formation of the myelin sheath of the central nervous system and is exemplary in this regard. We have recently demonstrated that the unmodified MBP-C1 component undergoes co-operative global conformational changes in increasing concentrations of trifluoroethanol, emulating the decreasing dielectric environment that the protein encounters upon adsorption to the oligodendrocyte membrane [K.A. Vassall et al., Journal of Molecular Biology, 427, 1977-1992, 2015]. Here, we extended this study to the pseudo-deiminated MBP-C8 charge component, one found in greater proportion in developing myelin and in multiple sclerosis. A similar tri-conformational distribution as for MBP-C1 was observed with slight differences in Gibbs free energy. A more dramatic difference was observed by cathepsin D digestion of the protein in both aqueous and membrane environments, which showed significantly greater accessibility of the F42-F43 cut site of MBP-C8, indicative of a global conformational change. In contrast, this modification caused little change in the protein's density of packing on myelin-mimetic membranes as ascertained by double electron-electron resonance spectroscopy [D.R. Kattnig et al., Biochimica et Biophysica Acta (Biomembranes), 1818, 2636-2647, 2012], or in its affinity for Ca(2+)-CaM. Site-specific threonyl pseudo-phosphorylation at residues T92 and/or T95 did not appreciably affect any of the thermodynamic mechanisms of conformational transitions, susceptibility to cathepsin D, or affinity for Ca(2+)-CaM, despite previously having been shown to affect local structure and disposition on the membrane surface. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Purification and characterization of protein PC, a component of glycine reductase from Eubacterium acidaminophilum.

    PubMed

    Schräder, T; Andreesen, J R

    1992-05-15

    Protein PC of the glycine reductase from Eubacterium acidaminophilum was purified to homogeneity by chromatography on phenyl-Sepharose and Sepharose S. The apparent molecular mass of the native protein, which showed an associating/dissociating behaviour, was about 420 kDa. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis of protein PC revealed two protein bands corresponding to 48 and 57 kDa, indicating an alpha 4 beta 4 composition. The smaller subunit was identified as an acetyl-group-transferring protein, the 57-kDa protein was hydrophobic. N-terminal amino acid sequences were determined for both subunits. Antibodies raised against the 48-kDa subunit showed cross-reactions with extracts of E. acidaminophilum grown on different substrates and with extracts from other glycine-utilizing anaerobic bacteria such as Clostridium purinolyticum, C. sticklandii, and C. sporogenes. The respective protein from the former two organisms corresponded in molecular mass. When protein PA was chemically carboxymethylated by iodo[2-14C]acetate and incubated with protein PC, acetyl phosphate was a reaction product, thus establishing it as the product of the glycine reductase reaction by using homogeneous preparations of these two proteins from E. acidaminophilum.

  7. Intracellular transport and processing of the Marburg virus surface protein in vertebrate and insect cells.

    PubMed

    Becker, S; Klenk, H D; Mühlberger, E

    1996-11-01

    The surface protein (GP) of Marburg virus (MBG) is synthesized as a 90-kDa precursor protein which is cotranslationally modified by the addition of high-mannose sugars (140 kDa). This step is followed by the conversion of the N-linked sugars to endoglycosidase H (endo H)-resistant species and the addition of O-linked oliosaccharides leading to a mature protein of 170-200 kDa approximately 30 min after pulse labelling. The mature form of GP is efficiently transported to the plasma membrane. GP synthesized using the T7 polymerase-driven vaccinia virus expression system was transported with essentially the same kinetics as the authentic GP. However, the protein that is shown to appear 30 min after pulse labeling at the plasma membrane was slighly smaller (160 kDa) than GP incorporated into the virions (170 kDa). Using a recombinant baculovirus, GP was expressed at high levels in insect cells. Three different species could be identified: a 90-kDa unglycosylated GP localized in the cytoplasm and two 140-kDa glycosylated proteins. Characterization of the glycosylated GPs revealed that processing of the oligosaccharides of GP was less efficient in insect cells than in mammalian cells. The majority of GP remained endo H sensitive containing high-mannose type N-linked glycans, whereas only a small fraction became endo H resistant carrying processed N-glycans and O-glycans. Tunicamycin treatment of the GP-expressing cells demonstrated that N-glycosylation is essential for the transport of the MBG surface protein.

  8. A facile approach to the isolation of proteins in Ferula asafoetida and their enzyme stabilizing, anti-microbial and anti-oxidant activity.

    PubMed

    Chandran, Sanjana; Sakthivel, Meenakumari; Thirumavalavan, Munusamy; Thota, Jagadeshwar Reddy; Mariappanadar, Vairamani; Raman, Pachaiappan

    2017-09-01

    The objective of the present study was to identify the proteome pattern, isolate and study the functions of selective proteins from Ferula asafoetida root exudate using chromatographic techniques. The root exudate proteins were fractionated using ion-exchange and gel filtration chromatography. A range of bioactive protein fractions were then separated in sufficient quantity which is the focus of this study. Based on studies, here we report three main proteins with molecular weights 14kDa, 27kDa, and 39kDa. The biological and pharmacological activities of both purified and unpurified proteins obtained were extensively studied to understand their significance. The study revelaed that 27kDa protein interestingly stabilized trypsin activity in 24h of time and retained about 64% of the enzyme activity. Analyses confirmed 40°C and pH 8.0 are the optimum temperature and pH respectively. The 39kDa protein remarkably increased the activity of chymotrypsin and the 14kDa protein showed anti-bacterial activity against Pseudomonas aeruginosa. Invariably all of the three purified proteins showed enhanced anti-oxidant activity. In conclusion, results here obtained suggested that the primary metabolites (proteins) in asafoetida are mainly responsible for its versatile biological and pharmacological activities. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Molecular characterization of domestic and exotic potato virus S isolates and a global analysis of genomic sequences.

    PubMed

    Lin, Y-H; Abad, J A; Maroon-Lango, C J; Perry, K L; Pappu, H R

    2014-08-01

    Five potato virus S (PVS) isolates from the USA and three isolates from Chile were characterized based on biological and molecular properties to delineate these PVS isolates into either ordinary (PVS(O)) or Andean (PVS(A)) strains. Five isolates - 41956, Cosimar, Galaxy, ND2492-2R, and Q1 - were considered ordinary strains, as they induced local lesions on the inoculated leaves of Chenopodium quinoa, whereas the remaining three (FL206-1D, Q3, and Q5) failed to induce symptoms. Considerable variability of symptom expression and severity was observed among these isolates when tested on additional indicator plants and potato cv. Defender. Additionally, all eight isolates were characterized by determining the nucleotide sequences of their coat protein (CP) genes. Based on their biological and genetic properties, the 41956, Cosimar, Galaxy, ND2492-2R, and Q1 isolates were identified as PVS(O). PVS-FL206-1D and the two Chilean isolates (PVS-Q3 and PVS-Q5) could not be identified based on phenotype alone; however, based on sequence comparisons, PVS-FL206-1D was identified as PVS(O), while Q3 and Q5 clustered with known PVS(A) strains. C. quinoa may not be a reliable indicator for distinguishing PVS strains. Sequences of the CP gene should be used as an additional criterion for delineating PVS strains. A global genetic analysis of known PVS sequences from GenBank was carried out to investigate nucleotide substitution, population selection, and genetic recombination and to assess the genetic diversity and evolution of PVS. A higher degree of nucleotide diversity (π value) of the CP gene compared to that of the 11K gene suggested greater variation in the CP gene. When comparing PVS(A) and PVS(O) strains, a higher π value was found for PVS(A). Statistical tests of the neutrality hypothesis indicated a negative selection pressure on both the CP and 11K proteins of PVS(O), whereas a balancing selection pressure was found on PVS(A).

  10. Formation of Hirano Bodies Induced by Expression of an Actin Cross-Linking Protein with a Gain-of-Function Mutation

    PubMed Central

    Maselli, Andrew; Furukawa, Ruth; Thomson, Susanne A. M.; Davis, Richard C.; Fechheimer, Marcus

    2003-01-01

    Hirano bodies are paracrystalline actin filament-containing structures reported to be associated with a variety of neurodegenerative diseases. However, the biological function of Hirano bodies remains poorly understood, since nearly all prior studies of these structures were done with postmortem samples of tissue. In the present study, we generated a full-length form of a Dictyostelium 34-kDa actin cross-linking protein with point mutations in the first putative EF hand, termed 34-kDa ΔEF1. The 34-kDa ΔEF1 protein binds calcium normally but has activated actin binding that is unregulated by calcium. The expression of the 34-kDa ΔEF1 protein in Dictyostelium induces the formation of Hirano bodies, as assessed by both fluorescence microscopy and transmission electron microscopy. Dictyostelium cells bearing Hirano bodies grow normally, indicating that Hirano bodies are not associated with cell death and are not deleterious to cell growth. Moreover, the expression of the 34-kDa ΔEF1 protein rescues the phenotypes of cells lacking the 34-kDa protein and cells lacking both the 34-kDa protein and α-actinin. Finally, the expression of the 34-kDa ΔEF1 protein also initiates the formation of Hirano bodies in cultured mouse fibroblasts. These results show that the failure to regulate the activity and/or affinity of an actin cross-linking protein can provide a signal for the formation of Hirano bodies. More generally, the formation of Hirano bodies is a cellular response to or a consequence of aberrant function of the actin cytoskeleton. PMID:12912897

  11. Studying the highly bent spectra of FR II-type radio galaxies with the KDA EXT model

    NASA Astrophysics Data System (ADS)

    Kuligowska, Elżbieta

    2018-04-01

    Context. The Kaiser, Dennett-Thorpe & Alexander (KDA, 1997, MNRAS, 292, 723) EXT model, that is, the extension of the KDA model of Fanaroff & Riley (FR) II-type source evolution, is applied and confronted with the observational data for selected FR II-type radio sources with significantly aged radio spectra. Aim. A sample of FR II-type radio galaxies with radio spectra strongly bent at their highest frequencies is used for testing the usefulness of the KDA EXT model. Methods: The dynamical evolution of FR II-type sources predicted with the KDA EXT model is briefly presented and discussed. The results are then compared to the ones obtained with the classical KDA approach, assuming the source's continuous injection and self-similarity. Results: The results and corresponding diagrams obtained for the eight sample sources indicate that the KDA EXT model predicts the observed radio spectra significantly better than the best spectral fit provided by the original KDA model.

  12. Association of Guide RNA Binding Protein gBP21 with Active RNA Editing Complexes in Trypanosoma brucei

    PubMed Central

    Allen, Thomas E.; Heidmann, Stefan; Reed, RoseMary; Myler, Peter J.; Göringer, H. Ulrich; Stuart, Kenneth D.

    1998-01-01

    RNA editing in Trypanosoma brucei mitochondria produces mature mRNAs by a series of enzyme-catalyzed reactions that specifically insert or delete uridylates in association with a macromolecular complex. Using a mitochondrial fraction enriched for in vitro RNA editing activity, we produced several monoclonal antibodies that are specific for a 21-kDa guide RNA (gRNA) binding protein initially identified by UV cross-linking. Immunofluorescence studies localize the protein to the mitochondrion, with a preference for the kinetoplast. The antibodies cause a supershift of previously identified gRNA-specific ribonucleoprotein complexes and immunoprecipitate in vitro RNA editing activities that insert and delete uridylates. The immunoprecipitated material also contains gRNA-specific endoribonuclease, terminal uridylyltransferase, and RNA ligase activities as well as gRNA and both edited and unedited mRNA. The immunoprecipitate contains numerous proteins, of which the 21-kDa protein, a 90-kDa protein, and novel 55- and 16-kDa proteins can be UV cross-linked to gRNA. These studies indicate that the 21-kDa protein associates with the ribonucleoprotein complex (or complexes) that catalyze RNA editing. PMID:9742118

  13. Pseudomonas oleovorans Strain KBPF-004 Culture Supernatants Reduced Seed Transmission of Cucumber green mottle mosaic virus and Pepper mild mottle virus, and Remodeled Aggregation of 126 kDa and Subcellular Localization of Movement Protein of Pepper mild mottle virus

    PubMed Central

    Kim, Nam-Gyu; Seo, Eun-Young; Han, Sang-Hyuk; Gong, Jun-Su; Park, Cheol-Nam; Park, Ho-Seop; Domier, Leslie L; Hammond, John; Lim, Hyoun-Sub

    2017-01-01

    Efforts to control viral diseases in crop production include several types of physical or chemical treatments; antiviral extracts of a number of plants have also been examined to inhibit plant viral infection. However, treatments utilizing naturally selected microorganisms with activity against plant viruses are poorly documented. Here we report isolation of a soil inhabiting bacterium, Pseudomonas oleovorans strain KBPF-004 (developmental code KNF2016) which showed antiviral activity against mechanical transmission of tobamoviruses. Antiviral activity was also evaluated in seed transmission of two tobamoviruses, Pepper mild mottle virus (PMMoV) and Cucumber green mottle mosaic virus (CGMMV), by treatment of seed collected from infected pepper and watermelon, respectively. Pepper and watermelon seeds were treated with culture supernatant of P. oleovorans strain KBPF-004 or control strain ATCC 8062 before planting. Seeds germinated after treatment with water or ATCC 8062 yielded about 60% CGMMV or PMMoV positive plants, whereas < 20% of KBPF-004-treated seeds were virus-infected, a significantly reduced seed transmission rate. Furthermore, supernatant of P. oleovorans strain KBPF-004 remodeled aggregation of PMMoV 126 kDa protein and subcellular localization of movement protein in Nicotiana benthamiana, diminishing aggregation of the 126 kDa protein and essentially abolishing association of the movement protein with the microtubule network. In leaves agroinfiltrated with constructs expressing the coat protein (CP) of either PMMoV or CGMMV, less full-size CP was detected in the presence of supernatant of P. oleovorans strain KBPF-004. These changes may contribute to the antiviral effects of P. oleovorans strain KBPF-004. PMID:28811756

  14. Heat shock proteins on the human sperm surface.

    PubMed

    Naaby-Hansen, Soren; Herr, John C

    2010-01-01

    The sperm plasma membrane is known to be critical to fertilization and to be highly regionalized into domains of head, mid- and principal pieces. However, the molecular composition of the sperm plasma membrane and its alterations during genital tract passage, capacitation and the acrosome reaction remains to be fully dissected. A two-dimensional gel-based proteomic study previously identified 98 human sperm proteins which were accessible for surface labelling with both biotin and radioiodine. In this report twelve dually labelled protein spots were excised from stained gels or PDVF membranes and analysed by mass spectrometry (MS) and Edman degradation. Seven members from four different heat shock protein (HSP) families were identified including HYOU1 (ORP150), HSPC1 (HSP86), HSPA5 (Bip), HSPD1 (HSP60), and several isoforms of the two testis-specific HSP70 chaperones HSPA2 and HSPA1L. An antiserum raised against the testis-specific HSPA2 chaperone reacted with three 65kDa HSPA2 isoforms and three high molecular weight surface proteins (78-79kDa, 84kDa and 90-93kDa). These proteins, together with seven 65kDa HSP70 forms, reacted with human anti-sperm IgG antibodies that blocked in vitro fertilization in humans. Three of these surface biotinylated human sperm antigens were immunoprecipitated with a rabbit antiserum raised against a linear peptide epitope in Chlamydia trachomatis HSP70. The results indicate diverse HSP chaperones are accessible for surface labelling on human sperm. Some of these share epitopes with C. trachomatis HSP70, suggesting an association between genital tract infection, immunity to HSP70 and reproductive failure. 2009 Elsevier Ireland Ltd. All rights reserved.

  15. The oxygen evolving enhancer protein 1 (OEE) of photosystem II in green algae exhibits thioredoxin activity.

    PubMed

    Heide, Heinrich; Kalisz, Henryk M; Follmann, Hartmut

    2004-02-01

    A thioredoxin-like chloroplast protein of the fructosebisphosphatase-stimulating f-type, but with an unusually high molecular mass of 28 kDa has previously been identified and purified to homogeneity in a fractionation scheme for resolution of the acid- and heat-stable, regular-size (12kDa) thioredoxins of the unicellular green algae, Scenedesmus obliquus. An apparently analogous protein of 26 kDa was described in a cyanobacterium, Anabaena sp., but no such large thioredoxin species f exists in the thioredoxin profiles of higher plants. The structure of the 28 kDa protein, which had been envisaged to represent a precursor, or fusion product of the two more specialized, common chloroplast thioredoxins f and m has now been determined by amino acid sequencing. Although it exhibits virtually all the properties and enzyme-modulating activities of a thioredoxin proper this algal protein, surprisingly, does not belong to the thioredoxin family of small redox proteins but is identical with OEE (oxygen evolving enhancer) protein 1, an auxiliary component of the photosystem II manganese cluster. Extracts of Chlorella vulgaris and Chlamydomonas reinhardtii also contain heat-stable protein fractions of 23-26 kDa capable of specifically stimulating chloroplast fructosebisphosphatase in vitro. In contrast, OEE protein 1 from spinach is not able to modulate FbPase or NADP malate dehydrogenase from spinach chloroplasts. A dual function of the OEE protein in algal photosynthesis is envisaged.

  16. Purification and characterization of a membrane-associated 3,3',5-triiodo-L-thyronine binding protein from a human carcinoma cell line.

    PubMed Central

    Cheng, S Y; Hasumura, S; Willingham, M C; Pastan, I

    1986-01-01

    A membrane-associated binding protein for 3,3',5-triiodo-L-thyronine (T3) was purified to apparent homogeneity from A431 human epidermoid carcinoma cells. A431 cells were specifically labeled with the N-bromoacetyl derivative of T3 labeled with 125I at the 3' position (BrAc[125I]T3) and were extracted with 3-[3-(cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), a zwitterionic detergent. The solubilized BrAc[125I]T3-labeled protein was successively purified by chromatography on Sephadex G-200 and QAE-Sephadex followed by NaDod-SO4/PAGE. Approximately 0.2 mg of purified protein was obtained from 2.5 X 10(9) cells, which represents a 3000-fold purification. The membrane-associated T3 binding protein is an acidic protein with a pI of 5.1 and an apparent molecular mass of 55,000 daltons determined by NaDodSO4/PAGE. Polyclonal antibodies against the 55-kDa protein were prepared and used in indirect immunofluorescence to show that the 55-kDa protein was mainly found in the nuclear envelope and endoplasmic reticulum. Images PMID:3006034

  17. Mapping a nucleolar targeting sequence of an RNA binding nucleolar protein, Nop25

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fujiwara, Takashi; Suzuki, Shunji; Kanno, Motoko

    2006-06-10

    Nop25 is a putative RNA binding nucleolar protein associated with rRNA transcription. The present study was undertaken to determine the mechanism of Nop25 localization in the nucleolus. Deletion experiments of Nop25 amino acid sequence showed Nop25 to contain a nuclear targeting sequence in the N-terminal and a nucleolar targeting sequence in the C-terminal. By expressing derivative peptides from the C-terminal as GFP-fusion proteins in the cells, a lysine and arginine residue-enriched peptide (KRKHPRRAQDSTKKPPSATRTSKTQRRRR) allowed a GFP-fusion protein to be transported and fully retained in the nucleolus. When the peptide was fused with cMyc epitope and expressed in the cells, amore » cMyc epitope was then detected in the nucleolus. Nop25 did not localize in the nucleolus by deletion of the peptide from Nop25. Furthermore, deletion of a subdomain (KRKHPRRAQ) in the peptide or amino acid substitution of lysine and arginine residues in the subdomain resulted in the loss of Nop25 nucleolar localization. These results suggest that the lysine and arginine residue-enriched peptide is the most prominent nucleolar targeting sequence of Nop25 and that the long stretch of basic residues might play an important role in the nucleolar localization of Nop25. Although Nop25 contained putative SUMOylation, phosphorylation and glycosylation sites, the amino acid substitution in these sites had no effect on the nucleolar localization, thus suggesting that these post-translational modifications did not contribute to the localization of Nop25 in the nucleolus. The treatment of the cells, which expressed a GFP-fusion protein with a nucleolar targeting sequence of Nop25, with RNase A resulted in a complete dislocation of the protein from the nucleolus. These data suggested that the nucleolar targeting sequence might therefore play an important role in the binding of Nop25 to RNA molecules and that the RNA binding of Nop25 might be essential for the nucleolar localization of Nop25.« less

  18. Ezrin is a cyclic AMP-dependent protein kinase anchoring protein.

    PubMed Central

    Dransfield, D T; Bradford, A J; Smith, J; Martin, M; Roy, C; Mangeat, P H; Goldenring, J R

    1997-01-01

    cAMP-dependent protein kinase (A-kinase) anchoring proteins (AKAPs) are responsible for the subcellular sequestration of the type II A-kinase. Previously, we identified a 78 kDa AKAP which was enriched in gastric parietal cells. We have now purified the 78 kDa AKAP to homogeneity from gastric fundic mucosal supernates using type II A-kinase regulatory subunit (RII) affinity chromatography. The purified 78 kDa AKAP was recognized by monoclonal antibodies against ezrin, the canalicular actin-associated protein. Recombinant ezrin produced in either Sf9 cells or bacteria also bound RII. Recombinant radixin and moesin, ezrin-related proteins, also bound RII in blot overlay. Analysis of recombinant truncations of ezrin mapped the RII binding site to a region between amino acids 373 and 439. This region contained a 14-amino-acid amphipathic alpha-helical putative RII binding region. A synthetic peptide containing the amphipathic helical region (ezrin409-438) blocked RII binding to ezrin, but a peptide with a leucine to proline substitution at amino acid 421 failed to inhibit RII binding. In mouse fundic mucosa, RII immunoreactivity redistributed from a predominantly cytosolic location in resting parietal cells, to a canalicular pattern in mucosa from animals stimulated with gastrin. These results demonstrate that ezrin is a major AKAP in gastric parietal cells and may function to tether type II A-kinase to a region near the secretory canaliculus. PMID:9009265

  19. Bolevenine, a toxic protein from the Japanese toadstool Boletus venenatus.

    PubMed

    Matsuura, Masanori; Yamada, Mina; Saikawa, Yoko; Miyairi, Kazuo; Okuno, Toshikatsu; Konno, Katsuhiro; Uenishi, Jun'ichi; Hashimoto, Kimiko; Nakata, Masaya

    2007-03-01

    A toxic protein, called bolevenine, was isolated from the toxic mushroom Boletus venenatus based on its lethal effects on mice. On SDS-PAGE, in either the presence or absence of 2-mercaptoethanol, this protein showed a single band of approximately 12 kDa. In contrast, based on gel filtration and MALDI-TOFMS, its relative molecular mass was estimated to be approximately 30 kDa and approximately 33 kDa, respectively, indicating that the protein consists of three identical subunits. This toxin exhibited its lethal activity following injection at 10mg/kg into mice. The N-terminal amino acid sequence was determined up to 18, and found to be similar to the previously reported bolesatine, a toxic compound isolated from Boletus satanas.

  20. Biochemical characterization of soluble proteins in pecan [Carya illinoinensis (Wangenh.) K. Koch].

    PubMed

    Venkatachalam, Mahesh; Roux, Kenneth H; Sathe, Shridhar K

    2008-09-10

    Pecans (cv. Desirable) contained approximately 10% protein on a dry weight basis. The minimum nitrogen solubility (5.9-7.5%) at 0.25-0.75 M trichloroacetic acid represented the nonprotein nitrogen. Among the solvents assessed for protein solubilization, 0.1 M NaOH was the most effective, while borate saline buffer (pH 8.45) was judged to be optimal for protein solubilization. The protein solubility was minimal in the pH range of 3-7 and significantly increased on either side of this pH range. Increasing the NaCl concentration from 0 to 4 M significantly improved ( approximately 8-fold increase) protein solubilization. Following Osborne protein fractionation, the alkali-soluble glutelin fraction (60.1%) accounted for a major portion of pecan proteins followed by globulin (31.5%), prolamin (3.4%), and albumin (1.5%), respectively. The majority of pecan polypeptides were in the molecular mass range of 12-66 kDa and in the pI range of 4.0-8.3. The pecan globulin fraction was characterized by the presence of several glycoprotein polypeptides. Lysine was the first limiting essential amino acid in the defatted flour, globulin, prolamin, and alkaline glutelin fractions. Leucine and tryptophan were the first limiting essential amino acids in albumin and acid glutelin fractions, respectively. Rabbit polyclonal antibodies detected a range of pecan polypeptides in the 12-60 kDa range, of which the globulin fraction contained the most reactive polypeptides.

  1. Molluscan mega-hemocyanin: an ancient oxygen carrier tuned by a ~550 kDa polypeptide

    PubMed Central

    2010-01-01

    Background The allosteric respiratory protein hemocyanin occurs in gastropods as tubular di-, tri- and multimers of a 35 × 18 nm, ring-like decamer with a collar complex at one opening. The decamer comprises five subunit dimers. The subunit, a 400 kDa polypeptide, is a concatenation of eight paralogous functional units. Their exact topology within the quaternary structure has recently been solved by 3D electron microscopy, providing a molecular model of an entire didecamer (two conjoined decamers). Here we study keyhole limpet hemocyanin (KLH2) tridecamers to unravel the exact association mode of the third decamer. Moreover, we introduce and describe a more complex type of hemocyanin tridecamer discovered in fresh/brackish-water cerithioid snails (Leptoxis, Melanoides, Terebralia). Results The "typical" KLH2 tridecamer is partially hollow, whereas the cerithioid tridecamer is almost completely filled with material; it was therefore termed "mega-hemocyanin". In both types, the staggering angle between adjoining decamers is 36°. The cerithioid tridecamer comprises two typical decamers based on the canonical 400 kDa subunit, flanking a central "mega-decamer" composed of ten unique ~550 kDa subunits. The additional ~150 kDa per subunit substantially enlarge the internal collar complex. Preliminary oxygen binding measurements indicate a moderate hemocyanin oxygen affinity in Leptoxis (p50 ~9 mmHg), and a very high affinity in Melanoides (~3 mmHg) and Terebralia (~2 mmHg). Species-specific and individual variation in the proportions of the two subunit types was also observed, leading to differences in the oligomeric states found in the hemolymph. Conclusions In cerithioid hemocyanin tridecamers ("mega-hemocyanin") the collar complex of the central decamer is substantially enlarged and modified. The preliminary O2 binding curves indicate that there are species-specific functional differences in the cerithioid mega-hemocyanins which might reflect different physiological

  2. Crystallization and preliminary X-ray diffraction analysis of the P3 RNA domain of yeast ribonuclease MRP in a complex with RNase P/MRP protein components Pop6 and Pop7.

    PubMed

    Perederina, Anna; Esakova, Olga; Quan, Chao; Khanova, Elena; Krasilnikov, Andrey S

    2010-01-01

    Eukaryotic ribonucleases P and MRP are closely related RNA-based enzymes which contain a catalytic RNA component and several protein subunits. The roles of the protein subunits in the structure and function of eukaryotic ribonucleases P and MRP are not clear. Crystals of a complex that included a circularly permuted 46-nucleotide-long P3 domain of the RNA component of Saccharomyces cerevisiae ribonuclease MRP and selenomethionine derivatives of the shared ribonuclease P/MRP protein components Pop6 (18.2 kDa) and Pop7 (15.8 kDa) were obtained using the sitting-drop vapour-diffusion method. The crystals belonged to space group P4(2)22 (unit-cell parameters a = b = 127.2, c = 76.8 A, alpha = beta = gamma = 90 degrees ) and diffracted to 3.25 A resolution.

  3. A recombinant 63-kDa form of Bacillus anthracis protective antigen produced in the yeast Saccharomyces cerevisiae provides protection in rabbit and primate inhalational challenge models of anthrax infection.

    PubMed

    Hepler, Robert W; Kelly, Rosemarie; McNeely, Tessie B; Fan, Hongxia; Losada, Maria C; George, Hugh A; Woods, Andrea; Cope, Leslie D; Bansal, Alka; Cook, James C; Zang, Gina; Cohen, Steven L; Wei, Xiaorong; Keller, Paul M; Leffel, Elizabeth; Joyce, Joseph G; Pitt, Louise; Schultz, Loren D; Jansen, Kathrin U; Kurtz, Myra

    2006-03-06

    Infection by Bacillus anthracis is preventable by prophylactic vaccination with several naturally derived and recombinant vaccine preparations. Existing data suggests that protection is mediated by antibodies directed against the protective antigen (PA) component of the anthrax toxin complex. PA is an 83-kDa protein cleaved in vivo to yield a biologically active 63-kDa protein. In an effort to evaluate the potential of yeast as an expression system for the production of recombinant PA, and to determine if the yeast-purified rPA63 can protect from a lethal inhalational challenge, the sequence of the 63-kDa form of PA was codon-optimized and expressed in the yeast Saccharomyces cerevisiae. Highly purified rPA63 isolated from Saccharomyces under denaturing conditions demonstrated reduced biological activity in a macrophage-killing assay compared to non-denatured rPA83 purified from Escherichia coli. Rabbits and non-human primates (NHP) immunized with rPA63 and later challenged with a lethal dose of B. anthracis spores were generally protected from infection. These results indicate that epitopes present in the 63-kDa from of PA can protect rabbits and non-human primates from a lethal spore challenge, and further suggest that a fully functional rPA63 is not required in order to provide these epitopes.

  4. The potential for PVs in Greek commercial buildings

    NASA Astrophysics Data System (ADS)

    Samouil, Chris

    The photovoltaic sector has been growing explosively, worldwide, for the past few years. At present, grid-connected installations dominate the world market. The photovoltaic technology, types of systems, applications and the market of PVs are presented, placing emphasis on installations regarding the building sector. The main focus of the project is concentrated on Greece. The fact that Greece has favourable natural conditions for the exploitation of solar energy, coupled with the support scheme on phototovoltaics introduced with the new law on renewable energy sources voted in June 2006, makes it very interesting to invest in the Greek PV market. Using a newly built office building in Athens with a roof-top PV installation as a case study, this project looks at the viability of grid-connected systems in the building sector. The annual energy output of the system and CO2 emissions reduction were modelled. Embodied energy, installation cost and annual savings were also considered to determine payback periods. The economic payback period of the system was found to be shorter than its lifetime at 16.2 years, reducing to 9.7 years when grants were included. The carbon payback period was calculated at 6.3 years. A sensitivity analysis on the effect of different factors affecting the viability of the PV installation was carried out. Assuming constant electricity rate increases or a more favourable location for the project the results are more attractive. The same case study in Crete would have a payback period reduced by almost 20% compared to that in Athens. A method to extrapolate the findings for the whole building sector of Attica is proposed as a future research project. As an indication it is found that 60,000 similar to the base case roof-top PV systems can produce around 3.1% of the country's thermally produced electricity and save 0.9% of its CO2 emissions. Finally, the strengths and weeknesses of the new RES law are identified and suggestions are made in order

  5. Volumetric Interpretation of Protein Adsorption: Interfacial Packing of Protein Adsorbed to Hydrophobic Surfaces from Surface-Saturating Solution Concentrations

    PubMed Central

    Kao, Ping; Parhi, Purnendu; Krishnan, Anandi; Noh, Hyeran; Haider, Waseem; Tadigadapa, Srinivas; Allara, David L.; Vogler, Erwin A.

    2010-01-01

    The maximum capacity of a hydrophobic adsorbent is interpreted in terms of square or hexagonal (cubic and face-centered-cubic, FCC) interfacial packing models of adsorbed blood proteins in a way that accommodates experimental measurements by the solution-depletion method and quartz-crystal-microbalance (QCM) for the human proteins serum albumin (HSA, 66 kDa), immunoglobulin G (IgG, 160 kDa), fibrinogen (Fib, 341 kDa), and immunoglobulin M (IgM, 1000 kDa). A simple analysis shows that adsorbent capacity is capped by a fixed mass/volume (e.g. mg/mL) surface-region (interphase) concentration and not molar concentration. Nearly analytical agreement between the packing models and experiment suggests that, at surface saturation, above-mentioned proteins assemble within the interphase in a manner that approximates a well-ordered array. HSA saturates a hydrophobic adsorbent with the equivalent of a single square-or-hexagonally-packed layer of hydrated molecules whereas the larger proteins occupy two-or-more layers, depending on the specific protein under consideration and analytical method used to measure adsorbate mass (solution depletion or QCM). Square-or-hexagonal (cubic and FCC) packing models cannot be clearly distinguished by comparison to experimental data. QCM measurement of adsorbent capacity is shown to be significantly different than that measured by solution depletion for similar hydrophobic adsorbents. The underlying reason is traced to the fact that QCM measures contribution of both core protein, water of hydration, and interphase water whereas solution depletion measures only the contribution of core protein. It is further shown that thickness of the interphase directly measured by QCM systematically exceeds that inferred from solution-depletion measurements, presumably because the static model used to interpret solution depletion does not accurately capture the complexities of the viscoelastic interfacial environment probed by QCM. PMID:21035180

  6. Volumetric interpretation of protein adsorption: interfacial packing of protein adsorbed to hydrophobic surfaces from surface-saturating solution concentrations.

    PubMed

    Kao, Ping; Parhi, Purnendu; Krishnan, Anandi; Noh, Hyeran; Haider, Waseem; Tadigadapa, Srinivas; Allara, David L; Vogler, Erwin A

    2011-02-01

    The maximum capacity of a hydrophobic adsorbent is interpreted in terms of square or hexagonal (cubic and face-centered-cubic, FCC) interfacial packing models of adsorbed blood proteins in a way that accommodates experimental measurements by the solution-depletion method and quartz-crystal-microbalance (QCM) for the human proteins serum albumin (HSA, 66 kDa), immunoglobulin G (IgG, 160 kDa), fibrinogen (Fib, 341 kDa), and immunoglobulin M (IgM, 1000 kDa). A simple analysis shows that adsorbent capacity is capped by a fixed mass/volume (e.g. mg/mL) surface-region (interphase) concentration and not molar concentration. Nearly analytical agreement between the packing models and experiment suggests that, at surface saturation, above-mentioned proteins assemble within the interphase in a manner that approximates a well-ordered array. HSA saturates a hydrophobic adsorbent with the equivalent of a single square or hexagonally-packed layer of hydrated molecules whereas the larger proteins occupy two-or-more layers, depending on the specific protein under consideration and analytical method used to measure adsorbate mass (solution depletion or QCM). Square or hexagonal (cubic and FCC) packing models cannot be clearly distinguished by comparison to experimental data. QCM measurement of adsorbent capacity is shown to be significantly different than that measured by solution depletion for similar hydrophobic adsorbents. The underlying reason is traced to the fact that QCM measures contribution of both core protein, water of hydration, and interphase water whereas solution depletion measures only the contribution of core protein. It is further shown that thickness of the interphase directly measured by QCM systematically exceeds that inferred from solution-depletion measurements, presumably because the static model used to interpret solution depletion does not accurately capture the complexities of the viscoelastic interfacial environment probed by QCM. Copyright © 2010

  7. Mature parasite-infected erythrocyte surface antigen (MESA) of Plasmodium falciparum binds to the 30-kDa domain of protein 4.1 in malaria-infected red blood cells.

    PubMed

    Waller, Karena L; Nunomura, Wataru; An, Xiuli; Cooke, Brian M; Mohandas, Narla; Coppel, Ross L

    2003-09-01

    The Plasmodium falciparum mature parasite-infected erythrocyte surface antigen (MESA) is exported from the parasite to the infected red blood cell (IRBC) membrane skeleton, where it binds to protein 4.1 (4.1R) via a 19-residue MESA sequence. Using purified RBC 4.1R and recombinant 4.1R fragments, we show MESA binds the 30-kDa region of RBC 4.1R, specifically to a 51-residue region encoded by exon 10 of the 4.1R gene. The 3D structure of this region reveals that the MESA binding site overlaps the region of 4.1R involved in the p55, glycophorin C, and 4.1R ternary complex. Further binding studies using p55, 4.1R, and MESA showed competition between p55 and MESA for 4.1R, implying that MESA bound at the IRBC membrane skeleton may modulate normal 4.1R and p55 interactions in vivo. Definition of minimal binding domains involved in critical protein interactions in IRBCs may aid the development of novel therapies for falciparum malaria.

  8. Immunogenic properties of a recombinant fusion protein containing the C-terminal 19 kDa of Plasmodium falciparum merozoite surface protein-1 and the innate immunity agonist FliC flagellin of Salmonella typhimurium.

    PubMed

    Bargieri, Daniel Y; Leite, Juliana A; Lopes, Stefanie C P; Sbrogio-Almeida, Maria Elisabete; Braga, Catarina J M; Ferreira, Luis C S; Soares, Irene S; Costa, Fabio T M; Rodrigues, Mauricio M

    2010-04-01

    In a recent study, we demonstrated the immunogenic properties of a new malaria vaccine polypeptide based on a 19 kDa C-terminal fragment of the merozoite surface protein-1 (MSP1(19)) from Plasmodium vivax and an innate immunity agonist, the Salmonella enterica serovar Typhimurium flagellin (FliC). Herein, we tested whether the same strategy, based on the MSP1(19) component of the deadly malaria parasite Plasmodium falciparum, could also generate a fusion polypeptide with enhanced immunogenicity. The His(6)FliC-MSP1(19) fusion protein was expressed from a recombinant Escherichia coli and showed preserved in vitro TLR5-binding activity. In contrast to animals injected with His(6)MSP1(19), mice subcutaneously immunised with the recombinant His(6)FliC-MSP1(19) developed strong MSP1(19)-specific systemic antibody responses with a prevailing IgG1 subclass. Incorporation of other adjuvants, such as CpG ODN 1826, complete and incomplete Freund's adjuvants or Quil-A, improved the IgG responses after the second, but not the third, immunising dose. It also resulted in a more balanced IgG subclass response, as evaluated by the IgG1/IgG2c ratio, and higher cell-mediated immune response, as determined by the detection of antigen-specific interferon-gamma secretion by immune spleen cells. MSP1(19)-specific antibodies recognised not only the recombinant protein, but also the native protein expressed on the surface of P. falciparum parasites. Finally, sera from rabbits immunised with the fusion protein alone inhibited the in vitro growth of three different P. falciparum strains. In summary, these results extend our previous observations and further demonstrate that fusion of the innate immunity agonist FliC to Plasmodium antigens is a promising alternative to improve their immunogenicity. (c) 2010 Elsevier Ltd. All rights reserved.

  9. Studies on Antifungal Potential, Primary Characterization and Mode of Action of a De Novo Cytoplasmic Protein (EAF) from Human Commensal Escherichia coli Against Aspergillus spp.

    PubMed

    Balhara, Meenakshi; Ruhil, Sonam; Dhankhar, Sandeep; Chhillar, Anil K

    2015-01-01

    A de novo protein named as EAF (Escherichia antifungal protein) from the cytoplasmic pool of an Escherichia coli strain (MTCC 1652), has been purified to homogeneity using anion exchange (Q-XL Sepharose) and cation exchange (SP-Sepharose) chromatography. The MIC (minimum inhibitory concentration) values of purified protein against A. fumigatus (the major pathogenic species) were found to be comparable with standard drugs i.e. 3.90 µg/ml, 3.90 µg/ml and 1.25 µg/disc via microbroth dilution assay (MDA), percentage spore germination inhibition (PSGI) and disc diffusion assay (DDA) respectively. Toxicity results confirmed that it causes no haemolysis against human RBCs upto a concentration of 1000.0 µg/ml as compared to Amphotericin B (conventional antifungal drug) that causes hundred percent haemolysis at a concentration of 37.50 µg/ml only.The purified protein demonstrated a molecular mass of 28 kDa on SDS-PAGE which was further authenticated by MALDI-TOF. Proteomic and bioinformatics studies deciphered its significant homology (72 %) with chain A-D-ribose binding protein (cluster 2 sugar binding periplasmic proteins; sequence homologues of transcription regulatory proteins) from E. coli. Single dimensional page analysis of A. fumigatusproteins with due effect of EAF (at MIC50) revealed the inhibition of two major proteins; a heat shock protein 70-Hsp70 (68 kDa); having role in protein folding and functioning andphenylanalyl-t RNA synthetase PodG subunit protein (74 kDa); involved in growth polarity in fungi. Scanning electron microscopic studies depicted homologous results. We suggest that EAF most likely belongs to a new group of proteins with potent antifungal characteristics, negligible toxicity and targeting vital proteins of fungal metabolism.

  10. Age-Related Decrease in Heat Shock 70-kDa Protein 8 in Cerebrospinal Fluid Is Associated with Increased Oxidative Stress.

    PubMed

    Loeffler, David A; Klaver, Andrea C; Coffey, Mary P; Aasly, Jan O; LeWitt, Peter A

    2016-01-01

    Age-associated declines in protein homeostasis mechanisms ("proteostasis") are thought to contribute to age-related neurodegenerative disorders. The increased oxidative stress which occurs with aging can activate a key proteostatic process, chaperone-mediated autophagy. This study investigated age-related alteration in cerebrospinal fluid (CSF) concentrations of heat shock 70-kDa protein 8 (HSPA8), a molecular chaperone involved in proteostatic mechanisms including chaperone-mediated autophagy, and its associations with indicators of oxidative stress (8-hydroxy-2'-deoxyguanosine [8-OHdG] and 8-isoprostane) and total anti-oxidant capacity. We examined correlations between age, HSPA8, 8-OHdG, 8-isoprostane, and total antioxidant capacity (TAC) in CSF samples from 34 healthy subjects ranging from 20 to 75 years of age. Age was negatively associated with HSPA8 (ρ = -0.47; p = 0.005). An age-related increase in oxidative stress was indicated by a positive association between age and 8-OHdG (ρ = 0.61; p = 0.0001). HSPA8 was moderately negatively associated with 8-OHdG (ρ = -0.58; p = 0.0004). Age and HSPA8 were weakly associated with 8-isoprostane and TAC (range of ρ values: -0.15 to 0.16). Our findings in this exploratory study suggest that during healthy aging, CSF HSPA8 may decrease, perhaps due in part to an increase in oxidative stress. Our results also suggest that 8-OHdG may be more sensitive than 8-isoprostane for measuring oxidative stress in CSF. Further studies are indicated to determine if our findings can be replicated with a larger cohort, and if the age-related decrease in HSPA8 in CSF is reflected by a similar change in the brain.

  11. Heat shock protein 70 kDa: molecular biology, biochemistry, and physiology.

    PubMed

    Kiang, J G; Tsokos, G C

    1998-11-01

    Heat shock proteins (HSPs) are detected in all cells, prokaryotic and eukaryotic. In vivo and in vitro studies have shown that various stressors transiently increase production of HSPs as protection against harmful insults. Increased levels of HSPs occur after environmental stresses, infection, normal physiological processes, and gene transfer. Although the mechanisms by which HSPs protect cells are not clearly understood, their expression can be modulated by cell signal transducers, such as changes in intracellular pH, cyclic AMP, Ca2+, Na+, inositol trisphosphate, protein kinase C, and protein phosphatases. Most of the HSPs interact with other proteins in cells and alter their function. These and other protein-protein interactions may mediate the little understood effects of HSPs on various cell functions. In this review, we focus on the structure of the HSP-70 family (HSP-70s), regulation of HSP-70 gene expression, their cytoprotective effects, and the possibility of regulating HSP-70 expression through modulation of signal transduction pathways. The clinical importance and therapeutic potential of HSPs are discussed.

  12. Sarcoplasmic calcium-binding protein: identification as a new allergen of the black tiger shrimp Penaeus monodon.

    PubMed

    Shiomi, Kazuo; Sato, Yuichiro; Hamamoto, Shohei; Mita, Hajime; Shimakura, Kuniyoshi

    2008-01-01

    Tropomyosin and arginine kinase have been identified as crustacean allergens. During purification of arginine kinase from black tiger shrimp Penaeus monodon, we found a new allergen of 20-kDa. A 20-kDa allergen was purified from the abdominal muscle of black tiger shrimp by salting-out, anion-exchange HPLC and reverse-phase HPLC. Following digestion of the 20-kDa allergen with lysyl endopeptidase, peptide fragments were isolated by reverse-phase HPLC, and 2 of them were sequenced. The 20-kDa allergen, together with tropomyosin and arginine kinase purified from black tiger shrimp, was evaluated for IgE reactivity by ELISA. Five species of crustaceans (kuruma shrimp, American lobster, pink shrimp, king crab and snow crab) were surveyed for the 20-kDa allergen by immunoblotting. The 20-kDa allergen was purified from black tiger shrimp and identified as a sarcoplasmic calcium-binding protein (SCP) based on the determined amino acid sequences of 2 enzymatic fragments. Of 16 sera from crustacean-allergic patients, 8 and 13 reacted to SCP and tropomyosin, respectively; the reactivity to arginine kinase was weakly recognized with 10 sera. In immunoblotting, an IgE-reactive 20-kDa protein was also detected in kuruma shrimp, American lobster and pink shrimp but not in 2 species of crab. Preadsorption of the sera with black tiger shrimp SCP abolished the IgE reactivity of the 20-kDa protein, suggesting the 20-kDa protein to be an SCP. SCP is a new crustacean allergen, and distribution of IgE-reactive SCP is probably limited to shrimp and crayfish. (c) 2008 S. Karger AG, Basel.

