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1

Biochemical differentiation of mycelium and yeast forms of Paracoccidioides brasiliensis by Fourier transform infrared spectroscopy  

NASA Astrophysics Data System (ADS)

Paracoccidioides brasiliensis the etiological agent of paracoccidioidomycosis, is a dimorphic fungus existing as mycelia in the environment (or at 25 °C in vitro) and as yeast cells in the human host (or at 37°C in vitro). The most prominent difference between both forms is probably the cell wall polysaccharide, being 1,3-?-glucan usually found in mycelia and 1,3-?-glucan found in yeasts, but a plethora of other differences have already been described. In this work, we performed a Fourier Transform Infrared Spectroscopy analysis to compare the yeast and mycelia forms of P. brasiliensis and found additional biochemical differences. The analysis of the spectra showed that differences were distributed in chemical bonds of proteins, lipids and carbohydrates.

Castilho, Maiara L.; Campos, Claudia B. L.; Matos, Tatiana G. F.; de Abreu, Geraldo M. A.; Martin, Airton A.; Raniero, Leandro

2012-01-01

2

Preparation of species-specific murine monoclonal antibodies against the yeast phase of Paracoccidioides brasiliensis.  

PubMed Central

A panel of four murine monoclonal antibodies showing species specificity for the yeast phase of the pathogenic dimorphic fungus Paracoccidioides brasiliensis was produced by using a modification of the standard monoclonal antibody technology. This involved the use of the immunosuppressive drug cyclophosphamide to suppress the immune response of test animals to fungi showing cross-reactivity, i.e., to Histoplasma capsulatum. One monoclonal antibody, P4, which had a high titer by enzyme-linked immunosorbent assay, was shown to recognize a linear antigenic epitope of P. brasiliensis at a molecular size of 70,000 to 75,000 daltons by Western blot (immunoblot) analysis. The potential use of these monoclonal antibodies, which are the first species-specific probes to P. brasiliensis that have been produced, in the field of serodiagnosis is discussed. Images PMID:2394802

Figueroa, J I; Hamilton, A J; Bartholomew, M A; Harada, T; Fenelon, L; Hay, R J

1990-01-01

3

Transcriptome Analysis of Paracoccidioides brasiliensis Cells Undergoing Mycelium-to-Yeast Transition  

PubMed Central

Paracoccidioides brasiliensis is a thermodimorphic fungus associated with paracoccidioidomycosis (PCM), a systemic mycosis prevalent in South America. In humans, infection starts by inhalation of fungal propagules, which reach the pulmonary epithelium and transform into the yeast parasitic form. Thus, the mycelium-to-yeast transition is of particular interest because conversion to yeast is essential for infection. We have used a P. brasiliensis biochip carrying sequences of 4,692 genes from this fungus to monitor gene expression at several time points of the mycelium-to-yeast morphological shift (from 5 to 120 h). The results revealed a total of 2,583 genes that displayed statistically significant modulation in at least one experimental time point. Among the identified gene homologues, some encoded enzymes involved in amino acid catabolism, signal transduction, protein synthesis, cell wall metabolism, genome structure, oxidative stress response, growth control, and development. The expression pattern of 20 genes was independently verified by real-time reverse transcription-PCR, revealing a high degree of correlation between the data obtained with the two methodologies. One gene, encoding 4-hydroxyl-phenyl pyruvate dioxygenase (4-HPPD), was highly overexpressed during the mycelium-to-yeast differentiation, and the use of NTBC [2-(2-nitro-4-trifluoromethylbenzoyl)-cyclohexane-1,3-dione], a specific inhibitor of 4-HPPD activity, as well as that of NTBC derivatives, was able to inhibit growth and differentiation of the pathogenic yeast phase of the fungus in vitro. These data set the stage for further studies involving NTBC and its derivatives as new chemotherapeutic agents against PCM and confirm the potential of array-based approaches to identify new targets for the development of alternative treatments against pathogenic microorganisms. PMID:16339729

Nunes, Luiz R.; Costa de Oliveira, Regina; Leite, Daniela Batista; da Silva, Vivian Schmidt; dos Reis Marques, Everaldo; da Silva Ferreira, Márcia Eliana; Ribeiro, Diógenes Custódio Duarte; de Souza Bernardes, Luciano Ângelo; Goldman, Maria Helena S.; Puccia, Rosana; Travassos, Luiz R.; Batista, Wagner L.; Nóbrega, Marina Pasetto; Nobrega, Francisco G.; Yang, Ding-Yah; de Bragança Pereira, Carlos A.; Goldman, Gustavo H.

2005-01-01

4

Comparison of transcription of multiple genes during mycelia transition to yeast cells of Paracoccidioides brasiliensis reveals insights to fungal differentiation and pathogenesis  

Microsoft Academic Search

The ascomycete Paracoccidioides brasiliensis is a human pathogen with a broad distribution in Latin America. The infection process of P. brasiliensis is initiated by aerially dispersed mycelia propagules, which differentiate into the yeast parasitic phase in human lungs.\\u000a Therefore, the transition to yeast is an initial and fundamental step in the infective process. In order to identify and characterize\\u000a genes

Juliana Alves Parente; Clayton Luiz Borges; Alexandre Melo Bailão; Maria Sueli S. Felipe; Maristela Pereira; Célia Maria de Almeida Soares

2008-01-01

5

Evidence for the role of calcineurin in morphogenesis and calcium homeostasis during mycelium-to-yeast dimorphism of Paracoccidioides brasiliensis.  

PubMed

Paracoccidioides brasiliensis is a dimorphic fungus that causes paracoccidioidomycosis, the most prevalent human deep mycosis in Latin America. The dimorphic transition from mycelium to yeast (M-Y) is triggered by a temperature shift from 25 degrees C to 37 degrees C and is critical for pathogenicity. Intracellular Ca(2+) levels increased in hyphae immediately after temperature-induced dimorphism. The chelation of Ca(2+) with extracellular (EGTA) or intracellular (BAPTA) calcium chelators inhibited temperature-induced dimorphism, whereas the addition of extracellular Ca(2+) accelerated dimorphism. The calcineurin inhibitor cyclosporine A (CsA), but not tacrolimus (FK506), effectively decreased cell growth, halted the M-Y transition that is associated with virulence, and caused aberrant growth morphologies for all forms of P. brasiliensis. The difference between CsA and FK506 was ascribed by the higher levels of cyclophilins contrasted to FKBPs, the intracellular drug targets required for calcineurin suppression. Chronic exposure to CsA abolished intracellular Ca(2+) homeostasis and decreased mRNA transcription of the CCH1 gene for the plasma membrane Ca(2+) channel in yeast-form cells. CsA had no detectable effect on multidrug resistance efflux pumps, while the effect of FK506 on rhodamine excretion was not correlated with the transition to yeast form. In this study, we present evidence that Ca(2+)/calmodulin-dependent phosphatase calcineurin controls hyphal and yeast morphology, M-Y dimorphism, growth, and Ca(2+) homeostasis in P. brasiliensis and that CsA is an effective chemical block for thermodimorphism in this organism. The effects of calcineurin inhibitors on P. brasiliensis reinforce the therapeutic potential of these drugs in a combinatory approach with antifungal drugs to treat endemic paracoccidioidomycosis. PMID:18776037

Campos, Claudia B L; Di Benedette, Joao Paulo T; Morais, Flavia V; Ovalle, Rafael; Nobrega, Marina P

2008-10-01

6

Involvement of an Alternative Oxidase in Oxidative Stress and Mycelium-to-Yeast Differentiation in Paracoccidioides brasiliensis ? †  

PubMed Central

Paracoccidioides brasiliensis is a thermodimorphic human pathogenic fungus that causes paracoccidioidomycosis (PCM), which is the most prevalent systemic mycosis in Latin America. Differentiation from the mycelial to the yeast form (M-to-Y) is an essential step for the establishment of PCM. We evaluated the involvement of mitochondria and intracellular oxidative stress in M-to-Y differentiation. M-to-Y transition was delayed by the inhibition of mitochondrial complexes III and IV or alternative oxidase (AOX) and was blocked by the association of AOX with complex III or IV inhibitors. The expression of P. brasiliensis aox (Pbaox) was developmentally regulated through M-to-Y differentiation, wherein the highest levels were achieved in the first 24 h and during the yeast exponential growth phase; Pbaox was upregulated by oxidative stress. Pbaox was cloned, and its heterologous expression conferred cyanide-resistant respiration in Saccharomyces cerevisiae and Escherichia coli and reduced oxidative stress in S. cerevisiae cells. These results reinforce the role of PbAOX in intracellular redox balancing and demonstrate its involvement, as well as that of other components of the mitochondrial respiratory chain complexes, in the early stages of the M-to-Y differentiation of P. brasiliensis. PMID:21183691

Martins, Vicente P.; Dinamarco, Taisa M.; Soriani, Frederico M.; Tudella, Valéria G.; Oliveira, Sergio C.; Goldman, Gustavo H.; Curti, Carlos; Uyemura, Sérgio A.

2011-01-01

7

NLRP3 Inflammasome Activation by Paracoccidioides brasiliensis  

PubMed Central

Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis (PCM), the most prevalent systemic mycosis that is geographically confined to Latin America. The pro-inflammatory cytokine IL-1? that is mainly derived from the activation of the cytoplasmic multiprotein complex inflammasome is an essential host factor against opportunistic fungal infections; however, its role in infection with a primary fungal pathogen, such as P. brasiliensis, is not well understood. In this study, we found that murine bone marrow-derived dendritic cells responded to P. brasiliensis yeast cells infection by releasing IL-1? in a spleen tyrosine kinase (Syk), caspase-1 and NOD-like receptor (NLR) family member NLRP3 dependent manner. In addition, P. brasiliensis-induced NLRP3 inflammasome activation was dependent on potassium (K+) efflux, reactive oxygen species production, phagolysosomal acidification and cathepsin B release. Finally, using mice lacking the IL-1 receptor, we demonstrated that IL-1? signaling has an important role in killing P. brasiliensis by murine macrophages. Altogether, our results demonstrate that the NLRP3 inflammasome senses and responds to P. brasiliensis yeast cells infection and plays an important role in host defense against this fungus. PMID:24340123

Almeida, Raquel Das Neves; Correa, Rafael; Burgel, Pedro Henrique; Bocca, Anamélia Lorenzetti

2013-01-01

8

Hsp90 regulates Paracoccidioides brasiliensis proliferation and ROS levels under thermal stress and cooperates with calcineurin to control yeast to mycelium dimorphism.  

PubMed

Paracoccidioidomycosis is a systemic human mycosis in Latin America caused by Paracoccidioides brasiliensis, a dimorphic pathogenic fungus that lives as a mold in the environment and as yeast during infections of human lungs. In this work, we provide evidence that the inhibition of Hsp90 by geldanamycin (GDA) impairs the proliferation of the yeast, but has no effect on mycelial development. Treatment with cyclosporin A (CsA), an inhibitor of the Hsp90 client protein calcineurin, did not increase the effect of GDA. In contrast, GDA prevented mycelial to yeast differentiation through a mechanism partially dependent on calcineurin, whereas differentiation from yeast to mycelia occurred independent of GDA or CsA. A significant increase in reactive oxygen species (ROS) levels was detected in GDA-treated yeast at 42°C. However, the levels of ROS remained unchanged in GDA-treated yeast or mycelia incubated at 37°C, suggesting that Hsp90 plays different roles under normal and thermal stress conditions. We propose that Hsp90 strengthens the stress response of P. brasiliensis at 37°C through a mechanism that does not involve ROS. Moreover, we suggest that Hsp90 has calcineurin-dependent functions in this organism. PMID:23013413

Matos, Tatiana G F; Morais, Flavia V; Campos, Claudia B L

2013-05-01

9

Transcriptome characterization of the dimorphic and pathogenic fungusParacoccidioides brasiliensis by EST analysis  

Microsoft Academic Search

Paracoccidioides brasiliensis is a pathogenic fungus that undergoes a temperature- dependent cell morphology change from mycelium (22 ?C) to yeast (36 ?C). It is assumed that this morphological transition correlates with the infection of the human host. Our goal was to identify genes expressed in the mycelium (M) and yeast (Y) forms by EST sequencing in order to generate a

M. S. S. Felipe; R. V. Andrade; S. S. Petrofeza; F. A. G. Torres; P. Albuquerque; F. B. M. Arraes; M. Arruda; M. O. Azevedo; A. J. Baptista; L. A. M. Bataus; C. L. Borges; E. G. Campos; M. R. Cruz; B. S. Daher; A. Dantas; M. A. S. V. Ferreira; G. V. Ghil; R. S. A. Jesuino; C. M. Kyaw; C. R. Martins; L. M. P. Moraes; E. O. Neves; A. M. Nicola; E. S. Alves; J. A. Parente; M. Pereira; R. Resende; B. M. Ribeiro; R. R. Saldanha; S. C. Santos; I. Silva-Pereira; M. A. S. Silva; E. Silveira; R. B. A. Soares; D. P. Souza; M. T. De-Souza; E. V. Andrade; M. A. S. Xavier; H. P. Veiga; E. J. Venancio; M. J. A. Carvalho; A. G. Oliveira; M. K. Inoue; N. F. Almeida; M. E. M. T. Walter; C. M. A. Soares

2003-01-01

10

A Paracoccidioides brasiliensis glycan shares serologic and functional properties with cryptococcal glucuronoxylomannan  

PubMed Central

The cell wall of the yeast form of the dimorphic fungus Paracoccidioides brasiliensis is enriched with ?1,3-glucans. In Cryptococcus neoformans, ?1,3-glucans interact with glucuronoxylomannan (GXM), a hetero polysaccharide that is essential for fungal virulence. In this study, we investigated the occurrence of P. brasiliensis glycans sharing properties with cryptococcal GXM. Protein database searches in P. brasiliensis revealed the presence of sequences homologous to those coding for enzymes involved in the synthesis of GXM and capsular architecture in C. neoformans. In addition, monoclonal antibodies (mAbs) raised to cryptococcal GXM bound to P. brasiliensis cells. Using protocols that were previously established for extraction and analysis of C. neoformans GXM, we recovered a P. brasiliensis glycan fraction composed of mannose and galactose, in addition to small amounts of glucose, xylose and rhamnose. In comparison with the C. neoformans GXM, the P. brasiliensis glycan fraction components had smaller molecular dimensions. The P. brasiliensis components, nevertheless, reacted with different GXM-binding mAbs. Extracellular vesicle fractions of P. brasiliensis also reacted with a GXM-binding mAb, suggesting that the polysaccharide-like molecule is exported to the extracellular space in secretory vesicles. An acapsular mutant of C. neoformans incorporated molecules from the P. brasiliensis extract onto the cell wall, resulting in the formation of surface networks that resembled the cryptococcal capsule. Coating the C. neoformans acapsular mutant with the P. brasiliensis glycan fraction resulted in protection against phagocytosis by murine macrophages. These results suggest that P. brasiliensis and C. neoformans share metabolic pathways required for the synthesis of similar polysaccharides and that P. brasiliensis yeast cell walls have molecules that mimic certain aspects of C. neoformans GXM. These findings are important because they provide additional evidence for the sharing of antigenically similar components across phylogenetically distant fungal species. Since GXM has been shown to be important for the pathogenesis of C. neoformans and to elicit protective antibodies, the finding of similar molecules in P. brasiliensis raises the possibility that these glycans play similar functions in paracoccidiomycosis. PMID:23010152

Albuquerque, Priscila C.; Cordero, Radames J.B.; Fonseca, Fernanda L.; da Silva, Roberta Peres; Ramos, Caroline L.; Miranda, Kildare R.; Casadevall, Arturo; Puccia, Rosana; Nosanchuk, Joshua D.; Nimrichter, Leonardo; Guimaraes, Allan J.; Rodrigues, Marcio L.

2015-01-01

11

Detection of Antibodies against Paracoccidioides brasiliensis Melanin in In Vitro and In Vivo Studies during Infection ?  

PubMed Central

Several cell wall constituents, including melanins or melanin-like compounds, have been implicated in the pathogenesis of a wide variety of microbial diseases caused by diverse species of pathogenic bacteria, fungi, and helminthes. Among these microorganisms, the dimorphic fungal pathogen Paracoccidioides brasiliensis produces melanin in its conidial and yeast forms. In the present study, melanin particles from P. brasiliensis were injected into BALB/c mice in order to produce monoclonal antibodies (MAbs). We identified five immunoglobulin G1 (IgG1) ?-chain and four IgM melanin-binding MAbs. The five IgG1 ?-chain isotypes are the first melanin-binding IgG MAbs ever reported. The nine MAbs labeled P. brasiliensis conidia and yeast cells both in vitro and in pulmonary tissues. The MAbs cross-reacted with melanin-like purified particles from other fungi and also with commercial melanins, such as synthetic and Sepia officinalis melanin. Melanization during paracoccidioidomycosis (PCM) was also further supported by the detection of IgG antibodies reactive to melanin from P. brasiliensis conidia and yeast in sera and bronchoalveolar lavage fluids from P. brasiliensis-infected mice, as well as in sera from human patients with PCM. Serum specimens from patients with other mycoses were also tested for melanin-binding antibodies by enzyme-linked immunosorbent assay, and cross-reactivities were detected for melanin particles from different fungal sources. These results suggest that melanin from P. brasiliensis is an immunologically active fungal structure that activates a strong IgG humoral response in humans and mice. PMID:21813659

Urán, Martha E.; Nosanchuk, Joshua D.; Restrepo, Angela; Hamilton, Andrew J.; Gómez, Beatriz L.; Cano, Luz E.

2011-01-01

12

Alternative oxidase plays an important role in Paracoccidioides brasiliensis cellular homeostasis and morphological transition.  

PubMed

Paracoccidioides brasiliensis is the etiologic agent of one of the most common systemic mycoses in Latin America. As a dimorphic fungus, it must adapt to different environments during its life cycle, either in nature or within the host, enduring external stresses such as temperature or host-induced oxidative stress. In this study we addressed the role of alternative oxidase (PbAOX) in cellular homeostasis during batch culture growth and the morphological transition of P. brasiliensis. Using a PbAOX-antisense-RNA (PbAOX-aRNA) strain with a 70% reduction in gene expression, we show that PbAOX is crucial for maintaining cell viability and vitality during batch culture growth of yeast cells, in what appears to be a pH-dependent manner. We also show that silencing of PbAOX drastically reduced expression levels of other detoxifying enzymes (PbY20 and PbMSOD). In addition, our data indicate that PbAOX plays a role during the morphological transition, namely, during the yeast-to-mycelia germination and mycelia/conidia-to-yeast transition, essential events during the establishment of infection by dimorphic fungal pathogens. Altogether, our findings support the hypothesis that PbAOX is important for the maintenance of cellular homeostasis, possibly by assisting redox balancing during cell growth and the morphological switch of P. brasiliensis. PMID:25631476

Hernández, Orville; Araque, Pedronel; Tamayo, Diana; Restrepo, Angela; Herrera, Sebastian; Mcewen, Juan G; Pelaez, Carlos; Almeida, Agostinho J

2015-04-01

13

Cryptic Speciation and Recombination in the Fungus Paracoccidioides brasiliensis as Revealed by Gene Genealogies  

E-print Network

Cryptic Speciation and Recombination in the Fungus Paracoccidioides brasiliensis as Revealed and reproductive mode in this fungus, we analyzed P. brasiliensis phylogenetically in search of cryptic species of eight regions in five nuclear loci. Our data indicate that this fungus consists of at least three

14

Saccharomyces cerevisiae Expressing Gp43 Protects Mice against Paracoccidioides brasiliensis Infection  

PubMed Central

The dimorphic fungus Paracoccidioides brasiliensis is the etiological agent of paracoccidioidomycosis (PCM). It is believed that approximately 10 million people are infected with the fungus and approximately 2% will eventually develop the disease. Unlike viral and bacterial diseases, fungal diseases are the ones against which there is no commercially available vaccine. Saccharomyces cerevisiae may be a suitable vehicle for immunization against fungal infections, as they require the stimulation of different arms of the immune response. Here we evaluated the efficacy of immunizing mice against PCM by using S. cerevisiae yeast expressing gp43. When challenged by inoculation of P. brasiliensis yeasts, immunized animals showed a protective profile in three different assays. Their lung parenchyma was significantly preserved, exhibiting fewer granulomas with fewer fungal cells than found in non-immunized mice. Fungal burden was reduced in the lung and spleen of immunized mice, and both organs contained higher levels of IL-12 and IFN-? compared to those of non-vaccinated mice, a finding that suggests the occurrence of Th1 immunity. Taken together, our results indicate that the recombinant yeast vaccine represents a new strategy to confer protection against PCM. PMID:25790460

Assis-Marques, Mariana Aprigio; Oliveira, Aline Ferreira; Ruas, Luciana Pereira; dos Reis, Thaila Fernanda; Roque-Barreira, Maria Cristina; Coelho, Paulo Sergio Rodrigues

2015-01-01

15

Diversity in Paracoccidioides brasiliensis . The Pb GP43 gene as a genetic marker  

Microsoft Academic Search

Paracoccidioides brasiliensis is a temperature-dependent dimorphic fungus and the agent of paracoccidioidomycosis (PCM), which is prevalent in rural workers\\u000a of Latin American countries. Until a decade ago, most of the studies involving P. brasiliensis used clinical isolates, since environmental samples from soil are difficult to obtain. More recently, P. brasiliensis has been isolated from infected wild and domestic animals, especially

Rosana Puccia; Juan G. McEwen; Patrícia S. Cisalpino

2008-01-01

16

Mycelial Phase of Paracoccidioides brasiliensis and Blastomyces dermatitidis: an Electron Microscope Study  

PubMed Central

A comparative study of the mycelial phase of Paracoccidioides brasiliensis and Blastomyces dermatitidis reveals that both fungi are very much alike, containing multiple nuclei and nuclear pores, mitochondria, ribosomes, scarce endoplasmic reticulum, intracytoplasmic membrane systems, glycogen, and vacuoles. Shadowed cell walls show fine fibrillar surfaces that contrast with those in the yeast phase. The intracytoplasmic membrane system is continuous with the plasma membrane and is similar to bacterial mesosomes. Granules with light cores and dark rims are observed in the plasma membrane. Live hyphae growing inside a dead hypha are found much more frequently in immersed cultures than in solid-medium cultures, suggesting that breakage of the hypha could elicit this phenomenon. Images PMID:5674059

Carbonell, Luis M.; Rodriguez, Joaquin

1968-01-01

17

Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Differentiation of the Dimorphic Fungal Species Paracoccidioides brasiliensis and Paracoccidioides lutzii.  

PubMed

Isolates of Paracoccidioides brasiliensis and Paracoccidioides lutzii, previously characterized by molecular techniques, were identified for the first time by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). All isolates were correctly identified, with log score values of >2.0. Thus, MALDI-TOF MS is a new tool for differentiating species of the genus Paracoccidioides. PMID:25631803

Nobrega de Almeida, João; Del Negro, Gilda M B; Grenfell, Rafaella C; Vidal, Monica S M; Thomaz, Danilo Y; de Figueiredo, Dulce S Y; Bagagli, Eduardo; Juliano, Luiz; Benard, Gil

2015-04-01

18

The Pathogenic Fungus Paracoccidioides brasiliensis Exports Extracellular Vesicles Containing Highly Immunogenic ?-Galactosyl Epitopes?  

PubMed Central

Exosome-like vesicles containing virulence factors, enzymes, and antigens have recently been characterized in fungal pathogens, such as Cryptococcus neoformans and Histoplasma capsulatum. Here, we describe extracellular vesicles carrying highly immunogenic ?-linked galactopyranosyl (?-Gal) epitopes in Paracoccidioides brasiliensis. P. brasiliensis is a dimorphic fungus that causes human paracoccidioidomycosis (PCM). For vesicle preparations, cell-free supernatant fluids from yeast cells cultivated in Ham's defined medium-glucose were concentrated in an Amicon ultrafiltration system and ultracentrifuged at 100,000 × g. P. brasiliensis antigens were present in preparations from phylogenetically distinct isolates Pb18 and Pb3, as observed in immunoblots revealed with sera from PCM patients. In an enzyme-linked immunosorbent assay (ELISA), vesicle components containing ?-Gal epitopes reacted strongly with anti-?-Gal antibodies isolated from both Chagas' disease and PCM patients, with Marasmius oreades agglutinin (MOA) (a lectin that recognizes terminal ?-Gal), but only faintly with natural anti-?-Gal. Reactivity was inhibited after treatment with ?-galactosidase. Vesicle preparations analyzed by electron microscopy showed vesicular structures of 20 to 200 nm that were labeled both on the surface and in the lumen with MOA. In P. brasiliensis cells, components carrying ?-Gal epitopes were found distributed on the cell wall, following a punctuated confocal pattern, and inside large intracellular vacuoles. Lipid-free vesicle fractions reacted with anti-?-Gal in ELISA only when not digested with ?-galactosidase, while reactivity with glycoproteins was reduced after ?-elimination, which is indicative of partial O-linked chain localization. Our findings open new areas to explore in terms of host-parasite relationships in PCM and the role played in vivo by vesicle components and ?-galactosyl epitopes. PMID:21216942

Vallejo, Milene C.; Matsuo, Alisson L.; Ganiko, Luciane; Medeiros, Lia C. Soares; Miranda, Kildare; Silva, Luiz S.; Freymüller-Haapalainen, Edna; Sinigaglia-Coimbra, Rita; Almeida, Igor C.; Puccia, Rosana

2011-01-01

19

Importance of xenarthrans in the eco-epidemiology of Paracoccidioides brasiliensis  

Microsoft Academic Search

BACKGROUND: Several pathogens that cause important zoonotic diseases have been frequently associated with armadillos and other xenarthrans. This mammal group typically has evolved on the South American continent and many of its extant species are seriously threatened with extinction. Natural infection of armadillos with Paracoccidioides brasiliensis in hyperendemic areas has provided a valuable opportunity for understanding the role of this

Virgínia B Richini-Pereira; Sandra MG Bosco; Raquel C Theodoro; Lígia Barrozo; Silvia CB Pedrini; Patrícia S Rosa; Eduardo Bagagli

2009-01-01

20

Low-level Laser Therapy to the Mouse Femur Enhances the Fungicidal Response of Neutrophils against Paracoccidioides brasiliensis  

E-print Network

Neutrophils (PMN) play a central role in host defense against the neglected fungal infection paracoccidioidomycosis (PCM), which is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb). PCM is of major importance, ...

Burger, Eva

21

Expression of Paracoccidioides brasiliensis AMY1 in a Histoplasma capsulatum amy1 Mutant, Relates an ?-(1,4)-Amylase to Cell Wall ?-(1,3)-Glucan Synthesis  

PubMed Central

In the cell walls of the pathogenic yeast phases of Paracoccidioides brasiliensis, Blastomyces dermatitidis and Histoplasma capsulatum, the outer ?-(1,3)-glucan layer behaves as a virulence factor. In H. capsulatum, an ?-(1,4)-amylase gene (AMY1) is essential for the synthesis of this polysaccharide, hence related to virulence. An orthologous gene to H. capsulatum AMY1 was identified in P. brasiliensis and also labeled AMY1. P. brasiliensis AMY1 transcriptional levels were increased during the yeast phase, which correlates with the presence of ?-(1,3)-glucan as the major yeast cell wall polysaccharide. Complementation of a H. capsulatum amy1 mutant strain with P. brasiliensis AMY1, suggests that P. brasiliensis Amy1p may play a role in the synthesis of cell wall ?-(1,3)-glucan. To study some biochemical properties of P. brasiliensis Amy1p, the enzyme was overexpressed, purified and studied its activity profile with starch and amylopeptin. It showed a relatively higher hydrolyzing activity on amylopeptin than starch, producing oligosaccharides from 4 to 5 glucose residues. Our findings show that P. brasiliensis Amy1p produces maltooligosaccharides which may act as a primer molecule for the fungal cell wall ?-(1,3)-glucan biosynthesis by Ags1p. PMID:23185578

Camacho, Emma; Sepulveda, Victoria E.; Goldman, William E.; San-Blas, Gioconda; Niño-Vega, Gustavo A.

2012-01-01

22

Paracoccidioides brasiliensis Interferes on Dendritic Cells Maturation by Inhibiting PGE2 Production  

PubMed Central

Paracoccidioidomycosis (PCM) is a systemic mycosis, endemic in most Latin American countries, especially in Brazil, whose etiologic agent is the thermodimorphic fungus of the genus Paracoccidioides, comprising cryptic species of Paracoccidioides brasiliensis, S1, PS2, PS3 and Paracoccidioides lutzii. The mechanisms involved in the initial interaction of the fungus with cells of the innate immune response, as dendritic cells (DCs), deserve to be studied. Prostaglandins (PGs) are eicosanoids that play an important role in modulating functions of immune cells including DCs. Here we found that human immature DCs derived from the differentiation of monocytes cultured with GM-CSF and IL-4 release substantial concentrations of PGE2, which, however, were significantly inhibited after challenge with P. brasiliensis. In vitro blocking of pattern recognition receptors (PRRs) by monoclonal antibodies showed the involvement of mannose receptor (MR) in PGE2 inhibition by the fungus. In addition, phenotyping assays showed that after challenge with the fungus, DCs do not change their phenotype of immature cells to mature ones, as well as do not produce IL-12 p70 or adequate concentrations of TNF-?. Assays using exogenous PGE2 confirmed an association between PGE2 inhibition and failure of cells to phenotypically mature in response to P. brasiliensis. We conclude that a P. brasiliensis evasion mechanism exists associated to a dysregulation on DC maturation. These findings may provide novel information for the understanding of the complex interplay between the host and this fungus. PMID:25793979

2015-01-01

23

New Developments of RNAi in Paracoccidioides brasiliensis: Prospects for High-Throughput, Genome-Wide, Functional Genomics  

PubMed Central

Background The Fungal Genome Initiative of the Broad Institute, in partnership with the Paracoccidioides research community, has recently sequenced the genome of representative isolates of this human-pathogen dimorphic fungus: Pb18 (S1), Pb03 (PS2) and Pb01. The accomplishment of future high-throughput, genome-wide, functional genomics will rely upon appropriate molecular tools and straightforward techniques to streamline the generation of stable loss-of-function phenotypes. In the past decades, RNAi has emerged as the most robust genetic technique to modulate or to suppress gene expression in diverse eukaryotes, including fungi. These molecular tools and techniques, adapted for RNAi, were up until now unavailable for P. brasiliensis. Methodology/Principal Findings In this paper, we report Agrobacterium tumefaciens mediated transformation of yeast cells for high-throughput applications with which higher transformation frequencies of 150±24 yeast cell transformants per 1×106 viable yeast cells were obtained. Our approach is based on a bifunctional selective marker fusion protein consisted of the Streptoalloteichus hindustanus bleomycin-resistance gene (Shble) and the intrinsically fluorescent monomeric protein mCherry which was codon-optimized for heterologous expression in P. brasiliensis. We also report successful GP43 gene knock-down through the expression of intron-containing hairpin RNA (ihpRNA) from a Gateway-adapted cassette (cALf) which was purpose-built for gene silencing in a high-throughput manner. Gp43 transcript levels were reduced by 73.1±22.9% with this approach. Conclusions/Significance We have a firm conviction that the genetic transformation technique and the molecular tools herein described will have a relevant contribution in future Paracoccidioides spp. functional genomics research. PMID:25275433

Goes, Tercio; Bailão, Elisa Flavia L. C.; Correa, Cristiane R.; Bozzi, Adriana; Santos, Luara I.; Gomes, Dawidson A.; Soares, Celia M. A.; Goes, Alfredo M.