  13. Membrane-Bound Tomato Mosaic Virus Replication Proteins Participate in RNA Synthesis and Are Associated with Host Proteins in a Pattern Distinct from Those That Are Not Membrane Bound

    PubMed Central

    Nishikiori, Masaki; Dohi, Koji; Mori, Masashi; Meshi, Tetsuo; Naito, Satoshi; Ishikawa, Masayuki

    2006-01-01

    Extracts of vacuole-depleted, tomato mosaic virus (ToMV)-infected plant protoplasts contained an RNA-dependent RNA polymerase (RdRp) that utilized an endogenous template to synthesize ToMV-related positive-strand RNAs in a pattern similar to that observed in vivo. Despite the fact that only minor fractions of the ToMV 130- and 180-kDa replication proteins were associated with membranes, the RdRp activity was exclusively associated with membranes. A genome-sized, negative-strand RNA template was associated with membranes and was resistant to micrococcal nuclease unless treated with detergents. Non-membrane-bound replication proteins did not exhibit RdRp activity, even in the presence of ToMV RNA. While the non-membrane-bound replication proteins remained soluble after treatment with Triton X-100, the same treatment made the membrane-bound replication proteins in a form that precipitated upon low-speed centrifugation. On the other hand, the detergent lysophosphatidylcholine (LPC) efficiently solubilized the membrane-bound replication proteins. Upon LPC treatment, the endogenous template-dependent RdRp activity was reduced and exogenous ToMV RNA template-dependent RdRp activity appeared instead. This activity, as well as the viral 130-kDa protein and the host proteins Hsp70, eukaryotic translation elongation factor 1A (eEF1A), TOM1, and TOM2A copurified with FLAG-tagged viral 180-kDa protein from LPC-solubilized membranes. In contrast, Hsp70 and only small amounts of the 130-kDa protein and eEF1A copurified with FLAG-tagged non-membrane-bound 180-kDa protein. These results suggest that the viral replication proteins are associated with the intracellular membranes harboring TOM1 and TOM2A and that this association is important for RdRp activity. Self-association of the viral replication proteins and their association with other host proteins may also be important for RdRp activity. PMID:16912296

  14. Antitumor activity against murine lymphoma L5178Y model of proteins from cacao (Theobroma cacao L.) seeds in relation with in vitro antioxidant activity

    PubMed Central

    2010-01-01

    Background Recently, proteins and peptides have become an added value to foodstuffs due to new knowledge about its structural analyses as related to antioxidant and anticancer activity. Our goal was to evaluate if protein fractions from cacao seeds show antitumor activity on lymphoma murine L5178Y model. The antioxidant activity of these fractions was also evaluated with the aim of finding a correlation with the antitumor activity. Methods Differential extraction of proteins from unfermented and semi-fermented-dry cacao seeds was performed and characterized by SDS-PAGE and FPLC size-exclusion chromatography. Antitumor activity was evaluated against murine lymphoma L5178Y in BALB/c mice (6 × 104 cells i.p.), with a treatment oral dose of 25 mg/kg/day of each protein fraction, over a period of 15 days. Antioxidant activity was evaluated by the ABTS+ and ORAC-FL assays. Results Albumin, globulin and glutelin fractions from both cacao seed type were obtained by differential solubility extraction. Glutelins were the predominant fraction. In the albumin fraction, polypeptides of 42.3 and 8.5 kDa were found in native conditions, presumably in the form of two peptide chains of 21.5 kDa each one. The globulin fraction presented polypeptides of 86 and 57 kDa in unfermented cacao seed that produced the specific-cacao aroma precursors, and after fermentation the polypeptides were of 45 and 39 kDa. The glutelin fraction presented proteins >200 kDa and globulins components <100 KDa in lesser proportion. Regarding the semifermented-dry cacao seed, it was observed that the albumin fraction showed antitumoral activity, since it caused significant decreases (p < 0.05) in the ascetic fluid volume and packed cell volume, inhibiting cell growth in 59.98 ± 13.6% at 60% of the population; while the greatest antioxidant capacity due to free radical scavenging capacity was showed by the albumin and glutelin fraction in both methods assayed. Conclusion This study is the first report on

  15. Overexpression of inducible 70-kDa heat shock protein in mouse improves structural and functional recovery of skeletal muscles from atrophy.

    PubMed

    Miyabara, Elen H; Nascimento, Tabata L; Rodrigues, Débora C; Moriscot, Anselmo S; Davila, Wilmer F; AitMou, Younss; deTombe, Pieter P; Mestril, Ruben

    2012-04-01

    Heat shock proteins play a key regulatory role in cellular defense. To investigate the role of the inducible 70-kDa heat shock protein (HSP70) in skeletal muscle atrophy and subsequent recovery, soleus (SOL) and extensor digitorum longus (EDL) muscles from overexpressing HSP70 transgenic mice were immobilized for 7 days and subsequently released from immobilization and evaluated after 7 days. Histological analysis showed that there was a decrease in cross-sectional area of type II myofiber from EDL and types I and II myofiber from SOL muscles at 7-day immobilization in both wild-type and HSP70 mice. At 7-day recovery, EDL and SOL myofibers from HSP70 mice, but not from wild-type mice, recovered their size. Muscle tetanic contraction decreased only in SOL muscles from wild-type mice at both 7-day immobilization and 7-day recovery; however, it was unaltered in the respective groups from HSP70 mice. Although no effect in a fatigue protocol was observed among groups, we noticed a better contractile performance of EDL muscles from overexpressing HSP70 groups as compared to their matched wild-type groups. The number of NCAM positive-satellite cells reduced after immobilization and recovery in both EDL and SOL muscles from wild-type mice, but it was unchanged in the muscles from HSP70 mice. These results suggest that HSP70 improves structural and functional recovery of skeletal muscle after disuse atrophy, and this effect might be associated with preservation of satellite cell amount.

  16. Thermoase-Derived Flaxseed Protein Hydrolysates and Membrane Ultrafiltration Peptide Fractions Have Systolic Blood Pressure-Lowering Effects in Spontaneously Hypertensive Rats

    PubMed Central

    Nwachukwu, Ifeanyi D.; Girgih, Abraham T.; Malomo, Sunday A.; Onuh, John O.; Aluko, Rotimi E.

    2014-01-01

    Thermoase-digested flaxseed protein hydrolysate (FPH) samples and ultrafiltration membrane-separated peptide fractions were initially evaluated for in vitro inhibition of angiotensin I-converting enzyme (ACE) and renin activities. The two most active FPH samples and their corresponding peptide fractions were subsequently tested for in vivo antihypertensive activity in spontaneously hypertensive rats (SHR). The FPH produced with 3% thermoase digestion showed the highest ACE- and renin-inhibitory activities. Whereas membrane ultrafiltration resulted in significant (p < 0.05) increases in ACE inhibition by the <1 and 1–3 kDa peptides, only a marginal improvement in renin-inhibitory activity was observed for virtually all the samples after membrane ultrafiltration. The FPH samples and membrane fractions were also effective in lowering systolic blood pressure (SBP) in SHR with the largest effect occurring after oral administration (200 mg/kg body weight) of the 1–3 kDa peptide fraction of the 2.5% FPH and the 3–5 kDa fraction of the 3% FPH. Such potent SBP-lowering capacity indicates the potential of flaxseed protein-derived bioactive peptides as ingredients for the formulation of antihypertensive functional foods and nutraceuticals. PMID:25302619

  17. Identification of an immunogenic protein of Actinobacillus seminis that is present in microvesicles

    PubMed Central

    2006-01-01

    Abstract Actinobacillus seminis is a gram-negative bacterium of the Pasteurellaceae family that is involved in ovine epididymitis. Looking for a protein specific to this species, we determined the protein profile of subcellular fractions of A. seminis (American Type Culture Collection number 15768): proteins from the outer membrane (OMPs), inner membrane (IMPs), and cytoplasm (CPs). These profiles provide the first data, to our knowledge, regarding subcellular fractions of A. seminis. In the OMP fraction, we identified a protein with a molecular mass of 75 kDa that proved to be immunogenic and apparently specific for A. seminis. This conclusion was based on the reaction of hyperimmune serum of rabbits inoculated with whole cells of A. seminis that was tested against sonicated complete cells of reference strains and field isolates of Brucella ovis, Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni. No protein of these bacteria cross-reacted with the 75-kDa protein of A. seminis. Furthermore, when each type of hyperimmune serum was tested against the sonicated cells and each of the subcellular fractions of A. seminis, it did not recognize the A. seminis 75-kDa protein. We also isolated and identified this protein in microvesicles released to the culture supernatant. The results suggest that the 75-kDa protein could be used to establish a diagnostic test specific for ovine epididymitis caused by A. seminis. PMID:16548331

  18. The VPH1 gene encodes a 95-kDa integral membrane polypeptide required for in vivo assembly and activity of the yeast vacuolar H(+)-ATPase.

    PubMed

    Manolson, M F; Proteau, D; Preston, R A; Stenbit, A; Roberts, B T; Hoyt, M A; Preuss, D; Mulholland, J; Botstein, D; Jones, E W

    1992-07-15

    Yeast vacuolar acidification-defective (vph) mutants were identified using the pH-sensitive fluorescence of 6-carboxyfluorescein diacetate (Preston, R. A., Murphy, R. F., and Jones, E. W. (1989) Proc. Natl. Acad. Sci. U.S.A. 86, 7027-7031). Vacuoles purified from yeast bearing the vph1-1 mutation had no detectable bafilomycin-sensitive ATPase activity or ATP-dependent proton pumping. The peripherally bound nucleotide-binding subunits of the vacuolar H(+)-ATPase (60 and 69 kDa) were no longer associated with vacuolar membranes yet were present in wild type levels in yeast whole cell extracts. The VPH1 gene was cloned by complementation of the vph1-1 mutation and independently cloned by screening a lambda gt11 expression library with antibodies directed against a 95-kDa vacuolar integral membrane protein. Deletion disruption of the VPH1 gene revealed that the VPH1 gene is not essential for viability but is required for vacuolar H(+)-ATPase assembly and vacuolar acidification. VPH1 encodes a predicted polypeptide of 840 amino acid residues (molecular mass 95.6 kDa) and contains six putative membrane-spanning regions. Cell fractionation and immunodetection demonstrate that Vph1p is a vacuolar integral membrane protein that co-purifies with vacuolar H(+)-ATPase activity. Multiple sequence alignments show extensive homology over the entire lengths of the following four polypeptides: Vph1p, the 116-kDa polypeptide of the rat clathrin-coated vesicles/synaptic vesicle proton pump, the predicted polypeptide encoded by the yeast gene STV1 (Similar To VPH1, identified as an open reading frame next to the BUB2 gene), and the TJ6 mouse immune suppressor factor.

  19. The integral and extrinsic bioactive proteins in the aqueous extracted soybean oil bodies.

    PubMed

    Zhao, Luping; Chen, Yeming; Cao, Yanyun; Kong, Xiangzhen; Hua, Yufei

    2013-10-09

    Soybean oil bodies (OBs), naturally pre-emulsified soybean oil, have been examined by many researchers owing to their great potential utilizations in food, cosmetics, pharmaceutical, and other applications requiring stable oil-in-water emulsions. This study was the first time to confirm that lectin, Gly m Bd 28K (Bd 28K, one soybean allergenic protein), Kunitz trypsin inhibitor (KTI), and Bowman-Birk inhibitor (BBI) were not contained in the extracted soybean OBs even by neutral pH aqueous extraction. It was clarified that the well-known Gly m Bd 30K (Bd 30K), another soybean allergenic protein, was strongly bound to soybean OBs through a disulfide bond with 24 kDa oleosin. One steroleosin isoform (41 kDa) and two caleosin isoforms (27 kDa, 29 kDa), the integral bioactive proteins, were confirmed for the first time in soybean OBs, and a considerable amount of calcium, necessary for the biological activities of caleosin, was strongly bound to OBs. Unexpectedly, it was found that 24 kDa and 18 kDa oleosins could be hydrolyzed by an unknown soybean endoprotease in the extracted soybean OBs, which might give some hints for improving the enzyme-assisted aqueous extraction processing of soybean free oil.

  20. High-resolution NMR spectroscopy of encapsulated proteins dissolved in low-viscosity fluids

    PubMed Central

    Nucci, Nathaniel V.; Valentine, Kathleen G.; Wand, A. Joshua

    2014-01-01

    High-resolution multi-dimensional solution NMR is unique as a biophysical and biochemical tool in its ability to examine both the structure and dynamics of macromolecules at atomic resolution. Conventional solution NMR approaches, however, are largely limited to examinations of relatively small (< 25 kDa) molecules, mostly due to the spectroscopic consequences of slow rotational diffusion. Encapsulation of macromolecules within the protective nanoscale aqueous interior of reverse micelles dissolved in low viscosity fluids has been developed as a means through which the ‘slow tumbling problem’ can be overcome. This approach has been successfully applied to diverse proteins and nucleic acids ranging up to 100 kDa, considerably widening the range of biological macromolecules to which conventional solution NMR methodologies may be applied. Recent advances in methodology have significantly broadened the utility of this approach in structural biology and molecular biophysics. PMID:24656086

  1. Isolation and characterization of a dual function protein from Allium sativum bulbs which exhibits proteolytic and hemagglutinating activities.

    PubMed

    Parisi, Mónica G; Moreno, Silvia; Fernández, Graciela

    2008-04-01

    A dual function protein was isolated from Allium sativum bulbs and was characterized. The protein had a molecular mass of 25-26 kDa under non-reducing conditions, whereas two polypeptide chains of 12.5+/-0.5 kDa were observed under reducing conditions. E-64 and leupeptin inhibited the proteolytic activity of the protein, which exhibited characteristics similar to cysteine peptidase. The enzyme exhibited substrate specificity and hydrolyzed natural substrates such as alpha-casein (K(m): 23.0 microM), azocasein, haemoglobin and gelatin. It also showed a high affinity for synthetic peptides such as Cbz-Ala-Arg-Arg-OMe-beta-Nam (K(m): 55.24 microM, k(cat): 0.92 s(-1)). The cysteine peptidase activity showed a remarkable stability after incubation at moderate temperatures (40-50 degrees C) over a pH range of 5.5-6.5. The N-terminus of the protein displayed a 100% sequence similarity to the sequences of a mannose-binding lectin isolated from garlic bulbs. Moreover, the purified protein was retained in the chromatographic column when Con-A Sepharose affinity chromatography was performed and the protein was able to agglutinate trypsin-treated rabbit red cells. Therefore, our results indicate the presence of an additional cysteine peptidase activity on a lectin previously described.

  2. Membrane skeletal proteins and their integral membrane protein anchors are targets for tyrosine and threonine kinases in Euglena.

    PubMed

    Fazio, M J; Da Silva, A C; Rosiere, T K; Bouck, G B

    1995-01-01

    Proteins of the membrane skeleton of Euglena gracilis were extensively phosphorylated in vivo and in vitro after incubation with [32P]-orthophosphate or gamma-[32P] ATP. Endogenous protein threonine/serine activity phosphorylated the major membrane skeletal proteins (articulins) and the putative integral membrane protein (IP39) anchor for articulins. The latter was also the major target for endogenous protein tyrosine kinase activity. A cytoplasmic domain of IP39 was specifically phosphorylated, and removal of this domain with papain eliminated the radiolabeled phosphoamino acids and eliminated or radically shifted the PI of the multiple isoforms of IP39. In gel kinase assays IP39 autophosphorylated and a 25 kDa protein which does not autophosphorylate was identified as a threonine/serine (casein) kinase. Plasma membranes from the membrane skeletal protein complex contained threonine/serine (casein) kinase activity, and cross-linking experiments suggested that IP39 was the likely source for this membrane activity. pH optima, cation requirements and heparin sensitivity of the detergent solubilized membrane activity were determined. Together these results suggest that protein kinases may be important modulators of protein assembly and function of the membrane skeleton of these protistan cells.

  3. Peculiarities of hemoglobin interaction with serum proteins of mice with Ehrlich carcinoma.

    PubMed

    Sitdikova, S M; Amandzholov, B S; Serebryakova, M V; Zhdanovich, M Yu; Kiselevskii, M V; Donenko, F V

    2006-05-01

    In male C57Bl/6 mice with transplanted Ehrlich carcinoma, hemoglobin forms a complex with serum proteins characterized by a molecular weight of about 300 kDa. The complex incorporates proteins weighing 100, 68, 65, and 15 kDa identified by MALDI-TOF mass spectrometry as haptoglobin, serum albumin, gi/26341396 nameless protein Mus musculus, and alpha-hemoglobin, respectively. This complex can possess biological activity and contribute to the control of tumor growth.

  4. Structure of TatA Paralog, TatE, Suggests a Structurally Homogeneous Form of Tat Protein Translocase That Transports Folded Proteins of Differing Diameter

    PubMed Central

    Baglieri, Jacopo; Beck, Daniel; Vasisht, Nishi; Smith, Corinne J.; Robinson, Colin

    2012-01-01

    The twin-arginine translocation (Tat) system transports folded proteins across bacterial and plant thylakoid membranes. Most current models for the translocation mechanism propose the coalescence of a substrate-binding TatABC complex with a separate TatA complex. In Escherichia coli, TatA complexes are widely believed to form the translocation pore, and the size variation of TatA has been linked to the transport of differently sized substrates. Here, we show that the TatA paralog TatE can substitute for TatA and support translocation of Tat substrates including AmiA, AmiC, and TorA. However, TatE is found as much smaller, discrete complexes. Gel filtration and blue native electrophoresis suggest sizes between ∼50 and 110 kDa, and single-particle processing of electron micrographs gives size estimates of 70–90 kDa. Three-dimensional models of the two principal TatE complexes show estimated diameters of 6–8 nm and potential clefts or channels of up to 2.5 nm diameter. The ability of TatE to support translocation of the 90-kDa TorA protein suggests alternative translocation models in which single TatA/E complexes do not contribute the bulk of the translocation channel. The homogeneity of both the TatABC and the TatE complexes further suggests that a discrete Tat translocase can translocate a variety of substrates, presumably through the use of a flexible channel. The presence and possible significance of double- or triple-ring TatE forms is discussed. PMID:22190680

  5. Antigenic profile and localization of Clonorchis sinensis proteins in the course of infection

    PubMed Central

    Kim, Tae Yun; Song, Kye-Yong; Sohn, Woon-Mok; Kang, Shin-Yong

    2001-01-01

    In the course of Clonorchis sinensis infection, antigens presented to the hosts may be in a close relation to growth of the fluke. The antigenic proteins stimulating IgG antibody production were chronologically identified by immunoblot and localized by immunohistochemical staining. In the early stage of infection until 12 weeks post-infection (PI), antigens were proteins with molecular mass larger than 34 kDa which were derived from the tegument, testes and intrauterine eggs. After 20 weeks PI, antigens recognized were 29, 27 and 26 kDa proteins from the intestine, excretory bladder and reproductive organs. It is suggested that the tegumental proteins are the most potent antigens and the excretory-secretory proteins with middle molecular mass of 26-45 kDa contribute to the high level production of antibodies after 20 weeks of the C. sinensis infection. PMID:11775331

  6. The tobacco mosaic virus RNA polymerase complex contains a plant protein related to the RNA-binding subunit of yeast eIF-3.

    PubMed Central

    Osman, T A; Buck, K W

    1997-01-01

    A sucrose density gradient-purified, membrane-bound tobacco mosaic virus (tomato strain L) (TMV-L) RNA polymerase containing endogenous RNA template was efficiently solubilized with sodium taurodeoxycholate. Solubilization resulted in an increase in the synthesis of positive-strand, 6.4-kb genome-length single-stranded RNA (ssRNA) and a decrease in the production of 6.4-kbp double-stranded RNA (dsRNA) to levels close to the limits of detection. The solubilized TMV-L RNA polymerase was purified by chromatography on columns of DEAE-Bio-Gel and High Q. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining showed that purified RNA polymerase preparations consistently contained proteins with molecular masses of 183, 126, 56, 54, and 50 kDa, which were not found in equivalent material from healthy plants. Western blotting showed that the two largest of these proteins are the TMV-L-encoded 183- and 126-kDa replication proteins and that the 56-kDa protein is related to the 54.6-kDa GCD10 protein, the RNA-binding subunit of yeast eIF-3. The 126-, 183-, and 56-kDa proteins were coimmunoaffinity selected by antibodies against the TMV-L 126-kDa protein and by antibodies against the GCD10 protein. Antibody-linked polymerase assays showed that active TMV-L RNA polymerase bound to antibodies against the TMV-L 126-kDa protein and to antibodies against the GCD10 protein. Synthesis of genome-length ssRNA and dsRNA by a template-dependent, membrane-bound RNA polymerase was inhibited by antibodies against the GCD10 protein, and this inhibition was reversed by prior addition of GCD10 protein. PMID:9223501

  7. Purification and characterization of a pilin specific for Brazilian purpuric fever-associated Haemophilus influenzae biogroup aegyptius (H. aegyptius) strains.

    PubMed Central

    Weyant, R S; Bibb, W F; Stephens, D S; Holloway, B P; Moo-Penn, W F; Birkness, K A; Helsel, L O; Mayer, L W

    1990-01-01

    Brazilian purpuric fever (BPF) is a recently described fatal pediatric disease caused by systemic infection with Haemophilus influenzae biogroup aegyptius. Previous studies have shown that all H. influenzae biogroup aegyptius strains isolated from BPF cases and case contacts share several unique phenotypic and genotypic characteristics that differentiate them from other H. influenzae biogroup aegyptius strains isolated from conjunctivitis cases in Brazil. One key characteristic of this BPF clone is reactivity in a BPF-specific monoclonal antibody enzyme-linked immunosorbent assay. We have purified and partially characterized a pilin, referred to as the 25-kilodalton (kDa) protein. Aggregates of this protein contain a heat-labile epitope which is recognized by a monoclonal antibody used in the BPF-specific enzyme-linked immunosorbent assay. The protein has a molecular weight of approximately 25,000, is insoluble in most detergents, and fractionates with outer membrane vesicles after LiCl extraction. Biochemical analysis of the 25-kDa protein shows it to have an amino acid composition similar but not identical to that of the H. influenzae type b pilin. The sequence of 20 N-terminal amino acids of the 25-kDa protein shows almost complete homology with the N terminus of the H. influenzae type b pilin and the types 1 and P pilins of Escherichia coli. Transmission electron microscopic analysis of the purified protein shows the presence of filamentous structures similar in morphology to those of H. influenzae pili. Reactivity between the 25-kDa protein and the BPF-specific monoclonal antibody is demonstrated by Western blotting (immunoblotting) and colloidal gold-enhanced immunoelectron microscopy. Hemadsorption analysis shows that expression of this protein is associated with increases in piliated cells and enhanced binding of these cells to human erythrocytes. These studies indicate that expression of the 25-kDa protein is a characteristic unique to the BPF clone and

  8. [Glutamate-binding membrane proteins from human platelets].

    PubMed

    Gurevich, V S; Popov, Iu G; Gorodinskiĭ, A I; Dambinova, S A

    1991-09-01

    Solubilization of the total membrane fraction of human platelets in a 2% solution of sodium deoxycholate and subsequent affinity chromatography on glutamate agarose resulted in two protein fractions possessing a glutamate-binding activity. As can be evidenced from radioligand binding data, the first fraction contains two types of binding sites (Kd1 = 1 microM, Bmax 1 = 100 pmol/mg of protein; Kd2 = 9.3 microMm Bmax2 = 395 pmol/mg of protein). The second fraction has only one type of binding sites (Kd = 1 microM, Bmax = = 110 pmol/mg of protein). SDS-PAAG electrophoresis revealed the presence in the first fraction of proteins with Mr of 14, 24, 56 and 155 kDa, whereas the second fraction was found to contain 14, 46, 71 and 155 kDa proteins. Solid phase immunoenzymatic analysis using poly- and monoclonal specific antibodies against mammalian brain glutamate-binding proteins revealed a marked immunochemical similarity of the isolated protein fractions with human brain synaptic membrane glutamate-binding proteins.

  9. Adhesive proteins of stalked and acorn barnacles display homology with low sequence similarities.

    PubMed

    Jonker, Jaimie-Leigh; Abram, Florence; Pires, Elisabete; Varela Coelho, Ana; Grunwald, Ingo; Power, Anne Marie

    2014-01-01

    Barnacle adhesion underwater is an important phenomenon to understand for the prevention of biofouling and potential biotechnological innovations, yet so far, identifying what makes barnacle glue proteins 'sticky' has proved elusive. Examination of a broad range of species within the barnacles may be instructive to identify conserved adhesive domains. We add to extensive information from the acorn barnacles (order Sessilia) by providing the first protein analysis of a stalked barnacle adhesive, Lepas anatifera (order Lepadiformes). It was possible to separate the L. anatifera adhesive into at least 10 protein bands using SDS-PAGE. Intense bands were present at approximately 30, 70, 90 and 110 kilodaltons (kDa). Mass spectrometry for protein identification was followed by de novo sequencing which detected 52 peptides of 7-16 amino acids in length. None of the peptides matched published or unpublished transcriptome sequences, but some amino acid sequence similarity was apparent between L. anatifera and closely-related Dosima fascicularis. Antibodies against two acorn barnacle proteins (ab-cp-52k and ab-cp-68k) showed cross-reactivity in the adhesive glands of L. anatifera. We also analysed the similarity of adhesive proteins across several barnacle taxa, including Pollicipes pollicipes (a stalked barnacle in the order Scalpelliformes). Sequence alignment of published expressed sequence tags clearly indicated that P. pollicipes possesses homologues for the 19 kDa and 100 kDa proteins in acorn barnacles. Homology aside, sequence similarity in amino acid and gene sequences tended to decline as taxonomic distance increased, with minimum similarities of 18-26%, depending on the gene. The results indicate that some adhesive proteins (e.g. 100 kDa) are more conserved within barnacles than others (20 kDa).

  10. A de novo designed 11 kDa polypeptide: model for amyloidogenic intrinsically disordered proteins.

    PubMed

    Topilina, Natalya I; Ermolenkov, Vladimir V; Sikirzhytski, Vitali; Higashiya, Seiichiro; Lednev, Igor K; Welch, John T

    2010-07-01

    A de novo polypeptide GH(6)[(GA)(3)GY(GA)(3)GE](8)GAH(6) (YE8) has a significant number of identical weakly interacting beta-strands with the turns and termini functionalized by charged amino acids to control polypeptide folding and aggregation. YE8 exists in a soluble, disordered form at neutral pH but is responsive to changes in pH and ionic strength. The evolution of YE8 secondary structure has been successfully quantified during all stages of polypeptide fibrillation by deep UV resonance Raman (DUVRR) spectroscopy combined with other morphological, structural, spectral, and tinctorial characterization. The YE8 folding kinetics at pH 3.5 are strongly dependent on polypeptide concentration with a lag phase that can be eliminated by seeding with a solution of folded fibrillar YE8. The lag phase of polypeptide folding is concentration dependent leading to the conclusion that beta-sheet folding of the 11-kDa amyloidogenic polypeptide is completely aggregation driven.

  11. S-adenosyl methionine regulates calcium channels and inhibits uterine smooth muscle contraction in rats with infectious premature delivery through the transient receptor protein 3/protein kinase Cβ/C-kinase-activated protein phosphatase-1 inhibitor of 17 kDa signaling pathway

    PubMed Central

    Ge, Jing; Han, Tao; Li, Xiaoqiu; Shan, Lili; Zhang, Jinhuan; Hong, Yan; Xia, Yanqiu; Wang, Jun; Hou, Mingxiao

    2018-01-01

    The aim of the present study was to investigate the effects of S-adenosyl methionine (SAMe) on infectious premature inflammatory factors and uterine contraction, and to further explore its mechanism of action via the transient receptor protein 3 (TRPC3)/protein kinase Cβ (PKCβ)/C-kinase-activated protein phosphatase-1 inhibitor of 17 kDa (CPI-17) signaling pathway, following intervention by a TRPC3 inhibitor. A rat model of premature delivery induced by lipopolysaccharide (LPS) was established. Following treatment with SAMe and inhibiting TRPC3 expression, rat serum and uterus were isolated. Hematoxylin and eosin staining was used to observe the histopathological changes in the uterus. Uterine muscle strips in vitro were selected to measure the changes in muscle tension. ELISA was utilized to measure the changes in serum inflammatory factor and oxidative stress indexes. Immunohistochemistry, western blot assay and reverse transcription-quantitative polymerase chain reaction were applied to detect calcium channel protein expression in the uterus. Western blot analysis was employed to measure the expression of TRPC3/PKCβ/CPI-17 signaling pathway-related proteins. TRPC3 was highly expressed in the uterus of rat models of premature delivery induced by LPS. Following treatment with SAMe, inflammatory cell infiltration markedly reduced in the uterus and the tension of in vitro uterine muscle strips significantly decreased. SAMe treatment suppressed inflammatory reaction and oxidative stress, and diminished L-type and T-type calcium channel protein expression. TRPC3/PKCβ/CPI-17 signaling pathway-related protein expression was also reduced. When TRPC3 expression was suppressed, the effects of SAMe against inflammation and oxidative stress were diminished. TRPC3/PKCβ/CPI-17 signaling pathway-related protein expression significantly increased. SAMe was able to reduce inflammatory reaction and oxidative stress in the uterus of rat model of infectious premature delivery

  12. Characterization of the proteins comprising the integral matrix of Strongylocentrotus purpuratus embryonic spicules

    NASA Technical Reports Server (NTRS)

    Killian, C. E.; Wilt, F. H.

    1996-01-01

    In the present study, we enumerate and characterize the proteins that comprise the integral spicule matrix of the Strongylocentrotus purpuratus embryo. Two-dimensional gel electrophoresis of [35S]methionine radiolabeled spicule matrix proteins reveals that there are 12 strongly radiolabeled spicule matrix proteins and approximately three dozen less strongly radiolabeled spicule matrix proteins. The majority of the proteins have acidic isoelectric points; however, there are several spicule matrix proteins that have more alkaline isoelectric points. Western blotting analysis indicates that SM50 is the spicule matrix protein with the most alkaline isoelectric point. In addition, two distinct SM30 proteins are identified in embryonic spicules, and they have apparent molecular masses of approximately 43 and 46 kDa. Comparisons between embryonic spicule matrix proteins and adult spine integral matrix proteins suggest that the embryonic 43-kDa SM30 protein is an embryonic isoform of SM30. An adult 49-kDa spine matrix protein is also identified as a possible adult isoform of SM30. Analysis of the SM30 amino acid sequences indicates that a portion of SM30 proteins is very similar to the carbohydrate recognition domain of C-type lectin proteins.

  13. Monoclonal Antibody Analysis and Insecticidal Spectrum of Three Types of Lepidopteran-Specific Insecticidal Crystal Proteins of Bacillus thuringiensis

    PubMed Central

    Höfte, Herman; Van Rie, Jeroen; Jansens, Stefan; Van Houtven, Annemie; Vanderbruggen, Hilde; Vaeck, Mark

    1988-01-01

    We have investigated the protein composition and the insecticidal spectrum of crystals of 29 Bacillus thuringiensis strains active against lepidopteran larvae. All crystals contained proteins of 130 to 140 kilodaltons (kDa) which could be grouped into three types by the molecular weight of the protoxin and the trypsin-activated core fragment. Proteins of the three types showed a characteristic insecticidal spectrum when tested against five lepidopteran species. Type A crystal proteins were protoxins of 130 or 133 kDa, which were processed into 60-kDa toxins by trypsin. Several genes encoding crystal proteins of this type have been cloned and sequenced earlier. They are highly conserved in the N-terminal half of the toxic fragment and were previously classified in three subtypes (the 4.5-, 5.3-, and 6.6-kilobase subtypes) based on the restriction map of their genes. The present study shows that different proteins of these three subtypes were equally toxic against Manduca sexta and Pieris brassicae and had no detectable activity against Spodoptera littoralis. However, the 4.5-, 5.3-, and 6.6-kilobase subtypes differed in their toxicity against Heliothis virescens and Mamestra brassicae. Type B crystal proteins consisted of 140-kDa protoxins with a 55-kDa tryptic core fragment. These were only active against one of the five insect species tested (P. brassicae). The protoxin and the trypsin-activated toxin of type C were 135- and 63-kDa proteins, respectively. Proteins of this type were associated with high toxicity against S. littoralis and M. brassicae. A panel of 35 monoclonal antibodies was used to compare the structural characteristics of crystal proteins of the three different types and subtypes. Each type of protein could be associated with a typical epitope structure, indicating an unambiguous correlation between antigenic structure and insect specificity. Images PMID:16347711

  14. ABA, porphyrins and plant TSPO-related protein.

    PubMed

    Guillaumot, Damien; Guillon, Stéphanie; Morsomme, Pierre; Batoko, Henri

    2009-11-01

    We have shown that, unexpectedly, AtTSPO (Arabidopsis thaliana TSPO-related protein) is an endoplasmic reticulum and Golgi-localized membrane protein in plant cells.(1) This localization contrasts with that of mammalian 18-kDa translocator protein (at least for the mostly studied isoform, 18-kDa TSPO), a mitochondrial outer membrane protein (reviewed in ref. 2). Whereas the potential functions of 18-kDa TSPO are well documented, involved mainly in mitochondrial physiology,(2) and its interest as drugs target is been explored,(3) the roles of TSPO-related proteins in plant growth and development are yet to be specified. AtTSPO is expressed in dry seeds and can be induced in vegetative tissues by osmotic and salt stress or abscisic acid (ABA) treatment. Moreover, it was shown that the ABA-dependent induction is transient, and that boosting tetrapyrroles biosynthesis through 5-aminolevulinic acid (ALA) feeding enhanced downregulation of AtTSPO, suggesting an inherent post-translational regulation mechanism also involving ABA and likely porphyrins. We present additional evidence that ABA can help stabilize constitutively expressed AtTSPO and that ALA feeding to knockout mutant seeds, induces substantial germination delay. Here we discuss the possible link between ABA and tetrapyrroles in AtTSPO expression and post-translational regulation.

  15. Cloning and sequencing of a gene encoding a 21-kilodalton outer membrane protein from Bordetella avium and expression of the gene in Salmonella typhimurium.

    PubMed Central

    Gentry-Weeks, C R; Hultsch, A L; Kelly, S M; Keith, J M; Curtiss, R

    1992-01-01

    Three gene libraries of Bordetella avium 197 DNA were prepared in Escherichia coli LE392 by using the cosmid vectors pCP13 and pYA2329, a derivative of pCP13 specifying spectinomycin resistance. The cosmid libraries were screened with convalescent-phase anti-B. avium turkey sera and polyclonal rabbit antisera against B. avium 197 outer membrane proteins. One E. coli recombinant clone produced a 56-kDa protein which reacted with convalescent-phase serum from a turkey infected with B. avium 197. In addition, five E. coli recombinant clones were identified which produced B. avium outer membrane proteins with molecular masses of 21, 38, 40, 43, and 48 kDa. At least one of these E. coli clones, which encoded the 21-kDa protein, reacted with both convalescent-phase turkey sera and antibody against B. avium 197 outer membrane proteins. The gene for the 21-kDa outer membrane protein was localized by Tn5seq1 mutagenesis, and the nucleotide sequence was determined by dideoxy sequencing. DNA sequence analysis of the 21-kDa protein revealed an open reading frame of 582 bases that resulted in a predicted protein of 194 amino acids. Comparison of the predicted amino acid sequence of the gene encoding the 21-kDa outer membrane protein with protein sequences in the National Biomedical Research Foundation protein sequence data base indicated significant homology to the OmpA proteins of Shigella dysenteriae, Enterobacter aerogenes, E. coli, and Salmonella typhimurium and to Neisseria gonorrhoeae outer membrane protein III, Haemophilus influenzae protein P6, and Pseudomonas aeruginosa porin protein F. The gene (ompA) encoding the B. avium 21-kDa protein hybridized with 4.1-kb DNA fragments from EcoRI-digested, chromosomal DNA of Bordetella pertussis and Bordetella bronchiseptica and with 6.0- and 3.2-kb DNA fragments from EcoRI-digested, chromosomal DNA of B. avium and B. avium-like DNA, respectively. A 6.75-kb DNA fragment encoding the B. avium 21-kDa protein was subcloned into the

  16. Age-Related Decrease in Heat Shock 70-kDa Protein 8 in Cerebrospinal Fluid Is Associated with Increased Oxidative Stress

    PubMed Central

    Loeffler, David A.; Klaver, Andrea C.; Coffey, Mary P.; Aasly, Jan O.; LeWitt, Peter A.

    2016-01-01

    Age-associated declines in protein homeostasis mechanisms (“proteostasis”) are thought to contribute to age-related neurodegenerative disorders. The increased oxidative stress which occurs with aging can activate a key proteostatic process, chaperone-mediated autophagy. This study investigated age-related alteration in cerebrospinal fluid (CSF) concentrations of heat shock 70-kDa protein 8 (HSPA8), a molecular chaperone involved in proteostatic mechanisms including chaperone-mediated autophagy, and its associations with indicators of oxidative stress (8-hydroxy-2′-deoxyguanosine [8-OHdG] and 8-isoprostane) and total anti-oxidant capacity. We examined correlations between age, HSPA8, 8-OHdG, 8-isoprostane, and total antioxidant capacity (TAC) in CSF samples from 34 healthy subjects ranging from 20 to 75 years of age. Age was negatively associated with HSPA8 (ρ = –0.47; p = 0.005). An age-related increase in oxidative stress was indicated by a positive association between age and 8-OHdG (ρ = 0.61; p = 0.0001). HSPA8 was moderately negatively associated with 8-OHdG (ρ = –0.58; p = 0.0004). Age and HSPA8 were weakly associated with 8-isoprostane and TAC (range of ρ values: –0.15 to 0.16). Our findings in this exploratory study suggest that during healthy aging, CSF HSPA8 may decrease, perhaps due in part to an increase in oxidative stress. Our results also suggest that 8-OHdG may be more sensitive than 8-isoprostane for measuring oxidative stress in CSF. Further studies are indicated to determine if our findings can be replicated with a larger cohort, and if the age-related decrease in HSPA8 in CSF is reflected by a similar change in the brain. PMID:27507943

  17. Polar distribution of annexin-like proteins during phytochrome-mediated initiation and growth of rhizoids in the ferns Dryopteris and Anemia

    NASA Technical Reports Server (NTRS)

    Clark, G. B.; Turnwald, S.; Tirlapur, U. K.; Haas, C. J.; von der Mark, K.; Roux, S. J.; Scheuerlein, R.

    1995-01-01

    Although the calcium requirement of phytochrome-mediated fern spore germination and early rhizoid growth is well established, the calcium-binding proteins that serve as transducers for these responses are not known. Here we report the presence of annexin-like proteins in germinating spores of Dryopteris filix-mas (L.) Schott and Anemia phyllitidis (L.) Sw. and evidence that they may be important participants in early photomorphogenic changes in gametophytes. Immunolocalization and immunoblot assays of these proteins were carried out using polyclonal antibodies raised either against a 35-kDa annexin-like protein from pea or against anchorin CII from chicken. Western-blot analysis showed that crude protein extracts obtained from both species after red-light treatment contained two cross-reactive protein bands with molecular weights around 70 kDa. These proteins were annexin-like in that they bound to a phosphatidylserine affinity column in a calcium-dependent fashion. Using this column, two protein bands around 70 kDa, i.e. 67 and 73 kDa, were partially purified together with proteins at 36 kDa and a doublet at 54 kDa. Proteins of these latter molecular weights are suggested to be members of the annexin family, but no cross-reactivity could be found between these and the two antibodies used in our investigations. Immunodetectable levels of these proteins were observed only after light-mediated induction of spore germination. Imaging of the immuno-localization patterns observed with both antibodies showed that the annexin-like proteins are concentrated at the extreme tips of the rhizoids in D. filix-mas and A. phyllitidis during rhizoid initiation and all stages of elongation. We suggest that these proteins may play a major role in the tip-oriented exocytosis events that are critical for the initiation and growth of fern rhizoids.

  18. Polar distribution of annexin-like proteins during phytochrome-mediated initiation and growth of rhizoids in the ferns Dryopteris and Anemia.

    PubMed

    Clark, G B; Turnwald, S; Tirlapur, U K; Haas, C J; von der Mark, K; Roux, S J; Scheuerlein, R

    1995-01-01

    Although the calcium requirement of phytochrome-mediated fern spore germination and early rhizoid growth is well established, the calcium-binding proteins that serve as transducers for these responses are not known. Here we report the presence of annexin-like proteins in germinating spores of Dryopteris filix-mas (L.) Schott and Anemia phyllitidis (L.) Sw. and evidence that they may be important participants in early photomorphogenic changes in gametophytes. Immunolocalization and immunoblot assays of these proteins were carried out using polyclonal antibodies raised either against a 35-kDa annexin-like protein from pea or against anchorin CII from chicken. Western-blot analysis showed that crude protein extracts obtained from both species after red-light treatment contained two cross-reactive protein bands with molecular weights around 70 kDa. These proteins were annexin-like in that they bound to a phosphatidylserine affinity column in a calcium-dependent fashion. Using this column, two protein bands around 70 kDa, i.e. 67 and 73 kDa, were partially purified together with proteins at 36 kDa and a doublet at 54 kDa. Proteins of these latter molecular weights are suggested to be members of the annexin family, but no cross-reactivity could be found between these and the two antibodies used in our investigations. Immunodetectable levels of these proteins were observed only after light-mediated induction of spore germination. Imaging of the immuno-localization patterns observed with both antibodies showed that the annexin-like proteins are concentrated at the extreme tips of the rhizoids in D. filix-mas and A. phyllitidis during rhizoid initiation and all stages of elongation. We suggest that these proteins may play a major role in the tip-oriented exocytosis events that are critical for the initiation and growth of fern rhizoids.

  19. Casein kinase II protein kinase is bound to lamina-matrix and phosphorylates lamin-like protein in isolated pea nuclei

    NASA Technical Reports Server (NTRS)

    Li, H.; Roux, S. J.

    1992-01-01

    A casein kinase II (CK II)-like protein kinase was identified and partially isolated from a purified envelope-matrix fraction of pea (Pisum sativum L.) nuclei. When [gamma-32P]ATP was directly added to the envelope-matrix preparation, the three most heavily labeled protein bands had molecular masses near 71, 48, and 46 kDa. Protein kinases were removed from the preparation by sequential extraction with Triton X-100, EGTA, 0.3 M NaCl, and a pH 10.5 buffer, but an active kinase still remained bound to the remaining lamina-matrix fraction after these treatments. This kinase had properties resembling CK II kinases previously characterized from animal and plant sources: it preferred casein as an artificial substrate, could use GTP as efficiently as ATP as the phosphoryl donor, was stimulated by spermine, was calcium independent, and had a catalytic subunit of 36 kDa. Some animal and plant CK II kinases have regulatory subunits near 29 kDa, and a lamina-matrix-bound protein of this molecular mass was recognized on immunoblot by anti-Drosophila CK II polyclonal antibodies. Also found associated with the envelope-matrix fraction of pea nuclei were p34cdc2-like and Ca(2+)-dependent protein kinases, but their properties could not account for the protein kinase activity bound to the lamina. The 71-kDa substrate of the CK II-like kinase was lamin A-like, both in its molecular mass and in its cross-reactivity with anti-intermediate filament antibodies. Lamin phosphorylation is considered a crucial early step in the entry of cells into mitosis, so lamina-bound CK II kinases may be important control points for cellular proliferation.

  20. An intron-containing glycoside hydrolase family 9 cellulase gene encodes the dominant 90 kDa component of the cellulosome of the anaerobic fungus Piromyces sp. strain E2.

    PubMed Central

    Steenbakkers, Peter J M; Ubhayasekera, Wimal; Goossen, Harry J A M; van Lierop, Erik M H M; van der Drift, Chris; Vogels, Godfried D; Mowbray, Sherry L; Op den Camp, Huub J M

    2002-01-01

    The cellulosome produced by Piromyces sp. strain E2 during growth on filter paper was purified by using an optimized cellulose-affinity method consisting of steps of EDTA washing of the cellulose-bound protein followed by elution with water. Three dominant proteins were identified in the cellulosome preparation, with molecular masses of 55, 80 and 90 kDa. Treatment of cellulose-bound cellulosome with a number of denaturing agents was also tested. Incubation with 0.5% (w/v) SDS or 8 M urea released most cellulosomal proteins, while leaving the greater fraction of the 80, 90 and 170 kDa components. To investigate the major 90 kDa cellulosome protein further, the corresponding gene, cel9A, was isolated, using immunoscreening and N-terminal sequencing. Inspection of the cel9A genomic organization revealed the presence of four introns, allowing the construction of a consensus for introns in anaerobic fungi. The 2800 bp cDNA clone contained an open reading frame of 2334 bp encoding a 757-residue extracellular protein. Cel9A includes a 445-residue glycoside hydrolase family 9 catalytic domain, and so is the first fungal representative of this large family. Both modelling of the catalytic domain as well as the activity measured with low level expression in Escherichia coli indicated that Cel9A is an endoglucanase. The catalytic domain is succeeded by a putative beta-sheet module of 160 amino acids with unknown function, followed by a threonine-rich linker and three fungal docking domains. Homology modelling of the Cel9A dockerins suggested that the cysteine residues present are all involved in disulphide bridges. The results presented here are used to discuss evolution of glycoside hydrolase family 9 enzymes. PMID:12071852

  1. Genetic Diversity and Natural Selection in 42 kDa Region of Plasmodium vivax Merozoite Surface Protein-1 from China-Myanmar Endemic Border.

    PubMed

    Zhou, Xia; Tambo, Ernest; Su, Jing; Fang, Qiang; Ruan, Wei; Chen, Jun-Hu; Yin, Ming-Bo; Zhou, Xiao-Nong

    2017-10-01

    Plasmodium vivax merozoite surface protein-1 (PvMSP1) gene codes for a major malaria vaccine candidate antigen. However, its polymorphic nature represents an obstacle to the design of a protective vaccine. In this study, we analyzed the genetic polymorphism and natural selection of the C-terminal 42 kDa fragment within PvMSP1 gene (Pv MSP142) from 77 P. vivax isolates, collected from imported cases of China-Myanmar border (CMB) areas in Yunnan province and the inland cases from Anhui, Yunnan, and Zhejiang province in China during 2009-2012. Totally, 41 haplotypes were identified and 30 of them were new haplotypes. The differences between the rates of non-synonymous and synonymous mutations suggest that PvMSP142 has evolved under natural selection, and a high selective pressure preferentially acted on regions identified of PvMSP133. Our results also demonstrated that PvMSP142 of P. vivax isolates collected on China-Myanmar border areas display higher genetic polymorphisms than those collected from inland of China. Such results have significant implications for understanding the dynamic of the P. vivax population and may be useful information towards China malaria elimination campaign strategies.