2014-01-01

24

Characterization of gp70 and Anti-gp70 Monoclonal Antibodies in Paracoccidioides brasiliensis Pathogenesis  

Microsoft Academic Search

Paracoccidioidomycosis (PCM) is a systemic granulomatous mycosis whose agent is Paracoccidioides bra- siliensis. In the culture supernatant, the fungus expresses glycoproteins of from 13 to 148 kDa. A cell surface glycoprotein of 43 kDa is the major antigenic component of P. brasiliensis. Another expressed glycoprotein, gp70, is recognized by 96% of sera from PCM patients and is able to induce

Daniela de Mattos Grosso; Sandro Rogerio de Almeida; Mario Mariano; Jose Daniel Lopes

2003-01-01

25

Differential antibody isotype expression to the major Paracoccidioides brasiliensis antigen in juvenile and adult form paracoccidioidomycosis  

Microsoft Academic Search

We investigated the relationship between antibody response to the major Paracoccidioides brasiliensis antigen, a 43-kDa glycoprotein, and the two paracoccidioidomycosis (PCM) clinical presentations, the juvenile and the adult forms. Total immunoglobulin G (IgG), IgG isotypes, and IgA anti-gp43 antibodies were determined by enzyme-linked immunosorbent assay in patients'sera. Juvenile PCM patients had higher (P =.003) IgG anti-gp43 levels than adult form

Heide Baida; Michelangelo Juvenale; Gil Benard

1999-01-01

26

Paracoccidioides brasiliensis : chemical and molecular tools for research on cell walls, antifungals, diagnosis, taxonomy  

Microsoft Academic Search

Paracoccidioides brasiliensis is a dimorphic fungus, a causative agent of paracoccidioidomycosis, one of the most frequent systemic mycoses that affect\\u000a the rural population in Latin America, only geographical region in which this fungus is to be found. In this work, we discuss\\u000a matters related to (a) cell wall studies based on the cloning and analysis of genes involved in the

Gioconda San-Blas; Gustavo Niño-Vega

2008-01-01

27

Involvement of the 90 kDa heat shock protein during adaptation of Paracoccidioides brasiliensis to different environmental conditions.  

PubMed

HSP90 is a molecular chaperone that participates in folding, stabilization, activation, and assembly of several proteins, all of which are key regulators in cell signaling. In dimorphic pathogenic fungi such as Paracoccidioides brasiliensis, the adaptation to a higher temperature, acid pH and oxidative stress, is an essential event for fungal survival and also for the establishing of the infectious process. To further understand the role of this protein, we used antisense RNA technology to generate a P. brasiliensis isolate with reduced PbHSP90 gene expression (PbHSP90-aRNA). Reduced expression of HSP90 decreased yeast cell viability during batch culture growth and increased susceptibility to acid pH environments and imposed oxidative stress. Also, PbHSP90-aRNA yeast cells presented reduced viability upon interaction with macrophages. The findings presented here suggest a protective role for HSP90 during adaptation to hostile environments, one that promotes survival of the fungus during host-pathogen interactions. PMID:23207691

Tamayo, Diana; Muñoz, Jose F; Torres, Isaura; Almeida, Agostinho J; Restrepo, Angela; McEwen, Juan G; Hernández, Orville

2013-02-01

28

Melanin as a virulence factor of Paracoccidioides brasiliensis and other dimorphic pathogenic fungi  

PubMed Central

Melanin pigments are substances produced by a broad variety of pathogenic microorganisms, including bacteria, fungi, and helminths. Microbes predominantly produce melanin pigment via tyrosinases, laccases, catecholases, and the polyketide synthase pathway. In fungi, melanin is deposited in the cell wall and cytoplasm, and melanin particles (“ghosts”) can be isolated from these fungi that have the same size and shape of the original cells. Melanin has been reported in several human pathogenic dimorphic fungi including Paracoccidioides brasiliensis, Sporothrix schenckii, Histoplasma capsulatum, Blastomyces dermatitidis, and Coccidioides posadasii. Melanization appears to contribute to virulence by reducing the susceptibility of melanized fungi to host defense mechanisms and antifungal drugs. PMID:18777637

Taborda, Carlos P.; da Silva, Marcelo B.; Nosanchuk, Joshua D.; Travassos, Luiz R.

2008-01-01

29

Cryptic speciation and recombination in the fungus Paracoccidioides brasiliensis as revealed by gene genealogies.  

PubMed

Paracoccidioides brasiliensis is the etiologic agent of paracoccidioidomycosis, a disease confined to Latin America and of marked importance in the endemic areas due to its frequency and severity. This species is considered to be clonal according to mycological criteria and has been shown to vary in virulence. To characterize natural genetic variation and reproductive mode in this fungus, we analyzed P. brasiliensis phylogenetically in search of cryptic species and possible recombination using concordance and nondiscordance of gene genealogies with respect to phylogenies of eight regions in five nuclear loci. Our data indicate that this fungus consists of at least three distinct, previously unrecognized species: S1 (species 1 with 38 isolates), PS2 (phylogenetic species 2 with six isolates), and PS3 (phylogenetic species 3 with 21 isolates). Genealogies of four of the regions studied strongly supported the PS2 clade, composed of five Brazilian and one Venezuelan isolate. The second clade, PS3, composed solely of 21 Colombian isolates, was strongly supported by the alpha-tubulin genealogy. The remaining 38 individuals formed S1. Two of the three lineages of P. brasiliensis, S1 and PS2, are sympatric across their range, suggesting barriers to gene flow other than geographic isolation. Our study provides the first evidence for possible sexual reproduction in P. brasiliensis S1, but does not rule it out in the other two species. PMID:16151188

Matute, Daniel R; McEwen, Juan G; Puccia, Rosana; Montes, Beatriz A; San-Blas, Gioconda; Bagagli, Eduardo; Rauscher, Jason T; Restrepo, Angela; Morais, Favia; Niño-Vega, Gustavo; Taylor, John W

2006-01-01

30

Inhibition of PbGP43 Expression May Suggest that gp43 is a Virulence Factor in Paracoccidioides brasiliensis  

PubMed Central

Glycoprotein gp43 is an immunodominant diagnostic antigen for paracoccidioidomycosis caused by Paracoccidioides brasiliensis. It is abundantly secreted in isolates such as Pb339. It is structurally related to beta-1,3-exoglucanases, however inactive. Its function in fungal biology is unknown, but it elicits humoral, innate and protective cellular immune responses; it binds to extracellular matrix-associated proteins. In this study we applied an antisense RNA (aRNA) technology and Agrobacterium tumefaciens-mediated transformation to generate mitotically stable PbGP43 mutants (PbGP43 aRNA) derived from wild type Pb339 to study its role in P. brasiliensis biology and during infection. Control PbEV was transformed with empty vector. Growth curve, cell vitality and morphology of PbGP43 aRNA mutants were indistinguishable from those of controls. PbGP43 expression was reduced 80–85% in mutants 1 and 2, as determined by real time PCR, correlating with a massive decrease in gp43 expression. This was shown by immunoblotting of culture supernatants revealed with anti-gp43 mouse monoclonal and rabbit polyclonal antibodies, and also by affinity-ligand assays of extracellular molecules with laminin and fibronectin. In vitro, there was significantly increased TNF-? production and reduced yeast recovery when PbGP43 aRNA1 was exposed to IFN-?-stimulated macrophages, suggesting reduced binding/uptake and/or increased killing. In vivo, fungal burden in lungs of BALB/c mice infected with silenced mutant was negligible and associated with decreased lung ???10 and IL-6. Therefore, our results correlated low gp43 expression with lower pathogenicity in mice, but that will be definitely proven when PbGP43 knockouts become available. This is the first study of gp43 using genetically modified P. brasiliensis. PMID:23874627

Torres, Isaura; Hernandez, Orville; Tamayo, Diana; Muñoz, Jose F.; Leitão, Natanael P.; García, Ana M.; Restrepo, Angela

2013-01-01

31

Recombinant Paracoccin Reproduces the Biological Properties of the Native Protein and Induces Protective Th1 Immunity against Paracoccidioides brasiliensis Infection  

PubMed Central

Background Paracoccin is a dual-function protein of the yeast Paracoccidioides brasiliensis that has lectin properties and N-acetylglucosaminidase activities. Proteomic analysis of a paracoccin preparation from P. brasiliensis revealed that the sequence matched that of the hypothetical protein encoded by PADG-3347 of isolate Pb-18, with a polypeptide sequence similar to the family 18 endochitinases. These endochitinases are multi-functional proteins, with distinct lectin and enzymatic domains. Methodology/principal findings The multi-exon assembly and the largest exon of the predicted ORF (PADG-3347), was cloned and expressed in Escherichia coli cells, and the features of the recombinant proteins were compared to those of the native paracoccin. The multi-exon protein was also used for protection assays in a mouse model of paracoccidioidomycosis. Conclusions/Significance Our results showed that the recombinant protein reproduced the biological properties described for the native protein—including binding to laminin in a manner that is dependent on carbohydrate recognition—showed N-acetylglucosaminidase activity, and stimulated murine peritoneal macrophages to produce high levels of TNF-? and nitric oxide. Considering the immunomodulatory potential of glycan-binding proteins, we also investigated whether prophylactic administration of recombinant paracoccin affected the course of experimental paracoccidioidomycosis in mice. In comparison to animals injected with vehicle (controls), mice treated with recombinant paracoccin displayed lower pulmonary fungal burdens and reduced pulmonary granulomas. These protective effects were associated with augmented pulmonary levels of IL-12 and IFN-?. We also observed that injection of paracoccin three days before challenge was the most efficient administration protocol, as the induced Th1 immunity was balanced by high levels of pulmonary IL-10, which may prevent the tissue damage caused by exacerbated inflammation. The results indicated that paracoccin is the protein encoded by PADG-3347, and we propose that this gene and homologous proteins in other P. brasiliensis strains be called paracoccin. We also concluded that recombinant paracoccin confers resistance to murine P. brasiliensis infection by exerting immunomodulatory effects. PMID:24743161

Alegre, Ana Claudia Paiva; Oliveira, Aline Ferreira; Dos Reis Almeida, Fausto Bruno; Roque-Barreira, Maria Cristina; Hanna, Ebert Seixas

2014-01-01

32

Correlation between Histopathological and FT-Raman Spectroscopy Analysis of the Liver of Swiss Mice Infected with Paracoccidioides brasiliensis  

PubMed Central

Paracoccidioidomycosis is the most important systemic mycosis in Latin America. The main entrance of the fungus is the airway. It primarily occurs in the lung, but in its disseminated form may affect any organ. The liver is one of the organs afflicted by this disease and its homeostasis may be impaired. The aim of the present study was to evaluate the evolution of paracoccidioidomycosis in the liver of Swiss mice and correlate morphological factors with the expression of gp43 and with physicochemical analysis via FT-Raman of the infected organ. According to colony forming unit (CFU) and granuloma counting, the first and second weeks were the periods when infection was most severe. Tissue response was characterized by the development of organized granulomas and widespread infection, with yeasts located within the macrophages and isolated hepatocytes. The gp43 molecule was distributed throughout the hepatic parenchyma, and immunostaining was constant in all observed periods. The main physicochemical changes of the infected liver were observed in the spectral ranges between 1700–1530 cm?1 and 1370 – 1290 cm?1, a peak shifting center attributed to phenylalanine and area variation of -CH2 and -CH3 compounds associated to collagen, respectively. Over time, there was a direct proportional relationship between the number of CFUs, the number of granulomas and the physicochemical changes in the liver of mice infected with Paracoccidioides brasiliensis. The expression of gp43 was similar in all observed periods. PMID:25181524

Mansano, Elaine Sciuniti Benites; de Morais, Gutierrez Rodrigues; Moratto, Edilaine Martins; Sato, Francielle; Medina Neto, Antonio; Svidzinski, Terezinha Ines Estivalet; Baesso, Mauro Luciano; Hernandes, Luzmarina

2014-01-01

33

Importance of xenarthrans in the eco-epidemiology of Paracoccidioides brasiliensis  

PubMed Central

Background Several pathogens that cause important zoonotic diseases have been frequently associated with armadillos and other xenarthrans. This mammal group typically has evolved on the South American continent and many of its extant species are seriously threatened with extinction. Natural infection of armadillos with Paracoccidioides brasiliensis in hyperendemic areas has provided a valuable opportunity for understanding the role of this mammal in the eco-epidemiology of Paracoccidioidomycosis (PCM), one of the most important systemic mycoses in Latin America. Findings This study aimed to detect P. brasiliensis in different xenarthran species (Dasypus novemcinctus, Cabassous spp., Euphractus sexcinctus, Tamandua tetradactyla and Myrmecophaga tridactyla), by molecular and mycological approaches, in samples obtained by one of the following strategies: i) from road-killed animals (n = 6); ii) from naturally dead animals (n = 8); iii) from animals that died in captivity (n = 9); and iv) from living animals captured from the wild (n = 2). Specific P. brasiliensis DNA was detected in several organs among 7/20 nine-banded armadillos (D. novemcinctus) and in 2/2 anteaters (M. tridactyla). The fungus was also cultured in tissue samples from one of two armadillos captured from the wild. Conclusion Members of the Xenarthra Order, especially armadillos, have some characteristics, including a weak cellular immune response and low body temperature, which make them suitable models for studying host-pathogen interaction. P. brasiliensis infection in wild animals, from PCM endemic areas, may be more common than initially postulated and reinforces the use of these animals as sentinels for the pathogen in the environment. PMID:19919716

2009-01-01

34

The transcriptome analysis of early morphogenesis in Paracoccidioides brasiliensis mycelium reveals novel and induced genes potentially associated to the dimorphic process  

PubMed Central

Background Paracoccidioides brasiliensis is a human pathogen with a broad distribution in Latin America. The fungus is thermally dimorphic with two distinct forms corresponding to completely different lifestyles. Upon elevation of the temperature to that of the mammalian body, the fungus adopts a yeast-like form that is exclusively associated with its pathogenic lifestyle. We describe expressed sequence tags (ESTs) analysis to assess the expression profile of the mycelium to yeast transition. To identify P. brasiliensis differentially expressed sequences during conversion we performed a large-scale comparative analysis between P. brasiliensis ESTs identified in the transition transcriptome and databases. Results Our analysis was based on 1107 ESTs from a transition cDNA library of P. brasiliensis. A total of 639 consensus sequences were assembled. Genes of primary metabolism, energy, protein synthesis and fate, cellular transport, biogenesis of cellular components were represented in the transition cDNA library. A considerable number of genes (7.51%) had not been previously reported for P. brasiliensis in public databases. Gene expression analysis using in silico EST subtraction revealed that numerous genes were more expressed during the transition phase when compared to the mycelial ESTs [1]. Classes of differentially expressed sequences were selected for further analysis including: genes related to the synthesis/remodeling of the cell wall/membrane. Thirty four genes from this family were induced. Ten genes related to signal transduction were increased. Twelve genes encoding putative virulence factors manifested increased expression. The in silico approach was validated by northern blot and semi-quantitative RT-PCR. Conclusion The developmental program of P. brasiliensis is characterized by significant differential positive modulation of the cell wall/membrane related transcripts, and signal transduction proteins, suggesting the related processes important contributors to dimorphism. Also, putative virulence factors are more expressed in the transition process suggesting adaptation to the host of the yeast incoming parasitic phase. Those genes provide ideal candidates for further studies directed at understanding fungal morphogenesis and its regulation. PMID:17425801

Bastos, Karinne P; Bailão, Alexandre M; Borges, Clayton L; Faria, Fabricia P; Felipe, Maria SS; Silva, Mirelle G; Martins, Wellington S; Fiúza, Rogério B; Pereira, Maristela; Soares, Célia MA

2007-01-01

35

Expression of Antibodies Directed to Paracoccidioides brasiliensis Glycosphingolipids during the Course of Paracoccidioidomycosis Treatment?  

PubMed Central

Paracoccidioidomycosis (PCM) is a granulomatous disease caused by the dimorphic fungus Paracoccidioides brasiliensis. The immunoglobulin classes and isotypes of antibodies directed to acidic glycosphingolipids (GSLs) and glucosylceramide of P. brasiliensis were determined by enzyme-linked immunosorbent assay of sera from 31 PCM patients. The reactivities of 38 serum samples were analyzed by considering the stage of treatment: before antifungal treatment (n = 10), during 1 to 4 months of treatment (T1-4; n = 9), during 5 to 12 months of treatment (T5-12; n = 9), and posttreatment (PT; n = 10). Sera from healthy subjects (n = 12) were used as controls. Only the GSL Pb-1 antigen, which presents the carbohydrate structure Galf?1-6(Man?1-3)Man?1, was reactive with the PCM patient sera. The PCM patient sera did not react with Pb-2, which lacks the Galf residue and which is considered the biosynthetic precursor of Pb-1, indicating that the Galf residue is essential for antibody reactivity. The Pb-1 glycolipid from nontreated patients elicited a primary immune response with immunoglobulin M (IgM) production and subsequent switching to IgG1 production. The IgG1 titer increased after the start of antifungal treatment (T1-4 group), and general decreases in the anti-Pb-1 antibody titers were observed after 5 months of treatment (T5-12 and PT groups). The Pb-1 antigen, an acidic GSL with terminal Galf residue, has potential application as an elicitor of the host immune response in patients with PCM. PMID:17135452

Bertini, Silvio; Colombo, Arnaldo L.; Takahashi, Helio K.; Straus, Anita H.

2007-01-01

36

Therapeutic Administration of Recombinant Paracoccin Confers Protection against Paracoccidioides brasiliensis Infection: Involvement of TLRs  

PubMed Central

Background Paracoccin (PCN) is an N-acetylglucosamine-binding lectin from the human pathogenic fungus Paracoccidioides brasiliensis. Recombinant PCN (rPCN) induces a T helper (Th) 1 immune response when prophylactically administered to BALB/c mice, protecting them against subsequent challenge with P. brasiliensis. In this study, we investigated the therapeutic effect of rPCN in experimental paracoccidioidomycosis (PCM) and the mechanism accounting for its beneficial action. Methodology/Principal Findings Four distinct regimens of rPCN administration were assayed to identify which was the most protective, relative to vehicle administration. In all rPCN-treated mice, pulmonary granulomas were less numerous and more compact. Moreover, fewer colony-forming units were recovered from the lungs of rPCN-treated mice. Although all therapeutic regimens of rPCN were protective, maximal efficacy was obtained with two subcutaneous injections of 0.5 µg rPCN at 3 and 10 days after infection. The rPCN treatment was also associated with higher pulmonary levels of IL-12, IFN-?, TNF-?, nitric oxide (NO), and IL-10, without IL-4 augmentation. Encouraged by the pulmonary cytokine profile of treated mice and by the fact that in vitro rPCN-stimulated macrophages released high levels of IL-12, we investigated the interaction of rPCN with Toll-like receptors (TLRs). Using a reporter assay in transfected HEK293T cells, we verified that rPCN activated TLR2 and TLR4. The activation occurred independently of TLR2 heterodimerization with TLR1 or TLR6 and did not require the presence of the CD14 or CD36 co-receptors. The interaction between rPCN and TLR2 depended on carbohydrate recognition because it was affected by mutation of the receptor's N-glycosylation sites. The fourth TLR2 N-glycan was especially critical for the rPCN-TLR2 interaction. Conclusions/Significance Based on our results, we propose that PCN acts as a TLR agonist. PCN binds to N-glycans on TLRs, triggers regulated Th1 immunity, and exerts a therapeutic effect against P. brasiliensis infection. PMID:25474158

Alegre-Maller, Ana Claudia Paiva; Mendonça, Flávia Costa; da Silva, Thiago Aparecido; Oliveira, Aline Ferreira; Freitas, Mateus Silveira; Hanna, Ebert Seixas; Almeida, Igor C.; Gay, Nicholas J.; Roque-Barreira, Maria Cristina

2014-01-01

37

The kex2 gene from the dimorphic and human pathogenic fungus Paracoccidioides brasiliensis.  

PubMed

Kexin-like protein is a component of the subtilase family of proteinases involved in the processing of proproteins to their active forms. Kexin-like proteins are also synthesized as a propeptide and this is involved in (auto)inhibition, correct folding and subcellular sorting of proteins. The kexin-like protein was described as the product of the kex2 gene for Aspergillus niger, Candida albicans, Saccharomyces cerevisiae, Yarrowia lipolytica and other fungi. Disruption of the kex2 gene in C. albicans and Y. lipolytica affects hyphae production and induces morphological cell defects, strongly suggesting a possible role of kexin-like proteins in dimorphism of human pathogenic fungi. In this work, we report the nucleotide sequence of the kex2 gene cloned from the dimorphic and human pathogenic fungus Paracoccidioides brasiliensis (Pbkex2). An open reading frame (ORF) of 2622 bp was identified in the complete sequence, interrupted by only one intron of 93 bp. The 5' non-coding region contains consensus sequences such as canonical TATA, CAAT boxes and putative motifs for transcriptional factors binding sites, such as HSE-like regulating genes involved in thermo-dependent processes; Xbp1, reported as a transcriptional factor that may control genes involved in cell morphology; and StuAp, which may regulate spore differentiation and pseudohyphal growth in fungi. In the 3' non-coding region were observed the canonical motifs necessary for correct mRNA processing and polyadenylation. The deduced protein sequence consists of 842 amino acid residues, showing identity to kexin-like proteinases from A. niger (55%), Emericella nidulans (53%) and C. albicans (48%). Comparative sequence analysis of P. brasiliensis kexin-like protein reveals the presence of homologous regions related to a signal peptide, a propeptide, a subtilisin-like catalytic domain, a P domain, a S/T rich region and a transmembrane domain. A putative Golgi retrieval signal (YEFEMI) has also been found in the cytoplasmic tail. The complete nucleotide sequence of Pbkex2 and its flanking regions have been submitted to GenBank database under Accession No. AF486805. PMID:12271458

Venancio, Emerson J; Daher, Bruno S; Andrade, Rosângela V; Soares, Célia M A; Pereira, Ildinete Silva; Felipe, Maria Sueli S

2002-10-01

38

A case of paracoccidioidal granuloma in norther Nigeria.  

PubMed

A case of Paracoccidioidal granuloma in Northern Nigeria is presented. The fungus could be cultured and identified as Paracoccidioides brasiliensis. Histology revealed a fungal lesion due to a yeast like organism. The patient responded to long acting Sulphormethoxine (Fanasil). A variation from the classic histopathological description and association of pustular psoriasiform lesions on the soles with a possibility of 'Id' reaction to the fungus are discussed. PMID:537129

Lawande, R V; Sturrock, R D; Jacyk, W K; Subbuswamy, S G

1979-08-01

39

Antifungal activity of schinol and a new biphenyl compound isolated from Schinus terebinthifolius against the pathogenic fungus Paracoccidioides brasiliensis  

PubMed Central

Background The aim of this study was to isolate and identify the antifungal compounds from the extracts of Schinus terebinthifolius (Anacardiaceae) against clinical isolates of the pathogenic fungus Paracoccidioides brasiliensis. Methods The hexane and dichlomethane fractions from leaves and stems of S. terebinthifolius were fractionated using several chromatography techniques to afford four compounds. Results The compounds isolated from S. terebinthifolius were identified as schinol (1), a new biphenyl compound, namely, 4'-ethyl-4-methyl-2,2',6,6'-tetrahydroxy[1,1'-biphenyl]-4,4'-dicarboxylate (2), quercetin (3), and kaempferol (4). Compounds 1 and 2 were active against different strains of P. brasiliensis, showing a minimal inhibitory concentration value against the isolate Pb B339 of 15.6 ?g/ml. The isolate Pb 1578 was more sensitive to compound 1 with a MIC value of 7.5 ?g/ml. Schinol presented synergistic effect only when combined with itraconazole. The compounds isolated from S. terebinthifolius were not able to inhibit cell wall synthesis or assembly using the sorbitol assay. Conclusion This work reveals for the first time the occurrence of compound 2 and discloses activity of compounds 1 and 2 against several clinical isolates of P. brasiliensis. These results justify further studies to clarify the mechanisms of action of these compounds. PMID:20939907

2010-01-01

40

Identification of transcription elements in the 5? intergenic region shared by LON and MDJ1 heat shock genes from the human pathogen Paracoccidioides brasiliensis. Evaluation of gene expression  

Microsoft Academic Search

The MDJ1\\/LON locus is conserved among pathogenic dimorphic fungi. We have mapped using DNase I footprinting and mobility shift assays three putative heat shock elements and one AP-1 binding domain (ARE) in the 5? intergenic region shared by PbMDJ1and PbLON (ML) from Paracoccidioides brasiliensis. The region bearing an ARE-like towards PbLON also has an opposite skn-1-like element. We studied genetically

Wagner L. Batista; Tânia F. Barros; Gustavo H. Goldman; Flávia V. Morais; Rosana Puccia

2007-01-01

41

A primary subcutaneous infection with Paracoccidioides brasiliensis leads to immunoprotection or exacerbated disease depending on the route of challenge.  

PubMed

In human and experimental paracoccidioidomycosis the severe disease is characterized by depressed cellular immunity whereas the mild disease is associated with persistent T cell immunity. Since the subcutaneous route of antigen inoculation is an efficient inducer of cellular immunity, we decided to study this route of infection and verify its effect on a lethal secondary infection of susceptible hosts. It was observed that the s.c. infection induces positive delayed type hypersensitivity (DTH) responses in 9 different mouse strains, is a self healing process and susceptible mice develop more intense DTH reactions than resistant mice to Paracoccidioides brasiliensis infection. Unexpectedly, the previous s.c. infection of susceptible mice led to immunoprotection or disease exacerbation depending on the route of fungal challenge. Immunoprotection was achieved after intraperitoneal challenge and was associated with persistent cell-mediated immunity and a mixed type-1/type-2 immunity. Exacerbated disease was found after intravenous challenge, was associated with cellular immunity anergy and prevalent type-2 immune response. As a whole, our work demonstrates that susceptibility to P. brasiliensis infection cannot be ascribed to intrinsic inability to mount cellular immune responses, that a single immunization procedure can result in opposite disease outcomes and immunoprotection can be achieved by a balanced Th1/Th2 immunity. PMID:17306589

Arruda, Celina; Kashino, Suely S; Fazioli, Raquel A; Calich, Vera L G

2007-03-01

42

Paracoccidioides lutzii Plp43 Is an Active Glucanase with Partial Antigenic Identity with P. brasiliensis gp43  

PubMed Central

Background Paracoccidioides brasiliensis and P. lutzii cause paracoccidioidomycosis (PCM). P. brasiliensis main diagnostic antigen is glycoprotein gp43, and its peptide sequence is 81% identical with a P. lutzii ortholog here called Plp43. P. lutzii (“Pb01-like”) apparently predominates in Midwestern/Northern Brazil, where high percentages of false-negative reactions using P. brasiliensis antigens have recently been reported. The aim of this work was to produce recombinant Plp43 to study its antigenic identity with gp43. Methodology We expressed rPlp43 as a secreted major component in Pichia pastoris and studied its reactivity in immunoblot with PCM patients' sera from Southwestern and Midwestern Brazil. Principal Findings We showed that rPlp43 is not glycosylated and bears glucanase activity. The protein did not react with anti-gp43 monoclonal antibodies in immunoblot, suggesting absence of the corresponding gp43 epitopes. Nevertheless, common epitope(s) might exist, considering that gp43-positive PCM sera recognized rPlp43 in immunoblot, while gp43-negative sera (33 out of 51) from patients resident in Midwestern Brazil were also rPlp43-negative. Two genotyped P. lutzii were from patients with gp43-negative sera, suggesting that non-reactive sera are from patients infected with this species. Conclusion Our data suggest that gp43 and Plp43 bear one or only a few common epitopes and that gp43 cannot be used in diagnosis of PCM patients infected with P. lutzii probably because Plp43 is poorly expressed during infection. PMID:25166744

Leitão, Natanael P.; Vallejo, Milene C.; Conceição, Palloma M.; Camargo, Zoilo P.; Hahn, Rosane; Puccia, Rosana

2014-01-01

43

B and T cell responses elicited by monoclonal anti-idiotypic antibody (Ab2?) mimicking gp43 from Paracoccidioides brasiliensis  

PubMed Central

Paracoccidioidomycosis is a systemic mycosis endemic in Latin America, with a high prevalence in Brazil, Argentina, Colombia and Venezuela. The aetiological agent of disease is the thermal dimorphic fungus, Paracoccidioides brasiliensis. A glycoprotein of 43 kD (gp43) is the major antigen of P. brasiliensis. Antibodies directed to this antigen are detected in the sera of all patients with paracoccidioidomycosis (PCM). Recently, it has been shown that mice immunized with anti-gp43 monoclonal antibodies (MAbs) (Ab1), induce the idiotypic cascade in the gp43 system, which produced both, anti-Id antibodies (Ab2) and anti-anti-Id antibodies (Ab3). To further characterize the idiotypic cascade modulation in mice immunized with anti-gp43 MAb 17c, hybridomas were produced. Ab2 MAbs named 7.B12 inhibited (>95%) the binding of gp43 to MAb 17c (Ab1), suggesting that this anti-Id MAb bind to the idiotope, thus fulfilling the internal image criteria. To elucidate whether Ab2 MAb could act as antigen in serological assays, instead of gp43, sera from PCM patients were tested. Using an ELISA test, it was observed that antibodies from patients and not normal serum bound to Ab2. However, the ELISA test using Ab2 bound to the solid phase made possible to serologically monitor the patients after antifungal therapy, showing an equivalent curve when compared with ELISA test employing purified gp43. Our results also showed that, when mice were immunized with Ab2? and their cells were exposed to gp43 in vitro, a T cell proliferation response was observed. PMID:15196252

SOUZA, E B; LOPES, J D; ALMEIDA, S R

2004-01-01

44

Low-level laser therapy to the mouse femur enhances the fungicidal response of neutrophils against Paracoccidioides brasiliensis.  

PubMed

Neutrophils (PMN) play a central role in host defense against the neglected fungal infection paracoccidioidomycosis (PCM), which is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb). PCM is of major importance, especially in Latin America, and its treatment relies on the use of antifungal drugs. However, the course of treatment is lengthy, leading to side effects and even development of fungal resistance. The goal of the study was to use low-level laser therapy (LLLT) to stimulate PMN to fight Pb in vivo. Swiss mice with subcutaneous air pouches were inoculated with a virulent strain of Pb or fungal cell wall components (Zymosan), and then received LLLT (780 nm; 50 mW; 12.5 J/cm2; 30 seconds per point, giving a total energy of 0.5 J per point) on alternate days at two points on each hind leg. The aim was to reach the bone marrow in the femur with light. Non-irradiated animals were used as controls. The number and viability of the PMN that migrated to the inoculation site was assessed, as well as their ability to synthesize proteins, produce reactive oxygen species (ROS) and their fungicidal activity. The highly pure PMN populations obtained after 10 days of infection were also subsequently cultured in the presence of Pb for trials of protein production, evaluation of mitochondrial activity, ROS production and quantification of viable fungi growth. PMN from mice that received LLLT were more active metabolically, had higher fungicidal activity against Pb in vivo and also in vitro. The kinetics of neutrophil protein production also correlated with a more activated state. LLLT may be a safe and non-invasive approach to deal with PCM infection. PMID:25675431

Burger, Eva; Mendes, Ana Carolina S C; Bani, Giulia M A C; Brigagão, Maísa R P L; Santos, Gérsika B; Malaquias, Luiz Cosme C; Chavasco, Jorge Kleber; Verinaud, Liana M; de Camargo, Zoilo P; Hamblin, Michael R; Sperandio, Felipe F

2015-02-01

45

Biochemical Characterization of Paracoccidioides brasiliensis ?-1,3-Glucanase Agn1p, and Its Functionality by Heterologous Expression in Schizosaccharomyces pombe  

PubMed Central

?-1,3-Glucan is present as the outermost layer of the cell wall in the pathogenic yeastlike (Y) form of Paracoccidioides brasiliensis. Based on experimental evidence, this polysaccharide has been proposed as a fungal virulence factor. To degrade ?-1,3-glucan and allow remodeling of the cell wall, ?-1,3-glucanase is required. Therefore, the study of this enzyme, its encoding gene, and regulatory mechanisms, might be of interest to understand the morphogenesis and virulence process in this fungus. A single gene, orthologous to other fungal ?-1,3-glucanase genes, was identified in the Paracoccidioides genome, and labeled AGN1. Transcriptional levels of AGN1 and AGS1 (?-1,3-glucan synthase-encoding gene) increased sharply when the pathogenic Y phase was cultured in the presence of 5% horse serum, a reported booster for cell wall ?-1,3-glucan synthesis in this fungus. To study the biochemical properties of P. brasiliensis Agn1p, the enzyme was heterologously overexpressed, purified, and its activity profile determined by means of the degradation of carboxymethyl ?-1,3-glucan (SCMG, chemically modified from P. brasiliensis ?-1,3-glucan), used as a soluble substrate for the enzymatic reaction. Inhibition assays, thin layer chromatography and enzymatic reactions with alternative substrates (dextran, starch, chitin, laminarin and cellulose), showed that Agn1p displays an endolytic cut pattern and high specificity for SCMG. Complementation of a Schizosaccharomyces pombe agn1? strain with the P. brasiliensis AGN1 gene restored the wild type phenotype, indicating functionality of the gene, suggesting a possible role of Agn1p in the remodeling of P. brasiliensis Y phase cell wall. Based on amino acid sequence, P. brasiliensis Agn1p, groups within the family 71 of fungal glycoside hydrolases (GH-71), showing similar biochemical characteristics to other members of this family. Also based on amino acid sequence alignments, we propose a subdivision of fungal GH-71 into at least five groups, for which specific conserved sequences can be identified. PMID:23825576

Villalobos-Duno, Héctor; San-Blas, Gioconda; Paulinkevicius, Maryan; Sánchez-Martín, Yolanda; Nino-Vega, Gustavo

2013-01-01

46

Evidence of idiotypic modulation in the immune response to gp43, the major antigenic component of Paracoccidioides brasiliensis in both mice and humans  

PubMed Central

Paracoccidioidomycosis (PCM) is a systemic mycosis endemic in Latin America, with a high prevalence in Brazil, Argentina, Colombia and Venezuela. The aetiologic agent of disease is a thermal dimorphic fungus, Paracoccidioides brasiliensis. A glycoprotein of 43 000 D (gp43) is the major antigen of P. brasiliensis. Antibodies directed to this antigen are detected in the sera of all patients with PCM. Gp43 binds to laminin, thus participating in adhesion, invasion and pathogenesis of the fungus. As the role of antibodies in PCM is not fully understood, we decided to investigate the outcome of mice immunization with three distinct anti-gp43 MoAbs (17c, 8a and 24a) coupled with keyhole limpet haemocyanin (KLH). Results show not only the expected presence of anti-Id (AB2) antibodies in the sera of these animals but also a spontaneous and increasing amount of anti-anti-Id (AB3) antibodies after the third course of immunization. Hybridomas producing both AB2 and AB3 MoAbs were obtained using spleen cells from mice immunized with MoAb 17c. AB3 MoAbs were also obtained with spleen cells of mice immunized with MoAbs 8a and 24a. It was also shown that human PCM patients' sera with high titres of anti-gp43 antibodies generate anti-Id antibodies. These data suggest that the immune response to P. brasiliensis can be spontaneously modulated by the idiotypic network. PMID:9764601

Souza, A R; Gesztesi, J -L; Moraes, J Z; Cruz, C R B; Sato, J; Mariano, M; Lopes, J D

1998-01-01

47

Phylogenetic and evolutionary aspects of Paracoccidioides brasiliensis reveal a long coexistence with animal hosts that explain several biological features of the pathogen.  

PubMed

The habitat of the mycelial saprobic form of Paracoccidioides brasiliensis, which produces the infectious propagula, has not been determined and has proven difficult for mycologists to describe. The fungus has been rarely isolated from the environment, the disease has a prolonged latency period and no outbreaks have been reported. These facts have precluded the adoption of preventive measures to avoid infection. The confirmation of natural infections in nine-banded armadillos (Dasypus novemcinctus) with P. brasiliensis, in high frequency and wide geographic distribution, has opened new avenues for the study and understanding of its ecology. Armadillos belong to the order Xenarthra, which has existed in South America ever since the Paleocene Era (65 million years ago), when the South American subcontinent was still a detached land, before the consolidation of what is now known as the American continent. On the other hand, strong molecular evidence suggests that P. brasiliensis and other dimorphic pathogenic fungi--such as Blastomyces dermatitidis, Coccidioides immitis and Histoplasma capsulatum--belong to the family Onygenaceae sensu lato (order Onygenales, Ascomycota), which appeared around 150 million years ago. P. brasiliensis ecology and relation to its human host are probably linked to the fungal evolutionary past, especially its long coexistence with and adaptation to animal hosts other than Homo sapiens, of earlier origin. Instead of being a blind alley, the meaning of parasitism for dimorphic pathogenic fungi should be considered as an open two-way avenue, in which the fungus may return to the environment, therefore contributing to preserve its teleomorphic (sexual) and anamorphic (asexual) forms in a defined and protected natural habitat. PMID:16473563

Bagagli, Eduardo; Bosco, Sandra M G; Theodoro, Raquel Cordeiro; Franco, Marcello

2006-09-01

48

Transcriptomic reprogramming of genus Paracoccidioides in dimorphism and host niches.  

PubMed

The thermodimorphic fungi Paracoccidioides brasiliensis and Paracoccidioides lutzii are the etiologic agents of Paracoccidioidomycosis (PCM), the most important endemic systemic mycosis in Latin America. Paracoccidioides grows as saprophytic mycelia that produce infective conidia propagules, which are inhaled into the lungs where the fungus converts to the pathogenic yeast form. From the lungs, Paracoccidioides may disseminate through blood and lymphatics to several other organs and tissues. During the last decade we have witnessed the generation of a large amount of transcriptomic data regarding the events leading to the morphological transition and host niche adaptation. In this review we summarize those findings and discuss the consequence of gene expression plasticity in the persistence and survival of this pathogen. In addition, we discuss the future trends on the host-pathogen studies and how new molecular strategies, such as RNA-seq, dual RNA-seq and Chip-Seq can be powerful tools to improve our understanding on the pathobiology of this systemic mycosis in Latin America. PMID:24560614

Tavares, Aldo Henrique; Fernandes, Larissa; Bocca, Anamélia Lorenzetti; Silva-Pereira, Ildinete; Felipe, Maria Sueli

2014-02-18

49

Immunodiagnosis of Paracoccidioidomycosis due to Paracoccidioides brasiliensis Using a Latex Test: Detection of Specific Antibody Anti-gp43 and Specific Antigen gp43  

PubMed Central

Background Paracoccidioidomycosis (PCM) is a life-threatening systemic disease and is a neglected public health problem in many endemic regions of Latin America. Though several diagnostic methods are available, almost all of them present with some limitations. Method/Principle Findings A latex immunoassay using sensitized latex particles (SLPs) with gp43 antigen, the immunodominant antigen of Paracoccidioides brasiliensis, or the monoclonal antibody mAb17c (anti-gp43) was evaluated for antibody or antigen detection in sera, cerebrospinal fluid (CSF), and bronchoalveolar lavage (BAL) from patients with PCM due to P. brasiliensis. The gp43-SLPs performed optimally to detect specific antibodies with high levels of sensitivity (98.46%, 95% CI 91.7–100.0), specificity (93.94%, 95% CI 87.3–97.7), and positive (91.4%) and negative (98.9%) predictive values. In addition, we propose the use of mAb17c-SLPs to detect circulating gp43, which would be particularly important in patients with immune deficiencies who fail to produce normal levels of immunoglobulins, achieving good levels of sensitivity (96.92%, 95% CI 89.3–99.6), specificity (88.89%, 95% CI 81.0–94.3), and positive (85.1%) and negative (97.8%) predictive values. Very good agreement between latex tests and double immune diffusion was observed for gp43-SLPs (k = 0.924) and mAb17c-SLPs (k = 0.850), which reinforces the usefulness of our tests for the rapid diagnosis of PCM in less than 10 minutes. Minor cross-reactivity occurred with sera from patients with other fungal infections. We successfully detected antigens and antibodies from CSF and BAL samples. In addition, the latex test was useful for monitoring PCM patients receiving therapy. Conclusions/Significance The high diagnostic accuracy, low cost, reduced assay time, and simplicity of this new latex test offer the potential to be commercialized and makes it an attractive diagnostic assay for use not only in clinics and medical mycology laboratories, but mainly in remote locations with limited laboratory infrastructure and/or minimally trained community health workers. PMID:25679976

dos Santos, Priscila Oliveira; Rodrigues, Anderson Messias; Fernandes, Geisa Ferreira; da Silva, Silvia Helena Marques; Burger, Eva; de Camargo, Zoilo Pires

2015-01-01

50

TLR-4 cooperates with Dectin-1 and mannose receptor to expand Th17 and Tc17 cells induced by Paracoccidioides brasiliensis stimulated dendritic cells  

PubMed Central

The concomitant use of diverse pattern recognition receptors (PRRs) by innate immune cells can result in synergistic or inhibitory activities that profoundly influence anti-microbial immunity. Dectin-1 and the mannose receptor (MR) are C-type lectin receptors (CLRs) previously reported to cooperate with toll-like receptors (TLRs) signaling in the initial inflammatory response and in the induction of adaptive Th17 and Tc17 immunity mediated by CD4+ and CD8+ T cells, respectively. The protective immunity against paracoccidioidomycosis, the most prevalent fungal infection of Latin America, was previously shown to be influenced by these T cell subsets motivating us to study the contribution of TLRs, Dectin-1, and MR to the development of Th17/Tc17 immunity. First, curdlan a specific Dectin-1 agonist was used to characterize the influence of this receptor in the proliferative response and Th17/Tc17 differentiation of naïve lymphocytes induced by Paracoccidioides brasiliensis activated dendritic cells (DCs) from C57BL/6 mice. Then, wild type (WT), Dectin-1–/–, TLR-2–/–, and TLR-4–/– DCs treated or untreated with anti-Dectin-1 and anti-MR antibodies were used to investigate the contribution of these receptors in lymphocyte activation and differentiation. We verified that curdlan induces an enhanced lymphocyte proliferation and development of IL-17 producing CD4+ and CD8+ T cells. In addition, treatment of WT, TLR-2–/–, and TLR-4–/– DCs by anti-Dectin-1 antibodies or antigen presentation by Dectin-1–/– DCs led to decreased lymphoproliferation and impaired Th17 and Tc17 expansion. These responses were also inhibited by anti-MR treatment of DCs, but a synergistic action on Th17/Tc17 differentiation was mediated by TLR-4 and MR. Taken together, our results indicate that diverse TLRs and CLRs are involved in the induction of lymphocyte proliferation and Th17/Tc17 differentiation mediated by P. brasiliensis activated DCs, but a synergist action was restricted to Dectin-1, TLR-4, and MR.

Loures, Flávio V.; Araújo, Eliseu F.; Feriotti, Claudia; Bazan, Silvia B.; Calich, Vera L. G.

2015-01-01

51

In Vitro Antifungal Activity of Micafungin (FK463) against Dimorphic Fungi: Comparison of YeastLike and Mycelial Forms  

Microsoft Academic Search

The characteristics of in vitro micafungin (FK463) antifungal activity against six species of dimorphic fungi were investigated in accordance with the NCCLS M27-A microdilution methods. MICs of micafungin, ampho- tericin B, itraconazole, and fluconazole for Histoplasma capsulatum var. capsulatum, Blastomyces dermatitidis, Paracoccidioides brasiliensis, Penicillium marneffei, and Sporothrix schenckii were determined both for the yeast- like form and mycelial form. Coccidioides

Toru Nakai; Jun Uno; Fumiaki Ikeda; Shuichi Tawara; Kazuko Nishimura; Makoto Miyaji

2003-01-01

52

Pseudozyma brasiliensis sp. nov., a xylanolytic, ustilaginomycetous yeast species isolated from an insect pest of sugarcane roots.  

PubMed

A novel ustilaginomycetous yeast isolated from the intestinal tract of an insect pest of sugarcane roots in Ribeirão Preto, São Paulo State, Brazil, represents a novel species of the genus Pseudozyma based on molecular analyses of the D1/D2 rDNA large subunit and the internal transcribed spacer (ITS1+ITS2) regions. The name Pseudozyma brasiliensis sp. nov. is proposed for this species, with GHG001(T) (?=?CBS 13268(T)?=?UFMG-CM-Y307(T)) as the type strain. P. brasiliensis sp. nov. is a sister species of Pseudozyma vetiver, originally isolated from leaves of vetiver grass and sugarcane in Thailand. P. brasiliensis sp. nov. is able to grow well with xylan as the sole carbon source and produces high levels of an endo-1,4-xylanase that has a higher specific activity in comparison with other eukaryotic xylanases. This enzyme has a variety of industrial applications, indicating the great biotechnological potential of P. brasiliensis. PMID:24682702

Oliveira, Juliana Velasco de Castro; Borges, Thuanny A; Corrêa dos Santos, Renato Augusto; Freitas, Larissa F D; Rosa, Carlos Augusto; Goldman, Gustavo Henrique; Riaño-Pachón, Diego Mauricio

2014-06-01

53

Genus Paracoccidioides: Species Recognition and Biogeographic Aspects  

PubMed Central

Background Paracoccidioidomycosis is a systemic mycosis caused by Paracoccidioides brasiliensis (species S1, PS2, PS3), and Paracoccidioides lutzii. This work aimed to differentiate species within the genus Paracoccidioides, without applying multilocus sequencing, as well as to obtain knowledge of the possible speciation processes. Methodology/Principal Findings Single nucleotide polymorphism analysis on GP43, ARF and PRP8 intein genes successfully distinguished isolates into four different species. Morphological evaluation indicated that elongated conidia were observed exclusively in P. lutzii isolates, while all other species (S1, PS2 and PS3) were indistinguishable. To evaluate the biogeographic events that led to the current geographic distribution of Paracoccidioides species and their sister species, Nested Clade and Likelihood Analysis of Geographic Range Evolution (LAGRANGE) analyses were applied. The radiation of Paracoccidioides started in northwest South America, around 11–32 million years ago, as calculated on the basis of ARF substitution rate, in the BEAST program. Vicariance was responsible for the divergence among S1, PS2 and P. lutzii and a recent dispersal generated the PS3 species, restricted to Colombia. Taking into account the ancestral areas revealed by the LAGRANGE analysis and the major geographic distribution of L. loboi in the Amazon basin, a region strongly affected by the Andes uplift and marine incursions in the Cenozoic era, we also speculate about the effect of these geological events on the vicariance between Paracoccidioides and L. loboi. Conclusions/Significance The use of at least 3 SNPs, but not morphological criteria, as markers allows us to distinguish among the four cryptic species of the genus Paracoccidioides. The work also presents a biogeographic study speculating on how these species might have diverged in South America, thus contributing to elucidating evolutionary aspects of the genus Paracoccidioides. PMID:22666382

Theodoro, Raquel Cordeiro; Teixeira, Marcus de Melo; Felipe, Maria Sueli Soares; Paduan, Karina dos Santos; Ribolla, Paulo Martins; San-Blas, Gioconda; Bagagli, Eduardo

2012-01-01

54

A Morphological and Cytochemical Study of the Interaction between Paracoccidiodes brasiliensis and Neutrophils  

NASA Astrophysics Data System (ADS)

Paracoccidioidomycosis is a systemic granulomatous disease caused by the dimorphic fungus Paracoccidioides brasiliensis. It is the most prevalent systemic mycosis of Latin America and 80% of the reported cases are from Brazil. Because of the great number of neutrophils found in the P. brasiliensis granuloma, studies have been done to evaluate the role of these cells during the development of the infection. Scanning and transmission electron microscopy of thin sections showed that the neutrophils ingest yeast cells through a typical phagocytic process with the formation of pseudopodes. The pseudopodes even disrupt the connection established between the mother and the bud cells. Neutrophils also associate to each other, forming a kind of extracellular vacuole where large yeast cells are encapsulated. Cytochemical studies showed that once P. brasiliensis attaches to the neutrophil surface, it triggers a respiratory burst with release of oxygen-derived products. Attachment also triggers neutrophils' degranulation, with release of endogenous peroxidase localized in cytoplasmic granules. Together, these processes lead to killing of both ingested and extracellular P. brasiliensis.

Dias, Maria Fernanda R. G.; Filgueira, Absalom L.; de Souza, Wanderley

2004-04-01

55

Identification and characterization of Tc1\\/mariner-like DNA transposons in genomes of the pathogenic fungi of the Paracoccidioides species complex  

Microsoft Academic Search

BACKGROUND: Paracoccidioides brasiliensis (Eukaryota, Fungi, Ascomycota) is a thermodimorphic fungus, the etiological agent of paracoccidioidomycosis, the most important systemic mycoses in Latin America. Three isolates corresponding to distinct phylogenetic lineages of the Paracoccidioides species complex had their genomes sequenced. In this study the identification and characterization of class II transposable elements in the genomes of these fungi was carried out.

Marjorie M Marini; Tamiris Zanforlin; Patrícia C Santos; Roberto RM Barros; Rosana Puccia; Maria SS Felipe; Marcelo Brigido; Célia MA Soares; Jerônimo C Ruiz; José F Silveira; Patrícia S Cisalpino

2010-01-01

56

Paracoccidioides brasilinsis-Induced Migration of Dendritic Cells and Subsequent T-Cell Activation in the Lung-Draining Lymph Nodes  

Microsoft Academic Search

Paracoccidioidomycosis is a mycotic disease caused by a dimorphic fungus, Paracoccidioides brasiliensis (Pb), that starts with inhalation of the fungus; thus, lung cells such as DC are part of the first line of defense against this microorganism. Migration of DC to the lymph nodes is the first step in initiating T cell responses. The mechanisms involved in resistance to Pb

Suelen Silvana dos Santos; Karen Spadari Ferreira; Sandro Rogerio Almeida

2011-01-01

57

The diversity and extracellular enzymatic activities of yeasts isolated from water tanks of Vriesea minarum, an endangered bromeliad species in Brazil, and the description of Occultifur brasiliensis f.a., sp. nov.  

PubMed

The diversity of yeast species collected from the bromeliad tanks of Vriesea minarum, an endangered bromeliad species, and their ability to produce extracellular enzymes were studied. Water samples were collected from 30 tanks of bromeliads living in a rupestrian field site located at Serrada Piedade, Minas Gerais state, Brazil, during both the dry and rainy seasons. Thirty-six species were isolated, representing 22 basidiomycetous and 14 ascomycetous species. Occultifur sp., Cryptococcus podzolicus and Cryptococcus sp. 1 were the prevalent basidiomycetous species. The yeast-like fungus from the order Myriangiales, Candida silvae and Aureobasidium pullulans were the most frequent ascomycetous species. The diversity of the yeast communities obtained between seasons was not significantly different, but the yeast composition per bromeliad was different between seasons. These results suggest that there is significant spatial heterogeneity in the composition of populations of the yeast communities within bromeliad tanks, independent of the season. Among the 352 yeast isolates tested, 282 showed at least one enzymatic activity. Protease activity was the most widely expressed extracellular enzymatic activity, followed by xylanase, amylase, pectinase and cellulase activities. These enzymes may increase the carbon and nitrogen availability for the microbial food web in the bromeliad tank of V. minarum. Sequence analyses revealed the existence of 10 new species, indicating that bromeliad tanks are important sources of new yeasts. The novel species Occultifur brasiliensis, f.a., sp. nov., is proposed to accommodate the most frequently isolated yeast associated with V. minarum. The type strain of O. brasiliensis, f.a., sp. nov. is UFMG-CM-Y375(T) (= CBS 12687(T)). The Mycobank number is MB 809816. PMID:25515414

Gomes, Fátima C O; Safar, Silvana V B; Marques, Andrea R; Medeiros, Adriana O; Santos, Ana Raquel O; Carvalho, Cláudia; Lachance, Marc-André; Sampaio, José Paulo; Rosa, Carlos A

2015-02-01

58

Predicting copper-, iron-, and zinc-binding proteins in pathogenic species of the Paracoccidioides genus  

PubMed Central

Approximately one-third of all proteins have been estimated to contain at least one metal cofactor, and these proteins are referred to as metalloproteins. These represent one of the most diverse classes of proteins, containing metal ions that bind to specific sites to perform catalytic, regulatory and structural functions. Bioinformatic tools have been developed to predict metalloproteins encoded by an organism based only on its genome sequence. Its function and the type of metal binder can also be predicted via a bioinformatics approach. Paracoccidioides complex includes termodimorphic pathogenic fungi that are found as saprobic mycelia in the environment and as yeast, the parasitic form, in host tissues. They are the etiologic agents of Paracoccidioidomycosis, a prevalent systemic mycosis in Latin America. Many metalloproteins are important for the virulence of several pathogenic microorganisms. Accordingly, the present work aimed to predict the copper, iron and zinc proteins encoded by the genomes of three phylogenetic species of Paracoccidioides (Pb01, Pb03, and Pb18). The metalloproteins were identified using bioinformatics approaches based on structure, annotation and domains. Cu-, Fe-, and Zn-binding proteins represent 7% of the total proteins encoded by Paracoccidioides spp. genomes. Zinc proteins were the most abundant metalloproteins, representing 5.7% of the fungus proteome, whereas copper and iron proteins represent 0.3 and 1.2%, respectively. Functional classification revealed that metalloproteins are related to many cellular processes. Furthermore, it was observed that many of these metalloproteins serve as virulence factors in the biology of the fungus. Thus, it is concluded that the Cu, Fe, and Zn metalloproteomes of the Paracoccidioides spp. are of the utmost importance for the biology and virulence of these particular human pathogens. PMID:25620964

Tristão, Gabriel B.; Assunção, Leandro do Prado; dos Santos, Luiz Paulo A.; Borges, Clayton L.; Silva-Bailão, Mirelle Garcia; Soares, Célia M. de Almeida; Cavallaro, Gabriele; Bailão, Alexandre M.

2015-01-01

59

Predicting copper-, iron-, and zinc-binding proteins in pathogenic species of the Paracoccidioides genus.  

PubMed

Approximately one-third of all proteins have been estimated to contain at least one metal cofactor, and these proteins are referred to as metalloproteins. These represent one of the most diverse classes of proteins, containing metal ions that bind to specific sites to perform catalytic, regulatory and structural functions. Bioinformatic tools have been developed to predict metalloproteins encoded by an organism based only on its genome sequence. Its function and the type of metal binder can also be predicted via a bioinformatics approach. Paracoccidioides complex includes termodimorphic pathogenic fungi that are found as saprobic mycelia in the environment and as yeast, the parasitic form, in host tissues. They are the etiologic agents of Paracoccidioidomycosis, a prevalent systemic mycosis in Latin America. Many metalloproteins are important for the virulence of several pathogenic microorganisms. Accordingly, the present work aimed to predict the copper, iron and zinc proteins encoded by the genomes of three phylogenetic species of Paracoccidioides (Pb01, Pb03, and Pb18). The metalloproteins were identified using bioinformatics approaches based on structure, annotation and domains. Cu-, Fe-, and Zn-binding proteins represent 7% of the total proteins encoded by Paracoccidioides spp. genomes. Zinc proteins were the most abundant metalloproteins, representing 5.7% of the fungus proteome, whereas copper and iron proteins represent 0.3 and 1.2%, respectively. Functional classification revealed that metalloproteins are related to many cellular processes. Furthermore, it was observed that many of these metalloproteins serve as virulence factors in the biology of the fungus. Thus, it is concluded that the Cu, Fe, and Zn metalloproteomes of the Paracoccidioides spp. are of the utmost importance for the biology and virulence of these particular human pathogens. PMID:25620964

Tristão, Gabriel B; Assunção, Leandro do Prado; Dos Santos, Luiz Paulo A; Borges, Clayton L; Silva-Bailão, Mirelle Garcia; Soares, Célia M de Almeida; Cavallaro, Gabriele; Bailão, Alexandre M

2014-01-01

60

Transcriptional profile of Paracoccidioides induced by oenothein B, a potential antifungal agent from the Brazilian Cerrado plant Eugenia uniflora  

PubMed Central

Background The compound oenothein B (OenB), which is isolated from the leaves of Eugenia uniflora, a Brazilian Cerrado plant, interferes with Paracoccidioides yeast cell morphology and inhibits 1,3-?-D-glucan synthase (PbFKS1) transcript accumulation, which is involved in cell wall synthesis. In this work we examined the gene expression changes in Paracoccidioides yeast cells following OenB treatment in order to investigate the adaptive cellular responses to drug stress. Results We constructed differential gene expression libraries using Representational Difference Analysis (RDA) of Paracoccidioides yeast cells treated with OenB for 90 and 180 min. Treatment for 90 min resulted in the identification of 463 up-regulated expressed sequences tags (ESTs) and 104 down-regulated ESTs. For the 180 min treatment 301 up-regulated ESTs and 143 down-regulated were identified. Genes involved in the cell wall biosynthesis, such as GLN1, KRE6 and FKS1, were found to be regulated by OenB. Infection experiments in macrophages corroborated the in vitro results. Fluorescence microscopy showed increased levels of chitin in cells treated with OenB. The carbohydrate polymer content of the cell wall of the fungus was also evaluated, and the results corroborated with the transcriptional data. Several other genes, such as those involved in a variety of important cellular processes (i.e., membrane maintenance, stress and virulence) were found to be up-regulated in response to OenB treatment. Conclusions The exposure of Paracoccidioides to OenB resulted in a complex altered gene expression profile. Some of the changes may represent specific adaptive responses to this compound in this important pathogenic fungus. PMID:24119145

2013-01-01

61

Inhibition of Paracoccidioides lutzii Pb01 Isocitrate Lyase by the Natural Compound Argentilactone and Its Semi-Synthetic Derivatives  

PubMed Central

The dimorphic fungus Paracoccidioides spp. is responsible for paracoccidioidomycosis, the most prevalent systemic mycosis in Latin America, causing serious public health problems. Adequate treatment of mycotic infections is difficult, since fungi are eukaryotic organisms with a structure and metabolism similar to those of eukaryotic hosts. In this way, specific fungus targets have become important to search of new antifungal compound. The role of the glyoxylate cycle and its enzymes in microbial virulence has been reported in many fungal pathogens, including Paracoccidioides spp. Here, we show the action of argentilactone and its semi-synthetic derivative reduced argentilactone on recombinant and native isocitrate lyase from Paracoccidioides lutzii Pb01 (PbICL) in the presence of different carbon sources, acetate and glucose. Additionally, argentilactone and its semi-synthetic derivative reduced argentilactone exhibited relevant inhibitory activity against P. lutzii Pb01 yeast cells and dose-dependently influenced the transition from the mycelium to yeast phase. The other oxygenated derivatives tested, epoxy argentilactone and diol argentilactone-, did not show inhibitory action on the fungus. The results were supported by in silico experiments. PMID:24752170

do Prado, Renata Silva; Alves, Ricardo Justino; de Oliveira, Cecília Maria Alves; Kato, Lucília; da Silva, Roosevelt Alves; Quintino, Guilherme Oliveira; do Desterro Cunha, Silvio; de Almeida Soares, Célia Maria; Pereira, Maristela

2014-01-01

62

New Paracoccidioides brasiliensis isolate reveals unexpected genomic variability in this human pathogen  

E-print Network

Brasi´lia, Brazil c Universidade Federal de Goia´s, Brazil d Corporacio´n para Investigaciones Biolo, Michigan State University, Michigan, USA f University of California, Berkeley, CA, USA Received 9 November

63

Hemoglobin Uptake by Paracoccidioides spp. Is Receptor-Mediated  

PubMed Central

Iron is essential for the proliferation of fungal pathogens during infection. The availability of iron is limited due to its association with host proteins. Fungal pathogens have evolved different mechanisms to acquire iron from host; however, little is known regarding how Paracoccidioides species incorporate and metabolize this ion. In this work, host iron sources that are used by Paracoccidioides spp. were investigated. Robust fungal growth in the presence of the iron-containing molecules hemin and hemoglobin was observed. Paracoccidioides spp. present hemolytic activity and have the ability to internalize a protoporphyrin ring. Using real-time PCR and nanoUPLC-MSE proteomic approaches, fungal growth in the presence of hemoglobin was shown to result in the positive regulation of transcripts that encode putative hemoglobin receptors, in addition to the induction of proteins that are required for amino acid metabolism and vacuolar protein degradation. In fact, one hemoglobin receptor ortholog, Rbt5, was identified as a surface GPI-anchored protein that recognized hemin, protoporphyrin and hemoglobin in vitro. Antisense RNA technology and Agrobacterium tumefaciens-mediated transformation were used to generate mitotically stable Pbrbt5 mutants. The knockdown strain had a lower survival inside macrophages and in mouse spleen when compared with the parental strain, which suggested that Rbt5 could act as a virulence factor. In summary, our data indicate that Paracoccidioides spp. can use hemoglobin as an iron source most likely through receptor-mediated pathways that might be relevant for pathogenic mechanisms. PMID:24831516

Bailão, Elisa Flávia Luiz Cardoso; Parente, Juliana Alves; Pigosso, Laurine Lacerda; de Castro, Kelly Pacheco; Fonseca, Fernanda Lopes; Silva-Bailão, Mirelle Garcia; Báo, Sônia Nair; Bailão, Alexandre Melo; Rodrigues, Marcio L.; Hernandez, Orville; McEwen, Juan G.; Soares, Célia Maria de Almeida

2014-01-01

64

Mitochondrial PCR-RFLP Assay to Distinguish Triatoma brasiliensis macromelasoma from Triatoma brasiliensis brasiliensis Subspecies (Hemiptera: Reduviidae).  