  2. LAMP proteins account for the maturation delay during the establishment of the Coxiella burnetii-containing vacuole.

    PubMed

    Schulze-Luehrmann, Jan; Eckart, Rita A; Ölke, Martha; Saftig, Paul; Liebler-Tenorio, Elisabeth; Lührmann, Anja

    2016-02-01

    The obligate intracellular pathogen Coxiella burnetii replicates in a large phagolysosomal-like vacuole. Currently, both host and bacterial factors required for creating this replicative parasitophorous C. burnetii-containing vacuole (PV) are poorly defined. Here, we assessed the contributions of the most abundant proteins of the lysosomal membrane, LAMP-1 and LAMP-2, to the establishment and maintenance of the PV. Whereas these proteins were not critical for uptake of C. burnetii, they influenced the intracellular replication of C. burnetii. In LAMP-1/2 double-deficient fibroblasts as well as in LAMP-1/2 knock-down cells, C. burnetii establishes a significantly smaller, yet faster maturing vacuole, which harboured more bacteria. The accelerated maturation of PVs in LAMP double-deficient fibroblasts, which was partially or fully reversed by ectopic expression of LAMP-1 or LAMP-2, respectively, was characterized by an increased fusion rate with endosomes, lysosomes and bead-containing phagosomes, but not by different fusion kinetics with autophagy vesicles. These findings establish that LAMP proteins are critical for the maturation delay of PVs. Unexpectedly, neither the creation of the spacious vacuole nor the delay in maturation was found to be prerequisites for the intracellular replication of C. burnetii. © 2015 John Wiley & Sons Ltd.

  3. A novel 53-kDa nodulin of the symbiosome membrane of soybean nodules, controlled by Bradyrhizobium japonicum.

    PubMed

    Winzer, T; Bairl, A; Linder, M; Linder, D; Werner, D; Müller, P

    1999-03-01

    A nodule-specific 53-kDa protein (GmNOD53b) of the symbiosome membrane from soybean was isolated and its LysC digestion products were microsequenced. cDNA clones of this novel nodulin, obtained from cDNA library screening with an RT-PCR (reverse-transcriptase polymerase chain reaction)-generated hybridization probe exhibited no homology to proteins identified so far. The expression of GmNOD53b coincides with the onset of nitrogen fixation. Therefore, it is a late nodulin. Among other changes, the GmNOD53b is significantly reduced in nodules infected with the Bradyrhizobium japonicum mutant 184 on the protein level as well as on the level of mRNA expression, compared with the wild-type infected nodules. The reduction of GmNOD53b mRNA is related to an inactivation of the sipF gene in B. japonicum 184, coding for a functionally active signal peptidase.

  4. Adhesive Proteins of Stalked and Acorn Barnacles Display Homology with Low Sequence Similarities

    PubMed Central

    Jonker, Jaimie-Leigh; Abram, Florence; Pires, Elisabete; Varela Coelho, Ana; Grunwald, Ingo; Power, Anne Marie

    2014-01-01

    Barnacle adhesion underwater is an important phenomenon to understand for the prevention of biofouling and potential biotechnological innovations, yet so far, identifying what makes barnacle glue proteins ‘sticky’ has proved elusive. Examination of a broad range of species within the barnacles may be instructive to identify conserved adhesive domains. We add to extensive information from the acorn barnacles (order Sessilia) by providing the first protein analysis of a stalked barnacle adhesive, Lepas anatifera (order Lepadiformes). It was possible to separate the L. anatifera adhesive into at least 10 protein bands using SDS-PAGE. Intense bands were present at approximately 30, 70, 90 and 110 kilodaltons (kDa). Mass spectrometry for protein identification was followed by de novo sequencing which detected 52 peptides of 7–16 amino acids in length. None of the peptides matched published or unpublished transcriptome sequences, but some amino acid sequence similarity was apparent between L. anatifera and closely-related Dosima fascicularis. Antibodies against two acorn barnacle proteins (ab-cp-52k and ab-cp-68k) showed cross-reactivity in the adhesive glands of L. anatifera. We also analysed the similarity of adhesive proteins across several barnacle taxa, including Pollicipes pollicipes (a stalked barnacle in the order Scalpelliformes). Sequence alignment of published expressed sequence tags clearly indicated that P. pollicipes possesses homologues for the 19 kDa and 100 kDa proteins in acorn barnacles. Homology aside, sequence similarity in amino acid and gene sequences tended to decline as taxonomic distance increased, with minimum similarities of 18–26%, depending on the gene. The results indicate that some adhesive proteins (e.g. 100 kDa) are more conserved within barnacles than others (20 kDa). PMID:25295513

  5. Rapid auxin-induced nitric oxide accumulation and subsequent tyrosine nitration of proteins during adventitious root formation in sunflower hypocotyls

    PubMed Central

    Yadav, Sunita; David, Anisha; Baluška, František; Bhatla, Satish C.

    2013-01-01

    Using NO specific probe (MNIP-Cu), rapid nitric oxide (NO) accumulation as a response to auxin (IAA) treatment has been observed in the protoplasts from the hypocotyls of sunflower seedlings (Helianthus annuus L.). Incubation of protoplasts in presence of NPA (auxin efflux blocker) and PTIO (NO scavenger) leads to significant reduction in NO accumulation, indicating that NO signals represent an early signaling event during auxin-induced response. A surge in NO production has also been demonstrated in whole hypocotyl explants showing adventitious root (AR) development. Evidence of tyrosine nitration of cytosolic proteins as a consequence of NO accumulation has been provided by western blot analysis and immunolocalization in the sections of AR producing hypocotyl segments. Most abundant anti-nitrotyrosine labeling is evident in proteins ranging from 25–80 kDa. Tyrosine nitration of a particular protein (25 kDa) is completely absent in presence of NPA (which suppresses AR formation). Similar lack of tyrosine nitration of this protein is also evident in other conditions which do not allow AR differentiation. Immunofluorescent localization experiments have revealed that non-inductive treatments (such as PTIO) for AR develpoment from hypocotyl segments coincide with symplastic and apoplastic localization of tyrosine nitrated proteins in the xylem elements, in contrast with negligible (and mainly apoplastic) nitration of proteins in the interfascicular cells and phloem elements. Application of NPA does not affect tyrosine nitration of proteins even in the presence of an external source of NO (SNP). Tyrosine nitrated proteins are abundant around the nuclei in the actively dividing cells of the root primordium. Thus, NO-modulated rapid response to IAA treatment through differential distribution of tyrosine nitrated proteins is evident as an inherent aspect of the AR development. PMID:23299324

  6. Expression of Clara cell 10-kDa protein and trefoil factor family 1 in patients with chronic rhinosinusitis and nasal polyps

    PubMed Central

    Wang, Yuanyuan; Wang, Zong-Feng; Zhang, Zhili; Su, Yi

    2018-01-01

    The current study measured the expression of Clara cell 10-kDa protein (CC10) and trefoil factor family 1 (TFF1) in the sinus mucosa of patients exhibiting chronic rhinosinusitis (CRS) and nasal polyps (NP). CC10 and TFF1 expression in the sinus mucosa of the control group and patients with CRS and NP was determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR), western blotting and immunohistochemistry. The correlation between CC10 and TFF1 expression was further analyzed using Spearman's correlation analysis. The expression of TFF1 was significantly increased in the sinus mucosa of patients with CRS and NP, whereas CC10 expression was significantly decreased compared with controls. Spearman's correlation analysis identified a negative correlation between CC10 and TFF1 expression in the sinus mucosa of patients with CRS and NP. The results of immunohistochemistry and RT-qPCR were consistent with each other. Hematoxylin and eosin staining revealed notable lesions in the mucous membranes, goblet cells and cilia of sinus mucosa samples from patients with CRS and NP. The negative correlation between CC10 and TFF1 expression during the progression of CRS and NP suggest that CC10 and TFF1 may serve important roles in its pathogenesis. PMID:29456658

  7. Hyaluronan 35kDa treatment protects mice from Citrobacter rodentium infection and induces epithelial tight junction protein ZO-1 in vivo.

    PubMed

    Kim, Yeojung; Kessler, Sean P; Obery, Dana R; Homer, Craig R; McDonald, Christine; de la Motte, Carol A

    2017-10-01

    Maintaining a healthy intestinal barrier, the primary physical barrier between intestinal microbiota and the underlying lamina propria, is critical for optimal health. Epithelial integrity is essential for the prevention of the entrance of luminal contents, such as bacteria and their products, through the large intestinal barrier. In this study, we investigated the protective functions of biosynthetic, specific sized, hyaluronan around 35kDa (HA35) on intestinal epithelium in healthy mice, as well as mice infected Citrobacter rodentium, an established model that mimics infection with a serious human pathogen, enteropathogenic E. coli (EPEC). Our results reveal that treatment with HA35 protects mice from Citrobacter infection and enhances the epithelial barrier function. In particular, we have found that HA35 induces the expression of tight junction protein zonula occludens (ZO)-1 in both healthy and Citrobacter infected mice, as demonstrated by immunoflurorescence and Western blot analyses. Furthermore, we determined that HA35 treatment enhances ZO-1 expression and reduces intestinal permeability at the early stages of dextran sulfate sodium (DSS)-induced colitis in mice. Together, our data demonstrate that the expression and functionality of tight junctions, are increased by HA35 treatment, suggesting a novel mechanism for the protection from Citrobacter infection. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Cytoskeleton in trichomonads: I. Immunological and biochemical comparative study of costal proteins in the genus Tritrichomonas.

    PubMed

    Viscogliosi, E; Brugerolle, G

    1993-05-28

    Proteins of the whole cytoskeleton fraction obtained by Triton X-100 action on several Tritrichomonas species have been analyzed by gel electrophoresis. In addition to tubulins, several major protein components with molecular weights between 100 and 150 kDa were separated and presumably represent costal proteins. The partial purification of the costae from the whole cytoskeleton fraction of Tritrichomonas foetus treated with 0.3 M KI confirmed the presence of costal proteins in the 100-150 kDa zone. Costa fibres could be solubilized in 8 M urea. These characteristics indicate that costal proteins may represent a novel class of striated root proteins. A library of 7 monoclonal antibodies (MAbs) raised in mice immunized with the whole cytoskeleton fraction of Tritrichomonas foetus labelled the costa by immunofluorescence and recognize five polypeptides at 135,127,114, 88 and 47 kDa by immunoblotting. Two of these MAbs cross-react by immunofluorescence and immunoblotting with the three other Tritrichomonas species tested, i.e. T. mobilensis, T. augusta, T. muris. However, these 7 MAbs do not show immunological cross-reactivity with other trichomonad genera indicating that the costae are not identical in their biochemical composition; this corresponds to the differences observed in their respective fine structure. Nonetheless, a polyclonal antibody produced against the 118 kDa protein of the costa of Trichomonas vaginalis also labels a 118 kDa protein and the costa by IF in Tritrichomonas species indicating common epitopes. Copyright © 1993 Gustav Fischer Verlag · Stuttgart · Jena · New York. Published by Elsevier GmbH.. All rights reserved.

  9. Identification of a movement protein of Mirafiori lettuce big-vein ophiovirus.

    PubMed

    Hiraguri, Akihiro; Ueki, Shoko; Kondo, Hideki; Nomiyama, Koji; Shimizu, Takumi; Ichiki-Uehara, Tamaki; Omura, Toshihiro; Sasaki, Nobumitsu; Nyunoya, Hiroshi; Sasaya, Takahide

    2013-05-01

    Mirafiori lettuce big-vein virus (MiLBVV) is a member of the genus Ophiovirus, which is a segmented negative-stranded RNA virus. In microprojectile bombardment experiments to identify a movement protein (MP) gene of ophioviruses that can trans-complement intercellular movement of an MP-deficient heterologous virus, a plasmid containing an infectious clone of a tomato mosaic virus (ToMV) derivative expressing the GFP was co-bombarded with plasmids containing one of three genes from MiLBVV RNAs 1, 2 and 4 onto Nicotiana benthamiana. Intercellular movement of the movement-defective ToMV was restored by co-expression of the 55 kDa protein gene, but not with the two other genes. Transient expression in epidermal cells of N. benthamiana and onion showed that the 55 kDa protein with GFP was localized on the plasmodesmata. The 55 kDa protein encoded in the MiLBVV RNA2 can function as an MP of the virus. This report is the first to describe an ophiovirus MP.

  10. Identification of extracellular surface-layer associated proteins in Lactobacillus acidophilus NCFM

    PubMed Central

    Johnson, Brant; Selle, Kurt; O’Flaherty, Sarah; Goh, Yong Jun

    2013-01-01

    Bacterial surface (S-) layers are crystalline arrays of self-assembling, proteinaceous subunits called S-layer proteins (Slps), with molecular masses ranging from 40 to 200 kDa. The S-layer-forming bacterium Lactobacillus acidophilus NCFM expresses three major Slps: SlpA (46 kDa), SlpB (47 kDa) and SlpX (51 kDa). SlpA has a demonstrated role in adhesion to Caco-2 intestinal epithelial cells in vitro, and has been shown to modulate dendritic cell (DC) and T-cell functionalities with murine DCs. In this study, a modification of a standard lithium chloride S-layer extraction revealed 37 proteins were solubilized from the S-layer wash fraction. Of these, 30 have predicted cleavage sites for secretion, 24 are predicted to be extracellular, six are lipid-anchored, three have N-terminal hydrophobic membrane spanning regions and four are intracellular, potentially moonlighting proteins. Some of these proteins, designated S-layer associated proteins (SLAPs), may be loosely associated with or embedded within the bacterial S-layer complex. Lba-1029, a putative SLAP gene, was deleted from the chromosome of L. acidophilus. Phenotypic characterization of the deletion mutant demonstrated that the SLAP LBA1029 contributes to a pro-inflammatory TNF-α response from murine DCs. This study identified extracellular proteins and putative SLAPs of L. acidophilus NCFM using LC-MS/MS. SLAPs appear to impart important surface display features and immunological properties to microbes that are coated by S-layers. PMID:24002751

  11. TRIM25 Enhances the Antiviral Action of Zinc-Finger Antiviral Protein (ZAP)

    PubMed Central

    Lau, Zerlina; Cheung, Pamela; Schneider, William M.; Bozzacco, Leonia; Buehler, Eugen; Takaoka, Akinori; Rice, Charles M.; Felsenfeld, Dan P.; MacDonald, Margaret R.

    2017-01-01

    The host factor and interferon (IFN)-stimulated gene (ISG) product, zinc-finger antiviral protein (ZAP), inhibits a number of diverse viruses by usurping and intersecting with multiple cellular pathways. To elucidate its antiviral mechanism, we perform a loss-of-function genome-wide RNAi screen to identify cellular cofactors required for ZAP antiviral activity against the prototype alphavirus, Sindbis virus (SINV). In order to exclude off-target effects, we carry out stringent confirmatory assays to verify the top hits. Important ZAP-liaising partners identified include proteins involved in membrane ion permeability, type I IFN signaling, and post-translational protein modification. The factor contributing most to the antiviral function of ZAP is TRIM25, an E3 ubiquitin and ISG15 ligase. We demonstrate here that TRIM25 interacts with ZAP through the SPRY domain, and TRIM25 mutants lacking the RING or coiled coil domain fail to stimulate ZAP’s antiviral activity, suggesting that both TRIM25 ligase activity and its ability to form oligomers are critical for its cofactor function. TRIM25 increases the modification of both the short and long ZAP isoforms by K48- and K63-linked polyubiquitin, although ubiquitination of ZAP does not directly affect its antiviral activity. However, TRIM25 is critical for ZAP’s ability to inhibit translation of the incoming SINV genome. Taken together, these data uncover TRIM25 as a bona fide ZAP cofactor that leads to increased ZAP modification enhancing its translational inhibition activity. PMID:28060952

  12. TRIM25 Enhances the Antiviral Action of Zinc-Finger Antiviral Protein (ZAP).

    PubMed

    Li, Melody M H; Lau, Zerlina; Cheung, Pamela; Aguilar, Eduardo G; Schneider, William M; Bozzacco, Leonia; Molina, Henrik; Buehler, Eugen; Takaoka, Akinori; Rice, Charles M; Felsenfeld, Dan P; MacDonald, Margaret R

    2017-01-01

    The host factor and interferon (IFN)-stimulated gene (ISG) product, zinc-finger antiviral protein (ZAP), inhibits a number of diverse viruses by usurping and intersecting with multiple cellular pathways. To elucidate its antiviral mechanism, we perform a loss-of-function genome-wide RNAi screen to identify cellular cofactors required for ZAP antiviral activity against the prototype alphavirus, Sindbis virus (SINV). In order to exclude off-target effects, we carry out stringent confirmatory assays to verify the top hits. Important ZAP-liaising partners identified include proteins involved in membrane ion permeability, type I IFN signaling, and post-translational protein modification. The factor contributing most to the antiviral function of ZAP is TRIM25, an E3 ubiquitin and ISG15 ligase. We demonstrate here that TRIM25 interacts with ZAP through the SPRY domain, and TRIM25 mutants lacking the RING or coiled coil domain fail to stimulate ZAP's antiviral activity, suggesting that both TRIM25 ligase activity and its ability to form oligomers are critical for its cofactor function. TRIM25 increases the modification of both the short and long ZAP isoforms by K48- and K63-linked polyubiquitin, although ubiquitination of ZAP does not directly affect its antiviral activity. However, TRIM25 is critical for ZAP's ability to inhibit translation of the incoming SINV genome. Taken together, these data uncover TRIM25 as a bona fide ZAP cofactor that leads to increased ZAP modification enhancing its translational inhibition activity.

  13. Effect of polymer molecular weight on chitosan-protein interaction.

    PubMed

    Bekale, L; Agudelo, D; Tajmir-Riahi, H A

    2015-01-01

    We present a comprehensive study of the interactions between chitosan nanoparticles (15, 100 and 200 kDa with the same degree of deacetylation 90%) and two model proteins, i.e., bovine (BSA) and human serum albumins (HSA), with the aim of correlating chitosan molecular weight (Mw) and the binding affinity of these naturally occurring polymers to protein. The effect of chitosan on the protein secondary structure and the influence of protein complexation on the shape of chitosan nanoparticles are discussed. A combination of multiple spectroscopic methods, transmission electron microscopy (TEM) and thermodynamic analysis were used to assess the polymer-protein complex formation. Results revealed that the three chitosan nanoparticles interact with BSA to form chitosan-BSA complexes, mainly through hydrophobic contacts with the affinity order: 200>100>15 kDa. However, HSA-chitosan complexation is mainly via electrostatic interactions with the stability order: 100>200>15 kDa. Furthermore, the association between polymer and protein causes a partial protein conformational change by a major reduction of α-helix from 63% (free BSA) to 57% (chitosan-BSA) and 57% (free HSA) to 51% (chitosan-HSA). Finally, TEM micrographs clearly revealed that the binding of serum albumins with chitosan nanoparticles induces a significant change in protein morphology and the shape of the polymer. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. The ubiquitin ligase TRIM25 inhibits hepatocellular carcinoma progression by targeting metastasis associated 1 protein.

    PubMed

    Zang, Hong-Liang; Ren, Sheng-Nan; Cao, Hong; Tian, Xiao-Feng

    2017-10-01

    Metastasis associated 1 protein (MTA1) is one of the prime facilitators of metastatic progression in all solid tumors including hepatocellular carcinoma (HCC). However, the underlying regulatory mechanism of MTA1 expression in HCC is not clear. In this study, we evaluated MTA1 transcript and protein expression in HCC and normal hepatic cell lines. The results revealed that MTA1 protein expression had a significantly increase in HCC cell line, HuH6, compared with that in normal hepatic cell line, THLE-2. Determination of protein half-life using cycloheximide (CHX) treatment did not reveal any statistically significant difference in protein turn-over rates between THLE-2 (3.3 ± 0.25 h) and HuH6 (3.6 ± 0.15 h) cell lines. MTA1 protein level was stabilized in THLE-2 cells after treatment with MG-132 to levels similar to those observed in HuH6 cells. Mass spectrometric analysis of FLAG immunoprecipitates of FLAG-MTA1 transfected THLE-2 cells after MG-132 treated revealed candidate ubiquitin ligases that were interacting with MTA1. RNAi-mediated silencing of each prospective ubiquitin ligase in THLE-2 cells indicated that knockdown of TRIM25 resulted in stabilization of MTA1 protein, indicating TRIM25 as a putative E3 ligase for MTA1. Coimmunoprecipitation of FLAG-tagged MTA1, but not IgG, in MG-132 treated and untreated THLE-2 cells cotransfected with either FLAG-MTA1 or Myc-TRIM25 revealed robust polyubiquitinated MTA1, confirming that the TRIM25 is the ubiquitin ligase for MTA1 degradation. Overexpression of TRIM25 in HuH6 and RNAi mediated silencing of TRIM25 in THLE-2 cells inhibited and increased the cell migration and invasion, respectively. Analysis of The Cancer Genome Atlas data for assessment of TRIM25 transcript level and MTA1 protein expression in 25 HCC patients confirmed an inverse correlation between the expression of TRIM25 and MTA1. Cumulatively, our data reveal a novel mechanism of post-translational to regulate MTA1 expression in normal

  15. The effects of thermal treatments on protein profiles of Macrobrachium rosenbergii (giant river prawn)

    NASA Astrophysics Data System (ADS)

    Sockalingam, Komathi; Misnan, Rosmilah; Yadzir, Zailatul Hani Mohd

    2017-05-01

    Prawn allergy is certainly the most frequent cause of allergic reactions in countries where this crustacean is a popular dish of seafood. The aim of this study was to determine the protein profiles of giant river prawn which scientifically known as Macrobrachium rosenbergii. Raw and cooked extracts (boiled, steamed and fried) of prawn samples were prepared and then resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). 27 protein bands between 6 to 207 kDa were detected in the SDS-PAGE gel of raw extracts while boiled, steamed and fried extracts revealed fewer protein bands. Steamed and boiled prawns presented higher numbers of protein bands compared to fried prawn. A prominent heat-resistant band between 32 to 38 kDa was seen in all extracts, might hypothesized to be tropomyosin. Other prominent bands between 17 to 20 kDa were also seen in all treated prawn extracts while bands of 24 to 27 kDa were seen in steamed and boiled prawn extracts. These positions are consistent with the known shellfish allergens myosin light chain, sacroplasmic calcium binding protein and troponin C respectively. Several other heat-sensitive protein bands at various molecular weights were also not detected in boiled, steamed and fried extracts of this prawn. This study showed that M. rosenbergii contains numerous heat-sensitive and heat-resistant proteins, which may play an important role in prawn allergy.

  16. Rift Valley fever virus structural and non-structural proteins: Recombinant protein expression and immunoreactivity against antisera from sheep

    USDA-ARS?s Scientific Manuscript database

    The Rift Valley fever virus (RVFV) encodes structural proteins, nucleoprotein (N), N-terminus glycoprotein (Gn), C-terminus glycoprotein (Gc) and L protein, 78-kDa and non-structural proteins NSm and NSs. Using the baculovirus system we expressed the full-length coding sequence of N, NSs, NSm, Gc an...

  17. Myosin phosphatase and RhoA-activated kinase modulate neurotransmitter release by regulating SNAP-25 of SNARE complex

    PubMed Central

    Sipos, Adrienn; Darula, Zsuzsanna; Bécsi, Bálint; Nagy, Dénes; Iván, Judit; Erdődi, Ferenc

    2017-01-01

    Reversible phosphorylation of neuronal proteins plays an important role in the regulation of neurotransmitter release. Myosin phosphatase holoenzyme (MP) consists of a protein phosphatase-1 (PP1) catalytic subunit (PP1c) and a regulatory subunit, termed myosin phosphatase targeting subunit (MYPT1). The primary function of MP is to regulate the phosphorylation level of contractile proteins; however, recent studies have shown that MP is localized to neurons, and is also involved in the mediation of neuronal processes. Our goal was to investigate the effect of RhoA-activated kinase (ROK) and MP on the phosphorylation of one potential neuronal substrate, the synaptosomal-associated protein of 25 kDa (SNAP-25). SNAP-25 is a member of the SNARE (soluble N-ethylmaleimide sensitive factor attachment protein receptor) complex, along with synaptobrevin and syntaxin, and the primary role of SNAP25 is to mediate vesicle fusion. We showed that MYPT1 interacts with SNAP-25, as revealed by immunoprecipitation and surface plasmon resonance based binding studies. Mass spectrometry analysis and in vitro phosphorylation/dephosphorylation assays demonstrated that ROK phosphorylates, while MP dephosphorylates, SNAP-25 at Thr138. Silencing MYPT1 in B50 neuroblastoma cells increased phosphorylation of SNAP-25 at Thr138. Inhibition of PP1 with tautomycetin increased, whereas inhibition of ROK by H1152, decreased the phosphorylation of SNAP-25 at Thr138 in B50 cells, in cortical synaptosomes, and in brain slices. In response to the transduction of the MP inhibitor, kinase-enhanced PP1 inhibitor (KEPI), into synaptosomes, an increase in phosphorylation of SNAP-25 and a decrease in the extent of neurotransmitter release were detected. The interaction between SNAP-25 and syntaxin increased with decreasing phosphorylation of SNAP-25 at Thr138, upon inhibition of ROK. Our data suggest that ROK/MP play a crucial role in vesicle trafficking, fusion, and neurotransmitter release by oppositely

  18. KU135, a Novel Novobiocin-Derived C-Terminal Inhibitor of the 90-kDa Heat Shock Protein, Exerts Potent Antiproliferative Effects in Human Leukemic Cells

    PubMed Central

    Shelton, Shary N.; Shawgo, Mary E.; Matthews, Shawna B.; Lu, Yuanming; Donnelly, Alison C.; Szabla, Kristen; Tanol, Mehmet; Vielhauer, George A.; Rajewski, Roger A.; Matts, Robert L.; Blagg, Brian S. J.

    2009-01-01

    The 90-kDa heat shock protein (Hsp90) assists in the proper folding of numerous mutated or overexpressed signal transduction proteins that are involved in cancer. Consequently, there is considerable interest in developing chemotherapeutic drugs that specifically disrupt the function of Hsp90. Here, we investigated the extent to which a novel novobiocin-derived C-terminal Hsp90 inhibitor, designated KU135, induced antiproliferative effects in Jurkat T-lymphocytes. The results indicated that KU135 bound directly to Hsp90, caused the degradation of known Hsp90 client proteins, and induced more potent antiproliferative effects than the established N-terminal Hsp90 inhibitor 17-allylamino-demethoxygeldanamycin (17-AAG). Closer examination of the cellular response to KU135 and 17-AAG revealed that only 17-AAG induced a strong up-regulation of Hsp70 and Hsp90. In addition, KU135 caused wild-type cells to undergo G2/M arrest, whereas cells treated with 17-AAG accumulated in G1. Furthermore, KU135 but not 17-AAG was found to be a potent inducer of mitochondria-mediated apoptosis as evidenced, in part, by the fact that cell death was inhibited to a similar extent by Bcl-2/Bcl-xL overexpression or the depletion of apoptotic protease-activating factor-1 (Apaf-1). Together, these data suggest that KU135 inhibits cell proliferation by regulating signaling pathways that are mechanistically different from those targeted by 17-AAG and as such represents a novel opportunity for Hsp90 inhibition. PMID:19741006

  19. Manganese-dependent carboanhydrase activity of photosystem II proteins.

    PubMed

    Shitov, A V; Pobeguts, O V; Smolova, T N; Allakhverdiev, S I; Klimov, V V

    2009-05-01

    Four sources of carbonic anhydrase (CA) activity in submembrane preparations of photosystem II (PS II) isolated from pea leaves were examined. Three of them belong to the hydrophilic proteins of the oxygen-evolving complex of PS II with molecular mass 33 kDa (protein PsbO), 24 kDa (protein PsbP), and 18 kDa (protein PsbQ). The fourth source of CA activity is associated with a pigment-protein complex of PS II after removing three hydrophilic proteins by salt treatment. Except for protein PsbQ, the CA activity of all these proteins depends on the presence of Mn2+: the purified protein PsbO did not show CA activity before adding Mn2+ into the medium (concentration of Mn2+ required for 50% effect, EC(50), was 670 microM); CA activity of protein mixture composed of PsbP and PsbQ increased more than 5-fold upon adding Mn2+ (EC(50) was 45 microM). CA activity of purified protein PsbP increased 2-fold in the presence of 200 microM Mn2+. As indicated for the mixture of two proteins (PsbP and PsbQ), Mg2+, Ca2+, and Zn2+, in contrast to Mn2+, suppressed CA activity (both initial and Mn2+-induced activity). Since the found sources of CA activity demonstrated properties different from ones of typical CA (need for Mn2+, insensitivity or low sensitivity to acetazolamide or ethoxyzolamide) and such CA activity was found only among PS II proteins, we cannot exclude that they belong to the type of Mn-dependent CA associated with PS II.

  20. Zebra chip disease decreases tuber (Solanum tuberosum L.) protein content by attenuating protease inhibitor levels and increasing protease activities.

    PubMed

    Kumar, G N Mohan; Knowles, Lisa O; Knowles, N Richard

    2015-11-01

    Zebra chip disease of potato decreases protease inhibitor levels resulting in enhanced serine-type protease activity, decreased protein content and altered protein profiles of fully mature tubers. Zebra-chip (ZC), caused by Candidatus Liberibacter solanacearum (CLso), is a relatively new disease of potato that negatively affects growth, yield, propagation potential, and fresh and process qualities of tubers. Diseased plants produce tubers with characteristic brown discoloration of vascular tissue accompanied by elevated levels of free amino acids and reducing sugars. Here we demonstrate that ZC disease induces selective protein catabolism in tubers through modulating protease inhibitor levels. Soluble protein content of tubers from CLso-infected plants was 33% lower than from non-infected plants and electrophoretic analyses revealed substantial reductions in major tuber proteins. Patatin (~40 kDa) and ser-, asp- (22 kDa) and cys-type (85 kDa) protease inhibitors were either absent or greatly reduced in ZC-afflicted tubers. In contrast to healthy (non-infected) tubers, the proteolytic activity in CLso infected tubers was high and the ability of extracts from infected tubers to inhibit trypsin (ser-type) and papain (cys-type) proteases greatly attenuated. Moreover, extracts from CLso-infected tubers rapidly catabolized proteins purified from healthy tubers (40 kDa patatin, 22 kDa protease inhibitors, 85 kDa potato multicystatin) when subjected to proteolysis individually. In contrast, crude extracts from non-infected tubers effectively inhibited the proteolytic activity from ZC-afflicted tubers. These results suggest that the altered protein profile of ZC afflicted tubers is largely due to loss of ser- and cys-type protease inhibitors. Further analysis revealed a novel PMSF-sensitive (ser) protease (ca. 80-120 kDa) in CLso infected tubers. PMSF abolished the proteolytic activities responsible for degrading patatin, the 22 kDa protease inhibitor(s) and potato

  1. Collagenase-3 binds to a specific receptor and requires the low density lipoprotein receptor-related protein for internalization

    NASA Technical Reports Server (NTRS)

    Barmina, O. Y.; Walling, H. W.; Fiacco, G. J.; Freije, J. M.; Lopez-Otin, C.; Jeffrey, J. J.; Partridge, N. C.

    1999-01-01

    We have previously identified a specific receptor for collagenase-3 that mediates the binding, internalization, and degradation of this ligand in UMR 106-01 rat osteoblastic osteosarcoma cells. In the present study, we show that collagenase-3 binding is calcium-dependent and occurs in a variety of cell types, including osteoblastic and fibroblastic cells. We also present evidence supporting a two-step mechanism of collagenase-3 binding and internalization involving both a specific collagenase-3 receptor and the low density lipoprotein receptor-related protein. Ligand blot analysis shows that (125)I-collagenase-3 binds specifically to two proteins ( approximately 170 kDa and approximately 600 kDa) present in UMR 106-01 cells. Western blotting identified the 600-kDa protein as the low density lipoprotein receptor-related protein. Our data suggest that the 170-kDa protein is a specific collagenase-3 receptor. Low density lipoprotein receptor-related protein-null mouse embryo fibroblasts bind but fail to internalize collagenase-3, whereas UMR 106-01 and wild-type mouse embryo fibroblasts bind and internalize collagenase-3. Internalization, but not binding, is inhibited by the 39-kDa receptor-associated protein. We conclude that the internalization of collagenase-3 requires the participation of the low density lipoprotein receptor-related protein and propose a model in which the cell surface interaction of this ligand requires a sequential contribution from two receptors, with the collagenase-3 receptor acting as a high affinity primary binding site and the low density lipoprotein receptor-related protein mediating internalization.

  2. Myelin management by the 18.5–kDa and 21.5–kDa classic myelin basic protein isoforms

    PubMed Central

    Harauz, George; Boggs, Joan M.

    2013-01-01

    The classic myelin basic protein (MBP) splice isoforms range in nominal molecular mass from 14 to 21.5 kDa, and arise from the gene in the oligodendrocyte lineage (Golli) in maturing oligodendrocytes. The 18.5-kDa isoform that predominates in adult myelin adheres the cytosolic surfaces of oligodendrocyte membranes together, and forms a two-dimensional molecular sieve restricting protein diffusion into compact myelin. However, this protein has additional roles including cytoskeletal assembly and membrane extension, binding to SH3-domains, participation in Fyn-mediated signaling pathways, sequestration of phosphoinositides, and maintenance of calcium homeostasis. Of the diverse post-translational modifications of this isoform, phosphorylation is the most dynamic, and modulates 18.5-kDa MBP’s protein-membrane and protein-protein interactions, indicative of a rich repertoire of functions. In developing and mature myelin, phosphorylation can result in microdomain or even nuclear targeting of the protein, supporting the conclusion that 18.5-kDa MBP has significant roles beyond membrane adhesion. The full-length, early-developmental 21.5-kDa splice isoform is predominantly karyophilic due to a non-traditional P-Y nuclear localization signal, with effects such as promotion of oligodendrocyte proliferation. We discuss in vitro and recent in vivo evidence for multifunctionality of these classic basic proteins of myelin, and argue for a systematic evaluation of the temporal and spatial distributions of these protein isoforms, and their modified variants, during oligodendrocyte differentiation. PMID:23398367

  3. Physicochemical stability and in vitro bioaccessibility of ß-carotene nanoemulsions stabilized with whey protein-dextran conjugates

    USDA-ARS?s Scientific Manuscript database

    In this study, ß-carotene (BC)-loaded nanoemulsions encapsulated with native whey protein isolate (WPI) and WPI-dextran (DT, 5 kDa, 20 kDa, and 70 kDa) conjugates were prepared and the effects of glycosylation with various molecular weight DTs on the physicochemical property, lipolysis, and BC bioac...

  4. Estrogen Receptor β and Its Domains Interact with Casein Kinase 2, Phosphokinase C, and N-Myristoylation Sites of Mitochondrial and Nuclear Proteins in Mouse Brain*

    PubMed Central

    Paramanik, Vijay; Thakur, Mahendra Kumar

    2012-01-01

    The localization of estrogen receptor (ER)β in mitochondria suggests ERβ-dependent regulation of genes, which is poorly understood. Here, we analyzed the ERβ interacting mitochondrial as well as nuclear proteins in mouse brain using pull-down assay and matrix-assisted laser desorption ionization mass spectroscopy (MALDI-MS). In the case of mitochondria, ERβ interacted with six proteins of 35–152 kDa, its transactivation domain (TAD) interacted with four proteins of 37–172 kDa, and ligand binding domain (LBD) interacted with six proteins of 37–161 kDa. On the other hand, in nuclei, ERβ interacted with seven proteins of 30–203 kDa, TAD with ten proteins of 31–160 kDa, and LBD with fourteen proteins of 42–179 kDa. For further identification, these proteins were cleaved by trypsin into peptides and analyzed by MALDI-MS using mascot search engine, immunoprecipitation, immunoblotting, and far-Western blotting. To find the consensus binding motifs in interacting proteins, their unique tryptic peptides were analyzed by the motif scan software. All the interacting proteins were found to contain casein kinase (CK) 2, phosphokinase (PK)C phosphorylation, and N-myristoylation sites. These were further confirmed by peptide pull-down assays using specific mutations in the interacting sites. Thus, the present findings provide evidence for the interaction of ERβ with specific mitochondrial and nuclear proteins through consensus CK2, PKC phosphorylation, and N-myristoylation sites, and may represent an essential step toward designing selective ER modulators for regulating estrogen-mediated signaling. PMID:22566700

  5. The Scl1 protein of M6-type group A Streptococcus binds the human complement regulatory protein, factor H, and inhibits the alternative pathway of complement.

    PubMed

    Caswell, Clayton C; Han, Runlin; Hovis, Kelley M; Ciborowski, Pawel; Keene, Douglas R; Marconi, Richard T; Lukomski, Slawomir

    2008-02-01

    Non-specific activation of the complement system is regulated by the plasma glycoprotein factor H (FH). Bacteria can avoid complement-mediated opsonization and phagocytosis through acquiring FH to the cell surface. Here, we characterize an interaction between the streptococcal collagen-like protein Scl1.6 of M6-type group A Streptococcus (GAS) and FH. Using affinity chromatography with immobilized recombinant Scl1.6 protein, we co-eluted human plasma proteins with molecular weight of 155 kDa, 43 kDa and 38 kDa. Mass spectrometry identified the 155 kDa band as FH and two other bands as isoforms of the FH-related protein-1. The identities of all three bands were confirmed by Western immunoblotting with specific antibodies. Structure-function relation studies determined that the globular domain of the Scl1.6 variant specifically binds FH while fused to collagenous tails of various lengths. This binding is not restricted to Scl1.6 as the phylogenetically linked Scl1.55 variant also binds FH. Functional analyses demonstrated the cofactor activity of the rScl1.6-bound FH for factor I-mediated cleavage of C3b. Finally, purified FH bound to the Scl1.6 protein present in the cell wall material obtained from M6-type GAS. In conclusion, we have identified a functional interaction between Scl1 and plasma FH, which may contribute to GAS evasion of complement-mediated opsonization and phagocytosis.

  6. Inhibition of CDC25B Phosphatase Through Disruption of Protein–Protein Interaction

    DOE PAGES

    Lund, George; Dudkin, Sergii; Borkin, Dmitry; ...

    2014-11-25

    CDC25 phosphatases are key cell cycle regulators and represent very attractive but challenging targets for anticancer drug discovery. Here in this paper, we explored whether fragment-based screening represents a valid approach to identify inhibitors of CDC25B. This resulted in identification of 2-fluoro-4-hydroxybenzonitrile, which directly binds to the catalytic domain of CDC25B. Interestingly, NMR data and the crystal structure demonstrate that this compound binds to the pocket distant from the active site and adjacent to the protein–protein interaction interface with CDK2/Cyclin A substrate. Furthermore, we developed a more potent analogue that disrupts CDC25B interaction with CDK2/Cyclin A and inhibits dephosphorylation ofmore » CDK2. Based on these studies, we provide a proof of concept that targeting CDC25 phosphatases by inhibiting their protein–protein interactions with CDK2/Cyclin A substrate represents a novel, viable opportunity to target this important class of enzymes.« less

  7. Silencing the hsp25 Gene Eliminates Migration Capability of the Highly Metastatic Murine 4T1 Breast Adenocarcinoma Cell

    PubMed Central

    Bausero, Maria A.; Bharti, Ajit; Page, Diana T.; Perez, Kristen D.; Eng, Jason W.-L.; Ordonez, Susana L.; Jantschitsch, Christian; Kindas-Muegge, Ingela; Ciocca, Daniel; Asea, Alexzander

    2006-01-01

    The 25-kDa heat shock protein (Hsp25) is associated with various malignancies and is expressed at high levels in biopsies as well as circulating in the serum of breast cancer patients. In this study, we used RNA interference technology to silence the hsp25 gene in 4T1 breast adenocarcinoma cells, known as a poorly immunogenic, highly metastatic cell line. We demonstrate that transfection of 4T1 cells with short interference RNA-Hsp25 dramatically inhibits proliferation as compared with control transfected cells. In addition, we show that 4T1 cells transfected with short interference RNA-Hsp25 abrogates tumor migration potential by a mechanism that is in part due to the repression of matrix metalloproteinase 9 expression and a concomitant upregulation of its antagonist, tissue inhibitor metalloproteinase 1. Taken together, these findings provide a model system for the study of metastatic potential of tumors and are suggestive of an earlier unrecognized role for Hsp25 in tumor migration. PMID:16340246

  8. Purification and characterization of parvalbumins, the major allergens in red stingray (Dasyatis akajei).

    PubMed

    Cai, Qiu-Feng; Liu, Guang-Ming; Li, Teng; Hara, Kenji; Wang, Xi-Chang; Su, Wen-Jin; Cao, Min-Jie

    2010-12-22

    Fish has received increasing attention because it induces IgE-mediated food allergy. Parvalbumin (PV) represents the major allergen of fish, and IgE cross-reactivity to PV in various teleost fish species has been shown, while little information is available about allergens in elasmobranch fish. In this study, two PV isoforms (named as PV-I and PV-II) from red stingray (Dasyatis akajei) were purified to homogeneity by a series of procedures including ammonium sulfate precipitation and column chromatographies of DEAE-Sepharose and Sephacryl S-200. Purified PVs revealed a single band on tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The molecular masses of PV-I and PV-II were 12.29 and 11.95 kDa, respectively, as determined by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Western blot using antifrog PV monoclonal antibody (PARV-19) showed positive reactions to the two proteins, confirming that they were PVs, although their immunological reactivities were weaker than those of PV from silver carp. The N-terminal amino acid sequence of PV-I was determined, and comparison with PVs from other fish species showed low homology between teleost and elasmobranch fish. The isoelectric points of PV-I and PV-II were 5.4 and 5.0, respectively, as determined by two-dimensional electrophoresis (2-DE), suggesting that both isoforms belong to the α-group. IgE immunoblotting analysis showed that sera from fish-allergic patients reacted to both PV-I and PV-II from red stingray. Thermal stability revealed that PV-I easily formed oligomers than PV-II, which might contribute to the maintenance of its allerginicity during heat processing.

  9. Insights into the Structure of the Vip3Aa Insecticidal Protein by Protease Digestion Analysis

    PubMed Central

    Bel, Yolanda; Banyuls, Núria; Chakroun, Maissa; Escriche, Baltasar; Ferré, Juan

    2017-01-01

    Vip3 proteins are secretable proteins from Bacillus thuringiensis whose mode of action is still poorly understood. In this study, the activation process for Vip3 proteins was closely examined in order to better understand the Vip3Aa protein stability and to shed light on its structure. The Vip3Aa protoxin (of 89 kDa) was treated with trypsin at concentrations from 1:100 to 120:100 (trypsin:Vip3A, w:w). If the action of trypsin was not properly neutralized, the results of SDS-PAGE analysis (as well as those with Agrotis ipsilon midgut juice) equivocally indicated that the protoxin could be completely processed. However, when the proteolytic reaction was efficiently stopped, it was revealed that the protoxin was only cleaved at a primary cleavage site, regardless of the amount of trypsin used. The 66 kDa and the 19 kDa peptides generated by the proteases co-eluted after gel filtration chromatography, indicating that they remain together after cleavage. The 66 kDa fragment was found to be extremely resistant to proteases. The trypsin treatment of the protoxin in the presence of SDS revealed the presence of secondary cleavage sites at S-509, and presumably at T-466 and V-372, rendering C-terminal fragments of approximately 29, 32, and 42 kDa, respectively. The fact that the predicted secondary structure of the Vip3Aa protein shows a cluster of beta sheets in the C-terminal region of the protein might be the reason behind the higher stability to proteases compared to the rest of the protein, which is mainly composed of alpha helices. PMID:28387713

  10. A 170kDa multi-domain cystatin of Fasciola gigantica is active in the male reproductive system.

    PubMed

    Geadkaew, Amornrat; Kosa, Nanthawat; Siricoon, Sinee; Grams, Suksiri Vichasri; Grams, Rudi

    2014-09-01

    Cystatins are functional as intra- and extracellular inhibitors of cysteine proteases and are expressed as single or multi-domain proteins. We have previously described two single domain type 1 cystatins in the trematode Fasciola gigantica that are released into the parasite's intestinal tract and exhibit inhibitory activity against endogenous and host cathepsin L and B proteases. In contrast, the here presented 170kDa multi-domain cystatin (FgMDC) comprises signal peptide and 12 tandem repeated cystatin-like domains with similarity to type 2 single domain cystatins. The domains show high sequence divergence with identity values often <20% and at only 26.8% between the highest matching domains 6 and 10. Several domains contain degenerated QVVAG core motifs and/or lack other important residues of active type 2 cystatins. Domain-specific antisera detected multiple forms of FgMDC ranging from <10 to >120kDa molecular mass in immunoblots of parasite crude extracts and ES product with different banding patterns for each antiserum demonstrating complex processing of the proprotein. The four domains with the highest conserved QVVAG motifs were expressed in Escherichia coli and the refolded recombinant proteins blocked cysteine protease activity in the parasite's ES product. Strikingly, immunohistochemical analysis using seven domain-specific antisera localized FgMDC in testis lobes and sperm. It is speculated that the processed cystatin-like domains have function analogous to the mammalian group of male reproductive tissue-specific type 2 cystatins and are functional in spermiogenesis and fertilization. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. The orphan G protein-coupled receptor 25 (GPR25) is activated by Apelin and Apela in non-mammalian vertebrates.

    PubMed

    Zhang, Jiannan; Wan, Yiping; Fang, Chao; Chen, Junan; Ouyang, Wangan; Li, Juan; Wang, Yajun

    2018-06-22

    G protein-coupled receptor 25 (GPR25) is an orphan G protein-coupled receptor in vertebrates, that has been implicated to be associated with autoimmune diseases and regulate blood pressure in humans. However, the endogenous ligand of GPR25 remains unknown in vertebrates. Here, we reported that in non-mammalian vertebrates (zebrafish, spotted gars, and pigeons), GPR25 could be activated by Apelin and Apela peptides, which are also the two endogenous ligands of vertebrate Apelin receptor (APLNR). Using the pGL3-CRE-luciferase reporter assay and confocal microscopy, we first demonstrated that like APLNR, zebrafish GPR25 expressing in HEK293 cells could be effectively activated by zebrafish Apelin and Apela peptides, leading to the inhibition of forskolin-stimulated cAMP production and receptor internalization. Like zebrafish GPR25, pigeon and spotted gar GPR25 could also be activated by Apelin and Apela, and their activation could inhibit forskolin-induced cAMP accumulation. Interestingly, unlike zebrafish (/spotted gar/pigeon) GPR25, human GPR25 could not be activated by Apelin and Apela under the same experimental conditions. RNA-seq analysis further revealed that GPR25 is expressed in a variety of tissues, including the testes and intestine of zebrafish/spotted gars/humans, implying the potential roles of GPR25 signaling in many physiological processes in vertebrates. Taken together, our data not only provides the first proof that the orphan receptor GPR25 possesses two potential ligands 'Apelin and Apela' and its activation decreases intracellular cAMP levels in non-mammalian vertebrates, but also facilitates to unravel the physiological roles of GPR25 signaling in vertebrates. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Up-Regulation of Antioxidant Proteins in the Plasma Proteome during Saturation Diving: Unique Coincidence under Hypobaric Hypoxia.