PubMed

Triatoma brasiliensis sensu lato (s.l.), the main vector of Chagas disease in northeastern Brazil, is a species complex comprising four species, one with two subspecies (T. brasiliensis brasiliensis, T. brasiliensis macromelasoma, T. juazeirensis, T. sherlocki, and T. melanica), and each taxon displaying distinct ecological requirements. In order to evaluate the genetic relationships among nine T. brasiliensis s.l. populations from northeastern Brazil, we analyzed their mitochondrial cytochrome c oxidase subunit 1 sequences and suggested a PCR-RFLP assay to distinguish between T. b. macromelasoma and T. b. brasiliensis subspecies. All the specimens were morphologically identified as T. b. brasiliensis. The resulting phylogenies identified two major clades that are congruent with the geographical populations studied. Based on collection sites and in accordance with type-location, one clade was identified as the subspecies T. b. macromelasoma. The second clade grouped T. b. brasiliensis populations. Restriction endonuclease sites were observed in the sequences and used in PCR-RFLP assays, producing distinct fingerprints for T. b. macromelasoma and T. b. brasiliensis populations. The results suggest that these are different species and that gene flow occurs only among T. b. brasiliensis populations, possibly associated with human activity in the area. PMID:24454408

Vendrami, Daniel Pagotto; Ceretti-Junior, Walter; Obara, Marcos Takashi; Marrelli, Mauro Toledo

2013-01-01

65

Hydroxamate Production as a High Affinity Iron Acquisition Mechanism in Paracoccidioides Spp  

PubMed Central

Iron is a micronutrient required by almost all living organisms, including fungi. Although this metal is abundant, its bioavailability is low either in aerobic environments or within mammalian hosts. As a consequence, pathogenic microorganisms evolved high affinity iron acquisition mechanisms which include the production and uptake of siderophores. Here we investigated the utilization of these molecules by species of the Paracoccidioides genus, the causative agents of a systemic mycosis. It was demonstrated that iron starvation induces the expression of Paracoccidioides ortholog genes for siderophore biosynthesis and transport. Reversed-phase HPLC analysis revealed that the fungus produces and secretes coprogen B, which generates dimerumic acid as a breakdown product. Ferricrocin and ferrichrome C were detected in Paracoccidioides as the intracellular produced siderophores. Moreover, the fungus is also able to grow in presence of siderophores as the only iron sources, demonstrating that beyond producing, Paracoccidioides is also able to utilize siderophores for growth, including the xenosiderophore ferrioxamine. Exposure to exogenous ferrioxamine and dimerumic acid increased fungus survival during co-cultivation with macrophages indicating that these molecules play a role during host-pathogen interaction. Furthermore, cross-feeding experiments revealed that Paracoccidioides siderophores promotes growth of Aspergillus nidulans strain unable to produce these iron chelators. Together, these data denote that synthesis and utilization of siderophores is a mechanism used by Paracoccidioides to surpass iron limitation. As iron paucity is found within the host, siderophore production may be related to fungus pathogenicity. PMID:25157575

Silva-Bailão, Mirelle Garcia; Bailão, Elisa Flávia Luiz Cardoso; Lechner, Beatrix Elisabeth; Gauthier, Gregory M.; Lindner, Herbert; Bailão, Alexandre Melo; Haas, Hubertus; de Almeida Soares, Célia Maria

2014-01-01

66

Cytotaxonomy of the Brasiliensis subcomplex and the Triatoma brasiliensis complex (Hemiptera: Reduviidae: Triatominae).  

PubMed

We analyzed the classical cytotaxonomy of the Brasiliensis subcomplex (Triatoma brasiliensis Neiva, T. juazeirensis Costa & Felix, T. melanica Costa, Argolo & Felix, T. melanocephala Neiva & Pinto, T. petrochiae Pinto & Barreto, T. lenti Sherlock & Serafim, T. sherlocki Papa, Jurberg, Carcavallo, Cerqueira & Barata, T. tibiamaculata Pinto and T. vitticeps Stal) and the T. brasiliensis complex (T. b. brasiliensis, T. b. macromelasoma Neiva & Lent, T. juazeirensis, T. melanica and T. sherlocki). The five members of the T. brasiliensis complex share the same cytogenetic characteristics. Merely T. sherlocki show differences in spermatids, which confirms the status of more differentiated member of the complex. T. lenti also presented the same cytogenetic characteristics described for the species of the T. brasiliensis complex, which supports possible grouping of the species as sixth member of the complex, although further analysis as molecular and experimental crosses are needed to corroborate this hypothesis. T. petrochiae, T. vitticeps, T. tibiamaculata and T. melanocephala presented one or more characteristics that allow questioning grouping in the proposed Brasiliensis subcomplex. Thus, we suggested that Brasiliensis subcomplex and T. brasiliensis complex should be constituted by the same triatomines (T. b. brasiliensis, T. b. macromelasoma, T. juazeirensis, T. melanica and T. sherlocki). However, we draw attention to T. lenti and suggest that although new analyzes should be performed, possibly this species is the sixth member of the T. brasiliensis complex.  PMID:25081800

Alevi, Kaio C C; Rosa, João A; Azeredo-Oliveira, Maria Tercília V

2014-01-01

67

Cloning and characterisation of JAZ gene family in Hevea brasiliensis.  

PubMed

Mechanical wounding or treatment with exogenous jasmonates (JA) induces differentiation of the laticifer in Hevea brasiliensis. JA is a key signal for latex biosynthesis and wounding response in the rubber tree. Identification of JAZ (jasmonate ZIM-domain) family of proteins that repress JA responses has facilitated rapid progress in understanding how this lipid-derived hormone controls gene expression and related physiological processes in plants. In this work, the full-length cDNAs of six JAZ genes were cloned from H. brasiliensis (termed HbJAZ). These HbJAZ have different lengths and sequence diversity, but all of them contain Jas and ZIM domains, and two of them contain an ERF-associated amphiphilic repression (EAR) motif in the N-terminal. Real-time RT-PCR analyses revealed that HbJAZ have different expression patterns and tissue specificity. Four HbJAZ were up-regulated, one was down-regulated, while two were less effected by rubber tapping treatment, suggesting that they might play distinct roles in the wounding response. A yeast two-hybrid assay revealed that HbJAZ proteins interact with each other to form homologous or heterogeneous dimer complexes, indicating that the HbJAZ proteins may expand their function through diverse JAZ-JAZ interactions. This work lays a foundation for identification of the JA signalling pathway and molecular mechanisms of latex biosynthesis in rubber trees. PMID:25399518

Hong, H; Xiao, H; Yuan, H; Zhai, J; Huang, X

2015-05-01

68

Paracoccidoides brasiliensis 30 kDa adhesin: identification as a 14-3-3 protein, cloning and subcellular localization in infection models.  

PubMed

Paracoccidoides brasiliensis adhesion to lung epithelial cells is considered an essential event for the establishment of infection and different proteins participate in this process. One of these proteins is a 30 kDa adhesin, pI 4.9 that was described as a laminin ligand in previous studies, and it was more highly expressed in more virulent P. brasiliensis isolates. This protein may contribute to the virulence of this important fungal pathogen. Using Edman degradation and mass spectrometry analysis, this 30 kDa adhesin was identified as a 14-3-3 protein. These proteins are a conserved group of small acidic proteins involved in a variety of processes in eukaryotic organisms. However, the exact function of these proteins in some processes remains unknown. Thus, the goal of the present study was to characterize the role of this protein during the interaction between the fungus and its host. To achieve this goal, we cloned, expressed the 14-3-3 protein in a heterologous system and determined its subcellular localization in in vitro and in vivo infection models. Immunocytochemical analysis revealed the ubiquitous distribution of this protein in the yeast form of P. brasiliensis, with some concentration in the cytoplasm. Additionally, this 14-3-3 protein was also present in P. brasiliensis cells at the sites of infection in C57BL/6 mice intratracheally infected with P. brasiliensis yeast cells for 72 h (acute infections) and 30 days (chronic infection). An apparent increase in the levels of the 14-3-3 protein in the cell wall of the fungus was also noted during the interaction between P. brasiliensis and A549 cells, suggesting that this protein may be involved in host-parasite interactions, since inhibition assays with the protein and this antibody decreased P. brasiliensis adhesion to A549 epithelial cells. Our data may lead to a better understanding of P. brasiliensis interactions with host tissues and paracoccidioidomycosis pathogenesis. PMID:23638109

da Silva, Julhiany de Fatima; de Oliveira, Haroldo César; Marcos, Caroline Maria; da Silva, Rosângela Aparecida Moraes; da Costa, Tania Alves; Calich, Vera Lucia García; Almeida, Ana Marisa Fusco; Mendes-Giannini, Maria José Soares

2013-01-01

69

Nocardia brasiliensis vertebral osteomyelitis and epidural abscess.  

PubMed

Nocardia species exist in the environment as a saprophyte; it is found worldwide in soil and decaying plant matter. They often infect patients with underlying immune compromise, pulmonary disease or history of trauma or surgery. The diagnosis of nocardiosis can be easily missed as it mimics many other granulomatous and neoplastic disease. We report a 69-year-old man who presented with chronic back pain and paraparesis. He was found to have Nocardial brasiliensis vertebral osteomyelitis and epidural abscess. Laminectomy and epidural wash out was performed but with no neurological recovery. This is the second reported case of N brasiliensis vertebral osteomyelitis in the literature. PMID:23585503

Johnson, Philip; Ammar, Hussam

2013-01-01

70

Nocardia brasiliensis-associated femorotibial osteomyelitis.  

PubMed

We report a case of femorotibial osteomyelitis due to Nocardia brasiliensis. Nocardia spp are a rare cause of bone infections, and the majority of such cases are associated with the spine. This type of osteomyelitis is uncommon, and in the immunocompetent host, is more often related to a chronic evolution following direct inoculation of the microorganism. PMID:24362018

Vanegas, Samuel; Franco-Cendejas, Rafael; Cicero, Antonio; López-Jácome, Esaú; Colin, Claudia; Hernández, Melissa

2014-03-01

71

The multifaceted roles of metabolic enzymes in the Paracoccidioides species complex  

PubMed Central

Paracoccidioides species are dimorphic fungi and are the etiologic agents of paracoccidioidomycosis, which is a serious disease that involves multiple organs. The many tissues colonized by this fungus suggest a variety of surface molecules involved in adhesion. A surprising finding is that most enzymes in the glycolytic pathway, tricarboxylic acid (TCA) cycle and glyoxylate cycle in Paracoccidioides spp. have adhesive properties that aid in interacting with the host extracellular matrix and thus act as ‘moonlighting’ proteins. Moonlighting proteins have multiple functions, which adds a dimension to cellular complexity and benefit cells in several ways. This phenomenon occurs in both eukaryotes and prokaryotes. For example, moonlighting proteins from the glycolytic pathway or TCA cycle can play a role in bacterial pathogenesis by either acting as proteins secreted in a conventional pathway and/or as cell surface components that facilitate adhesion or adherence. This review outlines the multifunctionality exhibited by many Paracoccidioides spp. enzymes, including aconitase, aldolase, glyceraldehyde-3-phosphate dehydrogenase, isocitrate lyase, malate synthase, triose phosphate isomerase, fumarase, and enolase. We discuss the roles that moonlighting activities play in the virulence characteristics of this fungus and several other human pathogens during their interactions with the host. PMID:25566229

Marcos, Caroline M.; de Oliveira, Haroldo C.; da Silva, Julhiany de F.; Assato, Patrícia A.; Fusco-Almeida, Ana M.; Mendes-Giannini, Maria J. S.

2014-01-01

72

Miltefosine is active against Sporothrix brasiliensis isolates with in vitro low susceptibility to amphotericin B or itraconazole.  

PubMed

Sporotrichosis is a common mycosis caused by dimorphic fungi from the Sporothrix schenckii complex. In recent years, sporotrichosis incidence rates have increased in the Brazilian state of Rio de Janeiro, where Sporothrix brasiliensis is the species more frequently isolated from patients. The standard antifungals itraconazole and amphotericin B are recommended as first-line therapy for cutaneous/lymphocutaneous and disseminated sporotrichosis, respectively, although decreased sensitivity to these drugs in vitro was reported for clinical isolates of S. brasiliensis. Here, we evaluated the activity of the phospholipid analogue miltefosine - already in clinical use against leishmaniasis - towards the pathogenic yeast form of S. brasiliensis isolates with low sensitivity to itraconazole or amphotericin B in vitro. Miltefosine had fungicidal activity, with minimum inhibitory concentration (MIC) values of 1-2 µg ml(-1). Miltefosine exposure led to loss of plasma membrane integrity, and transmission electron microscopy (TEM) analysis revealed a decrease in cytoplasmic electron density, alterations in the thickness of cell wall layers and accumulation of an electron-dense material in the cell wall. Flow cytometry analysis using an anti-melanin antibody revealed an increase in cell wall melanin in yeasts treated with miltefosine, when compared with control cells. The cytotoxicity of miltefosine was comparable to those of amphotericin B, but miltefosine showed a higher selectivity index towards the fungus. Our results suggest that miltefosine could be an effective alternative for the treatment of S. brasiliensis sporotrichosis, when standard treatment fails. Nevertheless, in vivo studies are required to confirm the antifungal potential of miltefosine for the treatment of sporotrichosis. PMID:25681323

Borba-Santos, Luana Pereira; Gagini, Thalita; Ishida, Kelly; de Souza, Wanderley; Rozental, Sonia

2015-04-01

73

Genetic Diversity of Pectobacterium carotovorum subsp. brasiliensis Isolated in Korea  

PubMed Central

The plant pathogenic bacterial genus Pectobacteirum consists of heterogeneous strains. The P. carotovorum species is a complex strain showing divergent characteristics, and a new subspecies named P. carotovorum subsp. brasiliensis has been identified recently. In this paper, we re-identified the P. carotovorum subsp. brasiliensis isolates from those classified under the subspecies carotovorum and newly isolated P. carotovorum subsp. brasiliensis strains. All isolates were able to produce plant cell-wall degrading enzymes such as pectate lyase, polygalacturonase, cellulase and protease. We used genetic and biochemical methods to examine the diversity of P. carotovorum subsp. brasiliensis isolates, and found genetic diversity within the brasiliensis subsp. isolates in Korea. The restriction fragment length polymorphism analysis based on the recA gene revealed a unique pattern for the brasiliensis subspecies. The Korean brasiliensis subsp. isolates were divided into four clades based on pulsed-field gel electrophoresis. However, correlations between clades and isolated hosts or year could not be found, suggesting that diverse brasiliensis subsp. isolates existed. PMID:25288994

Lee, Dong Hwan; Kim, Jin-Beom; Lim, Jeong-A; Han, Sang-Wook; Heu, Sunggi

2014-01-01

74

Spoilage yeasts.  

PubMed

Yeasts are best known for their beneficial contributions to society, and the literature abounds with discussions of their role in the fermentation of alcoholic beverages, bread, and other products. Yeasts also cause spoilage, but, with a few exceptions, this unwanted activity often goes unrecognized and underestimated as a major problem in the food and beverage industries. In some cases, there is only a fine line between what is perceived as either a spoilage or beneficial activity. This review examines the occurrence and growth of yeasts in foods and beverages with respect to their spoilage activities, the biochemistry of this spoilage, and technologies for the enumeration and identification of spoilage yeasts. PMID:1733519

Fleet, G

1992-01-01

75

Antioxidant Activity of Agaricus brasiliensis Basidiocarps on Different Maturation Phases  

PubMed Central

Different maturation phases of basidiocarp could affect the bioactivity and concentration of some active substances. A. brasiliensis Wasser et al. (A. blazei Murrill) has shown antitumor activity that could be related to the antioxidant activity. However there is no information of the best basidiocarp maturation phase for extracting antioxidant substances in order to determine the moment of harvesting in mushroom cultivation. The objective of this work was to evaluate the antioxidant activity of A. brasiliensis strains on different basidiocarp maturation phases. The best condition for extraction of A. brasiliensis antioxidants is with methanol as solvent at 60 °C for 60 min. Strains with closed basidiocarp have higher antioxidant activity than with opened basidiocarp. Antioxidant activity varies in each strain. It was concluded that A. brasiliensis is a natural source of antioxidant compounds. Also there is higher antioxidant activity in closed than opened caps and consequently higher functional activity. It reinforces the synergic action among different A. brasiliensis compounds as a functional food and the importance of further investigation for isolation and characterization of antioxidant substances of A. brasiliensis. It also determines the best harvest period in order to obtain the highest antioxidant activity from basidiocarp. PMID:24031621

Mourão, Francielly; Harue Umeo, Suzana; Seiko Takemura, Orlando; Andrea Linde, Giani; Barros Colauto, Nelson

2011-01-01

76

Red yeast  

MedlinePLUS

... problems. Other conditions. More evidence is needed to rate the effectiveness of red yeast for these uses. ... can affect the muscles. Red yeast can also affect the muscles. Taking niacin along with ... cautious with this combination.Talk with your health provider.

77

Dry yeast  

NSDL National Science Digital Library

Yeast is a type of eukaryotic organism that can live in a dormant state. It can be activated from its dormant state by water and sugar. The yeast uses the sugar to grow and produces carbon dioxide gas as a byproduct.

Ranveig Thattai (None; )

2005-09-27

78

MODELING DROUGHT IMPACT ON H. BRASILIENSIS TRANSPIRATION, GROWTH AND LATEX PRODUCTION OF A  

E-print Network

1 MODELING DROUGHT IMPACT ON H. BRASILIENSIS 2 TRANSPIRATION, GROWTH AND LATEX PRODUCTION OF A HEVEA BRASILIENSIS STAND FACING DROUGHT IN4 NORTHEAST THAILAND: THE USE OF THE WANULCAS MODEL for natural rubber, Hevea brasiliensis is16 increasingly planted in drought prone areas

Boyer, Edmond

79

Antineoplasic activity of Agaricus brasiliensis basidiocarps on different maturation phases  

PubMed Central

The fungus Agaricus brasiliensis is a Basidiomycete studied because of its immunomodulation and/or antitumor substances. The objective of this study was to verify the Agaricus brasiliensis antineoplasic activity in vivo on different basidiocarp maturation phases on Sarcoma 180 cells implanted in mice. Sarcoma cells were implanted in mice and after seven days mice were divided in three groups. The first group was treated with saline solution, the second group was treated with closed basidiocarp extract solution and the third group was treated with opened basidiocarp extract solution. After 30 days of being daily orally treated with these three solutions all animals suffered euthanasia, and the splenic index, tumor mass and volume were determined. No significant differences of the tumor growth inhibition in function of the different basidiocarp maturation phases for the Agaricus brasiliensis strain were observed. The in vivo basidiocarp antineoplasic average activity was 89.22%. PMID:24031439

Mourão, Francielly; Linde, Giani Andrea; Messa, Valdeci; da Cunha Júnior, Paulo Luiz; da Silva, Aristeu Vieira; da Eira, Augusto Ferreira; Colauto, Nelson Barros

2009-01-01

80

ANIMAL MODEL OF NIPPOSTRONGYLUS BRASILIENSIS AND HELIGMOSOMOIDES POLYGYRUS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Animal models of Nippostrongylus brasiliensis and Heligmosomoides polygyrus infection are powerful tools for the investigation of the basic biology of immune responses and protective immunity. In particular they model the induction and maintenance of Th2 type immune responses and exhibiting all the ...

81

Temporal Dynamics of Reproduction in Hemiramphus brasiliensis (Osteichthyes: Hemiramphidae)  

PubMed Central

The reproductive aspects of Hemiramphus brasiliensis were analyzed with a view to verify the temporal dynamics of reproduction. This paper presents data on sex ratio, length at first sexual maturity, macroscopic and histological aspects of gonad development, gonadosomatic index (GSI), reproductive period, and fecundity of H. brasiliensis. The fishes were captured from the coastal waters of Rio Grande do Norte, northeastern Brazil. Females of this species predominated in the sampled population and were larger in size than the males. The length at the first sexual maturation of males was 20.8?cm and that of females was 21.5?cm. The macroscopic characteristics of the gonads indicated four maturation stages. Histological studies of gonads of H. brasiliensis showed six phases of oocyte development and four phases of spermatocyte development. The batch fecundity of this species was 1153 (±258.22) mature oocytes for 50?g body weight of female. The microscopic characteristics of gonad development indicate that H. brasiliensis is a multiple spawner, presenting a prolonged reproductive period during the whole year, with a peak in the month of April, and is considered as an opportunistic strategist. PMID:25512946

de Oliveira, Mônica Rocha

2014-01-01

82

Isolation and Molecular Characterization of 1-Aminocyclopropane-1-carboxylic Acid Synthase Genes in Hevea brasiliensis.  

PubMed

Ethylene is an important factor that stimulates Hevea brasiliensis to produce natural rubber. 1-Aminocyclopropane-1-carboxylic acid synthase (ACS) is a rate-limiting enzyme in ethylene biosynthesis. However, knowledge of the ACS gene family of H. brasiliensis is limited. In this study, nine ACS-like genes were identified in H. brasiliensis. Sequence and phylogenetic analysis results confirmed that seven isozymes (HbACS1-7) of these nine ACS-like genes were similar to ACS isozymes with ACS activity in other plants. Expression analysis results showed that seven ACS genes were differentially expressed in roots, barks, flowers, and leaves of H. brasiliensis. However, no or low ACS gene expression was detected in the latex of H. brasiliensis. Moreover, seven genes were differentially up-regulated by ethylene treatment. These results provided relevant information to help determine the functions of the ACS gene in H. brasiliensis, particularly the functions in regulating ethylene stimulation of latex production. PMID:25690030

Zhu, Jia-Hong; Xu, Jing; Chang, Wen-Jun; Zhang, Zhi-Li

2015-01-01

83

Isolation and Molecular Characterization of 1-Aminocyclopropane-1-carboxylic Acid Synthase Genes in Hevea brasiliensis  

PubMed Central

Ethylene is an important factor that stimulates Hevea brasiliensis to produce natural rubber. 1-Aminocyclopropane-1-carboxylic acid synthase (ACS) is a rate-limiting enzyme in ethylene biosynthesis. However, knowledge of the ACS gene family of H. brasiliensis is limited. In this study, nine ACS-like genes were identified in H. brasiliensis. Sequence and phylogenetic analysis results confirmed that seven isozymes (HbACS1–7) of these nine ACS-like genes were similar to ACS isozymes with ACS activity in other plants. Expression analysis results showed that seven ACS genes were differentially expressed in roots, barks, flowers, and leaves of H. brasiliensis. However, no or low ACS gene expression was detected in the latex of H. brasiliensis. Moreover, seven genes were differentially up-regulated by ethylene treatment.These results provided relevant information to help determine the functions of the ACS gene in H. brasiliensis, particularly the functions in regulating ethylene stimulation of latex production. PMID:25690030

Zhu, Jia-Hong; Xu, Jing; Chang, Wen-Jun; Zhang, Zhi-Li

2015-01-01

84

Homologous Hevea brasiliensis REF (Hevb1) and SRPP (Hevb3) present different auto-assembling.  

PubMed

HbREF and HbSRPP are two Hevea brasiliensis proteins present on rubber particles, and probably involved in the coagulation of latex. Their function is unclear, but we previously discovered that REF had amyloid properties, which could be of particular interest during the coagulation process. First, we confirmed that REF and SRPP, homologous and principal proteins in hevea latex, are not glycoproteins. In this work, we investigated various aspects of protein interactions: aggregation, auto-assembling, yeast and erythrocyte agglutination, co-interactions by various biochemical (PAGE, spectroscopy, microscopy), biophysical (DLS, ellipsometry) and structural (TEM, ATR-FTIR, PM-IRRAS) approaches. We demonstrated that both proteins are auto-assembling into different aggregative states: REF polymerizes as an amyloid rich in ?-sheets and forms quickly large aggregates (>?m), whereas SRPP auto-assembles in solution into stable nanomultimers of a more globular nature. Both proteins are however able to interact together, and SRPP may inhibit the amyloidogenesis of REF. REF is also able to interact with the membranes of yeasts and erythrocytes, leading to their agglutination. In addition, we also showed that both REF and SRPP did not have antimicrobial activity, whereas their activity on membranes has been clearly evidenced. We may suspect that these aggregative properties, even though they are clearly different, may occur during coagulation, when the membrane is destabilized. The interaction of proteins with membranes could help in the colloidal stability of latex, whereas the protein-protein interactions would contribute to the coagulation process, by bringing rubber particles together or eventually disrupting the particle monomembranes. PMID:24239687

Berthelot, Karine; Lecomte, Sophie; Estevez, Yannick; Coulary-Salin, Bénédicte; Peruch, Frédéric

2014-02-01

85

Draft genome sequence of the rubber tree Hevea brasiliensis  

PubMed Central

Background Hevea brasiliensis, a member of the Euphorbiaceae family, is the major commercial source of natural rubber (NR). NR is a latex polymer with high elasticity, flexibility, and resilience that has played a critical role in the world economy since 1876. Results Here, we report the draft genome sequence of H. brasiliensis. The assembly spans ~1.1 Gb of the estimated 2.15 Gb haploid genome. Overall, ~78% of the genome was identified as repetitive DNA. Gene prediction shows 68,955 gene models, of which 12.7% are unique to Hevea. Most of the key genes associated with rubber biosynthesis, rubberwood formation, disease resistance, and allergenicity have been identified. Conclusions The knowledge gained from this genome sequence will aid in the future development of high-yielding clones to keep up with the ever increasing need for natural rubber. PMID:23375136

2013-01-01

86

Polymorphic microsatellite loci from the endangered Giant Otter ( Pteronura brasiliensis)  

Microsoft Academic Search

We describe the first microsatellite loci isolated from the giant otter (Pteronura brasiliensis), an endangered mustelid endemic to South America. Fourteen di- and trinucleotide polymorphic loci were characterised in\\u000a fourteen individuals from the Pantanal wetlands, Central Brazil. Number of alleles per locus ranged from 2 to 5, and average\\u000a observed heterozygosity was 0.577. Two loci were in linkage disequilibrium, and

Carolina Ribas; Anderson V. Vasconcellos; Guilherme Mourão; William Magnusson; Antonio M. Solé-Cava; Haydée A. Cunha

87

Previous infection with the nematode Nippostrongylus brasiliensis alters the immune specific response against Chlamydophila abortus infection  

Microsoft Academic Search

An experimental mouse model to analyse the interaction between the immune responses elicited following infection with Nippostrongylus brasiliensis and Chlamydophila abortus has been established. Mice infected withC. abortus 7 days after N. brasiliensis showed an increased bacterial multiplication in spleen and liver compared to bacteria-alone infected mice. However the morbidity of these mice, expressed as weight loss, was significantly lower.

Antonio Buend??a; Padraic G. Fallon; Laura Del Rio; Nieves Ortega; Mar??a R. Caro; Mar??a C. Gallego; Jesús Salinas

2002-01-01

88

Genetic homogeneity and historical expansions of the slipper lobster, Scyllarides brasiliensis, in the south-west  

E-print Network

Genetic homogeneity and historical expansions of the slipper lobster, Scyllarides brasiliensis and population dynamics. The Brazilian slipper lobster, Scyllarides brasiliensis, is one of the most commercially important slipper lobster species in South America. We investigated, for the first time, the population

Solé-Cava, Antonio M.

89

Chromatographic Fractionation of Aggregation and Sex Pheromones of Nippostrongy/us brasiliensis (Nematoda)  

E-print Network

Chromatographic Fractionation of Aggregation and Sex Pheromones of Nippostrongy/us brasiliensis Nippostrongylus brasiliensis revealed two fractions with pheromonal activity. One active fraction with a suggested sexes by in vitro bioassay. A second re- gion of pheromone activity was found in only female

Hammock, Bruce D.

90

Pentose fermentation by yeasts  

Microsoft Academic Search

66 different yeast strains were screened for glucose, xylose and xylulose fermentation in shake flask cultures. None of the tested yeasts was able to grow or produce significant amounts of ethanol on xylose anaerobically. The best ethanol yields from xylulose were obtained with a wine yeast, two distillery yeasts, and a strain of Saccharomyces uvarum. The best conversion of xylulose

M.-L. Suihko; M. Dra?i?

1983-01-01

91

Yeast-Air Balloons  

NSDL National Science Digital Library

In this activity, learners make a yeast-air balloon to get a better idea of what yeast can do. Learners discover that the purpose of leaveners like yeast is to produce the gas that makes bread rise. Learners discover that as yeast feeds on sugar, it produces carbon dioxide which slowly fills the balloon.

The Exploratorium

2012-03-10

92

A Feast for Yeast  

NSDL National Science Digital Library

In this activity on page 6 of the PDF, learners investigate yeast. Learners prepare an experiment to observe what yeast cells like to eat. Learners feed the yeast cells various ingredients in plain bread--water, flour, sugar, and salt--to discover yeast's favorite food.

2013-07-08

93

Comparative Genomic Analysis of Human Fungal Pathogens Causing Paracoccidioidomycosis  

PubMed Central

Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasiliensis (Pb03 and Pb18) and one strain of Paracoccidioides lutzii (Pb01). These genomes range in size from 29.1 Mb to 32.9 Mb and encode 7,610 to 8,130 genes. To enable genetic studies, we mapped 94% of the P. brasiliensis Pb18 assembly onto five chromosomes. We characterized gene family content across Onygenales and related fungi, and within Paracoccidioides we found expansions of the fungal-specific kinase family FunK1. Additionally, the Onygenales have lost many genes involved in carbohydrate metabolism and fewer genes involved in protein metabolism, resulting in a higher ratio of proteases to carbohydrate active enzymes in the Onygenales than their relatives. To determine if gene content correlated with growth on different substrates, we screened the non-pathogenic onygenale Uncinocarpus reesii, which has orthologs for 91% of Paracoccidioides metabolic genes, for growth on 190 carbon sources. U. reesii showed growth on a limited range of carbohydrates, primarily basic plant sugars and cell wall components; this suggests that Onygenales, including dimorphic fungi, can degrade cellulosic plant material in the soil. In addition, U. reesii grew on gelatin and a wide range of dipeptides and amino acids, indicating a preference for proteinaceous growth substrates over carbohydrates, which may enable these fungi to also degrade animal biomass. These capabilities for degrading plant and animal substrates suggest a duality in lifestyle that could enable pathogenic species of Onygenales to transfer from soil to animal hosts. PMID:22046142

Desjardins, Christopher A.; Champion, Mia D.; Holder, Jason W.; Muszewska, Anna; Goldberg, Jonathan; Bailão, Alexandre M.; Brigido, Marcelo Macedo; Ferreira, Márcia Eliana da Silva; Garcia, Ana Maria; Grynberg, Marcin; Gujja, Sharvari; Heiman, David I.; Henn, Matthew R.; Kodira, Chinnappa D.; León-Narváez, Henry; Longo, Larissa V. G.; Ma, Li-Jun; Malavazi, Iran; Matsuo, Alisson L.; Morais, Flavia V.; Pereira, Maristela; Rodríguez-Brito, Sabrina; Sakthikumar, Sharadha; Salem-Izacc, Silvia M.; Sykes, Sean M.; Teixeira, Marcus Melo; Vallejo, Milene C.; Walter, Maria Emília Machado Telles; Yandava, Chandri; Young, Sarah; Zeng, Qiandong; Zucker, Jeremy; Felipe, Maria Sueli; Goldman, Gustavo H.; Haas, Brian J.; McEwen, Juan G.; Nino-Vega, Gustavo; Puccia, Rosana; San-Blas, Gioconda; Soares, Celia Maria de Almeida; Birren, Bruce W.; Cuomo, Christina A.

2011-01-01

94

Non-conventional yeasts.  

PubMed

In the beginning there was yeast, and it raised bread, brewed beer, and made wine. After many not days but centuries and even millenia later, it was named Saccharomyces cerevisiae. After more years and centuries there was another yeast, and it was named Schizosaccharomyces pombe; now there were two stars in the yeast heaven. In only a few more years there were other yeasts, and then more, and more, and more. The era of the non-conventional yeasts had begun. PMID:11878307

Spencer, J F T; Ragout de Spencer, A L; Laluce, C

2002-02-01

95

Revalidation and redescription of Triatoma brasiliensis macromelasoma Galvão, 1956 and an identification key for the Triatoma brasiliensis complex (Hemiptera: Reduviidae: Triatominae)  

PubMed Central

Triatoma brasiliensis macromelasoma is revalidated based on the results of previous multidisciplinary studies on the Triatoma brasiliensis complex, consisting of crossing experiments and morphological, biological, ecological and molecular analyses. These taxonomic tools showed the closest relationship between T. b. macromelasoma and Triatoma brasiliensis brasiliensis. T. b. macromelasoma is redescribed based on specimens collected in the type locality and specimens from a F1 colony. The complex now comprises T. b. brasiliensis, T. b. macromelasoma, Triatoma melanica, Triatoma juazeirensis and Triatoma sherlocki. An identification key for all members of the complex is presented. This detailed comparative study of the morphological features of T. b. macromelasoma and the remaining members of the complex corroborates results from multidisciplinary analyses, suggesting that the subspecific status is applicable. This subspecies can be distinguished by the following combination of features: a pronotum with 1+1 narrow brownish-yellow stripes on the submedian carinae, not attaining its apex, hemelytra with membrane cells darkened on the central portion and legs with an incomplete brownish-yellow ring on the apical half of the femora. Because the T. brasiliensis complex is of distinct epidemiological importance throughout its geographic distribution, a precise identification of its five members is important for monitoring and controlling actions against Chagas disease transmission. PMID:24037202

Costa, Jane; Correia, Nathália Cordeiro; Neiva, Vanessa Lima; Gonçalves, Teresa Cristina Monte; Felix, Márcio

2013-01-01

96

Immunomodulatory effect of diethylcarbamazine in mice infected with Nocardia brasiliensis.  

PubMed

We tested whether diethylcarbamazine (DEC) or ivermectin (IVM), both antiparasitic drugs with reported immunomodulatory properties, were able to affect the immune system to potentiate host defense mechanisms and protect against actinomycetoma in a mouse model. Male BALB/c mice of 10-12 weeks of age were injected with either Nocardia brasiliensis or saline solution. Recorded were the effects of a treatment by DEC (6 mg/kg per os daily for one week) or IVM (200 ?g/kg subcutaneously on days 1 and 3) on (i) the development of mycetoma lesion, (ii) the expression of reactive oxygen intermediates (ROI) by phagocytes, (iii) the proliferation index of lymphocytes and (iv) antibody production of IgG and IgM. After an initial lesion in all mice, DEC inhibited a full development and progression of actinomycetoma resulting in a reduced lesion size (p < 0.001). IVM had no inhibitory effect on the development of mycetoma. Furthermore, DEC treatment was associated with a significant enhancement of ROI expression (p < 0.05) by polymorphonuclear neutrophils at day 3 after infection. Lymphocyte proliferation in response to N. brasiliensis antigens and concanavalin A in DEC-treated group was higher than in non-treated group at day 21 and 28 postinfection (p < 0.01). Significant changes in antibody response were not observed. By all parameters tested, DEC was superior to IVM regarding immunostimulatory potency. In conclusion, DEC expressed an in vivo influence on the immune status during the infection by N. brasiliensis leading to retrogression of the mycetoma and increasing cellular immune responses. Our findings may indicate a potential use of DEC as a putative adjuvant in infectious disease or vaccination. PMID:25150175

García-Hernández, M; Castro-Corona, M A; Segoviano-Ramírez, J C; Brattig, N W; Medina-De la Garza, C E

2014-11-01

97

Taxonomic and Functional Microbial Signatures of the Endemic Marine Sponge Arenosclera brasiliensis  

PubMed Central

The endemic marine sponge Arenosclera brasiliensis (Porifera, Demospongiae, Haplosclerida) is a known source of secondary metabolites such as arenosclerins A-C. In the present study, we established the composition of the A. brasiliensis microbiome and the metabolic pathways associated with this community. We used 454 shotgun pyrosequencing to generate approximately 640,000 high-quality sponge-derived sequences (?150 Mb). Clustering analysis including sponge, seawater and twenty-three other metagenomes derived from marine animal microbiomes shows that A. brasiliensis contains a specific microbiome. Fourteen bacterial phyla (including Proteobacteria, Cyanobacteria, Actinobacteria, Bacteroidetes, Firmicutes and Cloroflexi) were consistently found in the A. brasiliensis metagenomes. The A. brasiliensis microbiome is enriched for Betaproteobacteria (e.g., Burkholderia) and Gammaproteobacteria (e.g., Pseudomonas and Alteromonas) compared with the surrounding planktonic microbial communities. Functional analysis based on Rapid Annotation using Subsystem Technology (RAST) indicated that the A. brasiliensis microbiome is enriched for sequences associated with membrane transport and one-carbon metabolism. In addition, there was an overrepresentation of sequences associated with aerobic and anaerobic metabolism as well as the synthesis and degradation of secondary metabolites. This study represents the first analysis of sponge-associated microbial communities via shotgun pyrosequencing, a strategy commonly applied in similar analyses in other marine invertebrate hosts, such as corals and algae. We demonstrate that A. brasiliensis has a unique microbiome that is distinct from that of the surrounding planktonic microbes and from other marine organisms, indicating a species-specific microbiome. PMID:22768320

Trindade-Silva, Amaro E.; Rua, Cintia; Silva, Genivaldo G. Z.; Dutilh, Bas E.; Moreira, Ana Paula B.; Edwards, Robert A.; Hajdu, Eduardo; Lobo-Hajdu, Gisele; Vasconcelos, Ana Tereza; Berlinck, Roberto G. S.; Thompson, Fabiano L.

2012-01-01

98

Yeast Education Network  

NSDL National Science Digital Library

The Yeast Education Network provides a variety of resources to facilitate use of the budding yeast Saccharomyces cerevisiae in undergraduate science curricula. Laboratory, classroom, and computer-based activities can be used with college and advanced high school students.

99

Vaginal Yeast Infections  

MedlinePLUS

... infection from your sexual partner. Condoms and dental dams may help prevent getting or passing yeast infections ... infection from your sexual partner. Condoms and dental dams may help prevent getting or passing yeast infections ...

100

Yeast Based Sensors  

NASA Astrophysics Data System (ADS)

Since the first microbial cell sensor was studied by Karube et al. in 1977, many types of yeast based sensors have been developed as analytical tools. Yeasts are known as facultative anaerobes. Facultative anaerobes can survive in both aerobic and anaerobic conditions. The yeast based sensor consisted of a DO electrode and an immobilized omnivorous yeast. In yeast based sensor development, many kinds of yeast have been employed by applying their characteristics to adapt to the analyte. For example, Trichosporon cutaneum was used to estimate organic pollution in industrial wastewater. Yeast based sensors are suitable for online control of biochemical processes and for environmental monitoring. In this review, principles and applications of yeast based sensors are summarized.

Shimomura-Shimizu, Mifumi; Karube, Isao

101

Black yeast-like fungi associated with Lethargic Crab Disease (LCD) in the mangrove-land crab, Ucides cordatus (Ocypodidae).  

PubMed

Lethargic Crab Disease (LCD) caused extensive epizootic mortality of the mangrove land crab Ucides cordatus (Brachyura: Ocypodidae) along the Brazilian coast, mainly in the Northeastern region. The disease was named after the symptoms of slow movement of infected crabs. Causative agents were suspected to be two black yeast-like fungi of the family Herpotrichiellaceae (ascomycete order Chaetothyriales), judged by infected tissue biopsies from moribund U. cordatus. The aim of the present study is to prove that two species are involved in the disease: the recently described black yeast Exophiala cancerae, but also a less virulent, hitherto undescribed fonsecaea-like species, introduced here as the novel species Fonsecaea brasiliensis. Strains were identified by ITS rDNA sequencing, and species borderlines were established by multilocus sequencing and AFLP analysis. Fonsecaea brasiliensis proved to be closely related to the pathogenic species Cladophialophora devriesii which originally was isolated from a systemic infection in a human patient. The virulence of F. brasiliensis is lower than that of E. cancerae, as established by artificial inoculation of mangrove crabs. PMID:22440399

Vicente, Vania A; Orélis-Ribeiro, R; Najafzadeh, M J; Sun, Jiufeng; Guerra, Raquel Schier; Miesch, Stephanie; Ostrensky, Antonio; Meis, Jacques F; Klaassen, Corné H; de Hoog, G S; Boeger, Walter A

2012-07-01

102

Xylose fermentation by yeasts  

Microsoft Academic Search

Utilization and fermentation of xylose by the yeasts Pachysolen tannophilus I fGB 0101 and Pichia stipitis 5773 to 5776 under aerobic and anaerobic conditions are investigated. Pa. tannophilus requires biotin and thiamine for growth, whereas Pi. stipitis does not, and growth of both yeasts is stimulated by yeast extract. Pi. stipitis converts xylose (30 g\\/l) to ethanol under anaerobic conditions

H. Dellweg; M. Rizzi; H. Methner; D. Debus

1984-01-01

103

National Plant Diagnostic Network, Taxonomic training videos: Aphids under the microscope - Cerataphis brasiliensis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides provides training to identify the palm aphid, Cerataphis brasiliensis, using a compound microscope and an electronic identification key called “LUCID.” The video demonstrates key morphological structures...

104

Isolation and characterization of microsatellite markers in the Serra Spanish mackerel, Scomberomorus brasiliensis  

Technology Transfer Automated Retrieval System (TEKTRAN)

Thirteen nuclear-encoded microsatellites from a genomic DNA library of Serra Spanish mackerel, Scomberomorus brasiliensis, were isolated and characterized. The microsatellites include 10 perfect repeats (8 tetranucleotide and 2 dinucleotide) and 3 imperfect repeats (2 tetranucleotide and 1 dinucleo...

105

RNA-Seq analysis and de novo transcriptome assembly of Hevea brasiliensis  

Microsoft Academic Search

Hevea brasiliensis, being the only source of commercial natural rubber, is an extremely economically important crop. In an effort to facilitate\\u000a biological, biochemical and molecular research in rubber biosynthesis, here we report the use of next-generation massively\\u000a parallel sequencing technologies and de novo transcriptome assembly to gain a comprehensive overview of the H. brasiliensis transcriptome. The sequencing output generated more

Zhihui Xia; Huimin Xu; Jinling Zhai; Dejun Li; Hongli Luo; Chaozu He; Xi Huang

106

Complete mitochondrial genome of Salminus brasiliensis (Characiformes, Characidae).  

PubMed

Abstract We report the complete mitochondrial genome of the fish Salminus brasiliensis, popularly known as dourado. It is a circular, 17,721?bp long DNA molecule, containing 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a non-coding Control Region of 2128?bp, a relatively large molecule when compared to other closely related fishes. All protein-coding genes are on the heavy strand, except for Nd6, and all have ATG as the start codon, except for Cox1 gene which has a GTG start codon. Seven protein-coding genes have incomplete stop codons (Nd2, Cox2, Atp6, Nd4, and Cytb have T-?-, and Cox3 and Nd3 have TA-). TAG is the stop codon for Nd6 and AGG is the stop codon for Cox1. PMID:25208163

Brandão-Dias, Pedro Ferreira Pinto; Carmo, Anderson Oliveira do; Martins, Ana Paula Vimieiro; Pimenta, Ricardo José Gonzaga; Alves, Carlos Bernardo Mascarenhas; Kalapothakis, Evanguedes

2014-09-10

107

Tick toxicosis in a dog bitten by Ornithodoros brasiliensis.  

PubMed

Ticks are hematophagous parasites of people and animals and are a public health hazard in several countries. They are vectors of infectious diseases; in addition, the bite of some ticks, mainly from the Ornithodoros genus, may lead to local lesions and systemic illness, referred to as tick toxicosis. In this report, we describe a dog bitten by Ornithodoros brasiliensis, popularly known as the mouro tick. The main clinical findings were disseminated skin rash, pruritus, mucosal hyperemia, lethargy, and fever. Laboratory abnormalities 48 hours after the bites occurred included mild nonregenerative anemia, eosinophilia, basophilia, increased serum creatine kinase activity, increased serum C-reactive protein concentration, and prolonged coagulation times. Tick-borne pathogens were not detected by PCR analysis or serologic testing, supporting the diagnosis of a noninfectious syndrome due to tick bite, compatible with tick toxicosis. PMID:21827517

Reck, José; Soares, João Fábio; Termignoni, Carlos; Labruna, Marcelo B; Martins, João Ricardo

2011-09-01

108

Drimanes from Drimys brasiliensis with leishmanicidal and antimalarial activity  

PubMed Central

This paper evaluates CHCl3 and CH3OH extracts of the stem bark, branches and leaves of Drimys brasiliensis and drimane sesquiterpenes isolated from the stem bark against strains of Leishmania amazonensis and Leishmania braziliensis promastigotes and Plasmodium falciparum trophozoites. All of the extracts and compounds were tested in cell lines in comparison with reference standards and cell viability was determined by the XTT method. The CHCl3 and CH3OH extracts from the stem bark and branches yielded promising results against two strains of Leishmania, with 50% inhibitory concentrations (IC50 ) values ranging from 39-100 µg/mL. The CHCl3 extract of the stem bark returned IC50 values of 39 and 40.6 µg/mL for L. amazonensis and L. braziliensis, respectively. The drimanes were relatively effective: 1-?-(p-coumaroyloxy)-polygodial produced IC50 values of 5.55 and 2.52 µM for L. amazonensis and L. braziliensis, respectively, compared with 1-?-(p-methoxycinnamoyl)-polygodial, which produced respective IC50 values of 15.85 and 17.80 µM. The CHCl3 extract demonstrated activity (IC50 of 3.0 µg/mL) against P. falciparum. The IC50 values of 1-?-(p-cumaroyloxyl)-polygodial and 1-?-(p-methoxycinnamoyl)-polygodial were 1.01 and 4.87 µM, respectively, for the trophozoite strain. Therefore, the results suggest that D. brasiliensis is a promising plant from which to obtain new and effective antiparasitic agents. PMID:23579790

Claudino, Vanessa Duarte; da Silva, Kesia Caroline; Cechinel, Valdir; Yunes, Rosendo Augusto; Monache, Franco Delle; Giménez, Alberto; Salamanca, Efrain; Gutierrez-Yapu, David; Malheiros, Angela

2013-01-01

109

Drimanes from Drimys brasiliensis with leishmanicidal and antimalarial activity.  

PubMed

This paper evaluates CHCl3 and CH3OH extracts of the stem bark, branches and leaves of Drimys brasiliensis and drimane sesquiterpenes isolated from the stem bark against strains of Leishmania amazonensis and Leishmania braziliensis promastigotes and Plasmodium falciparum trophozoites. All of the extracts and compounds were tested in cell lines in comparison with reference standards and cell viability was determined by the XTT method. The CHCl3 and CH3OH extracts from the stem bark and branches yielded promising results against two strains of Leishmania, with 50% inhibitory concentrations (IC50 ) values ranging from 39-100 µg/mL. The CHCl3 extract of the stem bark returned IC50 values of 39 and 40.6 µg/mL for L. amazonensis and L. braziliensis, respectively. The drimanes were relatively effective: 1-?-(p-coumaroyloxy)-polygodial produced IC50 values of 5.55 and 2.52 µM for L. amazonensis and L. braziliensis, respectively, compared with 1-?-(p-methoxycinnamoyl)-polygodial, which produced respective IC50 values of 15.85 and 17.80 µM. The CHCl3 extract demonstrated activity (IC50 of 3.0 µg/mL) against P. falciparum. The IC50 values of 1-?-(p-cumaroyloxyl)-polygodial and 1-?-(p-methoxycinnamoyl)-polygodial were 1.01 and 4.87 µM, respectively, for the trophozoite strain. Therefore, the results suggest that D. brasiliensis is a promising plant from which to obtain new and effective antiparasitic agents. PMID:23579790

Claudino, Vanessa Duarte; da Silva, Kesia Caroline; Cechinel Filho, Valdir; Yunes, Rosendo Augusto; Delle Monache, Franco; Giménez, Alberto; Salamanca, Efrain; Gutierrez-Yapu, David; Malheiros, Angela

2013-04-01

110

Monoclonal antibodies to P24 and P61 immunodominant antigens from Nocardia brasiliensis.  

PubMed Central

We prepared a Nocardia brasiliensis cell extract and purified two immunodominant antigens with molecular weights of 61,000 and 24,000. The isolated proteins were shown to be reasonably pure when analyzed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (8 to 18% polyacrylamide gradient) and stained with Coomassie blue and silver nitrate. By using an immunoelectrotransfer blot method (Western blotting), we demonstrated that these two purified proteins reacted strongly with serum from N. brasiliensis-infected mycetoma patients. To obtain anti-P61 and anti-P24 monoclonal antibodies (MAbs), we used an N. brasiliensis cell extract as the antigen for the first immunization; 2 weeks later female mice were reimmunized with a semipurified antigen containing the P24 or P61 fraction. A booster injection was given 3 days before the fusion was carried out. Two hybrids that reacted strongly with P24 were cloned by limiting dilution, the generated MAbs were analyzed for isotyping, and their specificity was tested in a Western blot assay with cell extracts from Nocardia asteroides and Mycobacterium tuberculosis cultures. Anti-P24 MAbs were shown to be specific for N. brasiliensis HUJEG-1 and did not cross-react with either the N. asteroides or M. tuberculosis strains used. However, additional studies with several N. asteroides and N. brasiliensis strains are needed to investigate whether there are cross-reactions between strains or species when these MAbs are used. The anti-P61 and anti-24 MAbs were used to locate the antigen in N. brasiliensis cells by immunofluorescence. The lack of reaction with intact cells suggests that the P24 and P61 antigens are not exposed in the complete bacterial cell surface or that the recognized epitopes are different. Only one anti-P61 MAb that reacted specifically with the N. brasiliensis cell extract was obtained. PMID:9067645

Salinas-Carmona, M C; Castro-Corona, M A; Sepúlveda-Saavedra, J; Perez, L I

1997-01-01

111

Population Growth in Yeasts  

NSDL National Science Digital Library

This lesson is the second of two that explore cellular respiration and population growth in yeasts. In the first lesson, students set up a simple way to indirectly observe and quantify the amount of respiration occurring in yeast-molasses cultures. Based on questions that arose during the first lesson and its associated activity, students in this lesson work in small groups to design experiments that determine how environmental factors affect yeast population growth.

Engineering K-PhD Program,

112

Red Yeast Rice: An Introduction  

MedlinePLUS

... links Read our disclaimer about external links Menu Red Yeast Rice: An Introduction On this page: Key ... will help ensure coordinated and safe care. About Red Yeast Rice Red yeast rice is made by ...

113

Sporotrichosis in Rio de Janeiro, Brazil: Sporothrix brasiliensis Is Associated with Atypical Clinical Presentations  

PubMed Central

Background There have been several recent changes in the taxonomy of Sporothrix schenckii as well as new observations regarding the clinical aspects of sporotrichosis. In this study, we determined the identification of the Sporothrix species associated with both classic and unusual clinical aspects of sporotrichosis observed in the endemic area of sporotrichosis in Rio de Janeiro, Brazil. Methodology/Principal Findings To verify whether S. brasiliensis is associated with clinical manifestations of sporotrichosis, a cross-sectional study was performed in which Sporothrix isolates from 50 patients with different clinical manifestations were analyzed and their isolates were studied by phenotypic and genotypic methods. Data from these patients revealed a distinct clinical picture and therapeutic response in infections caused by Sporothrix brasiliensis (n?=?45) compared to patients with S. schenckii sensu stricto (n?=?5). S. brasiliensis was associated with disseminated cutaneous infection without underlying disease, hypersensitivity reactions, and mucosal infection, whereas patients with S. schenckii presented with less severe and more often localized disease, similar to the majority of previously described sporotrichosis cases. Interestingly, S. brasiliensis-infected patients overall required shorter durations of itraconazole (median 16 weeks) compared to the individuals with S. schenckii (median 24 weeks). Conclusions/Significance These findings suggest that Sporothrix species are linked to different clinical manifestations of sporotrichosis and that S. brasiliensis is effectively treated with oral itraconazole. PMID:25233227

Almeida-Paes, Rodrigo; de Oliveira, Manoel Marques Evangelista; Freitas, Dayvison Francis Saraiva; do Valle, Antônio Carlos Francesconi; Zancopé-Oliveira, Rosely Maria; Gutierrez-Galhardo, Maria Clara

2014-01-01

114

Metabolic routes affecting rubber biosynthesis in Hevea brasiliensis latex  

PubMed Central

The cytosolic mevalonate (MVA) pathway in Hevea brasiliensis latex is the conventionally accepted pathway which provides isopentenyl diphosphate (IPP) for cis-polyisoprene (rubber) biosynthesis. However, the plastidic 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway may be an alternative source of IPP since its more recent discovery in plants. Quantitative RT-PCR (qRT-PCR) expression profiles of genes from both pathways in latex showed that subcellular compartmentalization of IPP for cis-polyisoprene synthesis is related to the degree of plastidic carotenoid synthesis. From this, the occurrence of two schemes of IPP partitioning and utilization within one species is proposed whereby the supply of IPP for cis-polyisoprene from the MEP pathway is related to carotenoid production in latex. Subsequently, a set of latex unique gene transcripts was sequenced and assembled and they were then mapped to IPP-requiring pathways. Up to eight such pathways, including cis-polyisoprene biosynthesis, were identified. Our findings on pre- and post-IPP metabolic routes form an important aspect of a pathway knowledge-driven approach to enhancing cis-polyisoprene biosynthesis in transgenic rubber trees. PMID:22162870

Chow, Keng-See; Mat-Isa, Mohd.-Noor; Bahari, Azlina; Ghazali, Ahmad-Kamal; Alias, Halimah; Mohd.-Zainuddin, Zainorlina; Hoh, Chee-Choong; Wan, Kiew-Lian

2012-01-01

115

Biological control of Rigidoporus lignosus in Hevea brasiliensis in Nigeria.  

PubMed

The study was conducted to evaluate in vitro and in vivo control of fungal antagonists on Rigidoporus lignosus (klotzsch) Imaz in Hevea brasiliensis (Willd. ex A. Juss.) Muell. Arg. in the rain forest zone of Nigeria. In vitro assessments of biological agents were carried out in dixenic cultures in Petri plates. In vivo tests were carried out in the nursery using Hypocrea virens and Hypocrea jecorina. Significant differences were observed with the dual inoculations of fungal antagonists and R. lignosus inoculated the same day, and the antagonists inoculated 24 h before inoculation of R. lignosus. Hypocrea jecorina was most effective in the control of R. lignosus with percentage inhibition of 86.83 %. Hypocrea virens, H. jecorina, Trichoderma spirale, Trichoderma sp., Trichoderma sp. Pers, and Hypocrea lixii were effective on R. lignosus. Fungal antagonists inoculated 24 h before inoculation of R. lignosus exhibited higher inhibitory efficacies than antagonists and R. lignosus inoculated the same day. In the in vivo evaluation of fungi antagonists on R. lignosus, seedlings in H. jecorina treatment at 60 d and H. virens treatment at 150 d after inoculations respectively had the highest plant heaths (highest length of stem and length of tap rot, lowest plant death, and least foliar symptom) compared to the control. Mortality rate was higher at 60 d after inoculation and decline from the third months onward. Significant differences were observed between the control and R. lignosus treatment in all the parameters evaluated. PMID:25601145

Ogbebor, Nicholas Obehi; Adekunle, Adefunke Temitayo; Eghafona, Odeh Nosakhare; Ogboghodo, Abraham Ikponmwosa

2015-01-01

116

Temporal auditory summation in the echolocating bat, Tadarida brasiliensis.  

PubMed

Auditory thresholds improve with increasing signal duration within the maximum integration time of the auditory system, a phenomenon called temporal summation. The temporal summation function is a basic characteristic of particular relevance for bat sonar, as it determines the ability to detect targets with short echolocation calls. Temporal summation was studied in 6 Mexican free-tailed bats (Tadarida brasiliensis) in a forced two-choice behavioural test. Masked auditory thresholds for 40-kHz test tone pulses with durations between 2 ms and 400 ms were determined in broadband noise of two different spectrum levels (-18 dB, +17 dB). At both masker levels, thresholds decreased by considerably more than 10 dB per decade of duration. The time constants of the summation functions, which are a measure of the maximum integration time, shortened significantly with increasing masker level from 62 ms to 14 ms. The steep summation functions are only partly accounted for by spectral splatter. This suggests that the bats are capable of a neural overintegration of sound intensity. Finally, it is shown that such short time constants are typical for echolocating animals, and the implications of the found summation functions for echolocation are considered. PMID:7928724

Schmidt, S; Thaller, J

1994-06-15

117

Xylose fermentation by yeasts  

Microsoft Academic Search

Summary Furfural as a product from thermic wood hydrolysis processes may be inhibitory to growth and fermentation of yeast cells. In order to determine the influence on the aerobic growth of the yeastPichiastipitis, expermiments were conducted in stirred reactors with the addition of furfural.