    PubMed

    Domoto, Hideharu; Iwaya, Keiichi; Ikomi, Fumitaka; Matsuo, Hirotaka; Tadano, Yutaka; Fujii, Shigenori; Tachi, Kazuyoshi; Itoh, Yoshiyuki; Sato, Michiya; Inoue, Kimitoshi; Shinomiya, Nariyoshi

    2016-01-01

    Saturation diving (SD) is one of the safest techniques for tolerating hyperbaric conditions for long durations. However, the changes in the human plasma protein profile that occur during SD are unknown. To identify differential protein expression during or after SD, 65 blood samples from 15 healthy Japanese men trained in SD were analyzed by two-dimensional fluorescence difference gel electrophoresis. The expression of two proteins, one 32.4 kDa with an isoelectric point (pI) of 5.8 and the other 44.8 kDa with pI 4.0, were elevated during SD to 60, 100, and 200 meters sea water (msw). The expression of these proteins returned to pre-diving level when the SD training was completed. The two proteins were identified using in-gel digestion and mass spectrometric analysis; the 32.4 kDa protein was transthyretin and the 44.8 kDa protein was alpha-1-acid glycoprotein 1. Oxidation was detected at methionine 13 of transthyretin and at methionine 129 of alpha-1-acid glycoprotein 1 by tandem mass spectrometry. Moreover, haptoglobin was up-regulated during the decompression phase of 200 msw. These plasma proteins up-regulated during SD have a common function as anti-oxidants. This suggests that by coordinating their biological effects, these proteins activate a defense mechanism to counteract the effects of hyperbaric-hyperoxic conditions during SD.

  13. Up-Regulation of Antioxidant Proteins in the Plasma Proteome during Saturation Diving: Unique Coincidence under Hypobaric Hypoxia

    PubMed Central

    Domoto, Hideharu; Iwaya, Keiichi; Ikomi, Fumitaka; Matsuo, Hirotaka; Tadano, Yutaka; Fujii, Shigenori; Tachi, Kazuyoshi; Itoh, Yoshiyuki; Sato, Michiya; Inoue, Kimitoshi; Shinomiya, Nariyoshi

    2016-01-01

    Saturation diving (SD) is one of the safest techniques for tolerating hyperbaric conditions for long durations. However, the changes in the human plasma protein profile that occur during SD are unknown. To identify differential protein expression during or after SD, 65 blood samples from 15 healthy Japanese men trained in SD were analyzed by two-dimensional fluorescence difference gel electrophoresis. The expression of two proteins, one 32.4 kDa with an isoelectric point (pI) of 5.8 and the other 44.8 kDa with pI 4.0, were elevated during SD to 60, 100, and 200 meters sea water (msw). The expression of these proteins returned to pre-diving level when the SD training was completed. The two proteins were identified using in-gel digestion and mass spectrometric analysis; the 32.4 kDa protein was transthyretin and the 44.8 kDa protein was alpha-1-acid glycoprotein 1. Oxidation was detected at methionine 13 of transthyretin and at methionine 129 of alpha-1-acid glycoprotein 1 by tandem mass spectrometry. Moreover, haptoglobin was up-regulated during the decompression phase of 200 msw. These plasma proteins up-regulated during SD have a common function as anti-oxidants. This suggests that by coordinating their biological effects, these proteins activate a defense mechanism to counteract the effects of hyperbaric-hyperoxic conditions during SD. PMID:27741252

  14. Molecular cloning and nucleotide sequences of the genes for two essential proteins constituting a novel enzyme system for heptaprenyl diphosphate synthesis.

    PubMed

    Koike-Takeshita, A; Koyama, T; Obata, S; Ogura, K

    1995-08-04

    The genes encoding two dissociable components essential for Bacillus stearothermophilus heptaprenyl diphosphate synthase (all-trans-hexparenyl-diphosphate:isopentenyl-diphosphate hexaprenyl-trans-transferase, EC 2.5.1.30) were cloned, and their nucleotide sequences were determined. Sequence analyses revealed the presence of three open reading frames within 2,350 base pairs, designated as ORF-1, ORF-2, and ORF-3 in order of nucleotide sequence, which encode proteins of 220, 234, and 323 amino acids, respectively. Deletion experiments have shown that expression of the enzymatic activity requires the presence of ORF-1 and ORF-3, but ORF-2 is not essential. As a result, this enzyme was proved genetically to consist of two different protein compounds with molecular masses of 25 kDa (Component I) and 36 kDa (Component II), encoded by two of the three tandem genes. The protein encoded by ORF-1 has no similarity to any protein so far registered. However, the protein encoded by ORF-3 shows a 32% similarity to the farnesyl diphosphate synthase of the same bacterium and has seven highly conserved regions that have been shown typical in prenyltransferases (Koyama, T., Obata, S., Osabe, M., Takeshita, A., Yokoyama, K., Uchida, M., Nishino, T., and Ogura, K. (1993) J. Biochem. (Tokyo) 113, 355-363).

  15. Paramyxovirus V Proteins Interact with the RIG-I/TRIM25 Regulatory Complex and Inhibit RIG-I Signaling.

    PubMed

    Sánchez-Aparicio, Maria T; Feinman, Leighland J; García-Sastre, Adolfo; Shaw, Megan L

    2018-03-15

    Paramyxovirus V proteins are known antagonists of the RIG-I-like receptor (RLR)-mediated interferon induction pathway, interacting with and inhibiting the RLR MDA5. We report interactions between the Nipah virus V protein and both RIG-I regulatory protein TRIM25 and RIG-I. We also observed interactions between these host proteins and the V proteins of measles virus, Sendai virus, and parainfluenza virus. These interactions are mediated by the conserved C-terminal domain of the V protein, which binds to the tandem caspase activation and recruitment domains (CARDs) of RIG-I (the region of TRIM25 ubiquitination) and to the SPRY domain of TRIM25, which mediates TRIM25 interaction with the RIG-I CARDs. Furthermore, we show that V interaction with TRIM25 and RIG-I prevents TRIM25-mediated ubiquitination of RIG-I and disrupts downstream RIG-I signaling to the mitochondrial antiviral signaling protein. This is a novel mechanism for innate immune inhibition by paramyxovirus V proteins, distinct from other known V protein functions such as MDA5 and STAT1 antagonism. IMPORTANCE The host RIG-I signaling pathway is a key early obstacle to paramyxovirus infection, as it results in rapid induction of an antiviral response. This study shows that paramyxovirus V proteins interact with and inhibit the activation of RIG-I, thereby interrupting the antiviral signaling pathway and facilitating virus replication. Copyright © 2018 American Society for Microbiology.

  16. Intentional formation of a protein corona on nanoparticles: Serum concentration affects protein corona mass, surface charge, and nanoparticle-cell interaction.

    PubMed

    Gräfe, Christine; Weidner, Andreas; Lühe, Moritz V D; Bergemann, Christian; Schacher, Felix H; Clement, Joachim H; Dutz, Silvio

    2016-06-01

    The protein corona, which immediately is formed after contact of nanoparticles and biological systems, plays a crucial role for the biological fate of nanoparticles. In the here presented study we describe a strategy to control the amount of corona proteins which bind on particle surface and the impact of such a protein corona on particle-cell interactions. For corona formation, polyethyleneimine (PEI) coated magnetic nanoparticles (MNP) were incubated in a medium consisting of fetal calf serum (FCS) and cell culture medium. To modulate the amount of proteins bind to particles, the composition of the incubation medium was varied with regard to the FCS content. The protein corona mass was estimated and the size distribution of the participating proteins was determined by means of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Additionally, the zeta potential of incubated particles was measured. Human blood-brain barrier-representing cell line HBMEC was used for in vitro incubation experiments. To investigate the consequences of the FCS dependent protein corona formation on the interaction of MNP and cells flow cytometry and laser scanning microscopy were used. Zeta potential as well as SDS-PAGE clearly reveal an increase in the amount of corona proteins on MNP with increasing amount of FCS in incubation medium. For MNP incubated with lower FCS concentrations especially medium-sized proteins of molecular weights between 30kDa and 100kDa could be found within the protein corona, whereas for MNP incubated within higher FCS concentrations the fraction of corona proteins of 30kDa and less increased. The presence of the protein corona reduces the interaction of PEI-coated MNP with HBMEC cells within a 30min-incubation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Serum immunoglobulin E and immunoglobulin G reactivity to Agaricus bisporus proteins in mushroom cultivation workers.

    PubMed

    Khakzad, Z; Hedayati, M T; Mahdian, S; Mayahi, S

    2015-06-01

    Although molds are regarded as the main fungal allergen sources, evidence indicates that spores of Basidiomycota including Agaricus bisporus ( A. bisporus ) can be also found at high concentrations in the environment and may cause as many respiratory allergies as molds. The aim of the present study was to evaluate specific immunoglobulin E (IgE) and immunoglobulin G (IgG) antibodies against A. bisporus via immunoblotting technique in individuals working at mushroom cultivation centers. In this study, 72 workers involved in the cultivation and harvest of button mushrooms were enrolled. For the analysis of serum IgE and IgG, A. bisporus grown in Sabouraud dextrose broth was harvested and ruptured by liquid nitrogen and glass beads. The obtained sample was centrifuged and the supernatant was collected as "crude extract" (CE). CE was separated via Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE). The separated proteins were transferred to a nitrocellulose filter and the bands responsive to IgE and IgG were identified by anti-human conjugated antibodies. All participants were screened in terms of total IgE level. Among 72 workers, 18 (25%) had a total IgE level higher than 188 IU/mL. In SDS-PAGE, the CE of A. bisporus showed 23 different protein bands with a molecular weight range of 13-80 kDa. The sera of 23.6% and 55.5% of participants showed positive response, with specific IgE and IgG antibodies against A. bisporus in the blot, respectively. The bands with molecular weights of 62 and 68 kDa were the most reactive protein components of A. bisporus to specific IgE antibodies. Moreover, bands with molecular weights of 57 and 62 kDa showed the highest reactivity to IgG, respectively. Also, 62 and 68 kDa components were the most reactive bands with both specific IgG and IgE antibodies. The obtained findings revealed that A. bisporus has different allergens and antigens, which contribute to its potential as an aeroallergen in hypersensitivity

  18. CLONING AND EXPRESSION OF THE TRANSLOCATOR PROTEIN (18 KDA), VOLTAGE-DEPENDENT ANION CHANNEL, AND DIAZEPAM BINDING INHIBITOR IN THE GONAD OF LARGEMOUTH BASS (MICROPTERUS SALMOIDES) ACROSS THE REPRODUCTIVE CYCLE

    PubMed Central

    Doperalski, Nicholas J.; Martyniuk, Christopher J.; Prucha, Melinda S.; Kroll, Kevin J.; Denslow, Nancy D.; Barber, David S.

    2011-01-01

    Cholesterol transport across the mitochondrial membrane is rate-limiting for steroidogenesis in vertebrates. Previous studies in fish have characterized expression of the steroidogenic acute regulatory protein, however the function and regulation of other genes and proteins involved in piscine cholesterol transport have not been evaluated. In the current study, mRNA sequences of the 18 kDa translocator protein (tspo; formerly peripheral benzodiazepine receptor), voltage-dependent anion channel (vdac), and diazepam binding inhibitor (dbi; also acyl-CoA binding protein) were cloned from largemouth bass. Gonadal expression was examined across reproductive stages to determine if expression is correlated with changes in steroid levels and with indicators of reproductive maturation. In testis, transcript abundance of tspo and dbi increased with reproductive maturation (6- and 23-fold maximal increase, respectively) and expression of tspo and dbi was positively correlated with reproductive stage, gonadosomatic index (GSI), and circulating levels of testosterone. Testis vdac expression was positively correlated with reproductive stage and GSI. In females, gonadal tspo and vdac expression was negatively correlated with GSI and levels of plasma testosterone and 17β-estradiol. Ovarian dbi expression was not correlated with indicators of reproductive maturation. These studies represent the first investigation of the steroidogenic role of tspo, vdac, and dbi in fish. Findings suggest that cholesterol transport in largemouth bass testis, but not ovary, may be transcriptionally-regulated, however further investigation will be necessary to fully elucidate the role of these genes in largemouth bass steroidogenesis. PMID:21600210

  19. The Zds proteins control entry into mitosis and target protein phosphatase 2A to the Cdc25 phosphatase

    PubMed Central

    Wicky, Sidonie; Tjandra, Hendri; Schieltz, David; Yates, John; Kellogg, Douglas R.

    2011-01-01

    The Wee1 kinase restrains entry into mitosis by phosphorylating and inhibiting cyclin-dependent kinase 1 (Cdk1). The Cdc25 phosphatase promotes entry into mitosis by removing Cdk1 inhibitory phosphorylation. Experiments in diverse systems have established that Wee1 and Cdc25 are regulated by protein phosphatase 2A (PP2A), but a full understanding of the function and regulation of PP2A in entry into mitosis has remained elusive. In budding yeast, entry into mitosis is controlled by a specific form of PP2A that is associated with the Cdc55 regulatory subunit (PP2ACdc55). We show here that related proteins called Zds1 and Zds2 form a tight stoichiometric complex with PP2ACdc55 and target its activity to Cdc25 but not to Wee1. Conditional inactivation of the Zds proteins revealed that their function is required primarily at entry into mitosis. In addition, Zds1 undergoes cell cycle–dependent changes in phosphorylation. Together, these observations define a role for the Zds proteins in controlling specific functions of PP2ACdc55 and suggest that upstream signals that regulate PP2ACdc55 may play an important role in controlling entry into mitosis. PMID:21119008

  20. The Zds proteins control entry into mitosis and target protein phosphatase 2A to the Cdc25 phosphatase.

    PubMed

    Wicky, Sidonie; Tjandra, Hendri; Schieltz, David; Yates, John; Kellogg, Douglas R

    2011-01-01

    The Wee1 kinase restrains entry into mitosis by phosphorylating and inhibiting cyclin-dependent kinase 1 (Cdk1). The Cdc25 phosphatase promotes entry into mitosis by removing Cdk1 inhibitory phosphorylation. Experiments in diverse systems have established that Wee1 and Cdc25 are regulated by protein phosphatase 2A (PP2A), but a full understanding of the function and regulation of PP2A in entry into mitosis has remained elusive. In budding yeast, entry into mitosis is controlled by a specific form of PP2A that is associated with the Cdc55 regulatory subunit (PP2A(Cdc55)). We show here that related proteins called Zds1 and Zds2 form a tight stoichiometric complex with PP2A(Cdc55) and target its activity to Cdc25 but not to Wee1. Conditional inactivation of the Zds proteins revealed that their function is required primarily at entry into mitosis. In addition, Zds1 undergoes cell cycle-dependent changes in phosphorylation. Together, these observations define a role for the Zds proteins in controlling specific functions of PP2A(Cdc55) and suggest that upstream signals that regulate PP2A(Cdc55) may play an important role in controlling entry into mitosis.

  1. Reflections on protein splicing: structures, functions and mechanisms

    PubMed Central

    Anraku, Yasuhiro; Satow, Yoshinori

    2009-01-01

    Twenty years ago, evidence that one gene produces two enzymes via protein splicing emerged from structural and expression studies of the VMA1 gene in Saccharomyces cerevisiae. VMA1 consists of a single open reading frame and contains two independent genetic information for Vma1p (a catalytic 70-kDa subunit of the vacuolar H+-ATPase) and VDE (a 50-kDa DNA endonuclease) as an in-frame spliced insert in the gene. Protein splicing is a posttranslational cellular process, in which an intervening polypeptide termed as the VMA1 intein is self-catalytically excised out from a nascent 120-kDa VMA1 precursor and two flanking polypeptides of the N- and C-exteins are ligated to produce the mature Vma1p. Subsequent studies have demonstrated that protein splicing is not unique to the VMA1 precursor and there are many operons in nature, which implement genetic information editing at protein level. To elucidate its structure-directed chemical mechanisms, a series of biochemical and crystal structural studies has been carried out with the use of various VMA1 recombinants. This article summarizes a VDE-mediated self-catalytic mechanism for protein splicing that is triggered and terminated solely via thiazolidine intermediates with tetrahedral configurations formed within the splicing sites where proton ingress and egress are driven by balanced protonation and deprotonation. PMID:19907126

  2. Protein Buffering in Model Systems and in Whole Human Saliva

    PubMed Central

    Lamanda, Andreas; Cheaib, Zeinab; Turgut, Melek Dilek; Lussi, Adrian

    2007-01-01

    The aim of this study was to quantify the buffer attributes (value, power, range and optimum) of two model systems for whole human resting saliva, the purified proteins from whole human resting saliva and single proteins. Two model systems, the first containing amyloglucosidase and lysozyme, and the second containing amyloglucosidase and α-amylase, were shown to provide, in combination with hydrogencarbonate and di-hydrogenphosphate, almost identical buffer attributes as whole human resting saliva. It was further demonstrated that changes in the protein concentration as small as 0.1% may change the buffer value of a buffer solution up to 15 times. Additionally, it was shown that there was a protein concentration change in the same range (0.16%) between saliva samples collected at the time periods of 13:00 and others collected at 9:00 am and 17:00. The mode of the protein expression changed between these samples corresponded to the change in basic buffer power and the change of the buffer value at pH 6.7. Finally, SDS Page and Ruthenium II tris (bathophenantroline disulfonate) staining unveiled a constant protein expression in all samples except for one 50 kDa protein band. As the change in the expression pattern of that 50 kDa protein band corresponded to the change in basic buffer power and the buffer value at pH 6.7, it was reasonable to conclude that this 50 kDa protein band may contain the protein(s) belonging to the protein buffer system of human saliva. PMID:17327922

  3. beta. -Amyloid precursor protein of Alzheimer disease occurs as 110- to 135-kilodalton membrane-associated proteins in neural and nonneural tissues

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Selkoe, D.J.; Podlisny, M.B.; Joachim, C.L.

    1988-10-01

    Progressive cerebral deposition of extracellular filaments composed of the {beta}-amyloid protein ({beta}AP) is a constant feature of Alzheimer disease (AD). Since the gene on chromosome 21 encoding the {beta}AP precursor ({beta}APP) is not known to be altered in AD, transcriptional or posttranslational changes may underlie accelerated {beta}AP deposition. Using two antibodies to the predicted carboxyl terminus of {beta}APP, the authors have identified the native {beta}APP in brain and nonneural human tissues as a 110- to 135-kDa protein complex that is insoluble in buffer and found in various membrane-rich subcellular fractions. These proteins are relatively uniformly distributed in adult brain, abundantmore » in fetal brain, and detected in nonneural tissues that contain {beta}APP mRNA. Similarly sized proteins occur in rat, cow, and monkey brain and in cultured human HL-60 and HeLa cells; the precise patterns in the 110- to 135-kDa range are heterogeneous among various tissues and cell lines. They conclude that the highly conserved {beta}APP molecule occurs in mammalian tissues as a heterogeneous group of membrane-associated proteins of {approx} 120 kDa. Detection of the nonamyloidogenic carboxyl terminus within plaques suggests that proteolytic processing of the {beta}APP into insoluble filaments occurs locally in cortical regions that develop {beta}-amyloid deposits with age.« less

  4. Optimized Negative Staining: a High-throughput Protocol for Examining Small and Asymmetric Protein Structure by Electron Microscopy

    DOE PAGES

    Rames, Matthew; Yu, Yadong; Ren, Gang

    2014-08-15

    Structural determination of proteins is rather challenging for proteins with molecular masses between 40 - 200 kDa. Considering that more than half of natural proteins have a molecular mass between 40 - 200 kDa, a robust and high-throughput method with a nanometer resolution capability is needed. Negative staining (NS) electron microscopy (EM) is an easy, rapid, and qualitative approach which has frequently been used in research laboratories to examine protein structure and protein-protein interactions. Unfortunately, conventional NS protocols often generate structural artifacts on proteins, especially with lipoproteins that usually form presenting rouleaux artifacts. By using images of lipoproteins from cryo-electronmore » microscopy (cryo-EM) as a standard, the key parameters in NS specimen preparation conditions were recently screened and reported as the optimized NS protocol (OpNS), a modified conventional NS protocol. Artifacts like rouleaux can be greatly limited by OpNS, additionally providing high contrast along with reasonably high-resolution (near 1 nm) images of small and asymmetric proteins. These high-resolution and high contrast images are even favorable for an individual protein (a single object, no average) 3D reconstruction, such as a 160 kDa antibody, through the method of electron tomography. Moreover, OpNS can be a high-throughput tool to examine hundreds of samples of small proteins. For example, the previously published mechanism of 53 kDa cholesteryl ester transfer protein (CETP) involved the screening and imaging of hundreds of samples. Considering cryo-EM rarely successfully images proteins less than 200 kDa has yet to publish any study involving screening over one hundred sample conditions, it is fair to call OpNS a high-throughput method for studying small proteins. Hopefully the OpNS protocol presented here can be a useful tool to push the boundaries of EM and accelerate EM studies into small protein structure, dynamics and mechanisms.« less

  5. EFFECTS OF AZADIRACHTIN ON CUTICULAR PROTEINS OF SPODOPTERA LITURA (LEPIDOPTERA: NOCTUIDAE) VIS-A-VIS THE MODES OF APPLICATION.

    PubMed

    Yooboon, T; Pluempanupat, W; Koul, Opender; Bullangpoti, V

    2015-01-01

    Azadirachtin is a known botanical insecticide with multiple modes of action. Whether these effects have any relation with the modes of application, specifically during ecdysis process, has been the objective of the present study and accordingly the impairment, if any, among cuticular proteins of Spodoptera litura (Fab.) was determined. Azadirachtin was applied topically, via injection or oral administration. Azadirachtin administered via injection and topical applications severely impaired the ecdysis by 86.67 and 80.0%, respectively. However, this impairment via oral administration was significantly lower (73.33%). Using SDS-PAGE, the cuticular proteins were determined for treated insects under all the three modes of application. In all cases 6 protein bands (MW 9-34 kDa) were identified using markers as standard. In all treatments 3 induced proteins (MW. ~16, 20 and 23 kDa) and 1 reduced protein (~19 kDa) were observed. In case of the topical treatment a different induced protein of ~18 kDa was identified. The change in cuticular proteins, their possible role in ecdysis impairment vis-a-vis the mode of application of azadirachtin is being correlated. This will help in understanding the mode-of-action at cuticular level and also will allow developing a suitable application strategy under field conditions in insect pest management.

  6. Bombyx mori Nucleopolyhedrovirus Encodes a DNA-Binding Protein Capable of Destabilizing Duplex DNA

    PubMed Central

    Mikhailov, Victor S.; Mikhailova, Alla L.; Iwanaga, Masashi; Gomi, Sumiko; Maeda, Susumu

    1998-01-01

    A DNA-binding protein (designated DBP) with an apparent molecular mass of 38 kDa was purified to homogeneity from BmN cells (derived from Bombyx mori) infected with the B. mori nucleopolyhedrovirus (BmNPV). Six peptides obtained after digestion of the isolated protein with Achromobacter protease I were partially or completely sequenced. The determined amino acid sequences indicated that DBP was encoded by an open reading frame (ORF16) located at nucleotides (nt) 16189 to 17139 in the BmNPV genome (GenBank accession no. L33180). This ORF (designated dbp) is a homolog of Autographa californica multicapsid NPV ORF25, whose product has not been identified. BmNPV DBP is predicted to contain 317 amino acids (calculated molecular mass of 36.7 kDa) and to have an isoelectric point of 7.8. DBP showed a tendency to multimerization in the course of purification and was found to bind preferentially to single-stranded DNA. When bound to oligonucleotides, DBP protected them from hydrolysis by phage T4 DNA polymerase-associated 3′→5′ exonuclease. The sizes of the protected fragments indicated that a binding site size for DBP is about 30 nt per protein monomer. DBP, but not BmNPV LEF-3, was capable of unwinding partial DNA duplexes in an in vitro system. This helix-destabilizing ability is consistent with the prediction that DBP functions as a single-stranded DNA binding protein in virus replication. PMID:9525636

  7. SNAP-25 in hippocampal CA3 region is required for long-term memory formation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hou Qiuling; Gao Xiang; Lu Qi

    SNAP-25 is a synaptosomal protein of 25 kDa, a key component of synaptic vesicle-docking/fusion machinery, and plays a critical role in exocytosis and neurotransmitter release. We previously reported that SNAP-25 in the hippocampal CA1 region is involved in consolidation of contextual fear memory and water-maze spatial memory (Hou et al. European J Neuroscience, 20: 1593-1603, 2004). SNAP-25 is expressed not only in the CA1 region, but also in the CA3 region, and the SNAP-25 mRNA level in the CA3 region is higher than in the CA1 region. Here, we provide evidence that SNAP-25 in the CA3 region is also involvedmore » in learning/memory. Intra-CA3 infusion of SNAP-25 antisense oligonucleotide impaired both long-term contextual fear memory and water-maze spatial memory, with short-term memory intact. Furthermore, the SNAP-25 antisense oligonucleotide suppressed the long-term potentiation (LTP) of field excitatory post-synaptic potential (fEPSP) in the mossy-fiber pathway (DG-CA3 pathway), with no effect on paired-pulse facilitation of the fEPSP. These results are consistent with the notion that SNAP-25 in the hippocampal CA3 region is required for long-term memory formation.« less

  8. A new look on protein-polyphenol complexation during honey storage: is this a random or organized event with the help of dirigent-like proteins?

    PubMed

    Brudzynski, Katrina; Sjaarda, Calvin; Maldonado-Alvarez, Liset

    2013-01-01

    Honey storage initiates melanoidin formation that involves a cascade of seemingly unguided redox reactions between amino acids/proteins, reducing sugars and polyphenols. In the process, high molecular weight protein-polyphenol complexes are formed, but the mechanism involved remains unknown. The objective of this study was twofold: to determine quantitative and qualitative changes in proteins in honeys stored for prolonged times and in different temperatures and to relate these changes to the formation of protein-polyphenol complexes. Six -month storage decreased the protein content by 46.7% in all tested honeys (t-test, p<0.002) with the rapid reduction occurring during the first three month. The changes in protein levels coincided with alterations in molecular size and net charge of proteins on SDS -PAGE. Electro-blotted proteins reacted with a quinone-specific nitro blue tetrazolium (NBT) on nitrocellulose membranes indicating that quinones derived from oxidized polyphenols formed covalent bonds with proteins. Protein-polyphenol complexes isolated by size-exclusion chromatography differed in size and stoichiometry and fall into two categories: (a) high molecular weight complexes (230-180 kDa) enriched in proteins but possessing a limited reducing activity toward the NBT and (b) lower molecular size complexes (110-85 kDa) enriched in polyphenols but strongly reducing the dye. The variable stoichiometry suggest that the large, "protein-type" complexes were formed by protein cross-linking, while in the smaller, "polyphenol-type" complexes polyphenols were first polymerized prior to protein binding. Quinones preferentially bound a 31 kDa protein which, by the electrospray quadrupole time of flight mass spectrometry (ESI-Qtof-MS) analysis, showed homology to dirigent-like proteins known for assisting in radical coupling and polymerization of phenolic compounds. These findings provide a new look on protein-polyphenol interaction in honey where the reaction of quinones

  9. Army 86 Cost Sensitivity Analysis.

    DTIC Science & Technology

    1980-05-01

    NI VI AN/PVS-4 W/IMG 5 Q15414 RADAR ST AN/MPQ-4A LP 25 Q16110 RADAR SET AN/PPS- SALP 773 Q34308 RADIO SET AN/GRC-160 191 Q45779 RADIO SET AN/VRC-12 654...VI AN/PVS-4 W/ING 5 Q15414 RADAR ST AN/MPQ-4A LP 25 Q16110 RADAR SET AN/PPS- SALP 592 Q34308 RADIO SET AN/GRC-160 555 Q38299 RADIO SET AN/PRC-25 474...PVS-4 W/IMG Q15414 RADAR ST AN/MPQ-4A LP Q16110 RADAR SET AN/PPS- SALP Q34308 RADIO SET AN/GRC-160 Q38299 RADIO SET AN/PRC-25 Q45779 RADIO SET AN/VRC-12

  10. Crystallization and preliminary X-ray crystallographic analysis of two vascular apoptosis-inducing proteins (VAPs) from Crotalus atrox venom

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Igarashi, Tomoko; Oishi, Yuko; Araki, Satohiko

    Vascular apoptosis-inducing protein 1 (VAP1) and VAP2 from C. atrox venom were crystallized in variety of different crystal forms. Diffraction data sets were obtained to 2.5 and 2.15 Å resolution for VAP1 and VAP2, respectively. VAPs are haemorrhagic snake-venom toxins belonging to the reprolysin family of zinc metalloproteinases. In vitro, VAPs induce apoptosis specifically in cultured vascular endothelial cells. VAPs have a modular structure that bears structural homology to mammalian ADAMs (a disintegrin and metalloproteinases). VAP1 is a homodimer with a MW of 110 kDa in which the monomers are connected by a single disulfide bridge. VAP2 is homologous tomore » VAP1 and exists as a monomer with a MW of 55 kDa. In the current study, several crystal forms of VAP1 and VAP2 were obtained using the vapour-diffusion method and diffraction data sets were collected using SPring-8 beamlines. The best crystals of VAP1 and VAP2 generated data sets to 2.5 and 2.15 Å resolution, respectively.« less

  11. Detection of antigenic proteins expressed by lymphocystis virus as vaccine candidates in olive flounder, Paralichthys olivaceus (Temminck & Schlegel).

    PubMed

    Jang, H B; Kim, Y R; Cha, I S; Noh, S W; Park, S B; Ohtani, M; Hikima, J; Aoki, T; Jung, T S

    2011-07-01

    Although the major capsid proteins (MCPs) of lymphocystis disease virus (LCDV) have been characterized, little is known about the host-derived immune response to MCPs and other LCDV antigenic proteins. To identify antigenic proteins of LCDV that could be used as vaccine candidates in olive flounder, Paralichthys olivaceus, we analysed the viral proteins responsible for its virulence by applying immuno-proteomics. LCDV proteins were separated by one-dimensional gel electrophoresis, transferred to polyvinylidene difluoride membrane, and probed with homogeneous P. olivaceus antisera elicited by LCDV natural infection and vaccination with formalin-killed LCDV. Four immune-reactive proteins were obtained at 68-, 51-, 41- and 21 kDa using antisera collected from natural infection while two proteins at 51- and 21 kDa exhibited response to antisera from vaccinated fish, indicating that the latter two proteins have vaccine potential. Using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and nanoelectrospray MS/MS, the 51 and 21 kDa proteins were identified as MCP and an unknown protein, respectively. © 2011 Blackwell Publishing Ltd.

  12. Effect of protein supplementation on expression and distribution of urea transporter-B in lambs fed low-quality forage.

    PubMed

    Ludden, P A; Stohrer, R M; Austin, K J; Atkinson, R L; Belden, E L; Harlow, H J

    2009-04-01

    Two experiments were conducted to determine the effects of ruminal protein degradability, supplementation frequency, and increasing dietary protein on the expression and distribution of urea transporter-B (UT-B) in lambs fed low-quality forage (mature crested wheatgrass hay; 4.2 to 4.7% CP). In Exp. 1, 15 Dorset wether lambs (initial BW=45.8+/-1.3 kg) were blocked by initial BW and assigned to 1 of 3 treatments within a randomized complete block design for 28 d, with supplements fed to achieve 7, 10, or 13% total dietary CP. In Exp. 2, 13 Dorset wether lambs (initial BW=34+/-4 kg) were used in a completely randomized design and given 1 of 4 isonitrogenous supplements: 1) ruminally degradable protein (RDP) fed daily (n=3), 2) RDP fed on alternate days (n=3), 3) ruminally undegradable protein (RUP) fed on alternate days (n=3), or 4) a 50:50 mixture of RDP and RUP fed on alternate days (n=4) for 18 d. Alternate-day treatments were fed at twice that of daily supplementation. On the last day of both experiments, lambs were killed and samples taken for Western blot analyses for UT-B. Immunoblotting using a rabbit polyclonal antibody to UT-B confirmed the presence of distinct 32-kDa (consistent with a nonglycosylated UT-B protein) and 47-kDa (probable N-glycosylated form of UT-B) protein bands in all 9 tissues analyzed. In both experiments, the liver, dorsal rumen, reticulum, and ventral rumen displayed strong bands at 32 kDa and lighter bands at 47 kDa, whereas the cecum, large colon, spiral colon, and parotid salivary gland displayed slight 32-kDa bands and stronger, more visible bands at 47 kDa. Both protein bands were apparent in the kidney at similar visual intensities in Exp. 1, whereas the relative intensities of the 2 UT-B bands in the kidney were variable, and appeared somewhat reciprocal among animals in Exp. 2. Although the abundance of the 47-kDa UT-B band in the ventral rumen was greater (P=0.03) in lambs fed RDP daily in Exp. 2, no other treatment

  13. Abscisic acid activates a Ca2+-calmodulin-stimulated protein kinase involved in antioxidant defense in maize leaves.

    PubMed

    Xu, Shucheng

    2010-09-01

    The role of a calcium-dependent and calmodulin (CaM)-stimulated protein kinase in abscisic acid (ABA)-induced antioxidant defense was determined in leaves of maize (Zea mays). In-gel kinase assays showed that treatments with ABA or H(2)O(2) induced the activation of a 49-kDa protein kinase and a 52-kDa protein kinase significantly. Furthermore, we showed that the 52-kDa protein kinase has the characteristics of CaM-stimulating activity and is sensitive to calcium-CaM-dependent protein kinase II (CaMK II) inhibitor KN-93 or CaM antagonist W-7. Treatments with ABA or H(2)O(2) not only induced the activation of the 52-kDa protein kinase, but also enhanced the total activities of the antioxidant enzymes, including catalase, ascorbate peroxidase, glutathione reductase, and superoxide dismutase. Such enhancements were blocked by pretreatment with a CaMK inhibitor and a reactive oxygen species (ROS) inhibitor or scavenger. Pretreatment with the CaMK inhibitor also substantially arrested the ABA-induced H(2)O(2) production. Kinase activity enhancements induced by ABA were attenuated by pretreatment with an ROS inhibitor or scavenger. These results suggest that the 52-kDa CaMK is involved in ABA-induced antioxidant defense and that cross-talk between CaMK and H(2)O(2) plays a pivotal role in ABA signaling. We infer that CaMK acts both upstream and downstream of H(2)O(2), but mainly acts between ABA and H(2)O(2) in ABA-induced antioxidant-defensive signaling.

  14. The Use of Protein-Protein Interactions for the Analysis of the Associations between PM2.5 and Some Diseases.

    PubMed

    Zhang, Qing; Zhang, Pei-Wei; Cai, Yu-Dong

    2016-01-01

    Nowadays, pollution levels are rapidly increasing all over the world. One of the most important pollutants is PM2.5. It is known that the pollution environment may cause several problems, such as greenhouse effect and acid rain. Among them, the most important problem is that pollutants can induce a number of serious diseases. Some studies have reported that PM2.5 is an important etiologic factor for lung cancer. In this study, we extensively investigate the associations between PM2.5 and 22 disease classes recommended by Goh et al., such as respiratory diseases, cardiovascular diseases, and gastrointestinal diseases. The protein-protein interactions were used to measure the linkage between disease genes and genes that have been reported to be modulated by PM2.5. The results suggest that some diseases, such as diseases related to ear, nose, and throat and gastrointestinal, nutritional, renal, and cardiovascular diseases, are influenced by PM2.5 and some evidences were provided to confirm our results. For example, a total of 18 genes related to cardiovascular diseases are identified to be closely related to PM2.5, and cardiovascular disease relevant gene DSP is significantly related to PM2.5 gene JUP.

  15. Changes in NGF and NT-3 protein species in the superior cervical ganglion following axotomy of postganglionic axons.

    PubMed

    Walker, Ryan G; Foster, Andrew; Randolph, Chris L; Isaacson, Lori G

    2009-02-19

    Mature sympathetic neurons in the superior cervical ganglion (SCG) are regulated by target-derived neurotrophins such as nerve growth factor (NGF) and neurotrophin-3 (NT-3). High molecular weight NGF species and mature NT-3 are the predominant NGF and NT-3 protein isoforms in the SCG, yet it is unknown whether the presence of these species is dependent on intact connection with the target tissues. In an attempt to determine the role of peripheral targets in regulating the neurotrophin species found in the SCG, we investigated the NGF and NT-3 protein species present in the SCG following axotomy (transection) or injury of the post-ganglionic axons. Following a 7 day axotomy, the 22-24 kDa NGF species and the mature 14 kDa NT-3 species in the SCG were significantly reduced by 99% and 66% respectively, suggesting that intact connection with the target is necessary for the expression of these protein species. As expected, tyrosine hydroxylase (TH) protein in the SCG was significantly reduced by 80% at 7 days following axotomy. In order to distinguish between the effects of injury and loss of target connectivity, the SCG was examined following compression injury to the post-ganglionic nerves. Following injury, no reduction in the 22-24 kDa NGF or 14 kDa mature NT-3 species was observed in the SCG. TH protein was slightly, yet significantly, decreased in the SCG following injury. The findings of this study suggest that the presence of the 22-24 kDa NGF and mature 14 kDa NT-3 species in the SCG is dependent on connection with peripheral targets and may influence, at least in part, TH protein expression in adult sympathetic neurons.

  16. T-cell epitope analysis using subtracted expression libraries (TEASEL): application to a 38-kDA autoantigen recognized by T cells from an insulin-dependent diabetic patient.

    PubMed Central

    Neophytou, P I; Roep, B O; Arden, S D; Muir, E M; Duinkerken, G; Kallan, A; de Vries, R R; Hutton, J C

    1996-01-01

    Studies on circulating T cells and antibodies in newly diagnosed type 1 diabetic patients and rodent models of autoimmune diabetes suggest that beta-cell membrane proteins of 38 kDa may be important molecular targets of autoimmune attack. Biochemical approaches to the isolation and identification of the 38-kDa autoantigen have been hampered by the restricted availability of islet tissue and the low abundance of the protein. A procedure of epitope analysis for CD4+ T cells using subtracted expression libraries (TEASEL) was developed and used to clone a 70-amino acid pancreatic beta-cell peptide incorporating an epitope recognized by a 38-kDa-reactive CD4+ T-cell clone (1C6) isolated from a human diabetic patient. The minimal epitope was mapped to a 10-amino acid synthetic peptide containing a DR1 consensus binding motif. Data base searches did not reveal the identity of the protein, though a weak homology to the bacterial superantigens SEA (Streptococcus pyogenes exotoxin A) and SEB (Staphylococcus aureus enterotoxin B) (23% identity) was evident. The TEASEL procedure might be used to identify epitopes of other autoantigens recognized by CD4+ T cells in diabetes as well as be more generally applicable to the study low-abundance autoantigens in other tissue-specific autoimmune diseases. PMID:8700877

  17. Genetic diversity of functional food species Spinacia oleracea L. by protein markers.

    PubMed

    Rashid, M; Yousaf, Z; Haider, M S; Khalid, S; Rehman, H A; Younas, A; Arif, A

    2014-01-01

    Exploration of genetic diversity contributes primarily towards crop improvement. Spinaciaoleracea L. is a functional food species but unfortunately the genetic diversity of this vegetable is still unexplored. Therefore, this research was planned to explore the genetic diversity of S. oleracea by using morphological and protein markers. Protein profile of 25 accessions was generated on sodium dodecyl sulphate polyacrylamide gel. Total allelic variation of 27 bands was found. Out of these, 20 were polymorphic and the rest of the bands were monomorphic. Molecular weights of the bands ranged from 12.6 to 91.2 kDa. Major genetic differences were observed in accession 20541 (Peshawar) followed by 20180 (Lahore) and 19902 (AVRDC). Significant differences exist in the protein banding pattern. This variation can further be studied by advanced molecular techniques, including two-dimensional electrophoresis and DNA markers.

  18. Biochemistry of plant class IV chitinases and fungal chitinase-modifying proteins

    USDA-ARS?s Scientific Manuscript database

    Plant class IV chitinases have 2 domains, a small (3 kDa) amino-terminal domain with homology to carbohydrate binding peptides, and a larger (25 kDa) catalytic domain. The biological function of these chitinases is not known. But it is known that some pathogenic fungi secrete chitinase modifying pro...

  19. Starch and protein analysis of wheat bread enriched with phenolics-rich sprouted wheat flour.

    PubMed

    Świeca, Michał; Dziki, Dariusz; Gawlik-Dziki, Urszula

    2017-08-01

    Wheat flour in the bread formula was replaced with sprouted wheat flour (SF) characterized by enhanced nutraceutical properties, at 5%, 10%, 15% and 20% levels. The addition of SF slightly increased the total protein content; however, it decreased their digestibility. Some qualitative and quantitative changes in the electrophoretic pattern of proteins were also observed; especially, in the bands corresponding with 27kDa and 15-17kDa proteins. These results were also confirmed by SE-HPLC technique, where a significant increase in the content of proteins and peptides (molecular masses <20kDa) was determined for breads with 20% of SF. Bread enriched with sprouted wheat flour had more resistant starch, but less total starch, compared to control bread. The highest in vitro starch digestibility was determined for the control bread. The studied bread with lowered nutritional value but increased nutritional quality can be used for special groups of consumers (obese, diabetic). Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. An endogenous 55 kDa TNF receptor mediates cell death in a neural cell line.

    PubMed

    Sipe, K J; Srisawasdi, D; Dantzer, R; Kelley, K W; Weyhenmeyer, J A

    1996-06-01

    Tumor necrosis factor-alpha (TNF) is associated with developmental and injury-related events in the central nervous system (CNS). In the present study, we have examined the role of TNF on neurons using the clonal murine neuroblastoma line, N1E-115 (N1E). N1E cells represent a well-defined model for studying neuronal development since they can be maintained as either undifferentiated, mitotically active neuroblasts or as differentiated, mature neurons. Northern and reverse transcription-polymerase chain reaction (RT-PCR) analyses revealed that both undifferentiated and differentiated N1Es express transcripts for the 55 kDa TNF receptor (TNFR), but not the 75 kDa TNFR. The biological activity of the expressed TNF receptor was demonstrated by a dose dependent cytotoxicity to either recombinant murine or human TNF when the cells were incubated with the transcriptional inhibitor actinomycin D. The lack of the 75 kDa receptor mRNA expression and the dose dependent response to rHuTNF, an agonist specific for the murine 55 kDa receptor, suggest that the TNF induced cytotoxicity is mediated through the 55 kDa receptor in both the undifferentiated and differentiated N1Es. Light microscopic observations, flow cytometric analysis of hypodiploid DNA, and electrophoretic analysis of nucleosomal DNA fragmentation of N1Es treated with actinomycin D and TNF revealed features characteristic of both necrotic and apoptotic cell death. These findings demonstrate that blast and mature N1E cells express the 55 kDa TNF receptor which is responsible for inducing both necrotic and apoptotic death in these cells. The observation that actinomycin D renders N1E cells susceptible to the cytotoxic effects of TNF indicates that a sensitization step, such as removal of an endogenous protective factor or viral-mediated inhibition of transcription, may be necessary for TNF cytotoxicity in neurons.

  1. Comparative studies of lepidopteran baculovirus-specific protein FP25K: development of a novel Bombyx mori nucleopolyhedrovirus-based vector with a modified fp25K gene.

    PubMed

    Nakanishi, Tadashi; Goto, Chie; Kobayashi, Michihiro; Kang, Wonkyung; Suzuki, Takehiro; Dohmae, Naoshi; Matsumoto, Shogo; Shimada, Toru; Katsuma, Susumu

    2010-05-01

    Lepidopteran baculovirus-specific protein FP25K performs many roles during the infection cycle, including functions in the production of occlusion bodies (OBs) and budded viruses (BVs), oral infection, and postmortem host degradation. To explore the common and specific functions of FP25K proteins among lepidopteran baculoviruses, we performed comparative analyses of FP25K proteins from group I and group II nucleopolyhedroviruses (NPVs) and granulovirus (GV). Using recombinant Bombyx mori NPVs (BmNPVs), we showed that the FP25Ks from NPVs were able to eliminate all the phenotypic defects observed in an infection with a BmNPV mutant lacking functional fp25K but that FP25K from GV did not show abilities to recover oral infectivity and postmortem host degradation. We also observed that introduction of Autographa californica multiple NPV (AcMNPV) fp25K into the BmNPV genome enhanced OB and BV production. According to these results, we generated a novel BmNPV-based expression vector with AcMNPV fp25K and examined its potential in BmN cells and B. mori larvae. Our results showed that the introduction of AcMNPV fp25K significantly increases the expression of foreign gene products in cultured cells and shortens the time for obtaining the secreted recombinant proteins from larval hemolymph.

  2. Small peptides patterned after the N-terminus domain of SNAP25 inhibit SNARE complex assembly and regulated exocytosis.

    PubMed

    Blanes-Mira, Clara; Merino, Jaime M; Valera, Elvira; Fernández-Ballester, Gregorio; Gutiérrez, Luis M; Viniegra, Salvador; Pérez-Payá, Enrique; Ferrer-Montiel, Antonio

    2004-01-01

    Synthetic peptides patterned after the C-terminus of synaptosomal associated protein of 25 kDa (SNAP25) efficiently abrogate regulated exocytosis. In contrast, the use of SNAP25 N-terminal-derived peptides to modulate SNAP receptors (SNARE) complex assembly and neurosecretion has not been explored. Here, we show that the N-terminus of SNAP25, specially the segment that encompasses 22Ala-44Ile, is essential for the formation of the SNARE complex. Peptides patterned after this protein domain are potent inhibitors of SNARE complex formation. The inhibitory activity correlated with their propensity to adopt an alpha-helical secondary structure. These peptides abrogated SNARE complex formation only when added previous to the onset of aggregate assembly. Analysis of the mechanism of action revealed that these peptides disrupted the binary complex formed by SNAP25 and syntaxin. The identified peptides inhibited Ca2+-dependent exocytosis from detergent-permeabilized excitable cells. Noteworthy, these amino acid sequences markedly protected intact hippocampal neurones against hypoglycaemia-induced, glutamate-mediated excitotoxicity with a potency that rivalled that displayed by botulinum neurotoxins. Our findings indicate that peptides patterned after the N-terminus of SNAP25 are potent inhibitors of SNARE complex formation and neuronal exocytosis. Because of their activity in intact neurones, these cell permeable peptides may be hits for antispasmodic and analgesic drug development.

  3. A Mechanistic and Structural Analysis of the Inhibition of the 90-kDa Heat Shock Protein by the Benzoquinone and Hydroquinone AnsamycinsS⃞

    PubMed Central

    Reigan, Philip; Siegel, David; Guo, Wenchang

    2011-01-01

    The benzoquinone ansamycins inhibit the ATPase activity of the 90-kDa heat shock protein (Hsp90), disrupting the function of numerous client proteins involved in oncogenesis. In this study, we examine the role of NAD(P)H:quinone oxidoreductase 1 (NQO1) in the metabolism of trans- and cis-amide isomers of the benzoquinone ansamycins and their mechanism of Hsp90 inhibition. Inhibition of purified human Hsp90 by a series of benzoquinone ansamycins was examined in the presence and absence of NQO1, and their relative rate of NQO1-mediated reduction was determined. Computational-based molecular docking simulations indicated that the trans- but not the cis-amide isomers of the benzoquinone ansamycins could be accommodated by the NQO1 active site, and the ranking order of binding energies correlated with the relative reduction rate using purified human NQO1. The trans-cis isomerization of the benzoquinone ansamycins in Hsp90 inhibition has been disputed in recent reports. Previous computational studies have used the closed or cocrystallized Hsp90 structures in an attempt to explore this isomerization step; however, we have successfully docked both the trans- and cis-amide isomers of the benzoquinone ansamycins into the open Hsp90 structure. The results of these studies indicate that both trans- and cis-amide isomers of the hydroquinone ansamycins exhibited increased binding affinity for Hsp90 relative to their parent quinones. Our data support a mechanism in which trans- rather than cis-amide forms of benzoquinone ansamycins are metabolized by NQO1 to hydroquinone ansamycins and that Hsp90-mediated trans-cis isomerization via tautomerization plays an important role in subsequent Hsp90 inhibition. PMID:21285336

  4. Yolk proteins during ovary and egg development of mature female freshwater crayfish (Cherax quadricarinatus).

    PubMed

    Serrano-Pinto, Vania; Vazquez-Boucard, Celia; Villarreal-Colmenares, Humberto

    2003-01-01

    Vitellins from ovaries and eggs at different stages of development in freshwater crayfish (Cherax quadricarinatus) were examined by chromatography, PAGE and SDS-PAGE. With these methods, two forms of vitellin (Vt1 and Vt2) were observed in ovaries and eggs (stages I and V). In ovaries in secondary vitellogenesis, native molecular mass was 470 (Vt1) and 440 (Vt2) kDa. The electrophoretic pattern of the eggs proved to be more complex. The protein molecular mass depend on the development stage of the egg: stage I, 650 kDa (Vt1) and 440 kDa (Vt2); stage V, 390 kDa (Vt1) and 340 kDa (Vt2). The identified vitellins appear to be lipo-glycocarotenoprotein. A similar vitellin polypeptide composition was observed in the two forms of vitellin from ovaries and eggs in stage V. In ovaries the SDS-PAGE analysis showed four subunits with molecular weights of approximately 180, 120, 95 and 80 kDa (Vt1 and Vt2). The polypeptide composition in the two forms of vitellins in stage I and stage III eggs were different at 195, 190, 130 and 110 kDa (Vt1) and 116 and 107 kDa (Vt2). On the other hand, in stage V eggs, 110, 95, 87 and 75 kDa (Vt1 and Vt2) were identified. Two antibodies (Ab1 and Ab2) were prepared against the purified proteins of stage V eggs and their specificity was demonstrated by radial immunoprecipitation, and Western blotting analysis. Two forms of vitellins were also found in stage V eggs after chromatography on Sepharose CL-2B column and hydroxylapatite and polyacrylamide gel electrophoresis.

  5. A Novel Helicase-Type Protein in the Nucleolus: Protein NOH61

    PubMed Central

    Zirwes, Rudolf F.; Eilbracht, Jens; Kneissel, Sandra; Schmidt-Zachmann, Marion S.

    2000-01-01

    We report the identification, cDNA cloning, and molecular characterization of a novel, constitutive nucleolar protein. The cDNA-deduced amino acid sequence of the human protein defines a polypeptide of a calculated mass of 61.5 kDa and an isoelectric point of 9.9. Inspection of the primary sequence disclosed that the protein is a member of the family of “DEAD-box” proteins, representing a subgroup of putative ATP-dependent RNA helicases. ATPase activity of the recombinant protein is evident and stimulated by a variety of polynucleotides tested. Immunolocalization studies revealed that protein NOH61 (nucleolar helicase of 61 kDa) is highly conserved during evolution and shows a strong accumulation in nucleoli. Biochemical experiments have shown that protein NOH61 synthesized in vitro sediments with ∼11.5 S, i.e., apparently as homo-oligomeric structures. By contrast, sucrose gradient centrifugation analysis of cellular extracts obtained with buffers of elevated ionic strength (600 mM NaCl) revealed that the solubilized native protein sediments with ∼4 S, suggestive of the monomeric form. Interestingly, protein NOH61 has also been identified as a specific constituent of free nucleoplasmic 65S preribosomal particles but is absent from cytoplasmic ribosomes. Treatment of cultured cells with 1) the transcription inhibitor actinomycin D and 2) RNase A results in a complete dissociation of NOH61 from nucleolar structures. The specific intracellular localization and its striking sequence homology to other known RNA helicases lead to the hypothesis that protein NOH61 might be involved in ribosome synthesis, most likely during the assembly process of the large (60S) ribosomal subunit. PMID:10749921

  6. Identification of three proteins in the eye of Aplysia, whose synthesis is altered by serotonin (5-HT). Possible involvement of these proteins in the ocular circadian system.

    PubMed

    Koumenis, C; Nunez-Regueiro, M; Raju, U; Cook, R; Eskin, A

    1995-06-16

    Previous results using translation inhibitors in the ocular circadian system of Aplysia suggest that protein synthesis may be involved in the light and serotonin (5-HT) entrainment pathways or perhaps in the circadian oscillator. Proteins have been previously identified whose synthesis was altered by treatments of light capable of perturbing the phase of the circadian rhythm in the eye of Aplysia. We extended these studies by investigating the effects of other treatments that perturb the ocular circadian rhythm on protein synthesis. 5-HT altered the synthesis of nine proteins. Interestingly, five of the proteins affected by treatments with 5-HT were previously shown to be affected by treatments with light. Four of the proteins affected by treatments with 5-HT were also affected by treatments with analogs of cAMP, a treatment which mimics the effects of 5-HT on the ocular circadian rhythm. To identify the cellular function of some of these proteins, we obtained their partial amino acid sequences. Based on these sequences and additional characterizations, a 78-kDa, pI 5.6 Aplysia protein appears to be glucose-regulated protein 78/binding protein, and a 36-kDa, pI 5.7 Aplysia protein appears to be porin/voltage-dependent anion channel. Heat shock experiments on Aplysia eyes revealed that yet another one of the Aplysia proteins (70 kDa) affected by 5-HT appears to be a heat-inducible member (heat shock protein 70) of the family of heat shock proteins. These findings suggest that these three identified proteins, together or individually, may be involved in some way in the regulation of the timing of the circadian oscillator in the eye of Aplysia.

  7. Cadmium inhibits mouse sperm motility through inducing tyrosine phosphorylation in a specific subset of proteins.

    PubMed

    Wang, Lirui; Li, Yuhua; Fu, Jieli; Zhen, Linqing; Zhao, Na; Yang, Qiangzhen; Li, Sisi; Li, Xinhong

    2016-08-01

    Cadmium (Cd) has been reported to impair male fertility, primarily by disrupting sperm motility, but the underlying molecular mechanism remains unclear. Here we investigated the effects of Cd on sperm motility, tyrosine phosphorylation, AMP-activated protein kinase (AMPK) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity, and ATP levels in vitro. Our results demonstrated that Cd inhibited sperm motility, GAPDH activity, AMPK activity and ATP production, and induced tyrosine phosphorylation of 55-57KDa proteins. Importantly, all the parameters affected by Cd were restored to normal levels when incubated with 10μM Cd in the presence of 30μM ethylene diamine tetraacetic acid (EDTA). Interestingly, changes of tyrosine phosphorylation levels of 55-57KDa proteins are completely contrary to that of other parameters. These results suggest that Cd-induced tyrosine phosphorylation of 55-57KDa proteins might act as an engine to block intracellular energy metabolism and thus decrease sperm motility. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. A cell wall protein-based vaccine candidate induce protective immune response against Sporothrix schenckii infection.

    PubMed

    Portuondo, Deivys Leandro; Batista-Duharte, Alexander; Ferreira, Lucas Souza; Martínez, Damiana Téllez; Polesi, Marisa Campos; Duarte, Roberta Aparecida; de Paula E Silva, Ana Carolina Alves; Marcos, Caroline Maria; Almeida, Ana Marisa Fusco de; Carlos, Iracilda Zeppone

    2016-02-01

    Sporotrichosis is a subcutaneous mycosis caused by several closely related thermo-dimorphic fungi of the Sporothrix schenckii species complex, affecting humans and other mammals. In the last few years, new strategies have been proposed for controlling sporotrichosis owning to concerns about its growing incidence in humans, cats, and dogs in Brazil, as well as the toxicity and limited efficacy of conventional antifungal drugs. In this study, we assessed the immunogenicity and protective properties of two aluminum hydroxide (AH)-adsorbed S. schenckii cell wall protein (ssCWP)-based vaccine formulations in a mouse model of systemic S. schenckii infection. Fractioning by SDS-PAGE revealed nine protein bands, two of which were functionally characterized: a 44kDa peptide hydrolase and a 47kDa enolase, which was predicted to be an adhesin. Sera from immunized mice recognized the 47kDa enolase and another unidentified 71kDa protein, whereas serum from S. schenckii-infected mice recognized both these proteins plus another unidentified 9.4kDa protein. Furthermore, opsonization with the anti-ssCWP sera led to markedly increased phagocytosis and was able to strongly inhibit the fungus' adhesion to fibroblasts. Immunization with the higher-dose AH-adjuvanted formulation led to increased ex vivo release of IL-12, IFN-γ, IL-4, and IL-17, whereas only IL-12 and IFN-γ were induced by the higher-dose non-adjuvanted formulation. Lastly, passive transference of the higher-dose AH-adjuvanted formulation's anti-ssCWP serum was able to afford in vivo protection in a subsequent challenge with S. schenckii, becoming a viable vaccine candidate for further testing. Copyright © 2015 Elsevier GmbH. All rights reserved.

  9. Experimental Protein Structure Verification by Scoring with a Single, Unassigned NMR Spectrum

    PubMed Central

    Courtney, Joseph M.; Ye, Qing; Nesbitt, Anna E.; Tang, Ming; Tuttle, Marcus D.; Watt, Eric D.; Nuzzio, Kristin M.; Sperling, Lindsay J.; Comellas, Gemma; Peterson, Joseph R.; Morrissey, James H.; Rienstra, Chad M.

    2016-01-01

    Standard methods for de novo protein structure determination by nuclear magnetic resonance (NMR) require time-consuming data collection and interpretation efforts. Here we present a qualitatively distinct and novel approach, called Comparative, Objective Measurement of Protein Architectures by Scoring Shifts (COMPASS), which identifies the best structures from a set of structural models by numerical comparison with a single, unassigned 2D 13C-13C NMR spectrum containing backbone and side-chain aliphatic signals. COMPASS does not require resonance assignments. It is particularly well suited for interpretation of magic-angle spinning solid-state NMR spectra, but also applicable to solution NMR spectra. We demonstrate COMPASS with experimental data from four proteins—GB1, ubiquitin, DsbA, and the extracellular domain of human tissue factor—and with reconstructed spectra from 11 additional proteins. For all these proteins, with molecular mass up to 25 kDa, COMPASS distinguished the correct fold, most often within 1.5 Å root-mean-square deviation of the reference structure. PMID:26365800

  10. Palisade endings in extraocular eye muscles revealed by SNAP-25 immunoreactivity.

    PubMed

    Eberhorn, Andreas C; Horn, Anja K E; Eberhorn, Nicola; Fischer, Petra; Boergen, Klaus-Peter; Büttner-Ennever, Jean A

    2005-03-01

    Palisade endings form a cuff of nerve terminals around the tip of muscle fibres. They are found only in extraocular muscles, but no definite evidence for their role in eye movements has been established. Palisade endings have been reported in all species so far investigated except the rat. In this study we demonstrate that antibodies against SNAP-25, the synaptosomal associated protein of 25 kDa, reliably visualize the complete motor, sensory and autonomic innervation of the extraocular muscles in human, monkey and rat. The SNAP-25 antibody can be combined with other immunofluorescence procedures, and is used here to study properties of palisade endings. With SNAP-25 immunolabelling putative palisade endings are identified in the rat for the first time. They are not well branched, but fulfil several criteria of palisade endings, being associated with non-twitch fibres as shown by double labelling with 'myosin heavy chain slow-twitch' antibodies. The putative palisade endings of the rat lack alpha-bungarotoxin binding, which implies that these synapses are sensory. If palisade endings are sensory then they could function as an eye muscle proprioceptor. They seem to be a general feature of all vertebrate eye muscles, unlike the other two extraocular proprioceptors, muscle spindles and Golgi tendon organs, the presence of which varies widely between species.

  11. Protein modification in the post-mating spermatophore of the signal crayfish Pacifastacus leniusculus: insight into the tyrosine phosphorylation in a non-motile spermatozoon.

    PubMed

    Niksirat, Hamid; Vancová, Marie; Andersson, Liselotte; James, Peter; Kouba, Antonín; Kozák, Pavel

    2016-09-01

    After mating, spermatophores of signal crayfish are stored on the body of the female for a period before fertilization. This study compared the post-mating protein profile and pattern of protein tyrosine phosphorylation of the signal crayfish spermatophore to that of the freshly ejaculated spermatophore and found substantial differences. Two major bands of tyrosine-phosphorylated proteins of molecular weights 10 and 50kDa were observed in the freshly ejaculated spermatophore of the signal crayfish. While the tyrosine-phosphorylated protein band with molecular weight 10kDa was formed by protein(s) of similar pH, the band with molecular weight of 50kDa consisted of proteins of varying pH. In the post-mating spermatophore, the band with molecular weight of 50kDa was not detected, and an increase in the level of protein tyrosine phosphorylation was observed in the 10kDa band. The microtubular radial arms of the spermatozoon showed a positive reaction to an anti-tyrosine antibody conjugated with gold particles in both the freshly ejaculated and post-mating spermatophores. In conclusion, the male gamete of the signal crayfish undergoes molecular modification during post-mating storage on the body of the female including changes in the level of protein expression and protein tyrosine phosphorylation. Structural similarity of the radial arms in the crayfish immotile spermatozoon with flagellum, which is the main site of protein tyrosine phosphorylation in the mammalian motile spermatozoa, raises questions regarding evolution and function of such organelles across the animal kingdom that must be addressed in the future studies. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Silencing the hsp25 gene eliminates migration capability of the highly metastatic murine 4T1 breast adenocarcinoma cell.

    PubMed

    Bausero, Maria A; Bharti, Ajit; Page, Diana T; Perez, Kristen D; Eng, Jason W-L; Ordonez, Susana L; Asea, Edwina E; Jantschitsch, Christian; Kindas-Muegge, Ingela; Ciocca, Daniel; Asea, Alexzander

    2006-01-01

    The 25-kDa heat shock protein (Hsp25) is associated with various malignancies and is expressed at high levels in biopsies as well as circulating in the serum of breast cancer patients. In this study, we used RNA interference technology to silence the hsp25 gene in 4T1 breast adenocarcinoma cells, known as a poorly immunogenic, highly metastatic cell line. We demonstrate that transfection of 4T1 cells with short interference RNA-Hsp25 dramatically inhibits proliferation as compared with control transfected cells. In addition, we show that 4T1 cells transfected with short interference RNA-Hsp25 abrogates tumor migration potential by a mechanism that is in part due to the repression of matrix metalloproteinase 9 expression and a concomitant upregulation of its antagonist, tissue inhibitor metalloproteinase 1. Taken together, these findings provide a model system for the study of metastatic potential of tumors and are suggestive of an earlier unrecognized role for Hsp25 in tumor migration. Copyright 2006 S. Karger AG, Basel.

  13. Studies of the viral binding proteins of shrimp BP53, a receptor of white spot syndrome virus.

    PubMed

    Li, Chen; Gao, Xiao-Xiao; Huang, Jie; Liang, Yan

    2016-02-01

    The specific binding between viral attachment proteins (VAPs) of a virus and its cellular receptors on host cells mediates virus entry into host cells, which triggers subsequent viral infections. Previous studies indicate that F1 ATP synthase β subunit (named BP53), is found on the surface of shrimp cells and involved in white spot syndrome virus (WSSV) infection by functioning as a potential viral receptor. Herein, in a far-western blotting assay, three WSSV proteins with molecular weights of 28 kDa, 37 kDa, and >50 kDa were found to interact with BP53. The 28 kDa and 37 kDa proteins were identified as the envelope protein VP28 and VP37 of WSSV respectively, which could be recognized by the polyclonal antibodies. Enzyme-linked immunosorbent binding assays revealed that VP37 contributed to almost 80% of the binding capability for BP53 compared with the same amount of total WSSV protein. The relationship between BP53 and its complementary interacting protein, VP37, was visualized using a co-localization assay. Bound VP37 on the cell surface co-localized with BP53 and shared a similar subcellular location on the outer surface of shrimp cells. Pearson's correlation coefficients reached to 0.67 ± 0.05 and the Mander's overlap coefficients reached 0.70 ± 0.05, which indicated a strong relationship between the localization of BP53 and bound rVP37. This provides evidence for an interaction between BP53 and VP37 obtained at the molecular and cellular levels, supporting the hypothesis that BP53 serves as a receptor for WSSV by binding to VP37. The identification of the viral binding proteins of shrimp BP53 is helpful for better understanding the pathogenic mechanisms of WSSV to infect shrimp at the cellular level. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Free 25-Hydroxyvitamin D: Impact of Vitamin D Binding Protein Assays on Racial-Genotypic Associations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nielson, Carrie M.; Jones, Kerry S.; Chun, Rene F.

    Total 25-hydroxyvitamin D (25OHD) is a marker of vitamin D status and is lower in African Americans than in whites. Whether this difference holds for free 25OHOD (f25OHD) is unclear, considering reported genetic-racial differences in vitaminDbinding protein (DBP) used to calculate f25OHD.

  15. Identification of a melanosomal membrane protein encoded by the pink-eyed dilution (type II oculocutaneous albinism) gene.

    PubMed Central

    Rosemblat, S; Durham-Pierre, D; Gardner, J M; Nakatsu, Y; Brilliant, M H; Orlow, S J

    1994-01-01

    The pink-eyed dilution (p) locus in the mouse is critical to melanogenesis; mutations in the homologous locus in humans, P, are a cause of type II oculocutaneous albinism. Although a cDNA encoded by the p gene has recently been identified, nothing is known about the protein product of this gene. To characterize the protein encoded by the p gene, we performed immunoblot analysis of extracts of melanocytes cultured from wild-type mice with an antiserum from rabbits immunized with a peptide corresponding to amino acids 285-298 of the predicted protein product of the murine p gene. This antiserum recognized a 110-kDa protein. The protein was absent from extracts of melanocytes cultured from mice with two mutations (pcp and p) in which transcripts of the p gene are absent or greatly reduced. Introduction of the cDNA for the p gene into pcp melanocytes by electroporation resulted in expression of the 3.3-kb mRNA and the 110-kDa protein. Upon subcellular fractionation of cultured melanocytes, the 110-kDa protein was found to be present in melanosomes but absent from the vesicular fraction; phase separation performed with the nonionic detergent Triton X-114 confirmed the predicted hydrophobic nature of the protein. These results demonstrate that the p gene encodes a 110-kDa integral melanosomal membrane protein and establish a framework by which mutations at this locus, which diminish pigmentation, can be analyzed at the cellular and biochemical levels. Images PMID:7991586

  16. HPV16 E7 protein associates with the protein kinase p33CDK2 and cyclin A.

    PubMed

    Tommasino, M; Adamczewski, J P; Carlotti, F; Barth, C F; Manetti, R; Contorni, M; Cavalieri, F; Hunt, T; Crawford, L

    1993-01-01

    E7 is the major transforming protein of human papillomavirus type 16 (HPV16). It has been found to associate with the retinoblastoma protein Rb1. We investigated whether HPV16 E7 protein was associated with other cellular proteins, in particular with those involved in cell cycle control. Immunoprecipitates from CaSki cell extracts with an anti E7 monoclonal antibody contained a histone H1 kinase. Recombinant E7, synthesized in yeast, when mixed with protein extracts from epithelial cells bound histone H1 kinase activity in vitro. The in vivo and the in vitro-formed E7-kinase complex had the same periodicity of activity during the cell cycle, being most active in S and G2/M. Immunoblotting of E7 immunoprecipitates with an antibody raised against the p33CDK2, revealed a 33 kDa protein band not detected by an anti-p34cdc2 antibody, suggesting that the E7-associated kinase activity is due to the p33CDK2. The interaction appears to be via cyclin A, since probing of similar immunoblots showed a 50 kDa band corresponding to cyclin A. The association of E7 with cyclin A appeared to be direct, not involving Rb 1 or other proteins.

  17. Optimization of NMR spectroscopy of encapsulated proteins dissolved in low viscosity fluids

    PubMed Central

    Nucci, Nathaniel V.; Marques, Bryan S.; Bédard, Sabrina; Dogan, Jakob; Gledhill, John M.; Moorman, Veronica R.; Peterson, Ronald W.; Valentine, Kathleen G.; Wand, Alison L.; Wand, A. Joshua

    2014-01-01

    Comprehensive application of solution NMR spectroscopy to studies of macromolecules remains fundamentally limited by the molecular rotational correlation time. For proteins, molecules larger than 30 kDa require complex experimental methods, such as TROSY in conjunction with isotopic labeling schemes that are often expensive and generally reduce the potential information available. We have developed the reverse micelle encapsulation strategy as an alternative approach. Encapsulation of proteins within the protective nano-scale water pool of a reverse micelle dissolved in ultra-low viscosity nonpolar solvents overcomes the slow tumbling problem presented by large proteins. Here, we characterize the contributions from the various components of the protein-containing reverse micelle system to the rotational correlation time of the encapsulated protein. Importantly, we demonstrate that the protein encapsulated in the reverse micelle maintains a hydration shell comparable in size to that seen in bulk solution. Using moderate pressures, encapsulation in ultra-low viscosity propane or ethane can be used to magnify this advantage. We show that encapsulation in liquid ethane can be used to reduce the tumbling time of the 43 kDa maltose binding protein from ~23 ns to ~10 ns. These conditions enable, for example, acquisition of TOCSY-type data resolved on the adjacent amide NH for the 42 kDa encapsulated maltose binding protein dissolved in liquid ethane, which is typically impossible for proteins of such size without use of extensive deuteration or the TROSY effect. PMID:21748265

  18. Fourier Transform-Ion Cyclotron Resonance Mass Spectrometry as a Platform for Characterizing Multimeric Membrane Protein Complexes

    NASA Astrophysics Data System (ADS)

    Lippens, Jennifer L.; Nshanian, Michael; Spahr, Chris; Egea, Pascal F.; Loo, Joseph A.; Campuzano, Iain D. G.

    2018-01-01

    Membrane protein characterization is consistently hampered by challenges with expression, purification, and solubilization. Among several biophysical techniques employed for their characterization, native-mass spectrometry (MS) has emerged as a powerful tool for the analysis of membrane proteins and complexes. Here, two MS platforms, the FT-ICR and Q-ToF, have been explored to analyze the homotetrameric water channel protein, AquaporinZ (AqpZ), under non-denaturing conditions. This 97 kDa membrane protein complex can be readily liberated from the octylglucoside (OG) detergent micelle under a range of instrument conditions on both MS platforms. Increasing the applied collision energy of the FT-ICR collision cell yielded varying degrees of tetramer (97 kDa) liberation from the OG micelles, as well as dissociation into the trimeric (72 kDa) and monomeric (24 kDa) substituents. Tandem-MS on the Q-ToF yielded higher intensity tetramer signal and, depending on the m/z region selected, the observed monomer signal varied in intensity. Precursor ion selection of an m/z range above the expected protein signal distribution, followed by mild collisional activation, is able to efficiently liberate AqpZ with a high S/N ratio. The tetrameric charge state distribution obtained on both instruments demonstrated superpositioning of multiple proteoforms due to varying degrees of N-terminal formylation. [Figure not available: see fulltext.

  19. Docking and molecular dynamics simulations of the Fyn-SH3 domain with free and phospholipid bilayer-associated 18.5-kDa myelin basic protein (MBP)-Insights into a noncanonical and fuzzy interaction.

    PubMed

    Bessonov, Kyrylo; Vassall, Kenrick A; Harauz, George

    2017-07-01

    The molecular details of the association between the human Fyn-SH3 domain, and the fragment of 18.5-kDa myelin basic protein (MBP) spanning residues S38-S107 (denoted as xα2-peptide, murine sequence numbering), were studied in silico via docking and molecular dynamics over 50-ns trajectories. The results show that interaction between the two proteins is energetically favorable and heavily dependent on the MBP proline-rich region (P93-P98) in both aqueous and membrane environments. In aqueous conditions, the xα2-peptide/Fyn-SH3 complex adopts a "sandwich"-like structure. In the membrane context, the xα2-peptide interacts with the Fyn-SH3 domain via the proline-rich region and the β-sheets of Fyn-SH3, with the latter wrapping around the proline-rich region in a form of a clip. Moreover, the simulations corroborate prior experimental evidence of the importance of upstream segments beyond the canonical SH3-ligand. This study thus provides a more-detailed glimpse into the context-dependent interaction dynamics and importance of the β-sheets in Fyn-SH3 and proline-rich region of MBP. Proteins 2017; 85:1336-1350. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  20. Comparison of extracellular protein profiles of seven serotypes of mutans streptococci grown under controlled conditions.

    PubMed

    Hardy, L N; Knox, K W; Brown, R A; Wicken, A J; Fitzgerald, R J

    1986-05-01

    Extracellular proteins produced by the four human commensal species of mutans streptococci were analysed. The organisms used were Streptococcus mutans, serotypes c, e and f, Streptococcus cricetus, serotype a, Streptococcus rattus, serotype b, and Streptococcus sobrinus, serotypes d and g. They were grown in continuous culture at different generation times and pH values in media containing either glucose or fructose to determine the extent of variation in extracellular protein production that could occur for an individual strain. The results for different organisms grown under the same conditions were then compared. The total amount of protein of molecular mass greater than or equal to 60 kDa varied considerably with the growth conditions and with the strain. Generally more protein was present at a higher pH, conditions under which the organisms also form more lipoteichoic acid. With respect to individual protein components SDS-PAGE proved better than isoelectric focusing for detecting phenotypic responses by a particular strain to environmental changes and differences between the different strains. Differences in the molecular masses of protein components were particularly pronounced in the regions designated P1 (185-200 kDa), P2 (130-155 kDa) and P3 (60-95 kDa). Every strain produced at least one component in the P1 region that cross-reacted with antiserum to the purified protein from S. mutans serotype c, a protein which is indistinguishable from antigens B and I/II. Two components in the P2 region were dominant in the case of S. cricetus and S. sobrinus strains and showed glucosyltransferase (GTF) activity. GTF activity was also detected in the P3 region, particularly with S. mutans strains.

  1. Electrophoresis characterisation of protein as a method to establish the entomological origin of stingless bee honeys.

    PubMed

    Ramón-Sierra, Jesús Manuel; Ruiz-Ruiz, Jorge Carlos; de la Luz Ortiz-Vázquez, Elizabeth

    2015-09-15

    Increasing production of stingless-bee honey and the prospect of broader marker for natural and organic products indicate the need to establish parameters to determinate the entomological origin and authenticity of honey. In this research, honeys of Apis mellifera, Melipona beecheii and Trigona spp. were collected in Yucatan, Mexico. Stingless-bee honeys contained more water and less total sugars and reducing sugars. SDS-PAGE patterns show distinctive bands for each kind of honey. The SDS-PAGE pattern of A. mellifera proteins honey showed three bands with molecular weights between 10.2 and 74.8kDa, there were five proteins bands in M. beecheii honey with molecular weights between 6.1 and 97.0kDa and nine for Trigona spp. proteins between 9.3 and 86.7kDa. Conventional physicochemical parameters along with electrophoresis profiles of stingless-bee honeys proteins could be an alternative for determination of entomological origin. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. 36 kDa glycoprotein isolated from Rhus verniciflua stokes inhibits G/GO-induced mitochondrial apoptotic signal pathways in BNL CL.2 cells.

    PubMed

    Lee, Sei-Jung; Oh, Phil-Sun; Lim, Kwang; Lim, Kye-Taek

    2005-12-01

    Rhus verniciflua Stokes is one of the medicinal plants traditionally used to heal and treat hepatic and inflammatory diseases. We found that a glycoprotein isolated from the fruit has a molecular weight of 36 kDa and consists of a carbohydrate component (38.75%) and a protein (61.25%), and that the glycoprotein has a strong scavenging activity against hydroxyl radicals without any pro-oxidant activity in the cell-free system. In glucose/glucose oxidase (G/GO)-induced BNL CL.2 cells, the results showed that Rhus verniciflua Stokes glycoprotein has dose-dependent blocking activities against G/GO-induced cytotoxicity and apoptosis, increasing the glutathione (GSH) peroxidase activity. In the activity of the mitochondrial apoptotic mediators (cytochrome c, caspases and poly(ADP-ribose)polymerase (PARP)), the glycoprotein (100 microg/ml) showed an inhibitory effect on cytochrome c release, caspase-9/3 activation, and PARP cleavage. Moreover, Rhus verniciflua Stokes glycoprotein has a stimulating effect on the nitric oxide production. Here, we speculate that this glycoprotein is one of the natural antioxidants and of the modulators of apoptotic signal pathways in BNL CL.2 cells.

  3. Protein hydrolysate of salted duck egg white as a substitute of phosphate and its effect on quality of Pacific white shrimp (Litopenaeus vannamei).

    PubMed

    Kaewmanee, Thammarat; Benjakul, Soottawat; Visessanguan, Wonnop

    2009-10-01

    Protein hydrolysate from salted egg white (PHSEW) with different degrees of hydrolysis (DH) (3%, 6%, and 9%) was produced using pepsin. Disappearance of proteins with molecular weight (MW) of 108 and 85 kDa with the concomitant formation of proteins with MW of 23, 20, 13, and 5 kDa was observed in PHSEW. The use of PHSEW for quality improvement of Pacific white shrimp (Litopenaeus vannamei) was investigated. Shrimp soaked in 4% NaCl containing 7% PHSEW and 2.5% mixed phosphates (0.625% sodium acid pyrophosphate [SAPP] and 1.875% tetrasodium pyrophosphate [TSPP]) had the highest cooking yield with the lowest cooking loss (P < 0.05), compared with shrimps with other treatments. Nevertheless, no difference in weight gain was obtained in comparison with those treated with 4% NaCl containing 3.5% mixed phosphate (P > 0.05). Cooked shrimp treated with 4% NaCl containing 7% PHSEW and 2.5% mixed phosphate or those treated with 4% NaCl containing 3.5% mixed phosphate had the higher score of appearance, texture, and overall likeness but less shear force, in comparison with the control (no treatment) (P < 0.05). Microstructure study revealed that muscle fibers of cooked shrimp from both treatments had the swollen fibrils and gaps, while the control had the swollen compact structure. Therefore, use of PHSEW could reduce phosphate residue in shrimps without an adverse effect on sensory properties.

  4. The Vibrio parahaemolyticus small RNA RyhB promotes production of the siderophore vibrioferrin by stabilizing the polycistronic mRNA.

    PubMed

    Tanabe, Tomotaka; Funahashi, Tatsuya; Nakao, Hiroshi; Maki, Jun; Yamamoto, Shigeo

    2013-08-01

    High-affinity iron acquisition in Vibrio parahaemolyticus is mediated by the cognate siderophore vibrioferrin. We have previously reported that the vibrioferrin biosynthesis operon (pvsOp) is regulated at the transcriptional level by the iron-responsive repressor Fur (T. Tanabe, T. Funahashi, H. Nakao, S. Miyoshi, S. Shinoda, and S. Yamamoto, J. Bacteriol. 185:6938-6949, 2003). In this study, we identified the Fur-regulated small RNA RyhB and the RNA chaperone Hfq protein as additional regulatory proteins of vibrioferrin biosynthesis. We found that vibrioferrin production was greatly impaired in both the ryhB and hfq deletion mutants, and a TargetRNA search (http://snowwhite.wellesley.edu/targetRNA/index2.html) revealed that the 5'-untranslated region of pvsOp mRNA (pvsOp 5'-UTR) contains a potential base-pairing region required for the formation of the RyhB-pvsOp 5'-UTR duplex. An electrophoresis mobility shift assay indicated that RyhB can directly bind to the pvsOp 5'-UTR with the aid of Hfq. Rifampin chase experiments indicated that the half-life of pvsOp mRNA in the ryhB and hfq mutants was approximately 3-fold shorter than that in the parental strain, suggesting that both RyhB and Hfq are engaged in the stabilization of pvsOp mRNA. Chrome azurol S assays followed by electrophoresis mobility shift assays and rifampin chase experiments carried out for mutant strains indicated that base pairing between RyhB and the pvsOp 5'-UTR results in an increase in the stability of pvsOp mRNA, thereby leading to the promotion of vibrioferrin production. It is unprecedented that RyhB confers increased stability on a polycistronic mRNA involved in siderophore biosynthesis as a direct target.

  5. The Vibrio parahaemolyticus Small RNA RyhB Promotes Production of the Siderophore Vibrioferrin by Stabilizing the Polycistronic mRNA

    PubMed Central

    Funahashi, Tatsuya; Nakao, Hiroshi; Maki, Jun; Yamamoto, Shigeo

    2013-01-01

    High-affinity iron acquisition in Vibrio parahaemolyticus is mediated by the cognate siderophore vibrioferrin. We have previously reported that the vibrioferrin biosynthesis operon (pvsOp) is regulated at the transcriptional level by the iron-responsive repressor Fur (T. Tanabe, T. Funahashi, H. Nakao, S. Miyoshi, S. Shinoda, and S. Yamamoto, J. Bacteriol. 185:6938–6949, 2003). In this study, we identified the Fur-regulated small RNA RyhB and the RNA chaperone Hfq protein as additional regulatory proteins of vibrioferrin biosynthesis. We found that vibrioferrin production was greatly impaired in both the ryhB and hfq deletion mutants, and a TargetRNA search (http://snowwhite.wellesley.edu/targetRNA/index2.html) revealed that the 5′-untranslated region of pvsOp mRNA (pvsOp 5′-UTR) contains a potential base-pairing region required for the formation of the RyhB-pvsOp 5′-UTR duplex. An electrophoresis mobility shift assay indicated that RyhB can directly bind to the pvsOp 5′-UTR with the aid of Hfq. Rifampin chase experiments indicated that the half-life of pvsOp mRNA in the ryhB and hfq mutants was approximately 3-fold shorter than that in the parental strain, suggesting that both RyhB and Hfq are engaged in the stabilization of pvsOp mRNA. Chrome azurol S assays followed by electrophoresis mobility shift assays and rifampin chase experiments carried out for mutant strains indicated that base pairing between RyhB and the pvsOp 5′-UTR results in an increase in the stability of pvsOp mRNA, thereby leading to the promotion of vibrioferrin production. It is unprecedented that RyhB confers increased stability on a polycistronic mRNA involved in siderophore biosynthesis as a direct target. PMID:23772063

  6. A New Look on Protein-Polyphenol Complexation during Honey Storage: Is This a Random or Organized Event with the Help of Dirigent-Like Proteins?

    PubMed Central

    Brudzynski, Katrina; Sjaarda, Calvin; Maldonado-Alvarez, Liset

    2013-01-01

    Honey storage initiates melanoidin formation that involves a cascade of seemingly unguided redox reactions between amino acids/proteins, reducing sugars and polyphenols. In the process, high molecular weight protein-polyphenol complexes are formed, but the mechanism involved remains unknown. The objective of this study was twofold: to determine quantitative and qualitative changes in proteins in honeys stored for prolonged times and in different temperatures and to relate these changes to the formation of protein-polyphenol complexes. Six -month storage decreased the protein content by 46.7% in all tested honeys (t-test, p<0.002) with the rapid reduction occurring during the first three month. The changes in protein levels coincided with alterations in molecular size and net charge of proteins on SDS –PAGE. Electro-blotted proteins reacted with a quinone-specific nitro blue tetrazolium (NBT) on nitrocellulose membranes indicating that quinones derived from oxidized polyphenols formed covalent bonds with proteins. Protein-polyphenol complexes isolated by size-exclusion chromatography differed in size and stoichiometry and fall into two categories: (a) high molecular weight complexes (230–180 kDa) enriched in proteins but possessing a limited reducing activity toward the NBT and (b) lower molecular size complexes (110–85 kDa) enriched in polyphenols but strongly reducing the dye. The variable stoichiometry suggest that the large, “protein-type” complexes were formed by protein cross-linking, while in the smaller, “polyphenol-type” complexes polyphenols were first polymerized prior to protein binding. Quinones preferentially bound a 31 kDa protein which, by the electrospray quadrupole time of flight mass spectrometry (ESI-Qtof-MS) analysis, showed homology to dirigent-like proteins known for assisting in radical coupling and polymerization of phenolic compounds. These findings provide a new look on protein-polyphenol interaction in honey where the

  7. Myelin basic protein is a glial microtubule-associated protein -- characterization of binding domains, kinetics of polymerization, and regulation by phosphorylation and a lipidic environment.

    PubMed

    Zienowicz, Agata; Bamm, Vladimir V; Vassall, Kenrick A; Harauz, George

    2015-05-22

    The 18.5-kDa splice isoform of myelin basic protein (MBP) predominates in the adult brain, adhering the cytoplasmic leaflets of the oligodendrocyte membrane together, but also assembling the cytoskeleton at leading edges of membrane processes. Here, we characterized MBP's role as a microtubule-assembly protein (MAP). Using light scattering and sedimentation assays we found that pseudo-phosphorylation of Ser54 (murine 18.5-kDa sequence) significantly enhanced the rate but not the final degree of polymerization. This residue lies within a short KPGSG motif identical to one in tau, a ubiquitous MAP important in neuronal microtubule assembly. Using polypeptide constructs, each comprising one of three major amphipathic α-helical molecular recognition fragments of 18.5-kDa MBP, we identified the N-terminal α1-peptide as sufficient to cause microtubule polymerization, the rate of which was significantly enhanced in the presence of dodecylphosphocholine (DPC) micelles to mimic a lipidic environment. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. The aqueous phase of Alzheimer's disease brain contains assemblies built from ∼4 and ∼7 kDa Aβ species.

    PubMed

    Mc Donald, Jessica M; O'Malley, Tiernan T; Liu, Wen; Mably, Alexandra J; Brinkmalm, Gunnar; Portelius, Erik; Wittbold, William M; Frosch, Matthew P; Walsh, Dominic M

    2015-11-01

    Much knowledge about amyloid β (Aβ) aggregation and toxicity has been acquired using synthetic peptides and mouse models, whereas less is known about soluble Aβ in human brain. We analyzed aqueous extracts from multiple AD brains using an array of techniques. Brains can contain at least four different Aβ assembly forms including: (i) monomers, (ii) a ∼7 kDa Aβ species, and larger species (iii) from ∼30-150 kDa, and (iv) >160 kDa. High molecular weight species are by far the most prevalent and appear to be built from ∼7 kDa Aβ species. The ∼7 kDa Aβ species resist denaturation by chaotropic agents and have a higher Aβ42/Aβ40 ratio than monomers, and are unreactive with antibodies to Asp1 of Ab or APP residues N-terminal of Asp1. Further analysis of brain-derived ∼7 kDa Aβ species, the mechanism by which they assemble and the structures they form should reveal therapeutic and diagnostic opportunities. Copyright © 2015 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

  9. Cloning and expression of the translocator protein (18 kDa), voltage-dependent anion channel, and diazepam binding inhibitor in the gonad of largemouth bass (Micropterus salmoides) across the reproductive cycle.

    PubMed

    Doperalski, Nicholas J; Martyniuk, Christopher J; Prucha, Melinda S; Kroll, Kevin J; Denslow, Nancy D; Barber, David S

    2011-08-01

    Cholesterol transport across the mitochondrial membrane is rate-limiting for steroidogenesis in vertebrates. Previous studies in fish have characterized expression of the steroidogenic acute regulatory protein, however the function and regulation of other genes and proteins involved in piscine cholesterol transport have not been evaluated. In the current study, mRNA sequences of the 18 kDa translocator protein (tspo; formerly peripheral benzodiazepine receptor), voltage-dependent anion channel (vdac), and diazepam binding inhibitor (dbi; also acyl-CoA binding protein) were cloned from largemouth bass. Gonadal expression was examined across reproductive stages to determine if expression is correlated with changes in steroid levels and with indicators of reproductive maturation. In testis, transcript abundance of tspo and dbi increased with reproductive maturation (6- and 23-fold maximal increase, respectively) and expression of tspo and dbi was positively correlated with reproductive stage, gonadosomatic index (GSI), and circulating levels of testosterone. Testis vdac expression was positively correlated with reproductive stage and GSI. In females, gonadal tspo and vdac expression was negatively correlated with GSI and levels of plasma testosterone and 17β-estradiol. Ovarian dbi expression was not correlated with indicators of reproductive maturation. These studies represent the first investigation of the steroidogenic role of tspo, vdac, and dbi in fish. Findings suggest that cholesterol transport in largemouth bass testis, but not in ovary, may be transcriptionally-regulated, however further investigation will be necessary to fully elucidate the role of these genes in largemouth bass steroidogenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

  10. Localization and dynamic expression of a 27.8 kDa receptor protein for lymphocystis disease virus infection in sea bass ( Lateolabrax japonicus) tissues

    NASA Astrophysics Data System (ADS)

    Wu, Ronghua; Sheng, Xiuzhen; Tang, Xiaoqian; Xing, Jing; Zhan, Wenbin

    2017-10-01

    Lymphocystis disease virus (LCDV) infects target cells by attaching to a 27.8 kDa receptor (27.8R) protein in flounder Paralichthys olivaceus, and anti-27.8R monoclonal antibodies (MAbs) have been developed. However, the 27.8R existence in tissues of sea bass ( Lateolabrax japonicus) and its role in LCDV infection have remained unclear. In this study, the results of western blotting demonstrated that the same 27.8R was shared by flounder and sea bass. LCDV-free sea bass individuals were intramuscularly injected with LCDV, and viral copies were detected in tissues from 3 h post infection and showed a time-dependent increase during 9 days infection. Distribution and synthesis of 27.8R in sea bass tissues were investigated by using anti-27.8R MAbs as probes. It was found that 27.8R was distributed in all the tested tissues. The levels of 27.8R protein were highest in gill and skin, then a bit lowly in stomach, head kidney and heart, followed by spleen, intestine, blood cells, gonad and liver, and least in kidney and brain in healthy sea bass. Upon LCDV infection, 27.8R synthesis was up-regulated in each tissue, and higher in the tissues with higher LCDV copies. The 27.8R and LCDV were detected in some peripheral blood leukocytes but not in red blood cells. These results suggested that 27.8R was widely distributed in sea bass tissues, and it served as a receptor and correlated with tissue tropism of LCDV infection. Furthermore, leukocytes had the potential of being a LCDV carrier and were responsible for a systemic infection of LCDV in sea bass.

  11. Attenuated migration by green tea extract (-)-epigallocatechin gallate (EGCG): involvement of 67 kDa laminin receptor internalization in macrophagic cells.

    PubMed

    Ren, Xuezhi; Guo, Xingzhi; Chen, Li; Guo, Minxia; Peng, Ning; Li, Rui

    2014-08-01

    Excessive activation of the microglia in the brain is involved in the development of several neurodegenerative diseases. Previous studies have indicated that (-)-epigallocatechin gallate (EGCG), a major active constituent of green tea, exhibits potent suppressive effects on the activation of microglia. As the 67 kDa laminin receptor (67LR) is a key element in cellular activation and migration, we investigated the effect of EGCG on cell migration and 67LR in lipopolysaccharide (LPS)-activated macrophagic RAW264.7 cells. The presence of EGCG (1-25 μM) markedly attenuated LPS-induced cell migration in a dose-dependent manner. However, the total amount of 67LR protein in the RAW264.7 cells was unaffected by EGCG, as revealed by Western blot analysis. In addition, confocal immunofluorescence microscopy indicated that EGCG caused a marked membrane translocation of 67LR from the membrane surface towards the cytoplasm. Cell-surface biotinylation analysis confirmed that EGCG induced a significant internalization of 67LR by 24-68% in a dose-dependent manner. This study helps to explain the pharmacological action of EGCG on 67LR, suggesting its potential use in the treatment of diseases associated with macrophage/microglia activation, such as neurodegenerative diseases and cancer.