B. Weigert; C. Klein; M. Rizzi; C. Lauterbach; H. Dellweg

1988-01-01

118

Yeasts: Neglected Pathogens  

Microsoft Academic Search

Background: Current research on Crohn’s disease (CD) concerns molecular events related to loss of tolerance to microbes that could trigger or maintain inflammation in genetically susceptible individuals. CD is also associated with antimicrobial antibodies, including the antibodies we described against yeast oligomannosides (ASCA). This prompted us to investigate a role for another yeast, Candida albicans, a very common commensal of

Daniel Poulain; Boualem Sendid; Annie Standaert-Vitse; Chantal Fradin; Thierry Jouault; Samir Jawhara; Jean-Frederic Colombel

2009-01-01

119

Alcoholic Fermentation in Yeast  

NSDL National Science Digital Library

Students learn about the basics of aerobic cellular respiration and alcoholic fermentation and design and carry out experiments to test how variables such as sugar concentration influence the rate of alcoholic fermentation in yeast. In an optional extension activity students can use their yeast mixture to make a small roll of bread.

Ingrid Waldron

120

Therapeutic Effect of Agaricus brasiliensis on Phenylhydrazine-Induced Neonatal Jaundice in Rats  

PubMed Central

The present study was designed to investigate the effect of Agaricus brasiliensis extract (ABE) on phenylhydrazine-induced neonatal jaundice in rats. Administration of ABE dose-dependently reduced the elevated bilirubin level induced by phenylhydrazine. It can be somewhat supported from the results of in vitro bilirubin degradation experiment. ABE treatment also reduced the total antioxidant status (TAOS), cascade O2?/SOD, level of NF-?B protein, and adrenomedullin (AM). Overall, the results of this study demonstrated that Agaricus brasiliensis extract may be beneficial to reducing bilirubin level without causing hepatotoxicity in neonatal jaundice.

Zhang, Lan; Yuan, Bo; Wang, HuiPing; Gao, Ya

2015-01-01

121

Immunomodulating Activity of Agaricus brasiliensis KA21 in Mice and in Human Volunteers  

PubMed Central

We performed studies on murine models and human volunteers to examine the immunoenhancing effects of the naturally outdoor-cultivated fruit body of Agaricus brasiliensis KA21 (i.e. Agaricus blazei). Antitumor, leukocyte-enhancing, hepatopathy-alleviating and endotoxin shock-alleviating effects were found in mice. In the human study, percentage body fat, percentage visceral fat, blood cholesterol level and blood glucose level were decreased, and natural killer cell activity was increased. Taken together, the results strongly suggest that the A. brasiliensis fruit body is useful as a health-promoting food. PMID:18604247

Fukuwatari, Yasushi; Okumura, Ko; Takeda, Kazuyoshi; Ishibashi, Ken-ichi; Furukawa, Mai; Ohno, Naohito; Mori, Kazu; Gao, Ming; Motoi, Masuro

2008-01-01

122

Assessment of plant lectin antifungal potential against yeasts of major importance in medical mycology.  

PubMed

The search for new compounds with antifungal activity is accelerating due to rising yeast and fungal resistance to commonly prescribed drugs. Among the molecules being investigated, plant lectins can be highlighted. The present work shows the potential of six plant lectins which were tested in vitro against yeasts of medical importance, Candida albicans, Candida tropicalis, Candida parapsilosis, Cryptococcus gattii, Cryptococcus neoformans, Malassezia pachydermatis, Rhodotorula sp. and Trichosporon sp. Broth microdilution susceptibility testing was performed in accordance with standard protocols to evaluate antifungal activity. Minimum inhibitory concentration (MIC) was determined at 80% yeast growth inhibition, whereas the minimum fungicidal concentration (MFC) was evaluated after making the subcultures of each dilution. Only C. parapsilosis growth was inhibited by the lectins tested. Abelmoschus esculentus lectin showed the highest MIC (0.97 ?g ml(-1)). Lectins from Canavalia brasiliensis, Mucuna pruriens and Clitoria fairchildiana presented the highest MFC at (3.90 ?g ml(-1)). These results encourage further studies with wider yeast strain selections, and open new perspectives for the development of pharmacological molecules. PMID:23161017

Klafke, Gabriel Baracy; Moreira, Gustavo Marçal Schmitt Garcia; Monte, Leonardo Garcia; Pereira, Juliano Lacava; Brandolt, Tchana Martinez; Xavier, Melissa Orzechowski; Santi-Gadelha, Tatiane; Dellagostin, Odir Antonio; Pinto, Luciano da Silva

2013-02-01

123

Yeast expression platforms  

Microsoft Academic Search

Yeasts provide attractive expression platforms. They combine ease of genetic manipulations and the option for a simple fermentation\\u000a design of a microbial organism with the capabilities of an eukaryotic organism to secrete and to modify a protein according\\u000a to a general eukaryotic scheme. For platform applications, a range of yeast species has been developed during the last decades.\\u000a We present

Erik Böer; Gerhard Steinborn; Gotthard Kunze; Gerd Gellissen

2007-01-01

124

Nitrile Metabolizing Yeasts  

NASA Astrophysics Data System (ADS)

Nitriles and amides are widely distributed in the biotic and abiotic components of our ecosystem. Nitrile form an important group of organic compounds which find their applications in the synthesis of a large number of compounds used as/in pharmaceutical, cosmetics, plastics, dyes, etc>. Nitriles are mainly hydro-lyzed to corresponding amide/acid in organic chemistry. Industrial and agricultural activities have also lead to release of nitriles and amides into the environment and some of them pose threat to human health. Biocatalysis and biotransformations are increasingly replacing chemical routes of synthesis in organic chemistry as a part of ‘green chemistry’. Nitrile metabolizing organisms or enzymes thus has assumed greater significance in all these years to convert nitriles to amides/ acids. The nitrile metabolizing enzymes are widely present in bacteria, fungi and yeasts. Yeasts metabolize nitriles through nitrilase and/or nitrile hydratase and amidase enzymes. Only few yeasts have been reported to possess aldoxime dehydratase. More than sixty nitrile metabolizing yeast strains have been hither to isolated from cyanide treatment bioreactor, fermented foods and soil. Most of the yeasts contain nitrile hydratase-amidase system for metabolizing nitriles. Transformations of nitriles to amides/acids have been carried out with free and immobilized yeast cells. The nitrilases of Torulopsis candida>and Exophiala oligosperma>R1 are enantioselec-tive and regiospecific respectively. Geotrichum>sp. JR1 grows in the presence of 2M acetonitrile and may have potential for application in bioremediation of nitrile contaminated soil/water. The nitrilase of E. oligosperma>R1 being active at low pH (3-6) has shown promise for the hydroxy acids. Immobilized yeast cells hydrolyze some additional nitriles in comparison to free cells. It is expected that more focus in future will be on purification, characterization, cloning, expression and immobilization of nitrile metabolizing enzymes of yeasts.

Bhalla, Tek Chand; Sharma, Monica; Sharma, Nitya Nand

125

Forces in yeast flocculation.  

PubMed

In the baker's yeast Saccharomyces cerevisiae, cell-cell adhesion ("flocculation") is conferred by a family of lectin-like proteins known as the flocculin (Flo) proteins. Knowledge of the adhesive and mechanical properties of flocculins is important for understanding the mechanisms of yeast adhesion, and may help controlling yeast behaviour in biotechnology. We use single-molecule and single-cell atomic force microscopy (AFM) to explore the nanoscale forces engaged in yeast flocculation, focusing on the role of Flo1 as a prototype of flocculins. Using AFM tips labelled with mannose, we detect single flocculins on Flo1-expressing cells, showing they are widely exposed on the cell surface. When subjected to force, individual Flo1 proteins display two distinct force responses, i.e. weak lectin binding forces and strong unfolding forces reflecting the force-induced extension of hydrophobic tandem repeats. We demonstrate that cell-cell adhesion bonds also involve multiple weak lectin interactions together with strong unfolding forces, both associated with Flo1 molecules. Single-molecule and single-cell data correlate with microscale cell adhesion behaviour, suggesting strongly that Flo1 mechanics is critical for yeast flocculation. These results favour a model in which not only weak lectin-sugar interactions are involved in yeast flocculation but also strong hydrophobic interactions resulting from protein unfolding. PMID:25515338

El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Vincent, Stéphane P; Abellán Flos, Marta; Hols, Pascal; Lipke, Peter N; Dufrêne, Yves F

2015-02-01

126

Forces in yeast flocculation  

NASA Astrophysics Data System (ADS)

In the baker's yeast Saccharomyces cerevisiae, cell-cell adhesion (``flocculation'') is conferred by a family of lectin-like proteins known as the flocculin (Flo) proteins. Knowledge of the adhesive and mechanical properties of flocculins is important for understanding the mechanisms of yeast adhesion, and may help controlling yeast behaviour in biotechnology. We use single-molecule and single-cell atomic force microscopy (AFM) to explore the nanoscale forces engaged in yeast flocculation, focusing on the role of Flo1 as a prototype of flocculins. Using AFM tips labelled with mannose, we detect single flocculins on Flo1-expressing cells, showing they are widely exposed on the cell surface. When subjected to force, individual Flo1 proteins display two distinct force responses, i.e. weak lectin binding forces and strong unfolding forces reflecting the force-induced extension of hydrophobic tandem repeats. We demonstrate that cell-cell adhesion bonds also involve multiple weak lectin interactions together with strong unfolding forces, both associated with Flo1 molecules. Single-molecule and single-cell data correlate with microscale cell adhesion behaviour, suggesting strongly that Flo1 mechanics is critical for yeast flocculation. These results favour a model in which not only weak lectin-sugar interactions are involved in yeast flocculation but also strong hydrophobic interactions resulting from protein unfolding.

El-Kirat-Chatel, Sofiane; Beaussart, Audrey; Vincent, Stéphane P.; Abellán Flos, Marta; Hols, Pascal; Lipke, Peter N.; Dufrêne, Yves F.

2015-01-01

127

Paludolactone: a new eudesmanolide lactone from Wedelia paludosa DC. (Acmela brasiliensis).  

PubMed

Phytochemical investigation of the whole plant of Wedelia paludosa (Acmela brasiliensis) furnished a new eudesmanolide lactone, named paludolactone (2), in addition to the known eudesmanolide (1), stigmasterol, kaurenoic and oleanolic acids. 1H- and 13C-NMR, and MS spectroscopic and elemental analyses were used for the structural elucidation of these compounds. PMID:15248613

Cechinel Filho, Valdir; Block, Luciana C; Yunes, Rosendo A; Delle Monache, Franco

2004-10-01

128

Variabilidade genética e estimativas de herdabilidade para o caráter germinação em matrizes de Hevea brasiliensis  

Microsoft Academic Search

The present study was carried out to evaluate the genetic variability and genetic parameters of Hevea brasiliensis parent trees for the germination trait. Seeds from thirty parent trees were collected at the Experimental Station, in Votuporanga, SP. The germination tests were carried out at the COMFLORA nursery in Ponta Porã city, following the randomized block design, four replications and ten

Reginaldo Brito da Costa; Paulo de Souza Gonçalves; Lincoln Carlos; Silva de Oliveira; Eduardo José de Arruda; Wagner José Martins

2005-01-01

129

Technological properties of latex and natural rubber of Hevea brasiliensis clones  

Microsoft Academic Search

Rubber industry has increased the requirements for quality and uniformity of natural rubber produced in Brazil. Technological properties of latex and natural rubber of clones GT 1, PB 235, IAN 873 and RRIM 600 (Hevea brasiliensis (Willd. Former Adr. de Juss.) Muell.- Arg) were evaluated by standard methods of the dry rubber content (DRC%), percentage of nitrogen (N%) and percentage

Rogério Manoel Biagi Moreno; Mariselma Ferreira; Paulo de Souza Gonçalves; Luiz Henrique Capparelli Mattoso

2005-01-01

130

IL-13 receptor alpha-2 regulates the immune and functional response to Nippostrongylus brasiliensis infection  

Technology Transfer Automated Retrieval System (TEKTRAN)

IL-13 has a prominent role in host defense against the gastrointestinal nematode, Nippostrongylus brasiliensis; however, the role of IL-13 alpha2 in the immune and functional response to enteric infection is not known. In the current study, we investigated changes in smooth muscle and epithelial ce...

131

Neofusicoccum ribis Associated with Leaf Blight on Rubber (Hevea brasiliensis) in Peninsular Malaysia  

PubMed Central

Hevea brasiliensis is a natural source of rubber and an important plantation tree species in Malaysia. Leaf blight disease caused by Fusicoccum substantially reduces the growth and performance of H. brasiliensis. The aim of this study was to use a combination of both morphological characteristics and molecular data to clarify the taxonomic position of the fungus associated with leaf blight disease. Fusicoccum species were isolated from infected leaves collected from plantations at 3 widely separated locations – Selangor, Perak, and Johor states – in Peninsular Malaysia in 2010. All the isolates were identified according to their conidial patterns and DNA sequences generated from internal transcribed spacers (ITS1 and ITS2), the 5.8S rRNA, and an unknown locus (BotF15) containing microsatellite repeats. Based on taxonomic and sequence data, Neofusicoccum ribis was identified as the main cause of leaf blight disease in H. brasiliensis in commercial plantations in Malaysia. A pathogenicity trial on detached leaves further confirmed that N. ribis causes leaf blight disease. N. ribis is an important leaf pathogen, and its detection in Malaysia has important implications for future planting of H. brasiliensis. PMID:25288924

Nyaka Ngobisa, A. I. C.; Zainal Abidin, M. A.; Wong, M. Y.; Wan Noordin, M. W. D.

2013-01-01

132

Black thread disease, control measures and yield stimulation in Hevea brasiliensis in Liberia  

Microsoft Academic Search

Described are investigations, carried out in 1963 to 1971 in Hevea brasiliensis at the Firestone Plantation at Harbel in Liberia. Studied was the tapping panel disease, black thread, caused by the fungus Phytophthora palmivora. The emphasis of the investigations was on control of the disease with the fungicide captafol (Difolatan). Another line of investigation was yield stimulation with 2,4-D (salts

J. Schreurs

1972-01-01

133

Epidemiology of Ornithodoros brasiliensis (mouro tick) in the southern Brazilian highlands and the description of human and animal retrospective cases of tick parasitism.  

PubMed

Ornithodoros brasiliensis, also known as the "mouro" tick, is an argasid tick found exclusively in the southern Brazilian highlands. O. brasiliensis parasitism is frequently associated with severe symptoms directly induced by the tick bite, a condition compatible with the definition of tick toxicosis. The objectives of this work include (i) the determination of the distribution of O. brasiliensis in farms located in the tick-endemic region, (ii) the description of the characteristics of O. brasiliensis habitats, (iii) the analysis of risk factors associated with O. brasiliensis, and (iv) the retrospective description of cases of human and animal parasitism by O. brasiliensis. Of the 30 farms included in this study, O. brasiliensis was identified on 5 farms (frequency 16.7%), in which several ticks found in high density buried in soil were collected. Information regarding the tick habitats and the local population was recorded. The data indicated that O. brasiliensis feeds on humans, dogs, armadillos (Dasypus hybridus), and possibly skunks (Conepatus chinga). The analysis of risk factors indicated that the presence of house basements with an unpaved (natural soil) floor on farms and insufficient sanitary conditions significantly enhanced the probability of identifying O. brasiliensis. Additionally, we describe retrospectively cases of tick parasitism in 28 humans and 11 dogs including the most common symptoms associated with tick toxicosis. This is the first study concerning O. brasiliensis epidemiology, distribution, and habitat, and the report represents the most comprehensive characterization of Ornithodoros bite-associated toxicosis syndrome. PMID:23238249

Reck, José; Marks, Fernanda S; Guimarães, Jorge A; Termignoni, Carlos; Martins, João Ricardo

2013-02-01

134

Yeast killer toxins and dimorphism.  

PubMed

The differential action of four selected yeast killer toxins on the mycelial and yeast forms of four isolates of the dimorphic fungus Sporothrix schenckii was comparatively evaluated. The results confirmed that the yeast killer phenomenon is present among hyphomycetes and yeasts and that both morphological forms of S. schenckii are susceptible to the action of the same yeast killer toxin. Quantitative differences in the response to the killer action of the mycelial and yeast forms in individual strains were also observed. To avoid retroconversion of the dimorphic forms, we used a modification of the conventional killer system. PMID:2754015

Polonelli, L; Conti, S; Campani, L; Morace, G; Fanti, F

1989-06-01

135

Changes in kinematics and aerodynamics over a range of speeds in Tadarida brasiliensis, the Brazilian free-tailed bat  

PubMed Central

To date, wake measurements using particle image velocimetry (PIV) of bats in flight have studied only three bat species, all fruit and nectar feeders. In this study, we present the first wake structure analysis for an insectivorous bat. Tadarida brasiliensis, the Brazilian free-tailed bat, is an aerial hunter that annually migrates long distances and also differs strikingly from the previously investigated species morphologically. We compare the aerodynamics of T. brasiliensis with those of other, frugivorous bats and with common swifts, Apus apus, a bird with wing morphology, kinematics and flight ecology similar to that of these bats. The comparison reveals that, for the range of speeds evaluated, the cyclical pattern of aerodynamic forces associated with a wingbeat shows more similarities between T. brasiliensis and A. apus than between T. brasiliensis and other frugivorous bats. PMID:22258554

Hubel, Tatjana Y.; Hristov, Nickolay I.; Swartz, Sharon M.; Breuer, Kenneth S.

2012-01-01

136

Functional and structural optimization of the respiratory system of the bat Tadarida brasiliensis (Chiroptera, Molossidae): does airway geometry matter?  

PubMed

We studied structure and function of the respiratory system in the bat Tadarida brasiliensis and compared it with those of two species of rodents, Abrothrix andinus and A. olivaceus. Tadarida brasiliensis had lower resting oxygen consumption, but higher maximum oxygen consumption and aerobic scope, than the rodents. The blood-gas barrier of the bat was thinner and its relative lung size was larger; however, alveolar surface density was similar among the three species. In consequence, T. brasiliensis has an oxygen diffusion capacity two or three times higher than that of the rodents. In Tadarida brasiliensis the characteristics of the lung were accompanied by geometrical changes in the proximal airway, such as high physical optimization as a consequence of small variations in the symmetry and the scaling ratio of the bronchial diameters. These may constitute an efficient way to save energy in respiratory mechanics and are the first report of airway adjustments to decrease entropy generation in bats. PMID:16215224

Canals, Mauricio; Atala, Cristian; Olivares, Ricardo; Guajardo, Francisco; Figueroa, Daniela P; Sabat, Pablo; Rosenmann, Mario

2005-10-01

137

Distributional potential of the Triatoma brasiliensis species complex at present and under scenarios of future climate conditions  

E-print Network

Background The Triatoma brasiliensis complex is a monophyletic group, comprising three species, one of which includes two subspecific taxa, distributed across 12 Brazilian states, in the caatinga and cerrado biomes. Members of the complex...

Costa, Jane; Dornak, L. Lynnette; Almeida, Carlos Eduardo; Peterson, A. Townsend

2014-05-22

138

Mapping Yeast Transcriptional Networks  

PubMed Central

The term “transcriptional network” refers to the mechanism(s) that underlies coordinated expression of genes, typically involving transcription factors (TFs) binding to the promoters of multiple genes, and individual genes controlled by multiple TFs. A multitude of studies in the last two decades have aimed to map and characterize transcriptional networks in the yeast Saccharomyces cerevisiae. We review the methodologies and accomplishments of these studies, as well as challenges we now face. For most yeast TFs, data have been collected on their sequence preferences, in vivo promoter occupancy, and gene expression profiles in deletion mutants. These systematic studies have led to the identification of new regulators of numerous cellular functions and shed light on the overall organization of yeast gene regulation. However, many yeast TFs appear to be inactive under standard laboratory growth conditions, and many of the available data were collected using techniques that have since been improved. Perhaps as a consequence, comprehensive and accurate mapping among TF sequence preferences, promoter binding, and gene expression remains an open challenge. We propose that the time is ripe for renewed systematic efforts toward a complete mapping of yeast transcriptional regulatory mechanisms. PMID:24018767

Hughes, Timothy R.; de Boer, Carl G.

2013-01-01

139

IL13, IL4R?, and Stat6 Are Required for the Expulsion of the Gastrointestinal Nematode Parasite Nippostrongylus brasiliensis  

Microsoft Academic Search

Although IL-4 induces expulsion of the gastrointestinal nematode parasite, Nippostrongylus brasiliensis, from immunodeficient mice, this parasite is expelled normally by IL-4-deficient mice. This apparent paradox is explained by observations that IL-4 receptor ? chain (IL-4R?)-deficient mice and Stat6-deficient mice fail to expel N. brasiliensis, and a specific antagonist for IL-13, another activator of Stat6 through IL-4R?, prevents worm expulsion. Thus,

Joseph F Urban Jr.; Nancy Noben-Trauth; Debra D Donaldson; Kathleen B Madden; Suzanne C Morris; Mary Collins; Fred D Finkelman

1998-01-01

140

Evolutionary history of Ascomyceteous Yeasts  

Technology Transfer Automated Retrieval System (TEKTRAN)

Yeasts are important for many industrial and biotechnological processes and show remarkable diversity despite morphological similarities. We have sequenced the genomes of 20 ascomyceteous yeasts of taxonomic and industrial importance including members of Saccharomycotina and Taphrinomycotina. A comp...

141

Yeast killer systems.  

PubMed Central

The killer phenomenon in yeasts has been revealed to be a multicentric model for molecular biologists, virologists, phytopathologists, epidemiologists, industrial and medical microbiologists, mycologists, and pharmacologists. The surprisingly widespread occurrence of the killer phenomenon among taxonomically unrelated microorganisms, including prokaryotic and eukaryotic pathogens, has engendered a new interest in its biological significance as well as its theoretical and practical applications. The search for therapeutic opportunities by using yeast killer systems has conceptually opened new avenues for the prevention and control of life-threatening fungal diseases through the idiotypic network that is apparently exploited by the immune system in the course of natural infections. In this review, the biology, ecology, epidemiology, therapeutics, serology, and idiotypy of yeast killer systems are discussed. PMID:9227858

Magliani, W; Conti, S; Gerloni, M; Bertolotti, D; Polonelli, L

1997-01-01

142

Virtual Yeast Cell  

NSDL National Science Digital Library

Learning about the various parts of a cell can be tricky business, but this virtual yeast cell offered by The University of Nottingham will come in handy for biology students and science instructors. This learning resource was created to help students in the brewing science program learn about yeast cytology, though just about anyone with an interest in cells will learn something from visiting the site. After entering the interactive cell, visitors can click on different parts of the cell (such as the cytoplasm or the nucleus) in order to learn more about the importance of each one. Visitors should remember that they can also download the virtual yeast cell and use it in the classroom or just with a group of friends.

143

Interspecific interactions involving Neoseiulus californicus (Acari: Phytoseiidae) and Agistemus brasiliensis (Acari: Stigmaeidae) as predators of Brevipalpus phoenicis (Acari: Tenuipalpidae).  

PubMed

Brevipalpus phoenicis (Geijskes) is associated with the transmission of Citrus leprosis which is considered the main viral disease for the Brazilian citrus production. Mites of the families Stigmaeidae and Phytoseiidae coexist in various agricultural crops, often promoting the biological control of pest mites. The aim of this work was to study the interactions of Neoseiulus californicus (McGregor) (Phytoseiidae) and Agistemus brasiliensis Matioli, Ueckermann & Oliveira (Stigmaeidae), in the presence or absence of B. phoenicis. Two experiments were carried out. In the first, a N. californicus female was placed in each leaf disc arena, with eggs of B. phoenicis and A. brasiliensis as food sources. In the second, an A. brasiliensis female was placed in each arena, with eggs of B. phoenicis and N. californicus as food sources. Adults of both predators were able to consume both types of eggs available as food sources, but they fed on considerably higher proportions of B. phoenicis than on eggs of the predator. Eggs of A. brasiliensis were not a suitable food source for N. californicus, which produced only 0.1 egg per female per day when only eggs of that species were present in the experimental unit. The results suggest that eggs of N. californicus were a suitable food source for A. brasiliensis, which oviposited 1.12 eggs per day, when only eggs of N. californicus were provided to the stigmaeid mite. The possible interactions among N. californicus, A. brasiliensis and B. phoenicis in citrus orchards are discussed. PMID:25524512

da Silva, Marcos Zatti; Sato, Mário Eidi; de Oliveira, Carlos Amadeu Leite; Nicastro, Roberto Lomba

2015-03-01

144

Cryopreservation of yeast cultures.  

PubMed

A method is described that allows a wide range of yeast species to be stored in liquid nitrogen while maintaining a high level of viability. Yeast cultures are sealed in commercially available polypropylene straws after having been mixed with a glycerol-based cryoprotectant. Once placed in a secondary cryotube the temperature of the sealed straws is reduced slowly to -30 degrees C in a methanol bath over a period of up to 3 h. The straws are then transferred directly to the liquid nitrogen and placed in a racking system for long-term storage. PMID:18080465

Bond, Chris

2007-01-01

145

Genetics of Yeasts  

NASA Astrophysics Data System (ADS)

The use of yeasts in biotechnology processes dates back to ancient days. Before 7000 BC, beer was produced in Sumeria. Wine was made in Assyria in 3500 BC, and ancient Rome had over 250 bakeries, which were making leavened bread by 100 BC. And milk has been made into Kefyr and Koumiss in Asia for many centuries (Demain, Phaff, & Kurtzman, 1999). However, the importance of yeast in the food and beverage industries was only realized about 1860, when their role in food manufacturing became evident.

Querol, Amparo; Fernández-Espinar, M. Teresa; Belloch, Carmela

146

A common Caatinga cactus, Pilosocereus gounellei, is an important ecotope of wild Triatoma brasiliensis populations in the Jaguaribe valley of northeastern Brazil.  

PubMed

Triatoma brasiliensis is the most important vector of Chagas disease in the Caatinga eco-region of northeastern Brazil. Wild T. brasiliensis populations have been reported only from rocky outcrops. However, this species frequently infests/re-infests houses in rock-free sedimentary lowlands. We therefore hypothesized that it should also occupy other natural ecotopes. We show that a common Caatinga cactus, Pilosocereus gounellei, locally known as xiquexique, often harbors T. brasiliensis breeding colonies apparently associated with rodents (n = 44 cacti, infestation rate = 47.7%, 157 bugs captured). Our findings suggest that infested cacti might be involved in house re-infestation by T. brasiliensis in the Caatinga region. PMID:24710611

Valença-Barbosa, Carolina; Lima, Marli M; Sarquis, Otília; Bezerra, Claudia M; Abad-Franch, Fernando

2014-06-01

147

L-arabinose fermenting yeast  

DOEpatents

An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. A yeast strain engineered to metabolize arabinose through a novel pathway is also disclosed. Methods of producing ethanol include utilizing these modified yeast strains.

Zhang, Min; Singh, Arjun; Suominen, Pirkko; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric

2014-09-23

148

Genome evolution in yeasts  

Microsoft Academic Search

Identifying the mechanisms of eukaryotic genome evolution by comparative genomics is often complicated by the multiplicity of events that have taken place throughout the history of individual lineages, leaving only distorted and superimposed traces in the genome of each living organism. The hemiascomycete yeasts, with their compact genomes, similar lifestyle and distinct sexual and physiological properties, provide a unique opportunity

Bernard Dujon; David Sherman; Gilles Fischer; Pascal Durrens; Serge Casaregola; Ingrid Lafontaine; Jacky de Montigny; Christian Marck; Cécile Neuvéglise; Emmanuel Talla; Nicolas Goffard; Lionel Frangeul; Michel Aigle; Véronique Anthouard; Anna Babour; Valérie Barbe; Stéphanie Barnay; Sylvie Blanchin; Jean-Marie Beckerich; Emmanuelle Beyne; Claudine Bleykasten; Anita Boisramé; Jeanne Boyer; Laurence Cattolico; Fabrice Confanioleri; Antoine de Daruvar; Laurence Despons; Emmanuelle Fabre; Cécile Fairhead; Hélène Ferry-Dumazet; Alexis Groppi; Florence Hantraye; Christophe Hennequin; Nicolas Jauniaux; Philippe Joyet; Rym Kachouri; Alix Kerrest; Romain Koszul; Marc Lemaire; Isabelle Lesur; Laurence Ma; Héloïse Muller; Jean-Marc Nicaud; Macha Nikolski; Sophie Oztas; Odile Ozier-Kalogeropoulos; Stefan Pellenz; Serge Potier; Guy-Franck Richard; Marie-Laure Straub; Audrey Suleau; Dominique Swennen; Fredj Tekaia; Micheline Wésolowski-Louvel; Eric Westhof; Bénédicte Wirth; Maria Zeniou-Meyer; Ivan Zivanovic; Monique Bolotin-Fukuhara; Agnès Thierry; Christiane Bouchier; Bernard Caudron; Claude Scarpelli; Claude Gaillardin; Jean Weissenbach; Patrick Wincker; Jean-Luc Souciet

2004-01-01

149

Chemical genomics in yeast  

PubMed Central

Many drugs have unknown, controversial or multiple mechanisms of action. Four recent 'chemical genomic' studies, using genome-scale collections of yeast gene deletions that were either arrayed or barcoded, have presented complementary approaches to identifying gene-drug and pathway-drug interactions. PMID:15345040

Brenner, Charles

2004-01-01

150

Yeast DNA Extraction  

NSDL National Science Digital Library

This laboratory exercise is designed to show learners how DNA can easily be extracted from yeast using simple materials. Use this experiment to supplement any unit on genetics and to demonstrate how scientists study DNA. Adult supervision is recommended. This resource guide includes tips and suggestions for instructors as well as other DNA extraction experiments and a chart for learners to answer questions.

Lana Hays

2009-01-01

151

Reactive oxygen intermediates metabolizing enzymes in Ancylostoma ceylanicum and Nippostrongylus brasiliensis.  

PubMed

Adult worms of Ancylostoma ceylanicum and Nippostronglyus brasiliensis were found to possess an active system for the detoxification of reactive oxygen intermediates. Xanthine oxidase, which is known to produce superoxide anion, was detected in both the nematode parasites in significant activities. Superoxide anion, thus produced, may quickly be eliminated by superoxide dismutase. Both parasites also exhibited the presence of catalase, peroxidase, and glutathione peroxidase for efficient removal of hydrogen peroxide. Glutathione reductase and glucose-6-phosphate dehydrogenase were, however, detected in low levels of activities. Endowment of A. ceylanicum and N. brasiliensis with these antioxidant enzymes, therefore, enables them to evade the host's effector mechanism for their survival. Superoxide dismutase of both these nematodes showed marked inhibition by KCN and, hence, the enzyme appears to be of copper-zinc type. PMID:2341058

Batra, S; Singh, S P; Gupta, S; Katiyar, J C; Srivastava, V M

1990-01-01

152

Cucullanus bonaerensis n. sp. (Nematoda: Cucullanidae) parasitizing Urophycis brasiliensis (Pisces: Phycidae) from Argentinean waters.  

PubMed

A total of 8 specimens of Urophycis brasiliensis (Kaup, 1858) from waters off Mar del Plata, Argentina (38 degrees 08'S, 57 degrees 32'W), were examined for parasitic nematodes. A new nematode species, Cucullanus bonaerensis n. sp., is described (prevalence 50%, mean intensity 15.5). The new species differs from its congeners in the distribution pattern of caudal papillae (particularly fourth pair) and phasmids, length of the body and spicules, and by the position of the excretory pore (in the posterior third of esophagus). Species of Cucullanus, reported previously as C. heterochrous Rudolphi, 1812, and Cucullanus sp. from U. brasiliensis from Puerto Quequén, Argentina (38 degrees 37'S, 58 degrees 53'W), are considered as members of the new species. PMID:15357074

Lanfranchi, Ana L; Timi, Juan T; Sardella, Norma H

2004-08-01

153

Antifungal activity of fractions and two pure compounds of flowers from Wedelia paludosa (Acmela brasiliensis) (Asteraceae).  

PubMed

Wedelia paludosa (Acmela brasiliensis) (Asteraceae), a traditionally used native Brazilian medicinal plant, showed antifungal activity against dermatophytes in dilution tests. The hexane, dichloromethane and butanol fractions displayed activity against Epidermophyton floccosum, Trichophyton rubrum and Trichophyton mentagrophytes, with minimal inhibitory concentrations between 250 and 1000 microg/mL. Two pure compounds, identified as kaurenoic acid (1) and luteolin (2), also showed activity against these dermatophytes. PMID:12967035

Sartori, M R K; Pretto, J B; Cruz, A B; Bresciani, L F V; Yunes, R A; Sortino, M; Zacchino, S A; Cechinel, V Filho

2003-08-01

154

Seasonal variation of kaurenoic acid, a hypoglycemic diterpene present in Wedelia paludosa (Acmela brasiliensis) (Asteraceae).  

PubMed

We evaluated the variation of the concentration of kaurenoic acid (1), which is a bioactive diterpene, in leaves, flowers, stems and roots from Wedelia paludosa (Acmela brasiliensis) for different seasons using the HRGC/FID method. The results indicated that the concentration of 1 is higher in the roots and stems during the autumn. The pharmacological results suggested that kaurenoic acid is responsible, at least in part, for the hypoglycemic potential detected in this plant. PMID:15241932

Bresciani, Louisiane Faccio V; Yunes, Rosendo Augusto; Bürger, Cristiani; De Oliveira, Luis Eduardo; Bóf, Kauê Leal; Cechinel-Filho, Valdir

2004-01-01

155

Volatile antimicrobial compounds in the pelage of the Mexican free-tailed bat, Tadarida brasiliensis mexicana  

Microsoft Academic Search

Gas chromatography–mass spectrometry (GC–MS) showed that CH2Cl2 extracts of the pelage from the Mexican free-tailed bats, Tadarida brasiliensis mexicana, contained only seven volatile compounds. They include two hydrocarbons, 1-octene and octane; three aldehydes, heptanal, octanal and nonanal; a carboxylic acid, nonanoic acid; and urea. It is likely that nonanal, at an average concentration 0.62?g\\/mg hair, and the two homologues, heptanal

William F. Wood; Joseph M. Szewczak

2007-01-01

156

Dietary energetics of the insectivorous Mexican free-tailed bat ( Tadarida brasiliensis ) during pregnancy and lactation  

Microsoft Academic Search

Stomach content analysis of 20 pregnant (x body mass=13.4 g) and 18 lactating (x body mass=11.5 g) female Tadarida brasiliensis revealed that the diet, expressed as percent volume, consists largely of lepidopterans, coleopterans, hymenopterans, and dipterans, in decreasing order of importance. We found no significant difference in the diet of pregnant and lactating females when expressed as percent volume. However,

T. H. Kunz; J. O. Whitaker Jr; M. D. Wadanoli

1995-01-01

157

Population growth of Mexican free-tailed bats ( Tadarida brasiliensis mexicana ) predates human agricultural activity  

Microsoft Academic Search

Background  Human activities, such as agriculture, hunting, and habitat modification, exert a significant effect on native species. Although\\u000a many species have suffered population declines, increased population fragmentation, or even extinction in connection with\\u000a these human impacts, others seem to have benefitted from human modification of their habitat. Here we examine whether population\\u000a growth in an insectivorous bat (Tadarida brasiliensis mexicana) can

Amy L Russell; Murray P Cox; Veronica A Brown; Gary F McCracken

2011-01-01

158

Feline sporotrichosis due to Sporothrix brasiliensis : an emerging animal infection in São Paulo, Brazil.  

PubMed

BackgroundSporotrichosis is a mycotic infectious disease that is generally acquired by traumatic inoculation of contaminated materials especially from plant debris or through bites and scratches from diseased animals, such as domestic cats. It affects the skin, lymphatic system, and other organs in the warm-blooded host. Etiological agents are embedded in the plant-associated order Ophiostomatales. With essential differences between possible outbreak sources and ecological niche, host-environment interactions are classic determinants of risk factors for disease acquisition. Sporotrichosis outbreaks with zoonotic transmission, such as those that are ongoing in southern and southeastern Brazil, have highlighted the threat of cross-species pathogen transmission. Sporothrix brasiliensis has emerged as a human threat owing to the intimate contact pattern between diseased cats and humans in endemic areas.ResultsWe describe the recent emergence of feline sporotrichosis in the metropolitan region of São Paulo, Brazil, with an overwhelming occurrence of S. brasiliensis as the etiological agent. A phylogenetic and a haplotype approach were used to investigate the origin of this epidemic and the impact of feline transmission on genetic diversity. During the last 3-year period, 163 cases of feline sporotrichosis were reported in São Paulo with proven S. brasiliensis culture. The haplotype diversity of feline S. brasiliensis isolates revealed the expansion of a clonal population with low genetic diversity. Haplotype analysis confirmed that isolates from São Paulo shared the haplotype originated in the long-lasting outbreak of cat-transmitted sporotrichosis in Rio de Janeiro, which differed from the haplotype circulating in the Rio Grande do Sul epidemic.ConclusionsThe fast spread of sporotrichosis in a short period of time highlights the potential for outbreaks and suggests that the mycosis may affect an urban population with a high concentration of susceptible felines. The feline sporotrichosis epidemic shows no signs of slowing, and this epidemiological pattern may require specific public health strategies to control future outbreaks. PMID:25407096

Montenegro, Hildebrando; Rodrigues, Anderson; Dias, Maria; da Silva, Elisabete; Bernardi, Fernanda; de Camargo, Zoilo

2014-11-19

159

Cryopreservation of nucellar cells of navel orange ( Citrus sinensis Osb. var. brasiliensis Tanaka) by vitrification  

Microsoft Academic Search

The nucellar cells of navel orange(Citrus sinensis Osb. var. brasiliensis Tanaka) were successfully cryopreserved by vitrification. In this method, cells were sufficiently dehydrated with highly concentrated cryoprotective solution(PVS2) prior to direct plunge in liquid nitrogen. The PVS2 contains(w\\/v) 30% glycerol, 15% ethylene glycol and 15% DMSO in Murashige-Tucker medium(MT) containing 0.15 M sucrose. Cells were treated with 60% PVS2 at

A. Sakai; S. Kobayashi; I. Oiyama

1990-01-01

160

The effect of anaerobiosis on adenosine triphosphate levels in larval Nippostrongylus brasiliensis and Haemonchus contortus  

Microsoft Academic Search

The adenosine triphosphate (ATP) content of the pre-parasitic stages ofNippostrongylus brasiliensis, Haemonchus contortus (L1, L2 and L3) and the adults of the free-living nematode,Panagrellus redivivus, have been measured by bioluminescent photometry in aerated or nearanoxic conditions. The ATP content of the L1 and L2 stages of both parasitic species was unaltered by a lack of oxygen over a 90-min period.

C. O. E. Onwuliri

1984-01-01

161

Cross-species characterisation of polymorphic microsatellite loci in the giant otter (Pteronura brasiliensis).  

PubMed

Nineteen microsatellite loci developed for the Eurasian otter (Lutra lutra) and 15 loci developed for the North American river otter (Lontra canadensis) were tested for ease of amplification and degree of polymorphism on a set of 20 giant otter (Pteronura brasiliensis) faecal samples from the Bolivian Amazon basin. Nineteen loci amplified consistently well, with polymorphisms ranging from two to nine alleles and observed heterozygosity ranging from 0.15 to 0.85. PMID:21564666

Pickles, Robert S A; Groombridge, James J; Rojas, Veronica D Zambrana; Jordan, William C

2009-01-01

162

Ecotope effect in Triatoma brasiliensis (Hemiptera: Reduviidae) suggests phenotypic plasticity rather than adaptation.  

PubMed

Triatoma brasiliensis (Hemiptera: Reduviidae) is an important vector of Chagas' disease in both sylvatic and peridomestic ecotopes. Discriminating between these populations of Triatominae has been proposed as a means of investigating re-infestation rates of human dwellings. Geometric morphometrics have been widely applied in the study of Triatominae polymorphisms at species and population levels. This study characterizes morphometric differences between sylvatic and peridomestic populations, as well as between sexes in T. brasiliensis specimens from Jaguaruana, Ceará, in northeastern Brazil. No differences in either the shape or size of the cephalic capsule were apparent between sexes or ecotopes. However, the wings showed differentiation in shape and size. Sexual dimorphism was detected, with females presenting significantly higher values and conformations. Size differentiation was also evident, with sylvatic specimens being generally larger than peridomestic examples. These results indicate that differences in the wings of T. brasiliensis may be related to the existence of phenotypic plasticity, and variations in size and shape may be associated with different ecotopes, possibly as a result of conditions in each micro-habitat, such as temperature, relative humidity, food supply and density. PMID:22985051

Batista, V S P; Fernandes, F A; Cordeiro-Estrela, P; Sarquis, O; Lima, M M

2013-09-01

163

Bark harvesting systems of Drimys brasiliensis Miers in the Brazilian Atlantic rainforest.  

PubMed

Drimys brasiliensis Miers, locally known as cataia or casca-de-anta, is a native tree species of the Atlantic Rainforest. Its bark is harvested from natural populations. This study examined the recovery capacity of the bark of D. brasiliensis under different bark harvesting methods, as well as the influence of these approaches on its population dynamics and reproductive biology. While none of these treatments resulted in changes in phenological behavior or the rate of increase of diameter at breast height and tree height, the removal of wider bark strips resulted in lower rates of bark recovery and higher rates of insect attack and diseases. Accordingly, the results recommend using strips of bark 2 cm wide and 2 m long, with 4 cm between strips, for effective rates of bark regrowth and for lower susceptibility to insect attack and diseases. From these studies, we concluded that D. brasiliensis has a high potential for sustainable management of its natural populations, demonstrating the possibility of generating an important supplementary income for farmers and contributing to the use and conservation of the Atlantic Rainforest. PMID:25119732

Mariot, Alexandre; Mantovani, Adelar; Reis, Maurício S dos

2014-09-01

164

Morphometry, Bite-Force, and Paleobiology of the Late Miocene Caiman Purussaurus brasiliensis  

PubMed Central

Purussaurus brasiliensis thrived in the northwestern portion of South America during the Late Miocene. Although substantial material has been recovered since its early discovery, this fossil crocodilian can still be considered as very poorly understood. In the present work, we used regression equations based on modern crocodilians to present novel details about the morphometry, bite-force and paleobiology of this species. According to our results, an adult Purussaurus brasiliensis was estimated to reach around 12.5 m in length, weighing around 8.4 metric tons, with a mean daily food intake of 40.6 kg. It was capable of generating sustained bite forces of 69,000 N (around 7 metric tons-force). The extreme size and strength reached by this animal seems to have allowed it to include a wide range of prey in its diet, making it a top predator in its ecosystem. As an adult, it would have preyed upon large to very large vertebrates, and, being unmatched by any other carnivore, it avoided competition. The evolution of a large body size granted P. brasiliensis many advantages, but it may also have led to its vulnerability. The constantly changing environment on a large geological scale may have reduced its long-term survival, favoring smaller species more resilient to ecological shifts. PMID:25689140

Aureliano, Tito; Ghilardi, Aline M.; Guilherme, Edson; Souza-Filho, Jonas P.; Cavalcanti, Mauro; Riff, Douglas

2015-01-01

165

Morphometry, Bite-Force, and Paleobiology of the Late Miocene Caiman Purussaurus brasiliensis.  

PubMed

Purussaurus brasiliensis thrived in the northwestern portion of South America during the Late Miocene. Although substantial material has been recovered since its early discovery, this fossil crocodilian can still be considered as very poorly understood. In the present work, we used regression equations based on modern crocodilians to present novel details about the morphometry, bite-force and paleobiology of this species. According to our results, an adult Purussaurus brasiliensis was estimated to reach around 12.5 m in length, weighing around 8.4 metric tons, with a mean daily food intake of 40.6 kg. It was capable of generating sustained bite forces of 69,000 N (around 7 metric tons-force). The extreme size and strength reached by this animal seems to have allowed it to include a wide range of prey in its diet, making it a top predator in its ecosystem. As an adult, it would have preyed upon large to very large vertebrates, and, being unmatched by any other carnivore, it avoided competition. The evolution of a large body size granted P. brasiliensis many advantages, but it may also have led to its vulnerability. The constantly changing environment on a large geological scale may have reduced its long-term survival, favoring smaller species more resilient to ecological shifts. PMID:25689140

Aureliano, Tito; Ghilardi, Aline M; Guilherme, Edson; Souza-Filho, Jonas P; Cavalcanti, Mauro; Riff, Douglas

2015-01-01

166

Extracellular Polysaccharides Produced by Yeasts and Yeast-Like Fungi  

NASA Astrophysics Data System (ADS)

Several yeasts and yeast-like fungi are known to produce extracellular polysaccharides. Most of these contain D-mannose, either alone or in combination with other sugars or phosphate. A large chemical and structural variability is found between yeast species and even among different strains. The types of polymers that are synthesized can be chemically characterized as mannans, glucans, phosphoman-nans, galactomannans, glucomannans and glucuronoxylomannans. Despite these differences, almost all of the yeast exopolysaccharides display some sort of biological activity. Some of them have already applications in chemistry, pharmacy, cosmetics or as probiotic. Furthermore, some yeast exopolysaccharides, such as pullulan, exhibit specific physico-chemical and rheological properties, making them useful in a wide range of technical applications. A survey is given here of the production, the characteristics and the application potential of currently well studied yeast extracellular polysaccharides.

van Bogaert, Inge N. A.; de Maeseneire, Sofie L.; Vandamme, Erick J.

167

Extracellular Polysaccharides Produced by Yeasts and YeastLike Fungi  

Microsoft Academic Search

Several yeasts and yeast-like fungi are known to produce extracellular polysaccharides. Most of these contain D-mannose, either\\u000a alone or in combination with other sugars or phosphate. A large chemical and structural variability is found between yeast\\u000a species and even among different strains. The types of polymers that are synthesized can be chemically characterized as mannans,\\u000a glucans, phosphoman-nans, galactomannans, glucomannans and

Inge N. A. Bogaert; Sofie L. Maeseneire; Erick J. Vandamme

168

Extracellular Polysaccharides Produced by Yeasts and YeastLike Fungi  

Microsoft Academic Search

Several yeasts and yeast-like fungi are known to produce extracellular polysaccharides. Most of these contain D-mannose, either alone or in combination with other sugars or phosphate. A large chemical and structural variability is found between yeast species and even among different strains. The types of polymers that are synthesized can be chemically characterized as mannans, glucans, phosphoman-nans, galactomannans, glucomannans and

Inge N. A. van Bogaert; Sofie L. de Maeseneire; Erick J. Vandamme

2009-01-01

169

Ornithodoros brasiliensis (mouro tick) salivary gland homogenates inhibit in vivo wound healing and in vitro endothelial cell proliferation.  

PubMed

Ornithodoros brasiliensis is a nidicolous tick only found in the southern Brazilian highlands region. O. brasiliensis parasitism is frequently associated with toxicosis syndrome, which can lead to severe reactions, ranging from local pruritus and pain to systemic disturbances both in humans and dogs. One of the most frequent findings associated with an O. brasiliensis bite is a slow healing lesion at the site of tick attachment, which can take several weeks to heal. This work tested the hypothesis that an O. brasiliensis salivary gland homogenate is able to modulate the skin wound-healing process in vivo, using a model of excisional skin lesion in rats, which are divided into two groups: (1) control group and (2) treated group, which topically received salivary gland homogenate equivalent to the protein amount of one whole salivary gland (?5 ?g protein). The hypothesis that O. brasiliensis salivary gland homogenates interfere with endothelial cell proliferation, a key role phenomenon in wound healing, was also tested. O. brasiliensis salivary gland homogenates significantly delay skin wound healing. The time to full healing of skin lesions in control rats was 15 days, contrasting with 24 days in rats topically treated with O. brasiliensis salivary gland homogenates. The calculated HT50 (healing time to recover 50% of the wound area) for control groups was 3.6 days (95% CI, 3.2-3.9) and for salivary gland treated rats was 7.7 days (95% CI, 7.0-8.4). Salivary gland homogenates have a strong cytotoxic activity on cultured endothelial cells (LC50, 13.6 mg/ml). Also, at sublethal concentrations (?3 mg/ml), salivary gland homogenates have a remarkable anti-proliferative activity (IC50 0.7 mg/ml) on endothelial cells, equivalent to ?0.03 salivary gland pairs, an activity which seems to be much greater than reported for any other tick species. This is the first report about the biological activities of O. brasiliensis salivary compounds and provides the first in vivo evidence to support the concept of wound-healing modulation by tick salivary secretions. Results shown here contribute to an understanding of O. brasiliensis tick toxicosis syndrome, and also increase our knowledge of tick salivary bioactive compounds. PMID:23397378

Reck, José; Marks, Fernanda S; Termignoni, Carlos; Guimarães, Jorge A; Martins, João Ricardo

2013-04-01

170

Xylose fermentation by yeasts  

Microsoft Academic Search

Xylose reductase from the xylose-fermenting yeastPichia stipitis was purified to electrophoretic homogeneity via ion-exchange, gel and affinity chromatography. At physiological pH values the thermodynamic equilibrium constant was determined to be 0.575x1010 (l·mol-1). Product inhibiton studies are reported which clearly show that the kinetic mechanism of the xylose reductase is ordered-bi-bi with isomerisation of a stable enzyme form.

Manfred Rizzi; Petra Erlemann; Ngoc-Anh Bui-Thanh; Hanswerner Dellweg

1988-01-01

171

Mammalian Homology to Yeast  

NSDL National Science Digital Library

This site allows researchers to retrieve a yeast-against-mammal Basic Local Alignment Search Tool (BLAST) report by entering a gene or ORF name into a search function. The supporting data were first summarized in a recent Science article which is provided via a link to the journal (Science, 22 July 1997; Issue 277: p.1259). Steve Chervitz of Stanford University maintains this site.

1997-01-01

172

Tumor necrosis factor and macrophage activation are important in clearance of Nocardia brasiliensis from the livers and spleens of mice.  

PubMed

The roles of tumor necrosis factor (TNF) and macrophage activation in clearance of Nocardia brasiliensis from BALB/c mouse livers and spleens were evaluated. TNF activity was detectable in sera from animals at all stages of infection. Treatment of infected mice with an antiserum against TNF significantly enhanced the experimental infection as judged by enumeration of CFU in the spleens and livers of infected mice. In another set of experiments, a population of activated macrophages from the peritoneal cavities of N. brasiliensis-infected mice was studied by using a cytostatic assay. The observed cytotoxic activity of these activated macrophages against L929 cells was mediated by TNF, since this activity was inhibited by anti-TNF antiserum treatment. The level of TNF activity generated in vitro in the presence of lipopolysaccharide (LPS) by peritoneal macrophages from infected mice was higher than that of adherent peritoneal cells obtained from normal mice after challenge with LPS. When the nocardiacidal activity of peritoneal cells from N. brasiliensis-infected mice was estimated in vitro, a significant decrease in the number of CFU recovered was observed. Moreover, nocardiacidal activity of peritoneal cells obtained from N. brasiliensis-infected mice previously treated with anti-TNF antiserum was significantly reduced compared with the activity of cells obtained from infected mice previously treated with normal rabbit serum and that of cells from uninfected mice. These data suggest a role for TNF in resistance to N. brasiliensis infection. PMID:1500164

Silva, C L; Faccioli, L H

1992-09-01

173

Cross-mating experiments detect reproductive compatibility between Triatoma sherlocki and other members of the Triatoma brasiliensis species complex.  

PubMed

Phylogenetic approaches based on mitochondrial DNA variation (fragments of Cyt B and 16S ribosomal RNA) have revealed Triatoma sherlocki as the most recent species addition to the Triatoma brasiliensis species complex; a monophyletic group which includes T. brasiliensis, Triatoma melanica, and Triatoma juazeirensis. T. sherlocki is the most differentiated among all species of this complex: it is unable to fly, possesses longer legs than the other members, and has reddish tonality in some parts of its exochorion. We question whether these species are reproductively compatible because of this pronounced morphological differentiation, and therefore, we present a series of cross breeding experiments that test compatibility between T. sherlocki and other members of the T. brasiliensis complex. We extended our analyses to include crosses between T. sherlocki and Triatoma lenti, because the latter has been suggested as a possible member of this complex. T. sherlocki male×T. lenti female pairs failed to produce hybrids. All other crosses of T. sherlocki and members of T. brasiliensis species complex, as well as backcrosses, produced viable offspring through the third generation. This study stresses the importance of searching for the features that may isolate members of the T. brasiliensis species complex. PMID:23850508

Correia, Nathália; Almeida, Carlos E; Lima-Neiva, Vanessa; Gumiel, Márcia; Dornak, L Lynnette; Lima, Marli M; Medeiros, Lívia M O; Mendonça, Vagner J; da Rosa, João A; Costa, Jane

2013-10-01

174

Glutathione Production in Yeast  

NASA Astrophysics Data System (ADS)

Glutathione, ? -glutamyl-cysteinyl-glycine, is the most abundant non-protein thiol found in almost all eukaryotic cells (and in some prokaryotes). The tripeptide, which is synthesized non-ribosomally by the consecutive action of two soluble enzymes, is needed for carrying out numerous functions in the cell, most important of which is the maintenance of the redox buffer. The cycle of glutathione biosynthesis and degradation forms part of the ? -glutamyl cycle in most organisms although the latter half of the pathway has not been demonstrated in yeasts. Our current understanding of how glutathione levels are controlled at different levels in the cell is described. Several different routes and processes have been attempted to increase commercial production of glutathione using both yeast and bacteria. In this article we discuss the history of glutathione production in yeast. The current bottlenecks for increased glutathione production are presented based on our current understanding of the regulation of glutathione homeostasis, and possible strategies for overcoming these limitations for further enhancing and improving glutathione production are discussed

Bachhawat, Anand K.; Ganguli, Dwaipayan; Kaur, Jaspreet; Kasturia, Neha; Thakur, Anil; Kaur, Hardeep; Kumar, Akhilesh; Yadav, Amit

175

Epidemiological and biological aspects on Ornithodoros brasiliensis (mouro tick), an argasidae tick only found on the highlands region of Rio Grande do Sul state, southern Brazil  

Technology Transfer Automated Retrieval System (TEKTRAN)

The soft tick Ornithodoros brasiliensis (Acari: Argasidae) is present in farms along the highlands of Rio Grande do Sul state in southern Brazil. Reports of human parasitism by O. brasiliensis drew the attention of local health authorities. A preliminary epidemiological survey was conducted to ident...

176

Pulmonary infection in two sympatric lizards, Mabuya arajara (Scincidae) and Anolis brasiliensis (Polychrotidae) from a cloud forest in Chapada do Araripe, Ceará, Northeastern Brazil.  

PubMed

The parameters of infection by lung parasites from two sympatric lizards, Mabuya arajara and Anolis brasiliensis, from the Atlantic Rainforest of the lower slope of Chapada do Araripe in Northeastern Brazil were analyzed between September, 2009 and July, 2010. A total of 202 lizards were collected. 125 specimens were from Mabuya arajara and 77 from Anolis brasiliensis. M. arajara was infected by the pentastomid Raillietiella mottae while A. brasiliensis was infected by the nematode Rhabdias sp., with an overall prevalence of 1.6% and 28.6%, respectively. The mean intensity of infection by Rhabdias sp. was 3.63 ± 2.58 (range 1-15). The body size and sex of lizards did not influence the intensity of infection by Rhabdias sp. The overall prevalence was also not different between males and females hosts in A. brasiliensis. Both Anolis brasiliensis and Mabuya arajara represent a new host to Rhabdias sp. and Raillietiella mottae, respectively. PMID:23295524

Ribeiro, S C; Ferreira, F S; Brito, S V; Teles, D A; Ávila, R W; Almeida, W O; Anjos, L A; Guarnieri, M C

2012-11-01

177

Growth and mortalities of the pink-shrimp Farfantepenaeus brasiliensis Latreille, 1970 and F. paulensis Pérez-Farfante 1967 in Southeast Brazil.  

PubMed

From July, 1999 until July, 2001 data from the pink-shrimp Farfantepenaeus brasiliensis Latreille, 1970 and F. paulensis Pérez-Farfante, 1967 fishery were collected from trawling by the fishing fleet based in Santos/Guarujá-SP. Growth and mortalities of these species were studied. F. brasiliensis and F. paulensis have longevity of 2 years and growth estimates of L Infinity = 29.0 cm and k = 1.24 year-1 for F. brasiliensis and L Infinity = 27.5 cm and k = 1.34 year-1 for F. paulensis. Females reach bigger lengths than males in both species. Natural mortalities (M) were 1.80 and 1.90 year-1 and fishing mortalities (F) were 4.7 and 6.8 year-1 for F. brasiliensis and F. paulensis, respectively. Survival rates are S = 0.15% and 0.02% for F. brasiliensis and F. paulensis, respectively, which are usually low values for shrimps. PMID:16862308

Leite, N O; Petrere, M

2006-05-01

178

21 CFR 172.896 - Dried yeasts.  

Code of Federal Regulations, 2011 CFR

...ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis ) and dried torula yeast (Candida utilis ) may be safely used in food...

2011-04-01

179

21 CFR 172.896 - Dried yeasts.  

Code of Federal Regulations, 2012 CFR

...ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis ) and dried torula yeast (Candida utilis ) may be safely used in food...

2012-04-01

180

21 CFR 172.896 - Dried yeasts.  

Code of Federal Regulations, 2014 CFR

...ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis ) and dried torula yeast (Candida utilis ) may be safely used in food...

2014-04-01

181

21 CFR 172.896 - Dried yeasts.  

Code of Federal Regulations, 2010 CFR

...ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis ) and dried torula yeast (Candida utilis ) may be safely used in food...

2010-04-01

182

21 CFR 172.896 - Dried yeasts.  

Code of Federal Regulations, 2013 CFR

...ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.896 Dried yeasts. Dried yeast (Saccharomyces cerevisiae and Saccharomyces fragilis ) and dried torula yeast (Candida utilis ) may be safely used in food...

2013-04-01

183

Differences in Cell Morphometry, Cell Wall Topography and Gp70 Expression Correlate with the Virulence of Sporothrix brasiliensis Clinical Isolates  

PubMed Central

Sporotrichosis is a chronic infectious disease affecting both humans and animals. For many years, this subcutaneous mycosis had been attributed to a single etiological agent; however, it is now known that this taxon consists of a complex of at least four pathogenic species, including Sporothrix schenckii and Sporothrix brasiliensis. Gp70 was previously shown to be an important antigen and adhesin expressed on the fungal cell surface and may have a key role in immunomodulation and host response. The aim of this work was to study the virulence, morphometry, cell surface topology and gp70 expression of clinical isolates of S. brasiliensis compared with two reference strains of S. schenckii. Several clinical isolates related to severe human cases or associated with the Brazilian zoonotic outbreak of sporotrichosis were genotyped and clustered as S. brasiliensis. Interestingly, in a murine subcutaneous model of sporotrichosis, these isolates showed a higher virulence profile compared with S. schenckii. A single S. brasiliensis isolate from an HIV-positive patient not only showed lower virulence but also presented differences in cell morphometry, cell wall topography and abundant gp70 expression compared with the virulent isolates. In contrast, the highly virulent S. brasiliensis isolates showed reduced levels of cell wall gp70. These observations were confirmed by the topographical location of the gp70 antigen using immunoelectromicroscopy in both species. In addition, the gp70 molecule was sequenced and identified using mass spectrometry, and the sequenced peptides were aligned into predicted proteins using Blastp with the S. schenckii and S. brasiliensis genomes. PMID:24116065

Castro, Rafaela A.; Kubitschek-Barreira, Paula H.; Teixeira, Pedro A. C.; Sanches, Glenda F.; Teixeira, Marcus M.; Quintella, Leonardo P.; Almeida, Sandro R.; Costa, Rosane O.; Camargo, Zoilo P.; Felipe, Maria S. S.; de Souza, Wanderley; Lopes-Bezerra, Leila M.