  12. VBNC Legionella pneumophila cells are still able to produce virulence proteins.

    PubMed

    Alleron, Laëtitia; Khemiri, Arbia; Koubar, Mohamad; Lacombe, Christian; Coquet, Laurent; Cosette, Pascal; Jouenne, Thierry; Frere, Jacques

    2013-11-01

    Legionella pneumophila is the agent responsible for legionellosis. Numerous bacteria, including L. pneumophila, can enter into a viable but not culturable (VBNC) state under unfavorable environmental conditions. In this state, cells are unable to form colonies on standard medium but are still alive. Here we show that VBNC L. pneumophila cells, obtained by monochloramine treatment, were still able to synthesize proteins, some of which are involved in virulence. Protein synthesis was measured using (35)S-labeling and the proteomes of VBNC and culturable cells then compared. This analysis allowed the identification of nine proteins that were accumulated in the VBNC state. Among them, four were involved in virulence, i.e., the macrophage infectivity potentiator protein, the hypothetical protein lpl2247, the ClpP protease proteolytic subunit and the 27 kDa outer membrane protein. Others, i.e., the enoyl reductase, the electron transfer flavoprotein (alpha and beta subunits), the 50S ribosomal proteins (L1 and L25) are involved in metabolic and energy production pathways. However, resuscitation experiments performed with Acanthamoeba castellanii failed, suggesting that the accumulation of virulence factors by VBNC cells is not sufficient to maintain their virulence. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Protective ability against oxidative stress of brewers' spent grain protein hydrolysates.

    PubMed

    Vieira, Elsa F; da Silva, Diana Dias; Carmo, Helena; Ferreira, Isabel M P L V O

    2017-08-01

    The protein fraction of Brewers' spent grain (BSG) was used as substrate to obtain hydrolysates with antioxidant activity. Three enzymatic approaches were applied: brewer's spent yeast (BSY) proteases, Neutrase® and Alcalase®, at the same proteolytic activity (1U/mL), using an enzyme/substrate ratio of 10:100 (v/v), at 50°C, 4h. Total Phenolic Content (TPC) and Ferric Ion Reducing Antioxidant Power (FRAP) of hydrolysates and fractions <10kDa and <3kDa were assayed. Additionally, the protective ability of <10kDa fractions against oxidative stress on Caco-2 and HepG2 cells was investigated. Alcalase® hydrolysate presented significantly (p<0.05) higher TPC and FRAP (0.083mgGAE/mgdw; 0.101mgTE/mgdw, respectively) than Neutrase® and BSY hydrolysates. The three BSG protein hydrolysates (fraction <10kDa) exerted protective effect against free-radical induced cytotoxicity in Caco-2 and HepG2 cell lines, but the strongest effect was observed for BSY hydrolysates, therefore, it presents greater potential as functional ingredient. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Identification of the heat shock protein 70 (HLHsp70) in Haemaphysalis longicornis.

    PubMed

    Tian, Zhancheng; Liu, Guangyuan; Zhang, Liyan; Yin, Hong; Wang, Hui; Xie, Junren; Zhang, Ping; Luo, Jin

    2011-09-27

    A Haemaphysalis longicornis heat shock protein 70 (HLHsp70) was identified from a cDNA library synthesized from tick eggs. The HLHsp70 cDNA is 2311 bp in length and encodes 661 amino acid residues with the predicted molecular weight of 72.5 kDa and an isoelectronic point (pI) of 5.2. It also contains the highly conserved functional motifs of the Hsp70 family and a specific endoplasmic reticulum (ER) retention signal "KDEL" that is common among ER-localized proteins. The HLHsp70 exhibits 90% amino acid identity to the putative Hsp70 of Ixodes scapularis, and 85% to Gallus gallus 78 kDa glucose-regulated protein precursor. Real time RT-PCR analysis showed that the expression levels of the Hsp70 in ovaries and salivary glands were significantly higher than in other tested tissues in partially fed females. Although the expression level of the HLHsp70 was constantly low in unfed ticks, it was significantly induced by blood-feeding. Further, the expression was positively correlated to the temperature (4-37°C, tested). Western blot analysis showed that the rabbit antiserum against the recombinant HLHsp70 protein (rHLHSP70) recognized bands of approximately 100, 72, and 28 kDa from egg lysates, as well as a 72kDa fragment in protein extracts from partially fed larvae. Immunization of rabbits with the rHLHSP70 did not result in a statistically significant reduction of female tick engorgement and oviposition. These results suggest that although HLHSP70 plays a role in the physiological activities of ticks, as a constitutive protein it was not suitable for selection as a candidate vaccine antigen against ticks. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Colocalization of insulin-like growth factor-binding protein with insulin-like growth factor I.

    PubMed

    Kobayashi, S; Clemmons, D R; Venkatachalam, M A

    1991-07-01

    We report the localization of insulin-like growth factor I (IGF-I) and a 25-kDa form of insulin-like growth factor-binding protein (IGF-BP-1) in adult rat kidney. The antigens were localized using a rabbit anti-human IGF-I antibody, and a rabbit anti-human IGF-BP-1 antibody raised against human 25-kDa IGF-BP-1 purified from amniotic fluid. Immunohistochemistry by the avidin-biotin peroxidase conjugate technique showed that both peptides are located in the same nephron segments, in the same cell types. The most intense staining was in papillary collecting ducts. There was moderate staining also in cortical collecting ducts and medullary thick ascending limbs of Henle's loop. In collecting ducts the antigens were shown to be present in principal cells but not in intercalated cells. In distal convoluted tubules, cortical thick ascending limbs, and in structures presumptively identified as thin limbs of Henle's loops there was only modest staining. The macula densa, however, lacked immunoreactivity. Colocalization of IGF-I and IGF-BP-1 in the same cells supports the notion, derived from studies on cultured cells, that the actions of IGF-I may be modified by IGF-BPs that are present in the same location.

  16. StAR Protein Stability in Y1 and Kin-8 Mouse Adrenocortical Cells.

    PubMed

    Clark, Barbara J; Hudson, Elizabeth A

    2015-03-04

    The steroidogenic acute regulatory protein (STAR) protein expression is required for cholesterol transport into mitochondria to initiate steroidogenesis in the adrenal and gonads. STAR is synthesized as a 37 kDa precursor protein which is targeted to the mitochondria and imported and processed to an intra-mitochondrial 30 kDa protein. Tropic hormone stimulation of the cAMP-dependent protein kinase A (PKA) signaling pathway is the major contributor to the transcriptional and post-transcriptional regulation of STAR synthesis. Many studies have focused on the mechanisms of cAMP-PKA mediated control of STAR synthesis while there are few reports on STAR degradation pathways. The objective of this study was to determine the effect of cAMP-PKA-dependent signaling on STAR protein stability. We have used the cAMP-PKA responsive Y1 mouse adrenocortical cells and the PKA-deficient Kin-8 cells to measure STAR phosphorylation and protein half-life. Western blot analysis and standard radiolabeled pulse-chase experiments were used to determine STAR phosphorylation status and protein half-life, respectively. Our data demonstrate that PKA-dependent STAR phosphorylation does not contribute to 30 kDa STAR protein stability in the mitochondria. We further show that inhibition of the 26S proteasome does not block precursor STAR phosphorylation or steroid production in Y1 cells. These data suggest STAR can maintain function and promote steroidogenesis under conditions of proteasome inhibition.

  17. StAR Protein Stability in Y1 and Kin-8 Mouse Adrenocortical Cells

    PubMed Central

    Clark, Barbara J.; Hudson, Elizabeth A.

    2015-01-01

    The steroidogenic acute regulatory protein (STAR) protein expression is required for cholesterol transport into mitochondria to initiate steroidogenesis in the adrenal and gonads. STAR is synthesized as a 37 kDa precursor protein which is targeted to the mitochondria and imported and processed to an intra-mitochondrial 30 kDa protein. Tropic hormone stimulation of the cAMP-dependent protein kinase A (PKA) signaling pathway is the major contributor to the transcriptional and post-transcriptional regulation of STAR synthesis. Many studies have focused on the mechanisms of cAMP-PKA mediated control of STAR synthesis while there are few reports on STAR degradation pathways. The objective of this study was to determine the effect of cAMP-PKA-dependent signaling on STAR protein stability. We have used the cAMP-PKA responsive Y1 mouse adrenocortical cells and the PKA-deficient Kin-8 cells to measure STAR phosphorylation and protein half-life. Western blot analysis and standard radiolabeled pulse-chase experiments were used to determine STAR phosphorylation status and protein half-life, respectively. Our data demonstrate that PKA-dependent STAR phosphorylation does not contribute to 30 kDa STAR protein stability in the mitochondria. We further show that inhibition of the 26S proteasome does not block precursor STAR phosphorylation or steroid production in Y1 cells. These data suggest STAR can maintain function and promote steroidogenesis under conditions of proteasome inhibition. PMID:25749137

  18. Transcriptional induction of the heat shock protein B8 mediates the clearance of misfolded proteins responsible for motor neuron diseases.

    PubMed

    Crippa, Valeria; D'Agostino, Vito G; Cristofani, Riccardo; Rusmini, Paola; Cicardi, Maria E; Messi, Elio; Loffredo, Rosa; Pancher, Michael; Piccolella, Margherita; Galbiati, Mariarita; Meroni, Marco; Cereda, Cristina; Carra, Serena; Provenzani, Alessandro; Poletti, Angelo

    2016-03-10

    Neurodegenerative diseases (NDs) are often associated with the presence of misfolded protein inclusions. The chaperone HSPB8 is upregulated in mice, the human brain and muscle structures affected during NDs progression. HSPB8 exerts a potent pro-degradative activity on several misfolded proteins responsible for familial NDs forms. Here, we demonstrated that HSPB8 also counteracts accumulation of aberrantly localized misfolded forms of TDP-43 and its 25KDa fragment involved in most sporadic cases of Amyotrophic Lateral Sclerosis (sALS) and of Fronto Lateral Temporal Dementia (FLTD). HSPB8 acts with BAG3 and the HSP70/HSC70-CHIP complex enhancing the autophagic removal of misfolded proteins. We performed a high-through put screening (HTS) to find small molecules capable of inducing HSPB8 in neurons for therapeutic purposes. We identified two compounds, colchicine and doxorubicin, that robustly up-regulated HSPB8 expression. Both colchicine and doxorubicin increased the expression of the master regulator of autophagy TFEB, the autophagy linker p62/SQSTM1 and the autophagosome component LC3. In line, both drugs counteracted the accumulation of TDP-43 and TDP-25 misfolded species responsible for motoneuronal death in sALS. Thus, analogs of colchicine and doxorubicin able to induce HSPB8 and with better safety and tolerability may result beneficial in NDs models.

  19. Synaptosomal-associated protein 25 (Snap-25) gene polymorphism frequency in fibromyalgia syndrome and relationship with clinical symptoms.

    PubMed

    Balkarli, Ayse; Sengül, Cem; Tepeli, Emre; Balkarli, Huseyin; Cobankara, Veli

    2014-05-31

    SNAP-25 protein is contributory to plasma membrane and synaptic vesicle fusions that are critical points in neurotransmission. SNAP-25 gene is associated with behavioral symptoms, personality and psychological disorders. In addition, SNAP-25 protein can be related to different neurotransmitter functions due to its association with vesicle membrane transition and fusion. This is important because neurologic, cognitive, and psychologic disorders in fibromyalgia syndrome (FMS) can be related to this function. This relationship may be enlightening for etiopathogenesis of FMS and treatment approaches. We aimed to study a SNAP-25 gene polymorphism, which is related to many psychiatric diseases, and FMS association in this prospective study. We included 71 patients who were diagnosed according to new criteria and 57 matched healthy women in this study. Both groups were evaluated regarding age, height, weight, BMI, education level, marital and occupational status. A new diagnosis of FMS was made from criteria scoring, SF-36, Beck depression scale, and VAS that were applied to the patient group. SNAP-25 gene polymorphism and disease activity score correlations were compared. Mean age was 38±5,196 and 38.12±4.939 in patient and control groups, respectively (p=0.542). No significant difference was found between groups regarding age, height, weight, BMI, education level, marital or occupational status (p > 0.05). Ddel T/C genotype was significantly higher in the patient group (p = 0.009). MnlI gene polymorphism did not show a correlation with any score whereas a significant correlation was found between Ddel T/C genotype and Beck depression scale and VAS score (p < 0.05). FMS etiopathogenesis is not clearly known. Numerous neurologic, cognitive and psychological disorders were found during studies looking at cause. Our study showed increased SNAP-25 Ddel T/C genotype in FMS patients compared to the control group, which is related to behavioral symptoms, personality and

  20. Hepatitis B virus enhances cisplatin-induced hepatotoxicity via a mechanism involving suppression of glucose-regulated protein of 78 Kda.

    PubMed

    Zhang, Xiaoxue; Zhang, Rui; Yang, HuiOu; Xiang, Qian; Jiang, Qing; He, Qi; Zhang, Ting; Chen, Chen; Zhu, Huifen; Wang, Qiang; Ning, Qin; Li, Yiwu; Lei, Ping; Shen, Guanxin

    2016-07-25

    Cisplatin is a classical platinum-based chemotherapeutic drug used in the treatment of many cancer types, including hepatocellular carcinoma (HCC). The application of cisplatin is significantly limited by its toxicity, which may be affected by various biological factors. Persistence of Hepatitis B virus (HBV) infection leads to HCC development and may be associated with higher incidence of severe hepatitis during chemotherapy. However, whether HBV alters the susceptibility of hepatocytes to cisplatin remains poorly understood. Here, we demonstrate that HBV transfection enhanced cisplatin-induced hepatotoxicity via a mechanism involving suppression of glucose-regulated protein of 78 KDa (Grp78), a major stress-induced chaperone that localizes to the endoplasmic reticulum. Silencing Grp78 gene increased the susceptibility of HepG2 to cisplatin by activating caspase-3. Grp78 expression was down-regulated by HBV infection both in vitro and in liver tissues of patients. We compared the cisplatin sensitivity of hepatoma cells either expressing (HepG2.2.15 cells) or not expressing the entire Hepatitis B Virus genome (HepG2). HepG2.2.15 cells showed increased sensitivity to cisplatin and a higher apoptosis rate. Overexpression of Grp78 counteracted the increase of sensitivity of HepG2.215 cells to cisplatin. Furthermore, we found that HBV disrupted Grp78 synthesis in response to cisplatin stimulation, which may trigger severe and prolonged endoplasmic reticulum (ER) stress that can induce cellular apoptosis. Our findings provide new information into the effect of HBV in the modulation of Grp78 expression, and, consequently on cisplatin-induced hepatotoxicity during viral infection. Copyright © 2016. Published by Elsevier Ireland Ltd.

  1. Experimental Protein Structure Verification by Scoring with a Single, Unassigned NMR Spectrum.

    PubMed

    Courtney, Joseph M; Ye, Qing; Nesbitt, Anna E; Tang, Ming; Tuttle, Marcus D; Watt, Eric D; Nuzzio, Kristin M; Sperling, Lindsay J; Comellas, Gemma; Peterson, Joseph R; Morrissey, James H; Rienstra, Chad M

    2015-10-06

    Standard methods for de novo protein structure determination by nuclear magnetic resonance (NMR) require time-consuming data collection and interpretation efforts. Here we present a qualitatively distinct and novel approach, called Comparative, Objective Measurement of Protein Architectures by Scoring Shifts (COMPASS), which identifies the best structures from a set of structural models by numerical comparison with a single, unassigned 2D (13)C-(13)C NMR spectrum containing backbone and side-chain aliphatic signals. COMPASS does not require resonance assignments. It is particularly well suited for interpretation of magic-angle spinning solid-state NMR spectra, but also applicable to solution NMR spectra. We demonstrate COMPASS with experimental data from four proteins--GB1, ubiquitin, DsbA, and the extracellular domain of human tissue factor--and with reconstructed spectra from 11 additional proteins. For all these proteins, with molecular mass up to 25 kDa, COMPASS distinguished the correct fold, most often within 1.5 Å root-mean-square deviation of the reference structure. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Inducible immune proteins in the dampwood termite Zootermopsis angusticollis

    NASA Astrophysics Data System (ADS)

    Rosengaus, Rebeca B.; Cornelisse, Tara; Guschanski, Katerina; Traniello, James F. A.

    2007-01-01

    Dampwood termites, Zootermopsis angusticollis (Isoptera: Termopsidae), mount an immune response to resist microbial infection. Here we report on results of a novel analysis that allowed us to electrophoretically assess changes in hemolymph proteins in the same individual before and after exposure to a pathogen. We demonstrate that contact with a sublethal concentration of the entomopathogenic fungus Metarhizium anisopliae (Deuteromycotina:Hypomycetes) induces the production of protective proteins in nymphs, pseudergates (false workers), and soldiers. Termites exposed to an immunizing dosage of fungal conidia consistently showed an enhancement of constitutive proteins (62-85 kDa) in the hemolymph as well as an induction of novel proteins (28-48 kDa) relative to preimmunization levels. No significant differences in protein banding patterns relative to baseline levels in control and naïve termites were observed. Incubating excised and eluted induced proteins produced by immunized pseudergates or immunized soldiers with conidia significantly reduced the germination of the fungus. The fungistatic effect of eluted proteins differed significantly among five colonies examined. Our results show that the upregulation of protective proteins in the hemolymph underscores the in vivo immune response we previously recorded in Z. angusticollis.

  3. Intracellular and extracellular expression of the major inducible 70kDa heat shock protein in experimental ischemia-reperfusion injury of the spinal cord.

    PubMed

    Awad, Hamdy; Suntres, Zacharias; Heijmans, John; Smeak, Daniel; Bergdall-Costell, Valerie; Christofi, Fievos L; Magro, Cynthia; Oglesbee, Michael

    2008-08-01

    Inflammatory responses exacerbate ischemia-reperfusion (IR) injury of spinal cord, although understanding of mediators is incomplete. The major inducible 70kDa heat shock protein (hsp70) is induced by ischemia and extracellular hsp70 (e-hsp70) can modulate inflammatory responses, but there is no published information regarding e-hsp70 levels in the cerebrospinal fluid (CSF) or serum as part of any neurological disease state save trauma. The present work addresses this deficiency by examining e-hsp70 in serum and CSF of dogs in an experimental model of spinal cord IR injury. IR injury of spinal cord caused hind limb paraplegia within 2-3 h that was correlated to lumbosacral poliomalacia with T cell infiltrates at 3 d post-ischemia. In this context, we showed a 5.2-fold elevation of e-hsp70 in CSF that was induced by ischemia and was sustained for the following 3 d observation interval. Plasma e-hsp70 levels were unaffected by IR injury, indicating e-hsp70 release from within the central nervous system. A putative source of this e-hsp70 was ependymal cells in the ischemic penumbra, based upon elevated i-hsp70 levels detected within these cells. Results warrant further investigation of e-hsp70's potential to modulate spinal cord IR injury.

  4. Completely monodisperse, highly repetitive proteins for bioconjugate capillary electrophoresis: Development and characterization

    PubMed Central

    Lin, Jennifer S.; Albrecht, Jennifer Coyne; Meagher, Robert J.; Wang, Xiaoxiao; Barron, Annelise E.

    2011-01-01

    Protein-based polymers are increasingly being used in biomaterial applications due to their ease of customization and potential monodispersity. These advantages make protein polymers excellent candidates for bioanalytical applications. Here we describe improved methods for producing drag-tags for Free-Solution Conjugate Electrophoresis (FSCE). FSCE utilizes a pure, monodisperse recombinant protein, tethered end-on to a ssDNA molecule, to enable DNA size separation in aqueous buffer. FSCE also provides a highly sensitive method to evaluate the polydispersity of a protein drag-tag and thus its suitability for bioanalytical uses. This method is able to detect slight differences in drag-tag charge or mass. We have devised an improved cloning, expression, and purification strategy that enables us to generate, for the first time, a truly monodisperse 20 kDa protein polymer and a nearly monodisperse 38 kDa protein. These newly produced proteins can be used as drag-tags to enable longer read DNA sequencing by free-solution microchannel electrophoresis. PMID:21553840

  5. Purification and characterization of protein phosphatase 2A from petals of the tulip Tulipa gesnerina.

    PubMed

    Azad, Md Abul Kalam; Sawa, Yoshihiro; Ishikawa, Takahiro; Shibata, Hitoshi

    2006-11-30

    The holoenzyme of protein phosphatase (PP) from tulip petals was purified by using hydrophobic interaction, anion exchange and microcystin affinity chromatography to analyze activity towards p-nitrophenyl phosphate (p-NPP). The catalytic subunit of PP was released from its endogenous regulatory subunits by ethanol precipitation and further purified. Both preparations were characterized by immunological and biochemical approaches to be PP2A. On SDS-PAGE, the final purified holoenzyme preparation showed three protein bands estimated at 38, 65, and 75 kDa while the free catalytic subunit preparation showed only the 38 kDa protein. In both preparations, the 38 kDa protein was identified immunologically as the catalytic subunit of PP2A by using a monoclonal antibody against the PP2A catalytic subunit. The final 623- and 748- fold purified holoenzyme and the free catalytic preparations, respectively, exhibited high sensitivity to inhibition by 1 nM okadaic acid when activity was measured with p-NPP. The holoenzyme displayed higher stimulation in the presence of ammonium sulfate than the free catalytic subunit did by protamine, thereby suggesting different enzymatic behaviors.

  6. Packaging of the virion host shutoff (Vhs) protein of herpes simplex virus: two forms of the Vhs polypeptide are associated with intranuclear B and C capsids, but only one is associated with enveloped virions.

    PubMed

    Read, G Sullivan; Patterson, Mary

    2007-02-01

    The virion host shutoff (Vhs) protein (UL41) is a minor component of herpes simplex virus virions which, following penetration, accelerates turnover of host and viral mRNAs. Infected cells contain 58-kDa and 59.5-kDa forms of Vhs, which differ in the extent of phosphorylation, yet only a 58-kDa polypeptide is incorporated into virions. In pulse-chase experiments, the primary Vhs translation product comigrated in sodium dodecyl sulfate-polyacrylamide gel electrophoresis with the 58-kDa virion polypeptide, and could be chased to 59.5 kDa. While both 59.5-kDa and 58-kDa forms were found in nuclear and cytoplasmic fractions, the 59.5-kDa form was significantly enriched in the nucleus. Both forms were associated with intranuclear B and C capsids, yet only the 58-kDa polypeptide was found in enveloped cytoplasmic virions. A 58-kDa form, but not the 59.5-kDa form, was found in L particles, noninfectious particles that contain an envelope and tegument but no capsid. The data suggest that virions contain two populations of Vhs that are packaged by different pathways. In the first pathway, the primary translation product is processed to 59.5 kDa, is transported to the nucleus, binds intranuclear capsids, and is converted to 58 kDa at some stage prior to final envelopment. The second pathway does not involve the 59.5-kDa form or interactions between Vhs and capsids. Instead, the primary translation product is phosphorylated to the 58-kDa virion form and packaged through interactions with other tegument proteins in the cytoplasm or viral envelope proteins at the site of final envelopment.

  7. 2'-5'-Oligoadenylate Synthetase-Like Protein Inhibits Respiratory Syncytial Virus Replication and Is Targeted by the Viral Nonstructural Protein 1.

    PubMed

    Dhar, Jayeeta; Cuevas, Rolando A; Goswami, Ramansu; Zhu, Jianzhong; Sarkar, Saumendra N; Barik, Sailen

    2015-10-01

    2'-5'-Oligoadenylate synthetase-like protein (OASL) is an interferon-inducible antiviral protein. Here we describe differential inhibitory activities of human OASL and the two mouse OASL homologs against respiratory syncytial virus (RSV) replication. Interestingly, nonstructural protein 1 (NS1) of RSV promoted proteasome-dependent degradation of specific OASL isoforms. We conclude that OASL acts as a cellular antiviral protein and that RSV NS1 suppresses this function to evade cellular innate immunity and allow virus growth. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  8. A DNA fragment of Leptospira interrogans encodes a protein which shares epitopes with equine cornea.

    PubMed

    Lucchesi, P M; Parma, A E

    1999-11-30

    Horses infected with Leptospira interrogans present several clinical disorders, one of them being recurrent uveitis. An antigenic relationship between this bacterium and equine cornea has been described in previous studies. With the aim to make progress on defining the molecular basis and pathogenesis of equine recurrent uveitis, here we describe the cloning of one DNA fragment from a Leptospira interrogans serovar pomona genomic lambda gt11 library. Although there are references of transcription of leptospiral genes in E. coli from their own leptospiral promoters, in this recombinant construction the leptospiral DNA was located under the control of lacZ promoter since no expression could be detected in the absence of IPTG. This clone, isolated by expression screening with polyclonal serum raised against equine corneal proteins, encodes a 90 kDa protein of L. interrogans which crossreacts with equine cornea as proved Western-blotting. Antibodies directed against this leptospiral protein strongly recognised a 66 kDa equine corneal protein, one of those recognised by an anti-equine cornea serum. Our findings suggest that an immune response to 90 kDa protein participates in pathogenesis of equine uveitis.

  9. The N-terminal Set-β Protein Isoform Induces Neuronal Death*

    PubMed Central

    Trakhtenberg, Ephraim F.; Morkin, Melina I.; Patel, Karan H.; Fernandez, Stephanie G.; Sang, Alan; Shaw, Peter; Liu, Xiongfei; Wang, Yan; Mlacker, Gregory M.; Gao, Han; Velmeshev, Dmitry; Dombrowski, Susan M.; Vitek, Michael P.; Goldberg, Jeffrey L.

    2015-01-01

    Set-β protein plays different roles in neurons, but the diversity of Set-β neuronal isoforms and their functions have not been characterized. The expression and subcellular localization of Set-β are altered in Alzheimer disease, cleavage of Set-β leads to neuronal death after stroke, and the full-length Set-β regulates retinal ganglion cell (RGC) and hippocampal neuron axon growth and regeneration in a subcellular localization-dependent manner. Here we used various biochemical approaches to investigate Set-β isoforms and their role in the CNS, using the same type of neurons, RGCs, across studies. We found multiple alternatively spliced isoforms expressed from the Set locus in purified RGCs. Set transcripts containing the Set-β-specific exon were the most highly expressed isoforms. We also identified a novel, alternatively spliced Set-β transcript lacking the nuclear localization signal and demonstrated that the full-length (∼39-kDa) Set-β is localized predominantly in the nucleus, whereas a shorter (∼25-kDa) Set-β isoform is localized predominantly in the cytoplasm. Finally, we show that an N-terminal Set-β cleavage product can induce neuronal death. PMID:25833944

  10. Top-Down Protein Identification of Proteasome Proteins with nanoLC FT-ICR MS Employing Data-Independent Fragmentation Methods

    PubMed Central

    Lakshmanan, Rajeswari; Wolff, Jeremy J.; Alvarado, Rudy; Loo, Joseph A.

    2014-01-01

    A comparison of different data-independent fragmentation methods combined with liquid chromatography (LC) coupled to high resolution Fourier-transform ion cyclotron resonance (FT-ICR) tandem mass spectrometry (MS) is presented for top-down MS of protein mixtures. Proteins composing the 20S and 19S proteasome complex and their post-translational modifications were identified using a 15-Tesla FT-ICR mass spectrometer. The data-independent fragmentation modes with LC timescales allowed for higher duty cycle measurements that better suit on-line LC-FT-ICR-MS. Protein top-down dissociation was effected by funnel-skimmer collisionally activated dissociation (FS-CAD) and CASI (Continuous Accumulation of Selected Ions)-CAD. The N-terminus for 9 out of the 14 20S proteasome proteins were found to be modified, and the α3 protein was found to be phosphorylated; these results are consistent with previous reports. Mass measurement accuracy with the LC-FT-ICR system for the 20–30 kDa 20S proteasome proteins was 1 ppm. The intact mass of the 100 kDa Rpn1 subunit from the 19S proteasome complex regulatory particle was measured with a deviation of 17 ppm. The CASI-CAD technique is a complementary tool for intact protein fragmentation and is an effective addition to the growing inventory of dissociation methods which are compatible with on-line protein separation coupled to FT-ICR MS. PMID:24478249

  11. Purification, identification and preliminary crystallographic studies of a 2S albumin seed protein from Lens culinaris

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gupta, Pankaj; Gaur, Vineet; Salunke, Dinakar M., E-mail: dinakar@nii.res.in

    2008-08-01

    A 2S albumin from L. culinaris was purified and crystallized and preliminary crystallographic studies were carried out. Lens culinaris (lentil) is a widely consumed high-protein-content leguminous crop. A 2S albumin protein (26.5 kDa) has been identified using NH{sub 2}-terminal sequencing from a 90% ammonium sulfate saturation fraction of total L. culinaris seed protein extract. The NH{sub 2}-terminal sequence shows very high homology to PA2, an allergy-related protein from Pisum sativum. The 2S albumin protein was purified using a combination of size-exclusion and ion-exchange chromatography. Crystals of the 2S seed albumin obtained using the hanging-drop vapour-diffusion method diffracted to 2.5 Åmore » resolution and were indexed in space group P4{sub 1} (or P4{sub 3}), with unit-cell parameters a = b = 78.6, c = 135.2 Å.« less

  12. Biological effects of individually synthesized TNF-binding domain of variola virus CrmB protein.

    PubMed

    Tsyrendorzhiev, D D; Orlovskaya, I A; Sennikov, S V; Tregubchak, T V; Gileva, I P; Tsyrendorzhieva, M D; Shchelkunov, S N

    2014-06-01

    The biological characteristics of a 17-kDa protein synthesized in bacterial cells, a TNF-binding domain (VARV-TNF-BP) of a 47-kDa variola virus CrmB protein (VARV-CrmB) consisting of TNF-binding and chemokine-binding domains, were studied. Removal of the C-terminal chemokine-binding domain from VARV-CrmB protein was inessential for the efficiency of its inhibition of TNF cytotoxicity towards L929 mouse fibroblast culture and for TNF-induced oxidative metabolic activity of mouse blood leukocytes. The results of this study could form the basis for further studies of VARV-TNF-BP mechanisms of activity for prospective use in practical medicine.

  13. A novel cold-regulated gene, COR25, of Brassica napus is involved in plant response and tolerance to cold stress.

    PubMed

    Chen, Liang; Zhong, Hui; Ren, Feng; Guo, Qian-Qian; Hu, Xu-Peng; Li, Xue-Bao

    2011-04-01

    Cold stress, which causes dehydration damage to the plant cell, is one of the most common abiotic stresses that adversely affect plant growth and crop productivity. To improve its cold-tolerance, plants often enhance expression of some cold-related genes. In this study, a cold-regulated gene encoding 25 KDa of protein was isolated from Brassica napus cDNA library using a macroarray analysis, and is consequently designated as BnCOR25. RT-PCR analysis demonstrated that BnCOR25 was expressed at high levels in hypocotyls, cotyledons, stems, and flowers, but its mRNA was found at low levels in roots and leaves. Northern blot analysis revealed that BnCOR25 transcripts were significantly induced by cold and osmotic stress treatment. The data also showed that BnCOR25 gene expression is mediated by ABA-dependent pathway. Overexpression of BnCOR25 in yeast (Schizosaccharomyces pombe) significantly enhanced the cell survival probability under cold stress, and overexpression of BnCOR25 in Arabidopsis enhances plant tolerance to cold stress. These results suggested that the BnCOR25 gene may play an important role in conferring freezing/cold tolerance in plants.

  14. Intracellular and transdermal protein delivery mediated by non-covalent interactions with a synthetic guanidine-rich molecular carrier.

    PubMed

    Im, Jungkyun; Das, Sanket; Jeong, Dongjun; Kim, Chang-Jin; Lim, Hyun-Suk; Kim, Ki Hean; Chung, Sung-Kee

    2017-08-07

    The impermeability of the cell plasma membrane is one of the major barriers for protein transduction into mammalian cells, and it also limits the use of proteins as therapeutic agents. Protein transduction has usually been achieved based on certain invasive processes or cell penetrating peptides (CPP). Herein we report our study in which a synthetic guanidine-rich molecular carrier is used as a delivery vector for intracellular and transdermal delivery of proteins. First a sorbitol-based molecular carrier having 8 guanidine units (Sor-G8) was synthesized, and then was simply mixed with a cargo protein of varying sizes to form the non-covalent complex of carrier-cargo proteins. These ionic complexes were shown to have efficient cellular uptake properties. The optimum conditions including the molar ratio between cargo protein and carrier, and the treatment time have been defined. Several protein cargoes were successfully examined with differing sizes and molecular weights: green fluorescent protein (MW 27kDa), albumin (66kDa), concanavalin A (102kDa), and immunoglobulin G (150kDa). These non-covalent complexes were also found to have excellent transdermal penetration ability into the mouse skin. The skin penetration depth was studied histologically by light microscopy as well as two-photon microscopy thus generating a depth profile. These complexes were largely found in the epidermis and dermis layers, i.e. down to ca. 100μm depth of the mouse skin. Our synthetic Sor-G8 carrier was found to be substantially more efficient that Arg8 in both the intracellular transduction and the transdermal delivery of proteins. The mechanism of the cellular uptake of the complex was briefly studied, and the results suggested macropinocytosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. A comparative study of the extracellular glucosyl- and fructosyltransferases from cariogenic and non-cariogenic Streptococcus mutans strains of two different serotypes.

    PubMed

    Asem, K; Cornish-Bowden, A J; Cole, J A

    1986-01-01

    Extracellular proteins from continuous cultures of serotype c and g Streptococcus mutans strains were separated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate. Gels stained with raffinose after electrophoresis revealed that although serotype c strains secrete two fructosyltransferases of molecular mass 68 kDa and 79 kDa, no fructosyltransferase was secreted by the serotype g strain K1. A sucrose activity stain was used to detect two glucosyltransferases (GTF) of molecular mass 162 kDa (bifunctional 1,6-alpha-D-glucan 3-alpha- and 6-alpha GTF or 'dextransucrase') and 153 kDa (a 1,3-alpha-D-glucan 3-alpha-GTF) in samples from cariogenic serotype c strains. Neither the 153 kDa protein nor the corresponding GTF activity was secreted by the non-cariogenic mutant C 67-25. The molecular masses of the corresponding 1,3-alpha and 1,6-alpha-GTF proteins from the serotype g strain K1 were 164 kDa and 158 kDa, respectively. All of the GTF proteins were degraded to discrete bands of lower molecular mass on storage at 4 degrees C even after extensive purification. The results provide an explanation for several outstanding controversies in the GTF literature.

  16. The hepta-beta-glucoside elicitor-binding proteins from legumes represent a putative receptor family.

    PubMed

    Mithöfer, A; Fliegmann, J; Neuhaus-Url, G; Schwarz, H; Ebel, J

    2000-08-01

    The ability of legumes to recognize and respond to beta-glucan elicitors by synthesizing phytoalexins is consistent with the existence of a membrane-bound beta-glucan-binding site. Related proteins of approximately 75 kDa and the corresponding mRNAs were detected in various species of legumes which respond to beta-glucans. The cDNAs for the beta-glucan-binding proteins of bean and soybean were cloned. The deduced 75-kDa proteins are predominantly hydrophilic and constitute a unique class of glucan-binding proteins with no currently recognizable functional domains. Heterologous expression of the soybean beta-glucan-binding protein in tomato cells resulted in the generation of a high-affinity binding site for the elicitor-active hepta-beta-glucoside conjugate (Kd = 4.5 nM). Ligand competition experiments with the recombinant binding sites demonstrated similar ligand specificities when compared with soybean. In both soybean and transgenic tomato, membrane-bound, active forms of the glucan-binding proteins coexist with immunologically detectable, soluble but inactive forms of the proteins. Reconstitution of a soluble protein fraction into lipid vesicles regained beta-glucoside-binding activity but with lower affinity (Kd = 130 nM). We conclude that the beta-glucan elicitor receptors of legumes are composed of the 75 kDa glucan-binding proteins as the critical components for ligand-recognition, and of an as yet unknown membrane anchor constituting the plasma membrane-associated receptor complex.

  17. Fractionation and antioxidant properties of rice bran protein hydrolysates stimulated by in vitro gastrointestinal digestion.

    PubMed

    Phongthai, Suphat; D'Amico, Stefano; Schoenlechner, Regine; Homthawornchoo, Wantida; Rawdkuen, Saroat

    2018-02-01

    Rice bran was used as a starting material to prepare protein concentrate through enzyme-assisted extraction. The hydrolysis of protein concentrate under in vitro gastrointestinal digestion (pepsin-trypsin system) greatly improved the antioxidant properties. Rice bran protein hydrolysate was further fractionated by membrane ultrafiltration (UF, F1: molecular weight (MW) <3kDa, F2: MW 3-5kDa, and F3: MW 5-10kDa). Peptides with smaller MW possessed higher antioxidant activities (P<0.05). UF showed a great efficacy to selectively separate the metal-chelating peptides. Tyrosine and phenylalanine had positive correlations with their DPPH & ABTS radicals scavenging activities and ferric reducing antioxidant power (r>0.831). A major peptide fragment was detected at m/z 1088 by a MALDI-TOF mass spectrometry. There is high potential that antioxidative peptides from rice bran might also be produced in the gastrointestinal tract of the human body. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Subinhibitory Concentrations of Antimicrobial Agents Reduce the Uptake of Legionella pneumophila into Acanthamoeba castellanii and U937 Cells by Altering the Expression of Virulence-Associated Antigens

    PubMed Central

    Lück, P. Christian; Schmitt, Jürgen W.; Hengerer, Arne; Helbig, Jürgen H.

    1998-01-01

    We determined the MICs of ampicillin, ciprofloxacin, erythromycin, imipenem, and rifampin for two clinical isolates of Legionella pneumophila serogroup 1 by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay and by quantitative culture. To test the influence of subinhibitory concentrations (sub-MICs) of antimicrobial agents on Legionella uptake into Acanthamoeba castellanii and U937 macrophage-like cells, both strains were pretreated with 0.25 MICs of the antibiotics for 24 h. In comparison to that for the untreated control, subinhibitory concentrations of antibiotics significantly reduced Legionella uptake into the host cells. Measurement of the binding of monoclonal antibodies against several Legionella antigens by enzyme-linked immunoassays indicated that sub-MIC antibiotic treatment reduced the expression of the macrophage infectivity potentiator protein (Mip), the Hsp 60 protein, the outer membrane protein (OmpM), an as-yet-uncharacterized protein of 55 kDa, and a few lipopolysaccharide (LPS) epitopes. In contrast, the expression of some LPS epitopes recognized by monoclonal antibodies 8/5 and 30/4 as well as a 45-kDa protein, a 58-kDa protein, and the major outer membrane protein (OmpS) remained unaffected. PMID:9797218

  19. Functional diversification and specialization of cytosolic 70-kDa heat shock proteins.

    PubMed

    McCallister, Chelsea; Siracusa, Matthew C; Shirazi, Farzaneh; Chalkia, Dimitra; Nikolaidis, Nikolas

    2015-03-20

    A fundamental question in molecular evolution is how protein functional differentiation alters the ability of cells and organisms to cope with stress and survive. To answer this question we used two paralogous Hsp70s from mouse and explored whether these highly similar cytosolic molecular chaperones, which apart their temporal expression have been considered functionally interchangeable, are differentiated with respect to their lipid-binding function. We demonstrate that the two proteins bind to diverse lipids with different affinities and therefore are functionally specialized. The observed lipid-binding patterns may be related with the ability of both Hsp70s to induce cell death by binding to a particular plasma-membrane lipid, and the potential of only one of them to promote cell survival by binding to a specific lysosomal-membrane lipid. These observations reveal that two seemingly identical proteins differentially modulate cellular adaptation and survival by having acquired specialized functions via sequence divergence. Therefore, this study provides an evolutionary paradigm, where promiscuity, specificity, sub- and neo-functionalization orchestrate one of the most conserved systems in nature, the cellular stress-response.

  20. Antifungal-protein production in maize (Zea mays) suspension cultures.

    PubMed

    Perri, Fabio; Della Penna, Serena; Rufini, Francesca; Patamia, Maria; Bonito, Mariantonietta; Angiolella, Letizia; Vitali, Alberto

    2009-04-01

    The growing emergency due to the phenomenon of drug resistance to micro-organisms has pushed forward the search for new potential drug alternatives to those already in use. Plants represent a suitable source of new antifungal molecules, as they produce a series of defensive proteins. Among them are the PRPs (pathogenesis-related proteins), shown to be effective in vitro against human pathogens. An optimized and established cell-suspension culture of maize (Zea mays) was shown to constitutively secrete in the medium a series of PRPs comprising the antifungal protein zeamatin (P33679) with a final yield of approx. 3 mg/litre. The in-vitro-produced zeamatin possessed antifungal activity towards a clinical strain of the human pathogenic yeast Candida albicans, an activity comparable with the one reported for the same protein extracted from maize seeds. Along with zeamatin, other PRPs were expressed: a 9 kDa lipid-transfer protein, a 26 kDa xylanase inhibitor and a new antifungal protein, PR-5. A fast, two-step chromatographic procedure was set up allowing the complete purification of the proteins considered, making this cell line a valuable system for the production of potential antifungal agents in a reliable and easy way.

  1. Complete amino acid sequences of the ribosomal proteins L25, L29 and L31 from the archaebacterium Halobacterium marismortui.

    PubMed

    Hatakeyama, T; Kimura, M

    1988-03-15

    Ribosomal proteins were extracted from 50S ribosomal subunits of the archaebacterium Halobacterium marismortui by decreasing the concentration of Mg2+ and K+, and the proteins were separated and purified by ion-exchange column chromatography on DEAE-cellulose. Ten proteins were purified to homogeneity and three of these proteins were subjected to sequence analysis. The complete amino acid sequences of the ribosomal proteins L25, L29 and L31 were established by analyses of the peptides obtained by enzymatic digestion with trypsin, Staphylococcus aureus protease, chymotrypsin and lysylendopeptidase. Proteins L25, L29 and L31 consist of 84, 115 and 95 amino acid residues with the molecular masses of 9472 Da, 12293 Da and 10418 Da respectively. A comparison of their sequences with those of other large-ribosomal-subunit proteins from other organisms revealed that protein L25 from H. marismortui is homologous to protein L23 from Escherichia coli (34.6%), Bacillus stearothermophilus (41.8%), and tobacco chloroplasts (16.3%) as well as to protein L25 from yeast (38.0%). Proteins L29 and L31 do not appear to be homologous to any other ribosomal proteins whose structures are so far known.

  2. Sequence and structural implications of a bovine corneal keratan sulfate proteoglycan core protein. Protein 37B represents bovine lumican and proteins 37A and 25 are unique

    NASA Technical Reports Server (NTRS)

    Funderburgh, J. L.; Funderburgh, M. L.; Brown, S. J.; Vergnes, J. P.; Hassell, J. R.; Mann, M. M.; Conrad, G. W.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    Amino acid sequence from tryptic peptides of three different bovine corneal keratan sulfate proteoglycan (KSPG) core proteins (designated 37A, 37B, and 25) showed similarities to the sequence of a chicken KSPG core protein lumican. Bovine lumican cDNA was isolated from a bovine corneal expression library by screening with chicken lumican cDNA. The bovine cDNA codes for a 342-amino acid protein, M(r) 38,712, containing amino acid sequences identified in the 37B KSPG core protein. The bovine lumican is 68% identical to chicken lumican, with an 83% identity excluding the N-terminal 40 amino acids. Location of 6 cysteine and 4 consensus N-glycosylation sites in the bovine sequence were identical to those in chicken lumican. Bovine lumican had about 50% identity to bovine fibromodulin and 20% identity to bovine decorin and biglycan. About two-thirds of the lumican protein consists of a series of 10 amino acid leucine-rich repeats that occur in regions of calculated high beta-hydrophobic moment, suggesting that the leucine-rich repeats contribute to beta-sheet formation in these proteins. Sequences obtained from 37A and 25 core proteins were absent in bovine lumican, thus predicting a unique primary structure and separate mRNA for each of the three bovine KSPG core proteins.

  3. Palisade endings in extraocular eye muscles revealed by SNAP-25 immunoreactivity

    PubMed Central

    Eberhorn, Andreas C; Horn, Anja KE; Eberhorn, Nicola; Fischer, Petra; Boergen, Klaus-Peter; Büttner-Ennever, Jean A

    2005-01-01

    Palisade endings form a cuff of nerve terminals around the tip of muscle fibres. They are found only in extraocular muscles, but no definite evidence for their role in eye movements has been established. Palisade endings have been reported in all species so far investigated except the rat. In this study we demonstrate that antibodies against SNAP-25, the synaptosomal associated protein of 25 kDa, reliably visualize the complete motor, sensory and autonomic innervation of the extraocular muscles in human, monkey and rat. The SNAP-25 antibody can be combined with other immunofluorescence procedures, and is used here to study properties of palisade endings. With SNAP-25 immunolabelling putative palisade endings are identified in the rat for the first time. They are not well branched, but fulfil several criteria of palisade endings, being associated with non-twitch fibres as shown by double labelling with ‘myosin heavy chain slow-twitch’ antibodies. The putative palisade endings of the rat lack α-bungarotoxin binding, which implies that these synapses are sensory. If palisade endings are sensory then they could function as an eye muscle proprioceptor. They seem to be a general feature of all vertebrate eye muscles, unlike the other two extraocular proprioceptors, muscle spindles and Golgi tendon organs, the presence of which varies widely between species. PMID:15733303

  4. Coat protein expression strategy of oat blue dwarf virus.

    PubMed

    Edwards, Michael C; Weiland, John J

    2014-02-01

    Oat blue dwarf virus (OBDV) is a member of the genus Marafivirus whose genome encodes a 227 kDa polyprotein (p227) ostensibly processed post-translationally into its functional components. Encoded near the 3' terminus and coterminal with the p227 ORF are ORFs specifying major and minor capsid proteins (CP). Since the CP expression strategy of marafiviruses has not been thoroughly investigated, we produced a series of point mutants in the OBDV CP encoding gene and examined expression in protoplasts. Results support a model in which the 21 kDa major CP is the product of direct translation of a sgRNA, while the 24 kDa minor CP is a cleavage product derived from both the polyprotein and a larger ~26 kDa precursor translated directly from the sgRNA. Cleavage occurs at an LXG[G/A] motif conserved in many viruses that use papain-like proteases for polyprotein processing and protection against degradation via the ubiquitin-proteasome system. Published by Elsevier Inc.

  5. Assembly of the intrinsic factor domains and oligomerization of the protein in the presence of cobalamin.

    PubMed

    Fedosov, Sergey N; Fedosova, Natalya U; Berglund, Lars; Moestrup, Søren K; Nexø, Ebba; Petersen, Torben E

    2004-11-30

    Human intrinsic factor (IF) was purified from the recombinant plant Arabidopsis thaliana by affinity chromatography. Cobalamin (Cbl) saturated protein was separated by gel filtration into peaks I and II, which contained according to SDS electrophoresis the 50 kDa full-length protein IF(50) and a mixture of two fragments, respectively. Two components of peak II were identified as the 30 kDa N-terminal peptide IF(30) and the 20 kDa C-terminal glycopeptide IF(20). Measurements of M(w) under the nondenaturing conditions were conducted by static light scattering. They revealed 100 kDa IF dimers in peak I, whereas 50 kDa cleaved monomers were found in peak II. The protein devoid of Cbl dissociated to the elementary units incapable of association in the absence of Cbl. The individual proteolytic fragments bound Cbl at high concentration of the ligand; however, neither IF(30).Cbl nor IF(20).Cbl oligomerized. A mixture of two fragments IF(30) + IF(20) and Cbl produced a firm complex, IF(30+20).Cbl, which could not associate to dimers. In contrast to IF(30+20).Cbl, the saturated full-length monomers IF(50).Cbl dimerized with K(d) approximately 1 microM. We suggest a two-domain organization of the full-length protein, where two distant units, IF(30) and IF(20), can be assembled only by Cbl. They are connected by a protease-sensitive link, whose native structure is likely to be important for dimerization. However, linkage between two domains is not compulsory for Cbl binding. Advantages of the two-domain structure of IF are discussed.

  6. Th1-stimulatory polyproteins of soluble Leishmania donovani promastigotes ranging from 89.9 to 97.1 kDa offers long-lasting protection against experimental visceral leishmaniasis.

    PubMed

    Kumari, Shraddha; Samant, Mukesh; Misra, Pragya; Khare, Prashant; Sisodia, Brijesh; Shasany, Ajit K; Dube, Anuradha

    2008-10-23

    Our earlier studies identified a fraction (F2) of Leishmania donovani soluble promastigote antigen belonging to 97.4-68 kDa for its ability to stimulate Th1-type cellular responses in cured visceral leishmaniasis (VL) patients as well as in cured hamsters. A further fractionation of F2-fraction into seven subfractions (F2.1-F2.7) and re-assessment for their immunostimulatory responses revealed that out of these, only four (F2.4-F2.7) belonging to 89.9-97.1 kDa, stimulated remarkable Th1-type cellular responses either individually or in a pooled form (P4-7). In this study these potential subfractions were further assessed for their prophylactic potential in combination with BCG against L. donovani challenge in hamsters. Optimum parasite inhibition ( approximately 99%) was obtained in hamsters vaccinated with pooled subfractions and they survived for 1 year. The protection was further supported by remarkable lymphoproliferative, IFN-gamma and IL-12 responses along with profound delayed type hypersensitivity and increased levels of Leishmania-specific IgG2 antibody as observed on days 45, 90 and 120 post-challenge suggesting that a successful subunit vaccine against VL may require multiple Th1-immunostimulatory proteins. MALDI-TOF-MS/MS analysis of these subfractions further revealed that of the 19 identified immunostimulatory proteins, Elongation factor-2, p45, Heat shock protein-70/83, Aldolase, Enolase, Triosephosphate isomerase, Disulfideisomerase and Calreticulin were the major ones in these subfractions.

  7. Characterization of the interactions between protein and carbon black.

    PubMed

    Chen, Tzu-Tao; Chuang, Kai-Jen; Chiang, Ling-Ling; Chen, Chun-Chao; Yeh, Chi-Tai; Wang, Liang-Shun; Gregory, Clive; Jones, Tim; BéruBé, Kelly; Lee, Chun-Nin; Chuang, Hsiao-Chi; Cheng, Tsun-Jen

    2014-01-15

    A considerable amount of studies have been conducted to investigate the interactions of biological fluids with nanoparticle surfaces, which exhibit a high affinity for proteins and particles. However, the mechanisms underlying these interactions have not been elucidated, particularly as they relate to human health. Using bovine serum albumin (BSA) and mice bronchoalveolar lavage fluid (BALF) as models for protein-particle conjugates, we characterized the physicochemical modifications of carbon blacks (CB) with 23nm or 65nm in diameter after protein treatment. Adsorbed BALF-containing proteins were quantified and identified by pathways, biological analyses and protein classification. Significant modifications of the physicochemistry of CB were induced by the addition of BSA. Enzyme modulators and hydrolase predominately interacted with CB, with protein-to-CB interactions that were associated with the coagulation pathways. Additionally, our results revealed that an acute-phase response could be activated by these proteins. With regard to human health, the present study revealed that the CB can react with proteins (∼55kDa and 70kDa) after inhalation and may modify the functional structures of lung proteins, leading to the activation of acute-inflammatory responses in the lungs. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Sulfatide-Hsp70 Interaction Promotes Hsp70 Clustering and Stabilizes Binding to Unfolded Protein

    PubMed Central

    Harada, Yoichiro; Sato, Chihiro; Kitajima, Ken

    2015-01-01

    The 70-kDa heat shock protein (Hsp70), one of the major stress-inducible molecular chaperones, is localized not only in the cytosol, but also in extracellular milieu in mammals. Hsp70 interacts with various cell surface glycolipids including sulfatide (3'-sulfogalactosphingolipid). However, the molecular mechanism, as well as the biological relevance, underlying the glycolipid-Hsp70 interaction is unknown. Here we report that sulfatide promotes Hsp70 oligomerization through the N-terminal ATPase domain, which stabilizes the binding of Hsp70 to unfolded protein in vitro. We find that the Hsp70 oligomer has apparent molecular masses ranging from 440 kDa to greater than 669 kDa. The C-terminal peptide-binding domain is dispensable for the sulfatide-induced oligomer formation. The oligomer formation is impaired in the presence of ATP, while the Hsp70 oligomer, once formed, is unable to bind to ATP. These results suggest that sulfatide locks Hsp70 in a high-affinity state to unfolded proteins by clustering the peptide-binding domain and blocking the binding to ATP that induces the dissociation of Hsp70 from protein substrates. PMID:25989600

  9. The whispering gallery mode biosensor: label-free detection from virus to single protein

    NASA Astrophysics Data System (ADS)

    Holler, S.; Dantham, V. R.; Keng, D.; Kolchenko, V.; Arnold, S.; Mulroe, Brigid; Paspaley-Grbavac, M.

    2014-08-01

    The whispering gallery mode (WGM) biosensor is a micro-optical platform capable of sensitive label-free detection of biological particles. Described by the reactive sensing principle (RSP), this analytic formulation quantifies the response of the system to the adsorption of bioparticles. Guided by the RSP, the WGM biosensor enabling from detection of virus (e.g., Human Papillomavirus, HPV) to the ultimate goal of single protein detection. The latter was derived from insights into the RSP, which resulted in the development of a hybrid plasmonic WGM biosensor, which has recently demonstrated detection of individual protein cancer markers. Enhancements from bound gold nanoparticles provide the sensitivity to detect single protein molecules (66 kDa) with good signal-to-noise (S/N > 10), and project that detection of proteins as small as 5 kDa.

  10. Purification, identification and preliminary crystallographic studies of an allergenic protein from Lathyrus sativus

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Qureshi, Insaf A.; Sethi, Dhruv K.; Salunke, Dinakar M., E-mail: dinakar@nii.res.in

    2006-09-01

    A 24 kDa protein was purified from the seeds of L. sativus by ammonium sulfate fractionation and ion-exchange chromatography. Crystals were obtained by the hanging-drop vapour-diffusion method. A 24 kDa protein was purified from the seeds of Lathyrus sativus by ammonium sulfate fractionation and ion-exchange chromatography. The N-terminal amino-acid sequence showed significant homology with the 2S albumin class of seed storage proteins. The protein showed 85% sequence homology with the seed albumin of Pisum sativum within the 40 N-terminal residues. Crystals were obtained by the hanging-drop vapour-diffusion method. The crystals belonged to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cellmore » parameters a = 43.5, b = 82.7, c = 153.4 Å.« less

  11. An endogenously produced fragment of cardiac myosin-binding protein C is pathogenic and can lead to heart failure.

    PubMed

    Razzaque, Md Abdur; Gupta, Manish; Osinska, Hanna; Gulick, James; Blaxall, Burns C; Robbins, Jeffrey

    2013-08-16

    A stable 40-kDa fragment is produced from cardiac myosin-binding protein C when the heart is stressed using a stimulus, such as ischemia-reperfusion injury. Elevated levels of the fragment can be detected in the diseased mouse and human heart, but its ability to interfere with normal cardiac function in the intact animal is unexplored. To understand the potential pathogenicity of the 40-kDa fragment in vivo and to investigate the molecular pathways that could be targeted for potential therapeutic intervention. We generated cardiac myocyte-specific transgenic mice using a Tet-Off inducible system to permit controlled expression of the 40-kDa fragment in cardiomyocytes. When expression of the 40-kDa protein is induced by crossing the responder animals with tetracycline transactivator mice under conditions in which substantial quantities approximating those observed in diseased hearts are reached, the double-transgenic mice subsequently experience development of sarcomere dysgenesis and altered cardiac geometry, and the heart fails between 12 and 17 weeks of age. The induced double-transgenic mice had development of cardiac hypertrophy with myofibrillar disarray and fibrosis, in addition to activation of pathogenic MEK-ERK pathways. Inhibition of MEK-ERK signaling was achieved by injection of the mitogen-activated protein kinase (MAPK)/ERK inhibitor U0126. The drug effectively improved cardiac function, normalized heart size, and increased probability of survival. These results suggest that the 40-kDa cardiac myosin-binding protein C fragment, which is produced at elevated levels during human cardiac disease, is a pathogenic fragment that is sufficient to cause hypertrophic cardiomyopathy and heart failure.

  12. Major immunogenic proteins of phocid herpes-viruses and their relationships to proteins of canine and feline herpesviruses.

    PubMed

    Harder, T C; Harder, M; de Swart, R L; Osterhaus, A D; Liess, B

    1998-04-01

    The immunogenic proteins of cells infected with the alpha- or the gamma-herpesvirus of seals, phocid herpesvirus-1 and -2 (PhHV-1, -2), were examined in radioimmunoprecipitation assays as a further step towards the development of a PhHV-1 vaccine. With sera obtained from convalescent seals of different species or murine monoclonal antibodies (Mabs), at least seven virus-induced glycoproteins were detected in lysates of PhHV-1-infected CrFK cells. A presumably disulphide-linked complex composed of glycoproteins of 59, 67 and 113/120 kDa, expressed on the surface of infected cells, was characterized as a major immunogenic infected cell protein of PhHV-1. This glycoprotein complex has previously been identified as the proteolytically cleavable glycoprotein B homologue of PhHV-1 (14). At least three distinct neutralization-relevant epitopes were operationally mapped, by using Mabs, on the glycoprotein B of PhHV-1. Among the infected cell proteins of the antigenically closely related feline and canine herpesvirus, the glycoprotein B equivalent proved to be the most highly conserved glycoprotein. Sera obtained from different seal species from Arctic, Antarctic, and European habitats did not precipitate uniform patterns of infected cell proteins from PhHV-1-infected cell lysates although similar titres of neutralizing antibodies were displayed. Thus, antigenic differences among the alphaherpesvirus species prevalent in the different pinniped populations cannot be excluded. PhHV-2 displayed a different pattern of infected cell proteins and only limited cross-reactivity to PhHV-1 at the protein level was detected, which is in line with its previous classification as a distinct species, based on nucleotide sequence analysis, of the gammaherpesvirus linenge. A Mab raised against PhHV-2 and specific for a major glycoprotein of 117 kDa, cross reacted with the glycoprotein B of PhHV-1. The 117-kDa glycoprotein could represent the uncleaved PhHV-2 glycoprotein B homologue.

  13. Chronic high fat, high cholesterol supplementation decreases 18 kDa Translocator Protein binding capacity in association with increased oxidative stress in rat liver and aorta.

    PubMed

    Dimitrova-Shumkovska, Jasmina; Veenman, Leo; Ristoski, Trpe; Leschiner, Svetlana; Gavish, Moshe

    2010-03-01

    It is well known that high fat and high cholesterol levels present a contributing factor to pathologies including fatty liver and atherosclerosis. Oxidative stress is also considered to play a role in these pathologies. The 18 kDa Translocator Protein (TSPO), formerly known as the peripheral-type benzodiazepine receptor, is known to be involved in cholesterol metabolism, oxidative stress, and cardiovascular pathology. We applied a high fat high cholesterol atherogenic (HFHC) diet to rats to study correlations between cardiovascular and liver pathology, oxidative stress, and TSPO expression in the liver and the cardiovascular system. This study corroborates the presence of increased oxidative stress markers and decreased anti-oxidants in liver and aorta. In addition, it appeared that induction of oxidative stress in the liver and aorta by atherogenic HFHC diet was accompanied by a reduction in TSPO binding density in both these tissues. Our data suggest that involvement of TSPO in oxidative stress and ROS generation, as reported in other studies, may also take part in atherogenesis as induced by HFHC diet. Presently, it is not clear whether this TSPO response is compensatory for the stress induced by HFHC diet or is a participant in the induction of oxidative stress. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  14. Effects of autoclaving and high pressure on allergenicity of hazelnut proteins

    PubMed Central

    2012-01-01

    Background Hazelnut is reported as a causative agent of allergic reactions. However it is also an edible nut with health benefits. The allergenic characteristics of hazelnut-samples after autoclaving (AC) and high-pressure (HHP) processing have been studied and are also presented here. Previous studies demonstrated that AC treatments were responsible for structural transformation of protein structure motifs. Thus, structural analyses of allergen proteins from hazelnut were carried out to observe what is occurring in relation to the specific-IgE recognition of the related allergenic proteins. The aims of this work are to evaluate the effect of AC and HHP processing on hazelnut in vitro allergenicity using human-sera and to analyse the complexity of hazelnut allergen-protein structures. Methods Hazelnut-samples were subjected to AC and HHP processing. The specific IgE- reactivity was studied in 15 allergic clinic-patients via western blotting analyses. A series of homology-based-bioinformatics 3D-models (Cora 1, Cora 8, Cora 9 and Cora 11) were generated for the antigens included in the study to analyse the co mplexity of their protein structure. This study is supported by the Declaration of Helsinki and subsequent ethical guidelines. Results A severe reduction in vitro in allergenicity to hazelnut after AC processing was observed in the allergic clinic-patients studied. The specific-IgE binding of some of the described immunoreactive hazelnut protein-bands: Cora 1 ~18KDa, Cora 8 ~9KDa, Cora 9 ~35-40KDa and Cora 11 ~47-48 KDa decreases. Furthermore a relevant glycosylation was assigned and visualized via structural analysis of proteins (3D-modelling) for the first time in the protein-allergen Cora 11 showing a new role which could open a new door for allergenicity-unravellings. Conclusion Hazelnut allergenicity-studies in vivo via Prick-Prick and other means using AC processing are crucial to verify the data we observed via in vitro analyses. Glycosylation studies

  15. Milrinone Relaxes Pulmonary Veins in Guinea Pigs and Humans

    PubMed Central

    Rieg, Annette D.; Suleiman, Said; Perez-Bouza, Alberto; Braunschweig, Till; Spillner, Jan W.; Schröder, Thomas; Verjans, Eva; Schälte, Gereon; Rossaint, Rolf; Uhlig, Stefan; Martin, Christian

    2014-01-01

    Introduction The phosphodiesterase-III inhibitor milrinone improves ventricular contractility, relaxes pulmonary arteries and reduces right ventricular afterload. Thus, it is used to treat heart failure and pulmonary hypertension (PH). However, its action on pulmonary veins (PVs) is not defined, although particularly PH due to left heart disease primarily affects the pulmonary venous bed. We examined milrinone-induced relaxation in PVs from guinea pigs (GPs) and humans. Material and Methods Precision-cut lung slices (PCLS) were prepared from GPs or from patients undergoing lobectomy. Milrinone-induced relaxation was studied by videomicroscopy in naïve PVs and in PVs pre-constricted with the ETA-receptor agonist BP0104. Baseline luminal area was defined as 100%. Intracellular cAMP was measured by ELISA and milrinone-induced changes of segmental vascular resistances were studied in the GP isolated perfused lung (IPL). Results In the IPL (GP), milrinone (10 µM) lowered the postcapillary resistance of pre-constricted vessels. In PCLS (GP), milrinone relaxed naïve and pre-constricted PVs (120%) and this relaxation was attenuated by inhibition of protein kinase G (KT 5823), adenyl cyclase (SQ 22536) and protein kinase A (KT 5720), but not by inhibition of NO-synthesis (L-NAME). In addition, milrinone-induced relaxation was dependent on the activation of KATP-, BKCa 2+- and Kv-channels. Human PVs also relaxed to milrinone (121%), however only if pre-constricted. Discussion Milrinone relaxes PVs from GPs and humans. In GPs, milrinone-induced relaxation is based on KATP-, BKCa 2+- and Kv-channel-activation and on cAMP/PKA/PKG. The relaxant properties of milrinone on PVs lead to reduced postcapillary resistance and hydrostatic pressures. Hence they alleviate pulmonary edema and suggest beneficial effects of milrinone in PH due to left heart disease. PMID:24498166

  16. Milrinone relaxes pulmonary veins in guinea pigs and humans.

    PubMed

    Rieg, Annette D; Suleiman, Said; Perez-Bouza, Alberto; Braunschweig, Till; Spillner, Jan W; Schröder, Thomas; Verjans, Eva; Schälte, Gereon; Rossaint, Rolf; Uhlig, Stefan; Martin, Christian

    2014-01-01

    The phosphodiesterase-III inhibitor milrinone improves ventricular contractility, relaxes pulmonary arteries and reduces right ventricular afterload. Thus, it is used to treat heart failure and pulmonary hypertension (PH). However, its action on pulmonary veins (PVs) is not defined, although particularly PH due to left heart disease primarily affects the pulmonary venous bed. We examined milrinone-induced relaxation in PVs from guinea pigs (GPs) and humans. Precision-cut lung slices (PCLS) were prepared from GPs or from patients undergoing lobectomy. Milrinone-induced relaxation was studied by videomicroscopy in naïve PVs and in PVs pre-constricted with the ETA-receptor agonist BP0104. Baseline luminal area was defined as 100%. Intracellular cAMP was measured by ELISA and milrinone-induced changes of segmental vascular resistances were studied in the GP isolated perfused lung (IPL). In the IPL (GP), milrinone (10 µM) lowered the postcapillary resistance of pre-constricted vessels. In PCLS (GP), milrinone relaxed naïve and pre-constricted PVs (120%) and this relaxation was attenuated by inhibition of protein kinase G (KT 5823), adenyl cyclase (SQ 22536) and protein kinase A (KT 5720), but not by inhibition of NO-synthesis (L-NAME). In addition, milrinone-induced relaxation was dependent on the activation of K ATP-, BK Ca (2+)- and Kv-channels. Human PVs also relaxed to milrinone (121%), however only if pre-constricted. Milrinone relaxes PVs from GPs and humans. In GPs, milrinone-induced relaxation is based on K ATP-, BK Ca (2+)- and Kv-channel-activation and on cAMP/PKA/PKG. The relaxant properties of milrinone on PVs lead to reduced postcapillary resistance and hydrostatic pressures. Hence they alleviate pulmonary edema and suggest beneficial effects of milrinone in PH due to left heart disease.

  17. Activity of maize transglutaminase overexpressed in Escherichia coli inclusion bodies: an alternative to protein refolding.

    PubMed

    Carvajal, Patricia; Gibert, Jordi; Campos, Nefertiti; Lopera, Oriol; Barberà, Eduard; Torné, Jose M; Santos, Mireya

    2011-01-01

    Transglutaminases (TGases) catalyze protein post-translational modification by ε-(γ-glutamyl) links and covalent polyamine conjugation. In plants, this enzyme is poorly characterized and only the maize plastidial TGase gene (tgz) has been cloned. The tgz gene (Patent WWO03102128) had been subcloned and overexpressed in Escherichia coli cells, and the recombinant protein (TGZp) was present mainly in inclusion bodies (IB) fraction. In this work, after overexpression of TGZ15p and SDS-PAGE IB fraction analysis, bands about 65 and 56 kDa were obtained. Western blot, alkylation and MALDI-TOF/TOF analyses indicated that the 56 kDa band corresponded to a truncated sequence from the native TGZ15p (expected MW 65 kDa), by elimination of a chloroplast signal peptide fragment during expression processing. So that large-scale protein production and protein crystallization can be applied, we characterized the TGZ15p enzyme activity in the IB protein fraction, with and without refolding. Results indicate that it presented the biochemical characteristics of other described TGases, showing a certain plant-substrate preference. Solubilization of the IB fraction with Triton X-100 as nondenaturing detergent yielded active TGZ without the need for refolding, giving activity values comparable to those of the refolded protein, indicating that this is a valuable, faster way to obtain TGZ active protein. Copyright © 2011 American Institute of Chemical Engineers (AIChE).

  18. Crystal structure of the YDR533c S. cerevisiae protein, a class II member of the Hsp31 family.

    PubMed

    Graille, Marc; Quevillon-Cheruel, Sophie; Leulliot, Nicolas; Zhou, Cong-Zhao; Li de la Sierra Gallay, Ines; Jacquamet, Lilian; Ferrer, Jean-Luc; Liger, Dominique; Poupon, Anne; Janin, Joel; van Tilbeurgh, Herman

    2004-05-01

    The ORF YDR533c from Saccharomyces cerevisiae codes for a 25.5 kDa protein of unknown biochemical function. Transcriptome analysis of yeast has shown that this gene is activated in response to various stress conditions together with proteins belonging to the heat shock family. In order to clarify its biochemical function, we determined the crystal structure of YDR533c to 1.85 A resolution by the single anomalous diffraction method. The protein possesses an alpha/beta hydrolase fold and a putative Cys-His-Glu catalytic triad common to a large enzyme family containing proteases, amidotransferases, lipases, and esterases. The protein has strong structural resemblance with the E. coli Hsp31 protein and the intracellular protease I from Pyrococcus horikoshii, which are considered class I and class III members of the Hsp31 family, respectively. Detailed structural analysis strongly suggests that the YDR533c protein crystal structure is the first one of a class II member of the Hsp31 family.

  19. Diphenylpyrazoles as Replication Protein A inhibitors

    DOE PAGES

    Waterson, Alex G.; Kennedy, J. Phillip; Patrone, James D.; ...

    2014-11-11

    Replication Protein A is the primary eukaryotic ssDNA binding protein that has a central role in initiating the cellular response to DNA damage. RPA recruits multiple proteins to sites of DNA damage via the N-terminal domain of the 70 kDa subunit (RPA70N). Here we describe the optimization of a diphenylpyrazole carboxylic acid series of inhibitors of these RPA–protein interactions. Lastly, we evaluated substituents on the aromatic rings as well as the type and geometry of the linkers used to combine fragments, ultimately leading to submicromolar inhibitors of RPA70N protein–protein interactions.

  20. The stylar 120 kDa glycoprotein is required for S-specific pollen rejection in Nicotiana.

    PubMed

    Hancock, C Nathan; Kent, Lia; McClure, Bruce A

    2005-09-01

    S-RNase participates in at least three mechanisms of pollen rejection. It functions in S-specific pollen rejection (self-incompatibility) and in at least two distinct interspecific mechanisms of pollen rejection in Nicotiana. S-specific pollen rejection and rejection of pollen from Nicotiana plumbaginifolia also require additional stylar proteins. Transmitting-tract-specific (TTS) protein, 120 kDa glycoprotein (120K) and pistil extensin-like protein III (PELP III) are stylar glycoproteins that bind S-RNase in vitro and are also known to interact with pollen. Here we tested whether these glycoproteins have a direct role in pollen rejection. 120K shows the most polymorphism in size between Nicotiana species. Larger 120K-like proteins are often correlated with S-specific pollen rejection. Sequencing results suggest that the polymorphism primarily reflects differences in glycosylation, although indels also occur in the predicted polypeptides. Using RNA interference (RNAi), we suppressed expression of 120K to determine if it is required for S-specific pollen rejection. Transgenic SC N. plumbaginifolia x SI Nicotiana alata (S105S105 or SC10SC10) hybrids with no detectable 120K were unable to perform S-specific pollen rejection. Thus, 120K has a direct role in S-specific pollen rejection. However, suppression of 120K had no effect on rejection of N. plumbaginifolia pollen. In contrast, suppression of HT-B, a factor previously implicated in S-specific pollen rejection, disrupts rejection of N. plumbaginifolia pollen. Thus, S-specific pollen rejection and rejection of N. plumbaginifolia pollen are mechanistically distinct, because they require different non-S-RNase factors.

  1. Frontotemporal dysregulation of the SNARE protein interactome is associated with faster cognitive decline in old age.

    PubMed

    Ramos-Miguel, Alfredo; Jones, Andrea A; Sawada, Ken; Barr, Alasdair M; Bayer, Thomas A; Falkai, Peter; Leurgans, Sue E; Schneider, Julie A; Bennett, David A; Honer, William G

    2018-06-01

    The molecular underpinnings associated with cognitive reserve remain poorly understood. Because animal models fail to fully recapitulate the complexity of human brain aging, postmortem studies from well-designed cohorts are crucial to unmask mechanisms conferring cognitive resistance against cumulative neuropathologies. We tested the hypothesis that functionality of the SNARE protein interactome might be an important resilience factor preserving cognitive abilities in old age. Cognition was assessed annually in participants from the Rush "Memory and Aging Project" (MAP), a community-dwelling cohort representative of the overall aging population. Associations between cognition and postmortem neurochemical data were evaluated in functional assays quantifying various species of the SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) machinery in samples from the inferior temporal (IT, n = 154) and middle-frontal (MF, n = 174) gyri. Using blue-native gel electrophoresis, we isolated and quantified several types of complexes containing the three SNARE proteins (syntaxin-1, SNAP25, VAMP), as well as the GABAergic/glutamatergic selectively expressed complexins-I/II (CPLX1/2), in brain tissue homogenates and reconstitution assays with recombinant proteins. Multivariate analyses revealed significant associations between IT and MF neurochemical data (SNARE proteins and/or complexes), and multiple age-related neuropathologies, as well as with multiple cognitive domains of MAP participants. Controlling for demographic variables, neuropathologic indices and total synapse density, we found that temporal 150-kDa SNARE species (representative of pan-synaptic functionality) and frontal CPLX1/CPLX2 ratio of 500-kDa heteromeric species (representative of inhibitory/excitatory input functionality) were, among all the immunocharacterized complexes, the strongest predictors of cognitive function nearest death. Interestingly, these two neurochemical

  2. LINE-1 ORF1 protein localizes in stress granules with other RNA-binding proteins, including components of RNA interference RNA-induced silencing complex.

    PubMed

    Goodier, John L; Zhang, Lili; Vetter, Melissa R; Kazazian, Haig H

    2007-09-01

    LINE-1 retrotransposons constitute one-fifth of human DNA and have helped shape our genome. A full-length L1 encodes a 40-kDa RNA-binding protein (ORF1p) and a 150-kDa protein (ORF2p) with endonuclease and reverse transcriptase activities. ORF1p is distinctive in forming large cytoplasmic foci, which we identified as cytoplasmic stress granules. A phylogenetically conserved central region of the protein is critical for wild-type localization and retrotransposition. Yeast two-hybrid screens revealed several RNA-binding proteins that coimmunoprecipitate with ORF1p and colocalize with ORF1p in foci. Two of these proteins, YB-1 and hnRNPA1, were previously reported in stress granules. We identified additional proteins associated with stress granules, including DNA-binding protein A, 9G8, and plasminogen activator inhibitor RNA-binding protein 1 (PAI-RBP1). PAI-RBP1 is a homolog of VIG, a part of the Drosophila melanogaster RNA-induced silencing complex (RISC). Other RISC components, including Ago2 and FMRP, also colocalize with PAI-RBP1 and ORF1p. We suggest that targeting ORF1p, and possibly the L1 RNP, to stress granules is a mechanism for controlling retrotransposition and its associated genetic and cellular damage.

  3. Identification of a major yolk protein as an allergen in sea urchin roe.

    PubMed

    Yamasaki, Ayako; Higaki, Hiromi; Nakashima, Keiko; Yamamoto, Osamu; Hein, Kyaw Zaw; Takahashi, Hitoshi; Chinuki, Yuko; Morita, Eishin

    2010-05-01

    Anaphylaxis after eating sea urchin roe has been reported. However, its major allergens have not yet been identified. The aim of this study was to identify the major allergens of sea urchin roe. Proteins of sea urchin roe were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and two-dimensional electrophoresis (2-DE). An immunoglobulin (Ig)E-binding protein was detected by immunoblotting using the patient's serum. An allergen isolated from 2DE-gel was identified by peptide mass fingerprinting using matrix-assisted laser desorption/ionization-time of flight-mass spectrometry. Immunoblot analysis of sea urchin extracts showed that a 160-kDa protein at pI 6-7 was recognized by the patient's IgE. Peptide mass fingerprint analysis revealed that the protein was the major yolk protein (152 kDa, pI 6.9) of sea urchins. The results show that a major allergen of sea urchin roe is the major yolk protein.

  4. Mycobacterial r32-kDa antigen-specific T-cell responses correlate with successful treatment and a heightened anti-microbial response in human leprosy patients.

    PubMed

    Neela, Venkata Sanjeev Kumar; Devalraju, Kamakshi Prudhula; Pydi, Satya Sudheer; Sunder, Sharada Ramaseri; Adiraju, Kameswara Rao; Singh, Surya Satyanarayana; Anandaraj, M P J S; Valluri, Vijaya Lakshmi

    2016-09-01

    Immunological characterization of mycobacterial peptides may help not only in the preparation of a vaccine for leprosy but also in developing in vitro T-cell assays that could perhaps be used as an in vitro correlate for treatment outcome. The main goal of this study was to evaluate the use of Mycobacterium bovis recombinant 32-kDa protein (r32-kDa) antigen-stimulated T-cell assay as a surrogate marker for treatment outcome and monitor vitamin D receptor (VDR)-mediated anti-microbial responses during multidrug therapy (MDT) in leprosy. Newly diagnosed tuberculoid and lepromatous leprosy patients were enrolled and followed up during their course of MDT at 6 and 12 months. IFN-γ, IL-10, IL-17 and IL-23 levels in culture supernatants and expression of VDR, TLR2, LL37 and DEFB in r32-kDa-stimulated PBMCs were measured. Controls comprised household contacts (HHCs) and healthy endemic subjects (HCs). Significant differences were observed in the levels of IFN-γ, IL-17, IL-23, VDR and anti-microbial peptides LL37 and DEFB after treatment and when compared with that of HHCs and HCs, respectively. These findings suggest that responses to r32-kDa antigen reflect an improved immunological and anti-microbial response in leprosy patients during therapy, thereby indicating its potential use as an immune correlate in the treatment of leprosy patients. © The Japanese Society for Immunology. 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Expression and characterization of an iron-regulated hemin-binding protein, HbpA, from Leptospira interrogans serovar Lai.

    PubMed

    Asuthkar, Swapna; Velineni, Sridhar; Stadlmann, Johannes; Altmann, Friedrich; Sritharan, Manjula

    2007-09-01

    In an earlier study, based on the ferric enterobactin receptor FepA of Escherichia coli, we identified and modeled a TonB-dependent outer membrane receptor protein (LB191) from the genome of Leptospira interrogans serovar Lai. Based on in silico analysis, we hypothesized that this protein was an iron-dependent hemin-binding protein. In this study, we provide experimental evidence to prove that this protein, termed HbpA (hemin-binding protein A), is indeed an iron-regulated hemin-binding protein. We cloned and expressed the full-length 81-kDa recombinant rHbpA protein and a truncated 55-kDa protein from L. interrogans serovar Lai, both of which bind hemin-agarose. Assay of hemin-associated peroxidase activity and spectrofluorimetric analysis provided confirmatory evidence of hemin binding by HbpA. Immunofluorescence studies by confocal microscopy and the microscopic agglutination test demonstrated the surface localization and the iron-regulated expression of HbpA in L. interrogans. Southern blot analysis confirmed our earlier observation that the hbpA gene was present only in some of the pathogenic serovars and was absent in Leptospira biflexa. Hemin-agarose affinity studies showed another hemin-binding protein with a molecular mass of approximately 44 kDa, whose expression was independent of iron levels. This protein was seen in several serovars, including nonpathogenic L. biflexa. Sequence analysis and immunoreactivity with specific antibodies showed this protein to be LipL41.

  6. Biosynthesis of small proteoglycan II (decorin) by chondrocytes and evidence for a procore protein.

    PubMed

    Sawhney, R S; Hering, T M; Sandell, L J

    1991-05-15

    We have studied the biosynthesis of cartilage dermatan sulfate proteoglycan II (DS-PGII) (decorin) using in vitro translation of mRNA to determine the size of the primary gene product and by radiolabeling the protein in the presence of tunicamycin to inhibit the addition of Asn-linked oligosaccharides. Pulse-chase experiments were performed to examine post-translational processing and secretion. Inhibitors of oligosaccharide processing were used to determine whether DS-PGII molecules containing partially processed oligosaccharides could become proteoglycans and be secreted. Cell-free translation of sucrose gradient-fractionated RNA and subsequent immunoprecipitation of the core protein confirmed that the functional translated mRNA is in the size range of the two mRNA species observed by hybridization of chondrocyte RNA with a bone PGII cloned probe and that the translation product is a single protein with an apparent molecular mass of 42 kDa. Digestion of the intact proteoglycan (average molecular mass = 103 kDa) with chondroitinase ABC or AC results in an approximately 48-49-kDa product. Chondrocytes treated with tunicamycin to inhibit Asn-linked oligosaccharide addition synthesize and secrete a glycosaminoglycan (GAG)-substituted proteoglycan (average molecular mass = 86 kDa), yielding a 42-kDa core protein after chondroitinase ABC digestion, showing that Asn-linked oligosaccharides are not required for the addition of GAG chains or secretion. Following a short pulse (10 min) of [3H]leucine, three glycosylated forms of the DS-PGII core protein were observed, one of which is likely to be the precursor form of PGII predicted by the implied protein sequence of both bovine and human cDNA clones. Following the apparent cleavage of the propeptide, GAG-substituted intracellular core protein is detectable. Susceptibility to endoglycosidase H indicates that approximately one-third of the secreted core protein contains exclusively complex-type Asn-linked oligosaccharides

  7. TRIM25 Is Required for the Antiviral Activity of Zinc Finger Antiviral Protein

    PubMed Central

    Zheng, Xiaojiao; Wang, Xinlu; Tu, Fan; Wang, Qin; Fan, Zusen

    2017-01-01

    ABSTRACT Zinc finger antiviral protein (ZAP) is a host factor that specifically inhibits the replication of certain viruses by binding to viral mRNAs and repressing the translation and/or promoting the degradation of target mRNA. In addition, ZAP regulates the expression of certain cellular genes. Here, we report that tripartite motif-containing protein 25 (TRIM25), a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 abolished ZAP's antiviral activity. The E3 ligase activity of TRIM25 is required for this regulation. TRIM25 mediated ZAP ubiquitination, but the ubiquitination of ZAP itself did not seem to be required for its antiviral activity. Downregulation of endogenous ubiquitin or overexpression of the deubiquitinase OTUB1 impaired ZAP's activity. We provide evidence indicating that TRIM25 modulates the target RNA binding activity of ZAP. These results uncover a mechanism by which the antiviral activity of ZAP is regulated. IMPORTANCE ZAP is a host antiviral factor that specifically inhibits the replication of certain viruses, including HIV-1, Sindbis virus, and Ebola virus. ZAP binds directly to target mRNA, and it represses the translation and promotes the degradation of target mRNA. While the mechanisms by which ZAP posttranscriptionally inhibits target RNA expression have been extensively studied, how its antiviral activity is regulated is not very clear. Here, we report that TRIM25, a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 remarkably abolished ZAP's activity. TRIM25 is required for ZAP optimal binding to target mRNA. These results help us to better understand how the antiviral activity of ZAP is regulated. PMID:28202764

  8. TRIM25 Is Required for the Antiviral Activity of Zinc Finger Antiviral Protein.

    PubMed

    Zheng, Xiaojiao; Wang, Xinlu; Tu, Fan; Wang, Qin; Fan, Zusen; Gao, Guangxia

    2017-05-01

    Zinc finger antiviral protein (ZAP) is a host factor that specifically inhibits the replication of certain viruses by binding to viral mRNAs and repressing the translation and/or promoting the degradation of target mRNA. In addition, ZAP regulates the expression of certain cellular genes. Here, we report that tripartite motif-containing protein 25 (TRIM25), a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 abolished ZAP's antiviral activity. The E3 ligase activity of TRIM25 is required for this regulation. TRIM25 mediated ZAP ubiquitination, but the ubiquitination of ZAP itself did not seem to be required for its antiviral activity. Downregulation of endogenous ubiquitin or overexpression of the deubiquitinase OTUB1 impaired ZAP's activity. We provide evidence indicating that TRIM25 modulates the target RNA binding activity of ZAP. These results uncover a mechanism by which the antiviral activity of ZAP is regulated. IMPORTANCE ZAP is a host antiviral factor that specifically inhibits the replication of certain viruses, including HIV-1, Sindbis virus, and Ebola virus. ZAP binds directly to target mRNA, and it represses the translation and promotes the degradation of target mRNA. While the mechanisms by which ZAP posttranscriptionally inhibits target RNA expression have been extensively studied, how its antiviral activity is regulated is not very clear. Here, we report that TRIM25, a ubiquitin E3 ligase, is required for the antiviral activity of ZAP. Downregulation of endogenous TRIM25 remarkably abolished ZAP's activity. TRIM25 is required for ZAP optimal binding to target mRNA. These results help us to better understand how the antiviral activity of ZAP is regulated. Copyright © 2017 American Society for Microbiology.

  9. 3D DOSY-TROSY to determine the translational diffusion coefficient of large protein complexes.

    PubMed

    Didenko, Tatiana; Boelens, Rolf; Rüdiger, Stefan G D

    2011-01-01

    The translational diffusion coefficient is a sensitive parameter to probe conformational changes in proteins and protein-protein interactions. Pulsed-field gradient NMR spectroscopy allows one to measure the translational diffusion with high accuracy. Two-dimensional (2D) heteronuclear NMR spectroscopy combined with diffusion-ordered spectroscopy (DOSY) provides improved resolution and therefore selectivity when compared with a conventional 1D readout. Here, we show that a combination of selective isotope labelling, 2D ¹H-¹³C methyl-TROSY (transverse relaxation-optimised spectroscopy) and DOSY allows one to study diffusion properties of large protein complexes. We propose that a 3D DOSY-heteronuclear multiple quantum coherence (HMQC) pulse sequence, that uses the TROSY effect of the HMQC sequence for ¹³C methyl-labelled proteins, is highly suitable for measuring the diffusion coefficient of large proteins. We used the 20 kDa co-chaperone p23 as model system to test this 3D DOSY-TROSY technique under various conditions. We determined the diffusion coefficient of p23 in viscous solutions, mimicking large complexes of up to 200 kDa. We found the experimental data to be in excellent agreement with theoretical predictions. To demonstrate the use for complex formation, we applied this technique to record the formation of a complex of p23 with the molecular chaperone Hsp90, which is around 200 kDa. We anticipate that 3D DOSY-TROSY will be a useful tool to study conformational changes in large protein complexes.

  10. SNARE proteins synaptobrevin, SNAP-25 and syntaxin are involved in rapid and slow endocytosis at synapses

    PubMed Central

    Xu, Jianhua; Luo, Fujun; Zhang, Zhen; Xue, Lei; Wu, Xinsheng; Chiang, Hsueh-Cheng; Shin, Wonchul; Wu, Ling-Gang

    2013-01-01

    Rapid endocytosis, which takes only a few seconds, is widely observed in secretory cells. Although it is more efficient in recycling vesicles than slow clathrin-mediated endocytosis, its underlying mechanism, thought to be clathrin-independent, is largely unclear. Here we reported that cleavage of three SNARE proteins essential for exocytosis, including synaptobrevin, SNAP-25 and syntaxin, inhibited rapid endocytosis at the calyx of Held nerve terminal, suggesting the involvement of three SNARE proteins in rapid endocytosis. These SNARE proteins were also involved in slow endocytosis. In addition, SNAP-25 and syntaxin facilitated vesicle mobilization to the readily releasable pool, likely via their roles in endocytosis and/or exocytosis. We concluded that both rapid and slow endocytosis share the involvement of SNARE proteins. The dual role of three SNARE proteins in exo- and endocytosis suggests that SNARE proteins may be molecular substrates contributing to the exo-endocytosis coupling, which maintains exocytosis in secretory cells. PMID:23643538

  11. ISOLATION, CHARACTERIZATION AND IMMUNOCHEMICAL STUDIES ON FIBROUS PROTEINS FROM COWRY SHELL (CYPRAEA MONETA, LINNAEUS)

    PubMed Central

    Togun, R.A.; Balogun, R. O.; Adeyemi, D.O.; Esan, T.A.; Oyatogun, G.M; Oziegbe, E.O; Okonji, R. E.; Kuku, A.

    2017-01-01

    Background: Biomaterials are non-drug substances used to treat, enhance or replace functions of body tissues or organs. Natural sources of biomaterials have recently become the focus of several research activities. Cowry shell constitutes one of the most promising natural sources of biomaterials because of its chemical stability, biodegradability and biocompatibility in the body. However, its applications may be limited due to immunogenic and toxic responses that may occur following implantation, hence this study. Materials and Methods: Crude fibrous protein extracted with citrate buffer from pulverised cowry shells (Cypraea moneta (L)), was resolved into two components (CSP1 and CSP2) by gel filtration. Immunological studies were performed with antisera obtained from rabbits by double immunodiffusion and immunoelectrophoresis techniques. Mice treated with the proteins were observed for signs of toxicity and their liver, kidney, lungs and spleen were processed histologically. Results: The native molecular weight of CSP1 and CSP2 determined by gel filtration were 91kDa and 33kDa respectively. CSP1 and CSP2 displayed single bands on SDS-PAGE with subunit molecular weight values of 19kDa and 19.5kDa respectively. Antisera obtained from rabbits immunised with the crude citrate buffer extracts precipitated the antigen in double immunodiffusion tests. Histopathological examinations revealed a dose-dependent damaging effect of the shell proteins on liver, kidney, lung and spleen tissues of the treated mice. Conclusion: This study showed that cowry shells contain fibrous proteins which are immunogenic and toxic in mice at relatively high concentrations, causing visible organ damage without concurrent physical manifestations. PMID:28480388

  12. Lipid, Detergent, and Coomassie Blue G-250 Affect the Migration of Small Membrane Proteins in Blue Native Gels

    PubMed Central

    Crichton, Paul G.; Harding, Marilyn; Ruprecht, Jonathan J.; Lee, Yang; Kunji, Edmund R. S.

    2013-01-01

    Blue native gel electrophoresis is a popular method for the determination of the oligomeric state of membrane proteins. Studies using this technique have reported that mitochondrial carriers are dimeric (composed of two ∼32-kDa monomers) and, in some cases, can form physiologically relevant associations with other proteins. Here, we have scrutinized the behavior of the yeast mitochondrial ADP/ATP carrier AAC3 in blue native gels. We find that the apparent mass of AAC3 varies in a detergent- and lipid-dependent manner (from ∼60 to ∼130 kDa) that is not related to changes in the oligomeric state of the protein, but reflects differences in the associated detergent-lipid micelle and Coomassie Blue G-250 used in this technique. Higher oligomeric state species are only observed under less favorable solubilization conditions, consistent with aggregation of the protein. Calibration with an artificial covalent AAC3 dimer indicates that the mass observed for solubilized AAC3 and other mitochondrial carriers corresponds to a monomer. Size exclusion chromatography of purified AAC3 in dodecyl maltoside under blue native gel-like conditions shows that the mass of the monomer is ∼120 kDa, but appears smaller on gels (∼60 kDa) due to the unusually high amount of bound negatively charged dye, which increases the electrophoretic mobility of the protein-detergent-dye micelle complex. Our results show that bound lipid, detergent, and Coomassie stain alter the behavior of mitochondrial carriers on gels, which is likely to be true for other small membrane proteins where the associated lipid-detergent micelle is large when compared with the mass of the protein. PMID:23744064

  13. Synaptosome-Associated Protein 25 (SNAP25) Gene Association Analysis Revealed Risk Variants for ASD, in Iranian Population.

    PubMed

    Safari, Mohammad Reza; Omrani, Mir Davood; Noroozi, Rezvan; Sayad, Arezou; Sarrafzadeh, Shaghayegh; Komaki, Alireza; Manjili, Fateme Asadzadeh; Mazdeh, Mehrdokht; Ghaleiha, Ali; Taheri, Mohammad

    2017-03-01

    Autism spectrum disorder (ASD) is a common, complex neurological condition, affecting approximately 1% of people worldwide. Monogenic neurodevelopmental disorders which showed autistic behavior patterns have suggested synaptic dysfunction, as a key mechanism in the pathophysiology of ASD. Subsequently, genes involved in synaptic signaling have been investigated with a priority for candidate gene studies. A synaptosomal-associated protein 25 (SNAP25) gene plays a crucial role in the central nervous system, contributing to exocytosis by targeting and fusion of vesicles to the cell membrane. Studies have shown a correlation between aberrant expression of the SNAP25 and a variety of brain diseases. Single nucleotide polymorphisms (SNPs) in this gene are associated with several psychiatric diseases, such as bipolar, schizophrenia, and attention-deficit/hyperactivity disorder. The aim of the present study was to investigate whether polymorphisms (rs3746544 and rs1051312) in the regulatory 3'-untranslated region (3'UTR) of the SNAP25 gene have an association with ASD in unrelated Iranian case (N = 524)-control (N = 472) samples. We observed robust association of the rs3746544 SNP and ASD patients, in both allele and haplotype-based analyses. Our results supported the previous observations and indicated a possible role for SNAP25 polymorphisms as susceptibility genetic factors involved in developing ASD.

  14. Bacterial Heat Shock Protein GroEL (Hsp64) Exerts Immunoregulatory Effects on T Cells by Utilizing Apoptosis

    PubMed Central

    Nalbant, Ayten; Kant, Melis

    2016-01-01

    Aggregatibacter actinomycetemcomitans (Aa) expresses a 64-kDa GroEL protein belonging to the heat shock family of proteins. This protein has been shown to influence human host cells, but the apoptotic capacity of the GroEL protein regarding T cells is not yet known. The purpose of this study was to investigate the ability of A. actinomycetemcomitans GroEL (AaGroEL) protein to induce human peripheral blood T-cell apoptosis. Endogenous, purified AaGroEL protein was used as an antigen. In AaGroEL-treated T cells, the data indicated that phosphatidylserine exposure, an early apoptotic event, was dose- and time-dependent. The AaGroEL-treated T cells were also positive for active caspase-3 in a dose-dependent manner. The rate of AaGroEL-induced apoptosis was suppressed by the addition of the general caspase inhibitor Z-VAD-FMK. Furthermore, cleaved caspase-8 bands (40/36 kDa and 23 kDa) were identified in cells responding to AaGroEL. DNA fragmentation was also detected in the AaGroEL-treated T cells. Overall, we demonstrated that the endogenous GroEL from A. actinomycetemcomitans has the capacity to induce T-cell apoptosis. PMID:27736933

  15. Angiotensin I-Converting Enzyme (ACE) Inhibitory Activity, Antioxidant Properties, Phenolic Content and Amino Acid Profiles of Fucus spiralis L. Protein Hydrolysate Fractions

    PubMed Central

    Paiva, Lisete; Neto, Ana Isabel; Baptista, José

    2017-01-01

    Food protein-derived hydrolysates with multi-bioactivities such as antihypertensive and antioxidant properties have recently received special attention since both activities can play significant roles in preventing cardiovascular diseases. This study reports, for the first time, the angiotensin I-converting enzyme (ACE)-inhibition and antioxidant properties of ultrafiltrate fractions (UF) with different molecular weight ranges (<1, 1–3 and ≥3 kDa) obtained from Fucus spiralis protein hydrolysate (FSPH) digested with cellulase–bromelain. The amino acids profile, recovery yield, protein, peptide and total phenolic contents of these FSPH-UF, and the in vitro digestibility of F. spiralis crude protein were also investigated. FSPH-UF ≥3 kDa presented remarkably higher ACE-inhibition, yield, peptide and polyphenolic (phlorotannins) contents. Antioxidant analysis showed that FSPH-UF <1 kDa and ≥3 kDa exhibited significantly higher scavenging of 2,2-diphenyl-1-picrylhydrazyl radical and ferrous ion-chelating (FIC) activity. FSPH-UF ≥3 kDa had also notably higher ferric reducing antioxidant power (FRAP). Strong correlations were observed between ACE-inhibition and antioxidant activities (FIC and FRAP). The results suggest that ACE-inhibition and antioxidant properties of FSPH-UF may be due to the bioactive peptides and polyphenols released during the enzymatic hydrolysis. In conclusion, this study shows the potential use of defined size FSPH-UF for the prevention/treatment of hypertension and/or oxidative stress-related diseases. PMID:29027934

  16. A Robust Two-Dimensional Separation of Intact Proteins for Bottom-Up Tandem Mass Spectrometry of the Human CSF Proteome

    PubMed Central

    Bora, Adriana; Anderson, Carol; Bachani, Muznabanu; Nath, Avindra; Cotter, Robert J.

    2012-01-01

    The cerebrospinal fluid (CSF) is produced in the brain by cells in the choroid plexus at a rate of 500mL/day. It is the only body fluid in direct contact with the brain. Thus, any changes in the CSF composition will reflect pathological processes and make CSF a potential source of biomarkers for different disease states. Proteomics offers a comprehensive view of the proteins found in CSF. In this study, we use a recently developed non-gel based method of sample preparation of CSF followed by liquid chromatography high accuracy mass spectrometry (LC-MS) for MS and MS/MS analyses, allowing unambiguous identification of peptides/proteins. Gel-eluted liquid fraction entrapment electrophoresis (Gelfree) is used to separate a CSF complex protein mixture in 12 user-selectable liquid-phase molecular weight fractions. Using this high throughput workflow we have been able to separate CSF intact proteins over a broad mass range 3.5 kDa-100 kDa with high resolution between 15 kDa and 100 kDa in 2 hours and 40 min. We have completely eliminated albumin and were able to interrogate the low abundance CSF proteins in a highly reproducible manner from different CSF samples in the same time. Using LC-MS as a downstream analysis, we identified 368 proteins using MidiTrap G-10 desalting columns and 166 proteins (including 57 unique proteins) using Zeba spin columns with 5% false discovery rate (FDR). Prostaglandin D2 synthase, Chromogranin A, Apolipoprotein E, Chromogranin B, Secretogranin III, Cystatin C, VGF nerve growth factor, Cadherin 2 are a few of the proteins that were characterized. The Gelfree-LC-MS is a robust method for the analysis of the human proteome that we will use to develop biomarkers for several neurodegenerative diseases and to quantitate these markers using multiple reaction monitoring. PMID:22537003

  17. Effect of whey protein hydrolysates with different molecular weight on fatigue induced by swimming exercise in mice.

    PubMed

    Liu, Jing; Wang, Xinxia; Zhao, Zheng

    2014-01-15

    In order to improve the antioxidant and anti-fatigue capacities of whey protein for wider utilization, it was hydrolyzed by chymotrypsin (EC 3.4.21.1) to produce whey protein hydrolysate (WPH). Fractions of WPH with different molecular weight (MW) were separated by ultrafiltration. Kunming mice in various treatment groups were orally administered (1.5 g kg(-1) body weight) whey protein isolate (WPI), WPH or WPHs with different MW (<5, 5-10, 10-30 or >30 kDa) for 6 weeks to explore whether different MW fractions of WPH affected mice fatigue. Compared with the control group (orally administered 9 g kg(-1) saline) or the WPI group, low-MW (<10 kDa) WPH groups showed prolonged swimming time (P < 0.05) and had higher concentrations (P < 0.05) of glucose, non-esterfied fatty acid, liver glycogen, superoxide dismutase and glutathione peroxidase and lower concentration of lactate. Low-MW (<10 kDa) WPHs had higher hydroxyl- and α,α-diphenyl-β-picrylhydrazyl-scavenging abilities and ferrous-chelating capacity than WPI. The results proved that low-MW (<10 kDa) WPHs with higher anti-fatigue capacity showed higher free radical-scavenging and ferrous-chelating activities. © 2013 Society of Chemical Industry.

  18. Antibodies against recombinant heat shock proteins of 60 kDa from enterobacteria in the sera and synovial fluid of HLA-B27 positive ankylosing spondylitis patients.

    PubMed

    Domínguez-López, M L; Ortega-Ortega, Y; Manríquez-Raya, J C; Burgos-Vargas, R; Vega-López, A; García-Latorre, E

    2009-01-01

    To study the association of HLA-B27 with IgG antibodies to different enterobacterial HSP60s in patients with ankylosing spondylitis (AS). IgG antibodies to 60 kDa enterobacterial HSPs were determined by ELISA in paired samples of sera and synovial fluid from 21 HLA-B27+ ankylosing spondylitis (AS) patients; and in sera from 32 HLA-B27+ AS patients, 35 HLA-B27+ healthy relatives of AS patients, and 60 HLA-B27- healthy individuals with no family members with AS. HLA-B27+ patients and healthy individuals showed significantly higher IgG antibody levels to recombinant enterobacterial HSP60s than HLA-B27- healthy controls. The levels of anti-HSP60Sf and anti-HSP60Ec antibodies correlated with disease activity and anti-HSP60Ec antibodies with male gender. No association between enterobacterial HSP60 antibody levels and disease duration was observed. All groups had lower levels of IgG antibodies to rHSP60 from Streptococcus pyogenes (rHSP60 Spy). In paired samples of sera and synovial fluid from B27+ patients, IgG antibodies to enterobacterial HSP60s were detected, but in significantly higher levels in sera than in synovial fluid. The anti-rHSPSpy IgG response in these samples was lower and similar in the three groups. A correlation was found between HLA-B27 and the response to recombinat enterobacterial HSP60s. This response could be associated with disease activitir and gender in some proteins and the presence eof IgG antibodies to these proteins in synovial fluid could be associated with the inflammatory process and initiation of AS.

  19. Two novel heat shock genes encoding proteins produced in response to heterologous protein expression in Escherichia coli.

    PubMed Central

    Allen, S P; Polazzi, J O; Gierse, J K; Easton, A M

    1992-01-01

    In Escherichia coli high-level production of some heterologous proteins (specifically, human prorenin, renin, and bovine insulin-like growth factor 2) resulted in the induction of two new E. coli heat shock proteins, both of which have molecular masses of 16 kDa and are tightly associated with inclusion bodies formed during heterologous protein production. We named these inclusion body-associated proteins IbpA and IbpB. The coding sequences for IbpA and IbpB were identified and isolated from the Kohara E. coli gene bank. The genes for these proteins (ibpA and ibpB) are located at 82.5 min on the chromosome. Nucleotide sequencing of the two genes revealed that they are transcribed in the same direction and are separated by 110 bp. Putative Shine-Dalgarno sequences are located upstream from the initiation codons of both genes. A putative heat shock promoter is located upstream from ibpA, and a putative transcription terminator is located downstream from ibpB. A temperature upshift experiment in which we used a wild-type E. coli strain and an isogenic rpoH mutant strain indicated that a sigma 32-containing RNA polymerase is involved in the regulation of expression of these genes. There is 57.5% identity between the genes at the nucleotide level and 52.2% identity at the amino acid level. A search of the protein data bases showed that both of these 16-kDa proteins exhibit low levels of homology to low-molecular-weight heat shock proteins from eukaryotic species. Images PMID:1356969

  20. Structural and antigenic identification of the ORF12 protein (alpha TIF) of equine herpesvirus 1.

    PubMed

    Lewis, J B; Thompson, Y G; Feng, X; Holden, V R; O'Callaghan, D; Caughman, G B

    1997-04-14

    The equine herpesvirus 1 (EHV-1) homolog of the herpes simplex virus type 1 (HSV-1) tegument phosphoprotein, alpha TIF (Vmw65; VP16), was identified previously as the product of open reading frame 12 (ORF12) and shown to transactivate immediate early (IE) gene promoters. However, a specific virion protein corresponding to the ORF12 product has not been identified definitively. In the present study the ORF12 protein, designated ETIF, was identified as a 60-kDa virion component on the basis of protein fingerprint analyses in which the limited proteolysis profiles of the major 60-kDa in vitro transcription/ translation product of an ORF12 expression vector (pT7-12) were compared to those of purified virion proteins of similar size. ETIF was localized to the viral tegument in Western blot assays of EHV-1 virions and subvirion fractions using polyclonal antiserum and monoclonal antibodies generated against a glutathione-S-transferase-ETIF fusion protein. Northern and Western blot analyses of EHV-1-infected cell lysates prepared under various metabolic blocks indicated that ORF12 is expressed as a late gene, and cross reaction of polyclonal anti-GST-ETIF with a 63.5-kDa HSV-1 protein species suggested that ETIF and HSV-1 alpha TIF are antigenically related. Last, DNA band shift assays used to assess ETIF-specific complex formation indicated that ETIF participates in an infected cell protein complex with the EHV-1 IE promoter TAATGARAT motif.

  1. Purification and characterization of Campylobacter rectus surface layer proteins.

    PubMed Central

    Nitta, H; Holt, S C; Ebersole, J L

    1997-01-01

    Campylobacter rectus is a putative periodontopathogen which expresses a proteinaceous surface layer (S-layer) external to the outer membrane. S-layers are considered to play a protective role for the microorganism in hostile environments. The S-layer proteins from six different C. rectus strains (five human isolates and a nonhuman primate [NHP] isolate) were isolated, purified, and characterized. The S-layer proteins of these strains varied in molecular mass (ca. 150 to 166 kDa) as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. They all reacted with monospecific rabbit antiserum to the purified S-layer of C. rectus 314, but a quantitative enzyme-linked immunosorbent assay demonstrated a strong antigenic relationship among the five human strains, while the NHP strain, 6250, showed weaker reactivity. Amino acid composition analysis showed that the S-layers of four C. rectus strains contained large proportions of acidic amino acids (13 to 27%) and that >34% of the amino acid residues were hydrophobic. Amino acid sequence analysis of six S-layer proteins revealed that the first 15 amino-terminal amino acids were identical and showed seven residues of identity with the amino-terminal sequence of the Campylobacter fetus S-layer protein SapA1. CNBr peptide profiles of the S-layer proteins from C. rectus 314, ATCC 33238, and 6250 confirmed that the S-layer proteins from the human strains were similar to each other and somewhat different from that of the NHP isolate (strain 6250). However, the S-layer proteins from the two human isolates do show some structural heterogeneity. For example, there was a 17-kDa fragment unique to the C. rectus 314 S-layer. The amino-terminal sequence of this peptide had homology with the C. rectus 51-kDa porin and was composed of nearly 50% hydrophobic residues. Thus, the S-layer protein from C. rectus has structural heterogeneity among different human strains and immunoheterogeneity with the NHP strain. PMID:9009300

  2. MOLECULAR MECHANISM OF HUMAN NRF2 ACTIVATION AND DEGRADATION: ROLE OF SEQUENTIAL PHOSPHORYLATION BY PROTEIN KINASE CK2

    PubMed Central

    Pi, Jingbo; Bai, Yushi; Reece, Jeffrey M.; Williams, Jason; Liu, Dianxin; Freeman, Michael L.; Fahl, William E.; Shugar, David; Liu, Jie; Qu, Wei; Collins, Sheila; Waalkes, Michael P.

    2007-01-01

    Nrf2 is a key transcription factor in the cellular response to oxidative stress. In this study we first identify two phosphorylated forms of endogenous human Nrf2 after chemically-induced oxidative stress and provide evidence that protein kinase CK2-mediated sequential phosphorylation plays potential role in Nrf2 activation and degradation. Human Nrf2 has a predicted molecular mass of 66 kDa. However, immunoblots showed that two bands at 98 and 118 kDa, which are identified as phosphorylated forms, are increased in response to Nrf2 inducers. In addition, human Nrf2 was found to be a substrate for CK2 which mediated two steps of phosphorylation, resulting in two forms of Nrf2 migrating with differing Mr at 98 kDa (Nrf2–98) and 118 kDa (Nrf2–118). Our results support a role in which calmodulin binding regulates CK2 activity, in that cold (25 °C) in Ca2+-free media (cold/Ca2+-free) decreased both cellular calcium levels and CK2-calmodulin binding and induced Nrf2–118 formation, the latter of which was prevented by CK2 specific inhibitors. Gel-shift assays showed that the Nrf2–118 generated under cold/Ca2+-free conditions does not bind to the antioxidant response element, indicating that Nrf2–98 has transcriptional activity. In contrast, Nrf2–118 is more susceptible to degradation. These results provide evidence for phosphorylation by CK2 as a critical controlling factor in Nrf2-mediated cellular antioxidant response. PMID:17512459

  3. Structure of the large FK506-binding protein FKBP51, an Hsp90-binding protein and a component of steroid receptor complexes

    PubMed Central

    Sinars, Cindy R.; Cheung-Flynn, Joyce; Rimerman, Ronald A.; Scammell, Jonathan G.; Smith, David F.; Clardy, Jon

    2003-01-01

    The ability to bind immunosuppressive drugs such as cyclosporin and FK506 defines the immunophilin family of proteins, and the FK506-binding proteins form the FKBP subfamily of immunophilins. Some FKBPs, notably FKBP12 (the 12-kDa FK506-binding protein), have defined roles in regulating ion channels or cell signaling, and well established structures. Other FKBPs, especially the larger ones, participate in important biological processes, but their exact roles and the structural bases for these roles are poorly defined. FKBP51 (the 51-kDa FKBP) associates with heat shock protein 90 (Hsp90) and appears in functionally mature steroid receptor complexes. In New World monkeys, FKBP51 has been implicated in cortisol resistance. We report here the x-ray structures of human FKBP51, to 2.7 Å, and squirrel monkey FKBP51, to 2.8 Å, by using multiwavelength anomalous dispersion phasing. FKBP51 is composed of three domains: two consecutive FKBP domains and a three-unit repeat of the TPR (tetratricopeptide repeat) domain. This structure of a multi-FKBP domain protein clarifies the arrangement of these domains and their possible interactions with other proteins. The two FKBP domains differ by an insertion in the second that affects the formation of the progesterone receptor complex. PMID:12538866

  4. Gastrointestinal Endogenous Protein-Derived Bioactive Peptides: An in Vitro Study of Their Gut Modulatory Potential

    PubMed Central

    Dave, Lakshmi A.; Hayes, Maria; Mora, Leticia; Montoya, Carlos A.; Moughan, Paul J.; Rutherfurd, Shane M.

    2016-01-01

    A recently proposed paradigm suggests that, like their dietary counterparts, digestion of gastrointestinal endogenous proteins (GEP) may also produce bioactive peptides. With an aim to test this hypothesis, in vitro digests of four GEP namely; trypsin (TRYP), lysozyme (LYS), mucin (MUC), serum albumin (SA) and a dietary protein chicken albumin (CA) were screened for their angiotensin-I converting (ACE-I), renin, platelet-activating factor-acetylhydrolase (PAF-AH) and dipeptidyl peptidase-IV inhibitory (DPP-IV) and antioxidant potential following simulated in vitro gastrointestinal digestion. Further, the resultant small intestinal digests were enriched to obtain peptides between 3–10 kDa in size. All in vitro digests of the four GEP were found to inhibit ACE-I compared to the positive control captopril when assayed at a concentration of 1 mg/mL, while the LYS < 3-kDa permeate fraction inhibited renin by 40% (±1.79%). The LYS < 10-kDa fraction inhibited PAF-AH by 39% (±4.34%), and the SA < 3-kDa fraction inhibited DPP-IV by 45% (±1.24%). The MUC < 3-kDa fraction had an ABTS-inhibition antioxidant activity of 150 (±24.79) µM trolox equivalent and the LYS < 10-kDa fraction inhibited 2,2-Diphenyl-1-picrylhydrazyl (DPPH) by 54% (±1.62%). Moreover, over 190 peptide-sequences were identified from the bioactive GEP fractions. The findings of the present study indicate that GEP are a significant source of bioactive peptides which may influence gut function. PMID:27043546

  5. Electrospray-assisted laser desorption/ionization and tandem mass spectrometry of peptides and proteins.

    PubMed

    Peng, Ivory X; Shiea, Jentaie; Ogorzalek Loo, Rachel R; Loo, Joseph A

    2007-01-01

    We have constructed an electrospray-assisted laser desorption/ionization (ELDI) source which utilizes a nitrogen laser pulse to desorb intact molecules from matrix-containing sample solution droplets, followed by electrospray ionization (ESI) post-ionization. The ELDI source is coupled to a quadrupole ion trap mass spectrometer and allows sampling under ambient conditions. Preliminary data showed that ELDI produces ESI-like multiply charged peptides and proteins up to 29 kDa carbonic anhydrase and 66 kDa bovine albumin from single-protein solutions, as well as from complex digest mixtures. The generated multiply charged polypeptides enable efficient tandem mass spectrometric (MS/MS)-based peptide sequencing. ELDI-MS/MS of protein digests and small intact proteins was performed both by collisionally activated dissociation (CAD) and by nozzle-skimmer dissociation (NSD). ELDI-MS/MS may be a useful tool for protein sequencing analysis and top-down proteomics study, and may complement matrix-assisted laser desorption/ionization (MALDI)-based measurements. Copyright (c) 2007 John Wiley & Sons, Ltd.

  6. Mapping and isolation of the pulmonary veins using the PVAC catheter.

    PubMed

    Duytschaever, Mattias; Anne, Wim; Papiashvili, Giorgi; Vandekerckhove, Yves; Tavernier, Rene

    2010-02-01

    We aimed to investigate the feasibility, efficacy, and safety of the pulmonary vein ablation catheter (PVAC) catheter (a novel multielectrode catheter using duty-cycled bipolar and unipolar radiofrequency energy, Medtronic, Minneapolis, MN, USA) to completely isolate the pulmonary veins (PVs). Twenty-seven patients (60 +/- 8 years) with paroxysmal atrial fibrillation (AF) underwent PV isolation with the PVAC catheter. PVAC was used for both mapping and isolation of the PVs (PVAC-guided ablation). After PVAC ablation, presence/absence of PV potentials (PVP) was verified using a conventional circular mapping catheter. In case of residual PVP on the circular catheter, PVAC ablation was continued. After PVAC-guided ablation 99 of 106 PVs (93%) and 21 of 27 patients (78%) were proven to be isolated. Failure to isolate was due to a mapping failure in four right-sided PVs and a true ablation failure in three right-sided PVs. After continued PVAC ablation, 103 of 106 PVs (97%) and 25 of 27 patients (93%) were shown to be isolated. The total procedural time from femoral vein access to complete catheter withdrawal was 176 +/- 25 minutes. The actual dwelling-time of the PVAC within the left atrium was 102 +/- 37 minutes. Esophageal T degrees rise to >38.5 degrees occurred in nine of 19 monitored patients (47%). (1) PVAC-guided ablation (i.e., mapping and ablation with a single catheter) results in isolation of all PVs in 73% of the patients. (2) An additional circular mapping catheter is required to increase complete isolation rate to 93% of the patients. (3) Given the esophageal T degrees rise in almost 50% of patients, safety precautions are needed.

  7. A tyrosine-phosphorylated 55-kilodalton motility-associated bovine sperm protein is regulated by cyclic adenosine 3',5'-monophosphates and calcium.

    PubMed

    Vijayaraghavan, S; Trautman, K D; Goueli, S A; Carr, D W

    1997-06-01

    Sperm motility is regulated by protein phosphorylation. We have recently shown that a serine/threonine phosphatase system is involved in motility regulation. Two of the components of the phosphatase system, GSK-3 and PP1gamma2, are regulated by tyrosine phosphorylation. During our investigation of sperm tyrosine-phosphorylated proteins we discovered a 55-kDa protein whose tyrosine phosphorylation correlates closely to the motility state of sperm. This protein is tyrosine phosphorylated to a much higher degree in motile caudal than in immotile caput epididymal sperm. Motility inhibition of caudal epididymal sperm by protein kinase A (PKA) anchoring inhibition or by ionomycin-induced calcium overload led to the virtual disappearance of tyrosine phosphorylation of the 55-kDa protein. Conversely, treatment of sperm with motility activators, isobutylmethylxanthine or 8-bromo-cAMP, resulted in increased tyrosine phosphorylation of the protein. The protein was present in the soluble 100 000 x g supernatants of sperm extracts and was heat labile. Chromatography through diethylaminoethyl-cellulose and Western blot analysis showed that this 55-kDa protein is not a regulatory subunit of PKA or alpha-tubulin. Our results represent the identification of a soluble protein whose tyrosine phosphorylation varies directly with motility and suggest that motility regulation may involve cross talk between PKA, calcium, and tyrosine kinase pathways.

  8. Impairment of fragile X mental retardation protein-metabotropic glutamate receptor 5 signaling and its downstream cognates ras-related C3 botulinum toxin substrate 1, amyloid beta A4 precursor protein, striatal-enriched protein tyrosine phosphatase, and homer 1, in autism: a postmortem study in cerebellar vermis and superior frontal cortex

    PubMed Central

    2013-01-01

    Background Candidate genes associated with idiopathic forms of autism overlap with other disorders including fragile X syndrome. Our laboratory has previously shown reduction in fragile X mental retardation protein (FMRP) and increase in metabotropic glutamate receptor 5 (mGluR5) in cerebellar vermis and superior frontal cortex (BA9) of individuals with autism. Methods In the current study we have investigated expression of four targets of FMRP and mGluR5 signaling - homer 1, amyloid beta A4 precursor protein (APP), ras-related C3 botulinum toxin substrate 1 (RAC1), and striatal-enriched protein tyrosine phosphatase (STEP) - in the cerebellar vermis and superior frontal cortex (BA9) via SDS-PAGE and western blotting. Data were analyzed based on stratification with respect to age (children and adolescents vs. adults), anatomic region of the brain (BA9 vs. cerebellar vermis), and impact of medications (children and adolescents on medications (n = 4) vs. total children and adolescents (n = 12); adults on medications (n = 6) vs. total adults (n = 12)). Results There were significant increases in RAC1, APP 120 kDa and APP 80 kDa proteins in BA9 of children with autism vs. healthy controls. None of the same proteins were significantly affected in cerebellar vermis of children with autism. In BA9 of adults with autism there were significant increases in RAC1 and STEP 46 kDa and a significant decrease in homer 1 vs. controls. In the vermis of adult subjects with autism, RAC1 was significantly increased while APP 120, STEP 66 kDa, STEP 27 kDa, and homer 1 were significantly decreased when compared with healthy controls. No changes were observed in vermis of children with autism. There was a significant effect of anticonvulsant use on STEP 46 kDa/β-actin and a potential effect on homer 1/NSE, in BA9 of adults with autism. However, no other significant confound effects were observed in this study. Conclusions Our findings provide further evidence of abnormalities in FMRP and

  9. Extremely stable soluble high molecular mass multi-protein complex with DNase activity in human placental tissue.

    PubMed

    Burkova, Evgeniya E; Dmitrenok, Pavel S; Sedykh, Sergey E; Buneva, Valentina N; Soboleva, Svetlana E; Nevinsky, Georgy A

    2014-01-01

    Human placenta is an organ which protects, feeds, and regulates the grooving of the embryo. Therefore, identification and characterization of placental components including proteins and their multi-protein complexes is an important step to understanding the placenta function. We have obtained and analyzed for the first time an extremely stable multi-protein complex (SPC, ∼ 1000 kDa) from the soluble fraction of three human placentas. By gel filtration on Sepharose-4B, the SPC was well separated from other proteins of the placenta extract. Light scattering measurements and gel filtration showed that the SPC is stable in the presence of NaCl, MgCl2, acetonitrile, guanidinium chloride, and Triton in high concentrations, but dissociates efficiently in the presence of 8 M urea, 50 mM EDTA, and 0.5 M NaCl. Such a stable complex is unlikely to be a casual associate of different proteins. According to SDS-PAGE and MALDI mass spectrometry data, this complex contains many major glycosylated proteins with low and moderate molecular masses (MMs) 4-14 kDa and several moderately abundant (79.3, 68.5, 52.8, and 27.2 kDa) as well as minor proteins with higher MMs. The SPC treatment with dithiothreitol led to a disappearance of some protein bands and revealed proteins with lower MMs. The SPCs from three placentas efficiently hydrolyzed plasmid supercoiled DNA with comparable rates and possess at least two DNA-binding sites with different affinities for a 12-mer oligonucleotide. Progress in study of placental protein complexes can promote understanding of their biological functions.

  10. Two Disease-Causing SNAP-25B Mutations Selectively Impair SNARE C-terminal Assembly.

    PubMed

    Rebane, Aleksander A; Wang, Bigeng; Ma, Lu; Qu, Hong; Coleman, Jeff; Krishnakumar, Shyam; Rothman, James E; Zhang, Yongli

    2018-02-16

    Synaptic exocytosis relies on assembly of three soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) proteins into a parallel four-helix bundle to drive membrane fusion. SNARE assembly occurs by stepwise zippering of the vesicle-associated SNARE (v-SNARE) onto a binary SNARE complex on the target plasma membrane (t-SNARE). Zippering begins with slow N-terminal association followed by rapid C-terminal zippering, which serves as a power stroke to drive membrane fusion. SNARE mutations have been associated with numerous diseases, especially neurological disorders. It remains unclear how these mutations affect SNARE zippering, partly due to difficulties to quantify the energetics and kinetics of SNARE assembly. Here, we used single-molecule optical tweezers to measure the assembly energy and kinetics of SNARE complexes containing single mutations I67T/N in neuronal SNARE synaptosomal-associated protein of 25kDa (SNAP-25B), which disrupt neurotransmitter release and have been implicated in neurological disorders. We found that both mutations significantly reduced the energy of C-terminal zippering by ~10 k B T, but did not affect N-terminal assembly. In addition, we observed that both mutations lead to unfolding of the C-terminal region in the t-SNARE complex. Our findings suggest that both SNAP-25B mutations impair synaptic exocytosis by destabilizing SNARE assembly, rather than stabilizing SNARE assembly as previously proposed. Therefore, our measurements provide insights into the molecular mechanism of the disease caused by SNARE mutations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Chemical shift changes provide evidence for overlapping single-stranded DNA- and XPA-binding sites on the 70 kDa subunit of human replication protein A.

    PubMed

    Daughdrill, Gary W; Buchko, Garry W; Botuyan, Maria V; Arrowsmith, Cheryl; Wold, Marc S; Kennedy, Michael A; Lowry, David F

    2003-07-15

    Replication protein A (RPA) is a heterotrimeric single-stranded DNA- (ssDNA) binding protein that can form a complex with the xeroderma pigmentosum group A protein (XPA). This complex can preferentially recognize UV-damaged DNA over undamaged DNA and has been implicated in the stabilization of open complex formation during nucleotide excision repair. In this report, nuclear magnetic resonance (NMR) spectroscopy was used to investigate the interaction between a fragment of the 70 kDa subunit of human RPA, residues 1-326 (hRPA70(1-326)), and a fragment of the human XPA protein, residues 98-219 (XPA-MBD). Intensity changes were observed for amide resonances in the (1)H-(15)N correlation spectrum of uniformly (15)N-labeled hRPA70(1-326) after the addition of unlabeled XPA-MBD. The intensity changes observed were restricted to an ssDNA-binding domain that is between residues 183 and 296 of the hRPA70(1-326) fragment. The hRPA70(1-326) residues with the largest resonance intensity reductions were mapped onto the structure of the ssDNA-binding domain to identify the binding surface with XPA-MBD. The XPA-MBD-binding surface showed significant overlap with an ssDNA-binding surface that was previously identified using NMR spectroscopy and X-ray crystallography. Overlapping XPA-MBD- and ssDNA-binding sites on hRPA70(1-326) suggests that a competitive binding mechanism mediates the formation of the RPA-XPA complex. To determine whether a ternary complex could form between hRPA70(1-326), XPA-MBD and ssDNA, a (1)H-(15)N correlation spectrum was acquired for uniformly (15)N-labeled hRPA70(1-326) after the simultaneous addition of unlabeled XPA-MBD and ssDNA. In this experiment, the same chemical shift perturbations were observed for hRPA70(1-326) in the presence of XPA-MBD and ssDNA as was previously observed in the presence of ssDNA alone. The ability of ssDNA to compete with XPA-MBD for an overlapping binding site on hRPA70(1-326) suggests that any complex formation between RPA

  12. Chemical shift changes provide evidence for overlapping single-stranded DNA- and XPA-binding sites on the 70 kDa subunit of human replication protein A

    PubMed Central

    Daughdrill, Gary W.; Buchko, Garry W.; Botuyan, Maria V.; Arrowsmith, Cheryl; Wold, Marc S.; Kennedy, Michael A.; Lowry, David F.

    2003-01-01

    Replication protein A (RPA) is a heterotrimeric single-stranded DNA- (ssDNA) binding protein that can form a complex with the xeroderma pigmentosum group A protein (XPA). This complex can preferentially recognize UV-damaged DNA over undamaged DNA and has been implicated in the stabilization of open complex formation during nucleotide excision repair. In this report, nuclear magnetic resonance (NMR) spectroscopy was used to investigate the interaction between a fragment of the 70 kDa subunit of human RPA, residues 1–326 (hRPA701–326), and a fragment of the human XPA protein, residues 98–219 (XPA-MBD). Intensity changes were observed for amide resonances in the 1H–15N correlation spectrum of uniformly 15N-labeled hRPA701–326 after the addition of unlabeled XPA-MBD. The intensity changes observed were restricted to an ssDNA-binding domain that is between residues 183 and 296 of the hRPA701–326 fragment. The hRPA701–326 residues with the largest resonance intensity reductions were mapped onto the structure of the ssDNA-binding domain to identify the binding surface with XPA-MBD. The XPA-MBD-binding surface showed significant overlap with an ssDNA-binding surface that was previously identified using NMR spectroscopy and X-ray crystallography. Overlapping XPA-MBD- and ssDNA-binding sites on hRPA701–326 suggests that a competitive binding mechanism mediates the formation of the RPA–XPA complex. To determine whether a ternary complex could form between hRPA701–326, XPA-MBD and ssDNA, a 1H–15N correlation spectrum was acquired for uniformly 15N-labeled hRPA701–326 after the simultaneous addition of unlabeled XPA-MBD and ssDNA. In this experiment, the same chemical shift perturbations were observed for hRPA701–326 in the presence of XPA-MBD and ssDNA as was previously observed in the presence of ssDNA alone. The ability of ssDNA to compete with XPA-MBD for an overlapping binding site on hRPA701–326 suggests that any complex formation between RPA

  13. JAK1 kinase forms complexes with interleukin-4 receptor and 4PS/insulin receptor substrate-1-like protein and is activated by interleukin-4 and interleukin-9 in T lymphocytes.

    PubMed

    Yin, T; Tsang, M L; Yang, Y C

    1994-10-28

    Interleukin (IL)-4 and IL-9 regulate the proliferation of T lymphocytes through interactions with their receptors. Previous studies have shown that unknown tyrosine kinases are involved in the proliferative signaling triggered by IL-4 and IL-9. Here we show that IL-4 and IL-9 induce overlapping (170, 130, and 125 kilodalton (kDa)) and distinct (45 and 88/90 kDa, respectively) protein tyrosine phosphorylation in T lymphocytes. We further identify the 170-kDa tyrosine-phosphorylated protein as 4PS/insulin receptor substrate-1-like (IRS-1L) protein and 130-kDa protein as JAK1 kinase. Furthermore, we demonstrate for the first time that JAK1 forms complexes with the IL-4 receptor and 4PS/IRS-1L protein following ligand-receptor interaction. In addition, we demonstrate that IL-9, but not IL-4, induced tyrosine phosphorylation of Stat 91 transcriptional factor. The overlapping and distinct protein tyrosine phosphorylation and activation of the same JAK1 kinase in T lymphocytes strongly suggests that IL-4 and IL-9 share the common signal transduction pathways and that the specificity for each cytokine could be achieved through the unique tyrosine-phosphorylated proteins triggered by individual cytokines.

  14. A Proteomic Approach to Characterize Protein Shedding

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ahram, Mamoun; Adkins, Joshua N.; Auberry, Deanna L.

    2005-01-01

    Shedding (i.e., proteolysis of ectodomains of membrane proteins) plays an important pathophysiological role. In order to study the feasibility of identifying shed proteins, we analyzed serum-free media of human mammary epithelial cells by mass spectrometry following induction of shedding by the phorbol ester, 4β-phorbol 12-myristate 13-acetate (PMA). Different means of sample preparation, including biotinylation of cell surface proteins, isolation of glycosylated proteins, and preparation of crude protein fraction, were carried out to develop the optimal method of sample processing. The collected proteins were digested with trypsin and analyzed by reversed-phase capillary liquid chromatography interfaced to an ion-trap mass spectrometer. Themore » resulting peptide spectra were interpreted using the program SEQUEST. Analyzing the sample containing the crude protein mixture without chemical modification or separation resulted in the greatest number of identifications, including putatively shed proteins. Overall, 93 membrane-associated proteins were identified including 57 that contain at least one transmembrane domain and 36 that indirectly associate with the extracellular surface of the plasma membrane. Of the 57 transmembrane proteins, 43 were identified by extracellular peptides providing strong evidence for them originating from regulated proteolysis or shedding processes. We combined results from the different experiments and used a peptide count method to estimate changes in protein abundance. Using this approach, we identified 2 proteins, syndecan-4 and hepatoma-derived growth factor, whose abundances increased in media of cells treated with PMA. We also detected proteins whose abundances decreased after PMA treatment such as 78-kDa glucose-regulated protein and calreticulin. Further analysis using immunoblotting validated the abundance changes for syndecan-4 and 78-kDa glucose-regulated protein as a result of PMA treatment. These results demonstrate that

  15. The potency of STAT (signal transducers and activators of transcription) 3 protein as growth promoter for chicken

    NASA Astrophysics Data System (ADS)

    Ma'ruf, Anwar; Iswati, Sri; Hidajati, Nove; Damayanti, Ratna

    2017-09-01

    The long-term objective of this study was to produce STAT synthetic protein in chicken during growth period resulting from the increase of growth hormone (GH) as growth promoter. This study used ten male chicken Lohman from PT. Multibreeder Indonesia. The chicken were kept within batteried cage, with a capacity of one chicken in each cage. The chickens were fed twice a day, at 6 a.m. and 6 p.m. with the amount of feed 10% less than standard. On day 21 the chicken were slaughtered to obtain the samples, i.e., adipose, liver and muscles for the following examinations (1) isolation of STAT-3 signaling protein from adipose, liver and muscles of the chicken, (2) analysis of STAT-3 signaling protein using SDS-PAGE method, and (3) identification of STAT-3 signaling protein using Western blot method by means of protein detection using electrophoresis with polyacrylamide gels. Results of examination on protein in hepatic, muscle and adipose of chickens in growth period revealed that STAT protein was positively present in those tissues. This finding was followed-up with SDS-PAGE examination, from which we found the presence of protein band between the markers of 116 kDa and 14.4 kDa. The protein band was supposedly the STAT-3 protein. To prove that protein band formed was the STAT-3, Western blot examination was conducted using rabbit polyclonal antibody STAT-3. The result showed the formation of the protein band, indicating the presence of reaction between antigen (STAT-3 protein) and STAT-3 protein antibody. In conclusion, STAT-3 protein is present in hepatic, muscular, and adipose tissues, with molecular weight of 59.4 kDa.

  16. The hypolipidemic effect and antithrombotic activity of Mucuna pruriens protein hydrolysates.

    PubMed

    Herrera Chalé, Francisco; Ruiz Ruiz, Jorge Carlos; Betancur Ancona, David; Acevedo Fernández, Juan José; Segura Campos, Maira Rubi

    2016-01-01

    Hydrolysates and peptide fractions (PF) obtained from M. pruriens protein concentrates with commercial and digestive enzymatic systems were studied for their hypolipidemic and antithrombotic activities. Hydrolysates obtained with Pepsin-Pancreatin (PP) and their peptide fractions inhibited cholesterol micellar solubility with a maximum value of 1.83% in PP. Wistar rats were used to evaluate the hypolipidemic effect of hydrolysates and PF. The higher reductions of cholesterol and triglyceride levels were exhibited by PP and both peptide fractions <1 kDa obtained from PP and Alcalase®-Flavourzyme® hydrolysate (AF) at a dose of 15 mg kg(-1) of animal weight. PF > 10 kDa from both hydrolysates showed the maximum antithrombotic activity with values of 33.33% for PF > 10 kDa from AF and 31.72% for PF > 10 kDa from PP. The results suggest that M. pruriens bioactive peptides with the hypolipidemic effect and antithrombotic activity might be utilized as nutraceuticals.

  17. Lipids and proteins in the Rathke's gland secretions of the North American mud turtle (Kinosternon subrubrum)

    USGS Publications Warehouse

    Seifert, W.E.; Gotte, S.W.; Leto, T.L.; Weldon, P.J.

    1994-01-01

    Lipids and proteins in the Rathke's gland secretions of the North American mud turtle (Kinosternon subrubrum, Kinosternidae) were analyzed by gas chromatography-mass spectrometry (GC-MS) and SDS-polyacrylamide gel electrophoresis (SDS-PAGE), respectively. Analysis by GC-MS indicates 2,3-dihydroxypropanal and C3–C24 free or esterified fatty acids. Analysis by SDS-PAGE indicates a major protein component with an approximate molecular mass of 60 kDa and minor components ranging from ca. 23 to 34 kDa. The major component of K. subrubrum glandular secretions exhibits a mobility that matches that of the Kemp's ridley sea turtle (Lepidochelys kempi, Cheloniidae), suggesting that these proteins are evolutionarily conserved.

  18. Protein expression of targets of the FMRP regulon is altered in brains of subjects with schizophrenia and mood disorders

    PubMed Central

    Folsom, Timothy D.; Thuras, Paul D.; Fatemi, S. Hossein

    2016-01-01

    Fragile X mental retardation protein (FMRP) is an RNA binding protein with 842 target mRNAs in mammalian brain. Silencing of the fragile X mental retardation 1 (FMR1) gene leads to loss of expression of FMRP and upregulated metabotropic glutamate receptor 5 (mGluR5) signaling resulting in the multiple physical and cognitive deficits associated with fragile X syndrome (FXS). Reduced FMRP expression has been identified in subjects with autism, schizophrenia, bipolar disorder, and major depression who do not carry the mutation for FMR1. Our laboratory has recently demonstrated altered expression of four downstream targets of FMRP-mGluR5 signaling in brains of subjects with autism: homer 1, amyloid beta A4 precursor protein (APP), ras-related C3 botulinum toxin substrate 1 (RAC1), and striatal-enriched protein tyrosine phosphatase (STEP). In the current study we investigated the expression of the same four proteins in lateral cerebella of subjects with schizophrenia, bipolar disorder, and major depression and in frontal cortex of subjects with schizophrenia and bipolar disorder. In frontal cortex we observed: 1) reduced expression of 120 kDa form of APP in subjects with schizophrenia and bipolar disorder; 2) reduced expression of 61 kDa and 33 kDa forms of STEP in subjects with schizophrenia; 3) reduced expression of 88 kDa form of APP in subjects with bipolar disorder; and 3) trends for reduced expression of 88 kDa form of APP and homer 1 in subjects with schizophrenia and bipolar disorder, respectively. In lateral cerebella there was no group difference, however we observed increased expression of RAC1 in subjects with bipolar disorder, and trends for increased RAC1 in subjects with schizophrenia and major depression. Our results provide further evidence that proteins involved in the FMRP-mGluR5 signaling pathway are altered in schizophrenia and mood disorders. PMID:25956630

  19. Carbene footprinting accurately maps binding sites in protein-ligand and protein-protein interactions

    NASA Astrophysics Data System (ADS)

    Manzi, Lucio; Barrow, Andrew S.; Scott, Daniel; Layfield, Robert; Wright, Timothy G.; Moses, John E.; Oldham, Neil J.

    2016-11-01

    Specific interactions between proteins and their binding partners are fundamental to life processes. The ability to detect protein complexes, and map their sites of binding, is crucial to understanding basic biology at the molecular level. Methods that employ sensitive analytical techniques such as mass spectrometry have the potential to provide valuable insights with very little material and on short time scales. Here we present a differential protein footprinting technique employing an efficient photo-activated probe for use with mass spectrometry. Using this methodology the location of a carbohydrate substrate was accurately mapped to the binding cleft of lysozyme, and in a more complex example, the interactions between a 100 kDa, multi-domain deubiquitinating enzyme, USP5 and a diubiquitin substrate were located to different functional domains. The much improved properties of this probe make carbene footprinting a viable method for rapid and accurate identification of protein binding sites utilizing benign, near-UV photoactivation.

  20. Analysis of bax protein in sphingosine-induced apoptosis in the human leukemic cell line TF1 and its bcl-2 transfectants.

    PubMed

    Isogai, C; Murate, T; Tamiya-Koizumi, K; Yoshida, S; Ito, T; Nagai, H; Kinoshita, T; Kagami, Y; Hotta, T; Hamaguchi, M; Saito, H

    1998-11-01

    Sphingosine, a sphingolipid breakdown product, has been proposed as an apoptosis-inducing agent. In this study, we examined the effect of sphingosine in bcl-2-overexpressing cells compared with cells that do not express the bcl-2 gene. The human erythroleukemic cell line TF1, which lacks bcl-2 expression, was easily induced to undergo apoptotic cell death by a variety of stimuli, including depletion of granulocyte-macrophage colony-stimulating factor (GM-CSF) or exposure to methylmethane sulfonate (MMS) (100 microg/mL), ultraviolet light (15 J/m2), X-ray irradiation (20 Gy), or sphingosine, a sphingolipid breakdown product (5 microM). In contrast, bcl-2 transfectants of TF1 (TF1-bcl2), which we established, were resistant to most of these treatments but remained sensitive to sphingosine. Neither C2- nor C6-ceramide (short-chain ceramide) induced apoptosis in TF1-mock and TF1-bcl2 cells. Sphingosine-induced apoptosis could not be inhibited by fumonisin B1, which can prevent conversion of sphingosine to ceramide, suggesting that sphingosine itself, not ceramide, possesses apoptosis-inducing capability. Western blotting, which revealed a 21-kDa bax protein in untreated cells, revealed the presence of an additional 18-kDa protein in GM-CSF-depleted and MMS- or sphingosine-treated TF1-mock cells. In TF1-bcl2 cells, this protein was not detected after GM-CSF depletion or MMS treatment, but was observed after sphingosine treatment. Immunoprecipitation with anti-bcl2 antibody, followed by immunoblotting with anti-bax antibody, showed that both the 21-kDa bax protein and the 18-kDa protein heterodimerized with bcl-2 protein. These results suggest that sphingosine is a unique reagent for apoptosis and that it can overcome bcl-2 gene expression. Furthermore, induction of 18-kDa bax-related protein may play an important role in apoptosis. Sphingosine, but not ceramide, may prove applicable as a reagent for future cytotoxic drugs used to treat intractable tumors overexpressing