2013-01-01

184

Diet and helminths of Enyalius brasiliensis (Lacertilia, Iguania, Leiosauridae) in an Atlantic Rainforest remnant in southeastern Brazil.  

PubMed

Our study aimed to add information about the diet and endoparasites of Enyalius brasiliensis from an Atlantic Rainforest remnant in the state of Rio de Janeiro, southeastern Brazil. Regarding diet, E. brasiliensis consumed arthropods, with caterpillars and beetles being the most important preys. Regarding helminth parasites, overall prevalence was low (9.5%), with 238 nematodes of the genus Physaloptera found in the stomach of one specimen and one nematode of the genus Rhabdias inside the lung of another. Our results corroborate the observations of previous studies that indicate that lizards of the genus Enyalius tend to feed mainly on relatively large-bodied arthropods and to harbour depauperate endoparasite fauna. PMID:25055102

Dorigo, T A; Maia-Carneiro, T; Almeida-Gomes, M; Siqueira, C C; Vrcibradic, D; Van Sluys, M; Rocha, C F D

2014-02-01

185

First report on the diagnosis and treatment of encephalic and urinary paracoccidioidomycosis in a cat.  

PubMed

A male Persian cat was presented with persistent fever, anorexia, weakness, hypopyon, nystagmus, and intention tremors. The hemogram showed severe neutropenia and laboratory analysis on cerebrospinal fluid (CSF) smears revealed abundant yeast cells compatible with Paracoccidioides brasiliensis. Urinalysis demonstrated persistent funguria and an increased urine protein-to-creatinine ratio (UPC) in addition to mild azotemia. Long-term therapy with oral fluconazole was effective in controlling the nervous system signs. Funguria was resolved with subcutaneous administration of diluted amphotericin B in a large volume of saline solution for a period of 12 weeks during the second year after initial diagnosis. Throughout 5 years of treatment, no adverse effects were observed and tolerance to the drugs was normal. Due to development of progressive uremic syndrome the animal was euthanased. To the best of our knowledge, this report is the first clinical case described of a nervous and urinary system infection caused by the P brasiliensis in a cat. PMID:20471880

Gonzalez, Juan F; Montiel, Nestor A; Maass, Rodrigo L

2010-08-01

186

Simulating Population Genetics of Pathogen Vectors in Changing Landscapes: Guidelines and Application with Triatoma brasiliensis  

PubMed Central

Background Understanding the mechanisms that influence the population dynamics and spatial genetic structure of the vectors of pathogens infecting humans is a central issue in tropical epidemiology. In view of the rapid changes in the features of landscape pathogen vectors live in, this issue requires new methods that consider both natural and human systems and their interactions. In this context, individual-based model (IBM) simulations represent powerful yet poorly developed approaches to explore the response of pathogen vectors in heterogeneous social-ecological systems, especially when field experiments cannot be performed. Methodology/Principal Findings We first present guidelines for the use of a spatially explicit IBM, to simulate population genetics of pathogen vectors in changing landscapes. We then applied our model with Triatoma brasiliensis, originally restricted to sylvatic habitats and now found in peridomestic and domestic habitats, posing as the most important Trypanosoma cruzi vector in Northeastern Brazil. We focused on the effects of vector migration rate, maximum dispersal distance and attraction by domestic habitat on T. brasiliensis population dynamics and spatial genetic structure. Optimized for T. brasiliensis using field data pairwise fixation index (FST) from microsatellite loci, our simulations confirmed the importance of these three variables to understand vector genetic structure at the landscape level. We then ran prospective scenarios accounting for land-use change (deforestation and urbanization), which revealed that human-induced land-use change favored higher genetic diversity among sampling points. Conclusions/Significance Our work shows that mechanistic models may be useful tools to link observed patterns with processes involved in the population genetics of tropical pathogen vectors in heterogeneous social-ecological landscapes. Our hope is that our study may provide a testable and applicable modeling framework to a broad community of epidemiologists for formulating scenarios of landscape change consequences on vector dynamics, with potential implications for their surveillance and control. PMID:25102068

Rebaudo, Francois; Costa, Jane; Almeida, Carlos E.; Silvain, Jean-Francois; Harry, Myriam; Dangles, Olivier

2014-01-01

187

A Cross-Reactive Monoclonal Antibody to Nematode Haemoglobin Enhances Protective Immune Responses to Nippostrongylus brasiliensis  

PubMed Central

Background Nematode secreted haemoglobins have unusually high affinity for oxygen and possess nitric oxide deoxygenase, and catalase activity thought to be important in protection against host immune responses to infection. In this study, we generated a monoclonal antibody (48Eg) against haemoglobin of the nematode Anisakis pegreffii, and aimed to characterize cross-reactivity of 4E8g against haemoglobins of different nematodes and its potential to mediate protective immunity against a murine hookworm infection. Methodology/Principal Findings Immunoprecipitation was used to isolate the 4E8g-binding antigen in Anisakis and Ascaris extracts, which were identified as haemoglobins by peptide mass fingerprinting and MS/MS. Immunological cross-reactivity was also demonstrated with haemoglobin of the rodent hookworm N. brasiliensis. Immunogenicity of nematode haemoglobin in mice and humans was tested by immunoblotting. Anisakis haemoglobin was recognized by IgG and IgE antibodies of Anisakis-infected mice, while Ascaris haemoglobin was recognized by IgG but not IgE antibodies in mouse and human sera. Sequencing of Anisakis haemoglobin revealed high similarity to haemoglobin of a related marine nematode, Psuedoterranova decipiens, which lacks the four –HKEE repeats of Ascaris haemoglobin important in octamer assembly. The localization of haemoglobin in the different parasites was examined by immunohistochemistry and associated with the excretory-secretary ducts in Anisakis, Ascaris and N. brasiliensis. Anisakis haemoglobin was strongly expressed in the L3 stage, unlike Ascaris haemoglobin, which is reportedly mainly expressed in adult worms. Passive immunization of mice with 4E8g prior to infection with N. brasiliensis enhanced protective Th2 immunity and led to a significant decrease in worm burdens. Conclusion The monoclonal antibody 4E8g targets haemoglobin in broadly equivalent anatomical locations in parasitic nematodes and enhances host immunity to a hookworm infection. PMID:24009787

Nieuwenhuizen, Natalie E.; Meter, Jeanne M.; Horsnell, William G.; Hoving, J. Claire; Fick, Lizette; Sharp, Michael F.; Darby, Matthew G.; Parihar, Suraj P.; Brombacher, Frank; Lopata, Andreas L.

2013-01-01

188

BIOSYNTHESIS OF YEAST CAROTENOIDS  

PubMed Central

Simpson, Kenneth L. (University of California, Davis), T. O. M. Nakayama, and C. O. Chichester. Biosynthesis of yeast carotenoids. J. Bacteriol. 88:1688–1694. 1964.—The biosynthesis of carotenoids was followed in Rhodotorula glutinis and in a new strain, 62-506. The treatment of the growing cultures by methylheptenone, or ionone, vapors permitted observations of the intermediates in the biosynthetic pathway. On the basis of concentration changes and accumulation in blocked pathways, the sequence of carotenoid formation is postulated as phytoene, phytofluene, ?-carotene, neurosporene, ?-zeacarotene, ?-carotene, torulin, a C40 aldehyde, and torularhodin. Torulin and torularhodin were established as the main carotenoids of 62-506. PMID:14240958

Simpson, Kenneth L.; Nakayama, T. O. M.; Chichester, C. O.

1964-01-01

189

Production of Food Grade Yeasts  

Microsoft Academic Search

Summary Yeasts have been known to humans for thousands of years as they have been used in traditional fermentation processes like wine, beer and bread making. Today, yeasts are also used as alternative sources of high nutritional value proteins, enzymes and vitamins, and have numerous applications in the health food industry as food additives, conditioners and flavouring agents, for the

Argyro Bekatorou; Costas Psarianos; Athanasios A. Koutinas

2006-01-01

190

Yeasts from ips sexdentatus (scolytidae)  

Microsoft Academic Search

Yeasts from the digestive tract of Ips sexdentatus were isolated. Four strains, representing the different identified yeast species, were chosen. Their enzymatic activity on oligosaccharides, heterosides and polysaccharides was measured. Moreover, we showed that they excrete some B group vitamins which are necessary for the insect, unable to synthesize them.

Marie-Claire Pignal; C. Chararas; Michèle Bourgeay-Causse

1988-01-01

191

New and emerging yeast pathogens.  

PubMed Central

The most common yeast species that act as agents of human disease are Candida albicans, Candida tropicalis, Candida glabrata, Candida parapsilosis, and Cryptococcus neoformans. The incidence of infections by other yeasts has increased during the past decade. The most evident emerging pathogens are Malassezia furfur, Trichosporon beigelii, Rhodotorula species, Hansenula anomala, Candida lusitaniae, and Candida krusei. Organisms once considered environmental contaminants or only industrially important, such as Candida utilis and Candida lipolytica, have now been implicated as agents of fungemia, onychomycosis, and systemic disease. The unusual yeasts primarily infect immunocompromised patients, newborns, and the elderly. The role of central venous catheter removal and antifungal therapy in patient management is controversial. The antibiograms of the unusual yeasts range from resistant to the most recent azoles and amphotericin B to highly susceptible to all antifungal agents. Current routine methods for yeast identification may be insufficient to identify the unusual yeasts within 2 days after isolation. The recognition of unusual yeasts as agents of sometimes life-threatening infection and their unpredictable antifungal susceptibilities increase the burden on the clinical mycology laboratory to pursue complete species identification and MIC determinations. Given the current and evolving medical practices for management of seriously ill patients, further evaluations of the clinically important data about these yeasts are needed. PMID:8665465

Hazen, K C

1995-01-01

192

Development and characterization of 14 microsatellite loci in the Neotropical fish Geophagus brasiliensis (Perciformes, Cichlidae).  

PubMed

Fourteen polymorphic microsatellite loci were isolated and characterized for the Neotropical cichlid Geophagus brasiliensis and tested on 30 individuals belonging to a single population. Among the 14 loci described, four showed potential presence of null alleles, inferred from the excess of homozygous genotypes, and three of these loci showed significant deviations from Hardy-Weinberg equilibrium. Fifty-nine different alleles were detected (ranging from two to eight alleles per locus), with estimates of observed and expected heterozygosity ranging from 0·167 to 0·700 and from 0·269 to 0·825. Cross-amplification of primers was successful in five other cichlid species. PMID:24131284

Ferreira, D G; Galindo, B A; Alves, A N; Almeida, F S; Ruas, C F; Sofia, S H

2013-11-01

193

Modelling the Yeast Interactome  

PubMed Central

The topology behind biological interaction networks has been studied for over a decade. Yet, there is no definite agreement on the theoretical models which best describe protein-protein interaction (PPI) networks. Such models are critical to quantifying the significance of any empirical observation regarding those networks. Here, we perform a comprehensive analysis of yeast PPI networks in order to gain insights into their topology and its dependency on interaction-screening technology. We find that: (1) interaction-detection technology has little effect on the topology of PPI networks; (2) topology of these interaction networks differs in organisms with different cellular complexity (human and yeast); (3) clear topological difference is present between PPI networks, their functional sub-modules, and their inter-functional “linkers”; (4) high confidence PPI networks have more “geometrical” topology compared to predicted, incomplete, or noisy PPI networks; and (5) inter-functional “linker” proteins serve as mediators in signal transduction, transport, regulation and organisational cellular processes. PMID:24589662

Janji?, Vuk; Sharan, Roded; Pržulj, Nataša

2014-01-01

194

Sequence and expression analyses of ethylene response factors highly expressed in latex cells from Hevea brasiliensis.  

PubMed

The AP2/ERF superfamily encodes transcription factors that play a key role in plant development and responses to abiotic and biotic stress. In Hevea brasiliensis, ERF genes have been identified by RNA sequencing. This study set out to validate the number of HbERF genes, and identify ERF genes involved in the regulation of latex cell metabolism. A comprehensive Hevea transcriptome was improved using additional RNA reads from reproductive tissues. Newly assembled contigs were annotated in the Gene Ontology database and were assigned to 3 main categories. The AP2/ERF superfamily is the third most represented compared with other transcription factor families. A comparison with genomic scaffolds led to an estimation of 114 AP2/ERF genes and 1 soloist in Hevea brasiliensis. Based on a phylogenetic analysis, functions were predicted for 26 HbERF genes. A relative transcript abundance analysis was performed by real-time RT-PCR in various tissues. Transcripts of ERFs from group I and VIII were very abundant in all tissues while those of group VII were highly accumulated in latex cells. Seven of the thirty-five ERF expression marker genes were highly expressed in latex. Subcellular localization and transactivation analyses suggested that HbERF-VII candidate genes encoded functional transcription factors. PMID:24971876

Piyatrakul, Piyanuch; Yang, Meng; Putranto, Riza-Arief; Pirrello, Julien; Dessailly, Florence; Hu, Songnian; Summo, Marilyne; Theeravatanasuk, Kannikar; Leclercq, Julie; Kuswanhadi; Montoro, Pascal

2014-01-01

195

Pituitary gland morphogenesis and ontogeny of adenohypophyseal cells of Salminus brasiliensis (Teleostei, Characiformes).  

PubMed

In this study, we describe for the first time the details of the pituitary gland morphogenesis and the ontogeny of adenohypophyseal cells of a South American Characiform species with great importance for Brazilian Aquaculture, Salminus brasiliensis (Characiformes, Characidae), from hatching to 25 days after hatching (dah), by histochemical and immunocytochemical methods. The pituitary placode was first detected at hatching (0 dah), and the pituitary anlage became more defined at 0.5 dah. The neurohypophysis (NH) development started at 3 dah, and the early formation of its stalk at 12.5 dah. An increase in adenohypophyseal and NH tissues was also observed, and in juveniles at 25 dah, the pituitary displayed similar morphology to that found in adults of this species, displaying the main features of the teleost pituitary. PRL cells were detected at 0.5 dah, together with ACTH and ?-MSH cells, followed by GH and SL cells at 1.5 dah. ?-FSH cells were detected at 25 dah, while ?-LH cells at 5 dah. The pituitary development in this species comprises a dynamic process similar to other teleosts. Our findings in S. brasiliensis corroborate the heterogeneity in the ontogeny of adenohypophyseal cells in teleosts and suggest a role for adenohypophyseal hormones in the early development of this species. PMID:24310491

de Jesus, Lázaro Wender Oliveira; Chehade, Chayrra; Costa, Fabiano Gonçalves; Borella, Maria Inês

2014-06-01

196

Complement-dependent killing of Nippostrongylus brasiliensis infective larvae by rat alveolar macrophages.  

PubMed Central

Histopathological studies have provided circumstantial evidence that helminth parasite destruction occurs in the lung; however controlled in vitro studies on the helminthocidal activity of lung cells have not been reported. This study presents evidence that Nippostrongylus brasiliensis infection in the rat induces alterations in broncho-alveolar lavage (BAL) cell numbers, differential counts, and in vitro helminthocidal activity. Normal, uninfected rats yielded 3.3 +/- 0.6 X 10(6) BAL cells/rat, consisting predominantly of alveolar macrophages (greater than 90%). However on days 2-8 post-infection there was a 1.5-2.4-fold increase in BAL cell numbers with a significant neutrophilia on day 2 and a significant increase in the absolute number of all cell types on day 8. On day 32 post-infection, BAL cell numbers had returned to control levels. Normal BAL cells neither adhered to nor killed N. brasiliensis infective larvae (L3) in the presence of rat complement. By contrast BAL cells recovered from infected rats on days, 2, 8 or 32 post-infection (D2, D8 and D32 BAL cells, respectively) adhered under similar conditions. However, only D8 and D32 BAL cells killed L3. This complement-dependent killing correlated with significantly increased numbers of C3 receptor bearing alveolar macrophages in D8 and D32 BAL cells. Complement-dependent alveolar macrophage helminthocidal activity may therefore play an important role in lung resistance against resident or migrating helminths. PMID:6362933

Egwang, T G; Gauldie, J; Befus, D

1984-01-01

197

Interaction Between Yeasts and Zinc  

NASA Astrophysics Data System (ADS)

Zinc is an essential trace element in biological systems. For example, it acts as a cellular membrane stabiliser, plays a critical role in gene expression and genome modification and activates nearly 300 enzymes, including alcohol dehydrogenase. The present chapter will be focused on the influence of zinc on cell physiology of industrial yeast strains of Saccharomyces cerevisiae, with special regard to the uptake and subsequent utilisation of this metal. Zinc uptake by yeast is metabolism-dependent, with most of the available zinc translocated very quickly into the vacuole. At cell division, zinc is distributed from mother to daughter cells and this effectively lowers the individual cellular zinc concentration, which may become zinc depleted at the onset of the fermentation. Zinc influences yeast fermentative performance and examples will be provided relating to brewing and wine fermentations. Industrial yeasts are subjected to several stresses that may impair fermentation performance. Such stresses may also impact on yeast cell zinc homeostasis. This chapter will discuss the practical implications for the correct management of zinc bioavailability for yeast-based biotechnologies aimed at improving yeast growth, viability, fermentation performance and resistance to environmental stresses

Nicola, Raffaele De; Walker, Graeme

198

Lager Yeast Comes of Age  

PubMed Central

Alcoholic fermentations have accompanied human civilizations throughout our history. Lager yeasts have a several-century-long tradition of providing fresh beer with clean taste. The yeast strains used for lager beer fermentation have long been recognized as hybrids between two Saccharomyces species. We summarize the initial findings on this hybrid nature, the genomics/transcriptomics of lager yeasts, and established targets of strain improvements. Next-generation sequencing has provided fast access to yeast genomes. Its use in population genomics has uncovered many more hybridization events within Saccharomyces species, so that lager yeast hybrids are no longer the exception from the rule. These findings have led us to propose network evolution within Saccharomyces species. This “web of life” recognizes the ability of closely related species to exchange DNA and thus drain from a combined gene pool rather than be limited to a gene pool restricted by speciation. Within the domesticated lager yeasts, two groups, the Saaz and Frohberg groups, can be distinguished based on fermentation characteristics. Recent evidence suggests that these groups share an evolutionary history. We thus propose to refer to the Saaz group as Saccharomyces carlsbergensis and to the Frohberg group as Saccharomyces pastorianus based on their distinct genomes. New insight into the hybrid nature of lager yeast will provide novel directions for future strain improvement. PMID:25084862

2014-01-01

199

Lager yeast comes of age.  

PubMed

Alcoholic fermentations have accompanied human civilizations throughout our history. Lager yeasts have a several-century-long tradition of providing fresh beer with clean taste. The yeast strains used for lager beer fermentation have long been recognized as hybrids between two Saccharomyces species. We summarize the initial findings on this hybrid nature, the genomics/transcriptomics of lager yeasts, and established targets of strain improvements. Next-generation sequencing has provided fast access to yeast genomes. Its use in population genomics has uncovered many more hybridization events within Saccharomyces species, so that lager yeast hybrids are no longer the exception from the rule. These findings have led us to propose network evolution within Saccharomyces species. This "web of life" recognizes the ability of closely related species to exchange DNA and thus drain from a combined gene pool rather than be limited to a gene pool restricted by speciation. Within the domesticated lager yeasts, two groups, the Saaz and Frohberg groups, can be distinguished based on fermentation characteristics. Recent evidence suggests that these groups share an evolutionary history. We thus propose to refer to the Saaz group as Saccharomyces carlsbergensis and to the Frohberg group as Saccharomyces pastorianus based on their distinct genomes. New insight into the hybrid nature of lager yeast will provide novel directions for future strain improvement. PMID:25084862

Wendland, Jürgen

2014-10-01

200

Yeasts: From genetics to biotechnology  

SciTech Connect

Yeasts have been known and used in food and alcoholic fermentations ever since the Neolithic Age. In more recent times, on the basis of their peculiar features and history, yeasts have become very important experimental models in both microbiological and genetic research, as well as the main characters in many fermentative production processes. In the last 40 years, advances in molecular biology and genetic engineering have made possible not only the genetic selection of organisms, but also the genetic modification of some of them, especially the simplest of them, such as bacteria and yeasts. These discoveries have led to the availability of new yeast strains fit to fulfill requests of industrial production and fermentation. Moreover, genetically modified and transformed yeasts have been constructed that are able to produce large amounts of biologically active proteins and enzymes. Thus, recombinant yeasts make it easier to produce drugs, biologically active products, diagnostics, and vaccines, by inexpensive and relatively simple techniques. Yeasts are going to become more and more important in the {open_quotes}biotechnological revolution{close_quotes} by virtue of both their features and their very long and safe use in human nutrition and industry. 175 refs., 4 figs., 6 tabs.

Russo, S.; Poli, G. [Univ. of Milan (Italy); Siman-Tov, R.B. [Univ. of Jerusalem, Rehovot (Israel)

1995-12-31

201

Antioxidative and immunomodulating activities of polysaccharide extracts of the medicinal mushrooms Agaricus bisporus, Agaricus brasiliensis, Ganoderma lucidum and Phellinus linteus  

Microsoft Academic Search

Partially purified polysaccharides were obtained from four medicinal mushroom species, Agaricus bisporus, Agaricus brasiliensis, Phellinus linteus and Ganoderma lucidum by hot water extraction, followed by ethanol precipitation. The four samples contained varying amounts of both ?- and ?-glucans as determined by FT-IR and by quantitative estimation after prior partial hydrolysis (Megazyme ?-glucan assay kit). EC50 values of the DPPH scavenging

Maja Kozarski; Anita Klaus; Miomir Niksic; Dragica Jakovljevic; Johannes P. F. G. Helsper

2011-01-01

202

Isistius brasiliensis, A SQUALOID SHARK, THE PROBABLE CAU E OF CRATER W OUNDS ON FISHES AND CETACEANS  

E-print Network

Isistius brasiliensis, A SQUALOID SHARK, THE PROBABLE CAU E OF CRATER W OUNDS ON FISHES k, f.~islills b rr/.~iliellsiR (Quo)' and Gaimard) , are the causes of crater wounds, crescentic evidence that many crater wounds, crescentic wound, and the resulting scars on pelagic fishes (Figure 1

203

Comparative study on the technological properties of latex and natural rubber from Hancornia speciosa Gomes and Hevea brasiliensis  

Technology Transfer Automated Retrieval System (TEKTRAN)

This work reports a systematic comparative study of the properties of natural lattices and rubbers extracted from Hancornia speciosa Gomes and Hevea brasiliensis [(Willd. ex Adr. de Juss.) Muell.-Arg.] (clone RRIM 600) trees from 11 collections in Brazil throughout 2004. Natural rubber latex particl...

204

Habitat use by Myotis yumanensis and Tadarida brasiliensis mexicana in South San Francisco Bay wetlands: An Acoustic Study  

Microsoft Academic Search

Research on bat habitat use within coastal estuaries is limited. The purposes of my study were to determine whether Yuma myotis (Myotis yumanensis) and Mexican free-tailed bats (Tadarida brasiliensis mexicana) differentiate between open water and marsh within saline and brackish habitats and to examine whether climatic factors are correlated with general activity and tidal height with foraging of the two

Theresa Brickley

2012-01-01

205

EVIDENCE FOR PRENATAL TRANSFER OF RABIES VIRUS IN THE MEXICAN FREE-TAILED BAT (TADARIDA BRASILIENSIS MEXICANA)  

Microsoft Academic Search

Fetuses were collected from four Mexican free-tailed bats (Tadarida brasiliensis niexicana) and a fetal bat cell (FBC) line was established and tested for its ability to support the replication of the ERA vaccine strain of rabies virus. Cytopathic effects were detected in ERA virus-inoculated as well as uninoculated FBC's. Immunoflorescent antibody testing of uninoculated FBC's provided no evidence for the

Richard S. Steece; Charles H. Calisher

206

Marine yeast isolation and industrial application  

PubMed Central

Over the last century, terrestrial yeasts have been widely used in various industries, such as baking, brewing, wine, bioethanol and pharmaceutical protein production. However, only little attention has been given to marine yeasts. Recent research showed that marine yeasts have several unique and promising features over the terrestrial yeasts, for example higher osmosis tolerance, higher special chemical productivity and production of industrial enzymes. These indicate that marine yeasts have great potential to be applied in various industries. This review gathers the most recent techniques used for marine yeast isolation as well as the latest applications of marine yeast in bioethanol, pharmaceutical and enzyme production fields. PMID:24738708

Zaky, Abdelrahman Saleh; Tucker, Gregory A; Daw, Zakaria Yehia; Du, Chenyu

2014-01-01

207

Domestic, peridomestic and wild hosts in the transmission of Trypanosoma cruzi in the Caatinga area colonised by Triatoma brasiliensis  

PubMed Central

The role played by different mammal species in the maintenance of Trypanosoma cruzi is not constant and varies in time and place. This study aimed to characterise the importance of domestic, wild and peridomestic hosts in the transmission of T. cruzi in Tauá, state of Ceará, Caatinga area, Brazil, with an emphasis on those environments colonised by Triatoma brasiliensis. Direct parasitological examinations were performed on insects and mammals, serologic tests were performed on household and outdoor mammals and multiplex polymerase chain reaction was used on wild mammals. Cytochrome b was used as a food source for wild insects. The serum prevalence in dogs was 38% (20/53), while in pigs it was 6% (2/34). The percentages of the most abundantly infected wild animals were as follows: Thrichomys laurentius 74% (83/112) and Kerodon rupestris 10% (11/112). Of the 749 triatomines collected in the household research, 49.3% (369/749) were positive for T. brasiliensis, while 6.8% were infected with T. cruzi (25/369). In captured animals, T. brasiliensis shares a natural environment with T. laurentius, K. rupestris, Didelphis albiventris, Monodelphis domestica, Galea spixii, Wiedomys pyrrhorhinos, Conepatus semistriatus and Mus musculus. In animals identified via their food source, T. brasiliensis shares a natural environment with G. spixii, K. rupestris, Capra hircus, Gallus gallus, Tropidurus oreadicus and Tupinambis merianae. The high prevalence of T. cruzi in household and peridomiciliar animals reinforces the narrow relationship between the enzootic cycle and humans in environments with T. brasiliensis and characterises it as ubiquitous. PMID:25410992

Bezerra, Claudia Mendonça; Cavalcanti, Luciano Pamplona de Góes; de Souza, Rita de Cássia Moreira; Barbosa, Silvia Ermelinda; Xavier, Samanta Cristina das Chagas; Jansen, Ana Maria; Ramalho, Relrison Dias; Diotaiut, Liléia

2014-01-01

208

Transcriptome Sequencing of Hevea brasiliensis for Development of Microsatellite Markers and Construction of a Genetic Linkage Map  

PubMed Central

To obtain more information on the Hevea brasiliensis genome, we sequenced the transcriptome from the vegetative shoot apex yielding 2 311 497 reads. Clustering and assembly of the reads produced a total of 113 313 unique sequences, comprising 28 387 isotigs and 84 926 singletons. Also, 17 819 expressed sequence tag (EST)-simple sequence repeats (SSRs) were identified from the data set. To demonstrate the use of this EST resource for marker development, primers were designed for 430 of the EST-SSRs. Three hundred and twenty-three primer pairs were amplifiable in H. brasiliensis clones. Polymorphic information content values of selected 47 SSRs among 20 H. brasiliensis clones ranged from 0.13 to 0.71, with an average of 0.51. A dendrogram of genetic similarities between the 20 H. brasiliensis clones using these 47 EST-SSRs suggested two distinct groups that correlated well with clone pedigree. These novel EST-SSRs together with the published SSRs were used for the construction of an integrated parental linkage map of H. brasiliensis based on 81 lines of an F1 mapping population. The map consisted of 97 loci, consisting of 37 novel EST-SSRs and 60 published SSRs, distributed on 23 linkage groups and covered 842.9 cM with a mean interval of 11.9 cM and ?4 loci per linkage group. Although the numbers of linkage groups exceed the haploid number (18), but with several common markers between homologous linkage groups with the previous map indicated that the F1 map in this study is appropriate for further study in marker-assisted selection. PMID:22086998

Triwitayakorn, Kanokporn; Chatkulkawin, Pornsupa; Kanjanawattanawong, Supanath; Sraphet, Supajit; Yoocha, Thippawan; Sangsrakru, Duangjai; Chanprasert, Juntima; Ngamphiw, Chumpol; Jomchai, Nukoon; Therawattanasuk, Kanikar; Tangphatsornruang, Sithichoke

2011-01-01

209

Molecular Genetic Analysis in Yeast  

NSDL National Science Digital Library

The four exercises presented here use basic and advanced procedures of recombinant DNA technology to perform molecular genetic analysis in the yeast Saccharomyces cerevisiae. Their fulluse is intended for a senior-level molecular genetics (or similar) course; however, Experiments 1, 2, and 4 are appropriate for lower-level courses. It is expected that the instructor will have some familiarity with the concepts and terminology of recombinant DNA technology and with yeast genetics.

Daniel D. Burke (Seton Hall University; )

1989-06-06

210

Biotechnological Applications of Dimorphic Yeasts  

NASA Astrophysics Data System (ADS)

The dimorphic yeasts have the equilibrium between spherical growth (budding) and polarized (hyphal or pseudohyphal tip elongation) which can be triggered by change in the environmental conditions. The reversible growth phenomenon has made dimorphic yeasts as an useful model to understand fungal evolution and fungal differentiation, in general. In nature dimorphism is clearly evident in plant and animal fungal pathogens, which survive and most importantly proliferate in the respective hosts. However, number of organisms with no known pathogenic behaviour also show such a transition, which can be exploited for the technological applications due to their different biochemical make up under different morphologies. For instance, chitin and chitosan production using dimorphic Saccharomyces, Mucor, Rhizopus and Benjaminiella, oil degradation and biotransformation with yeast-form of Yarrowia species, bioremediation of organic pollutants, exopolysac-charide production by yeast-phase of Aureobasidium pullulans, to name a few. Myrothecium verrucaria can be used for seed dressing in its yeast form and it produces a mycolytic enzyme complex in its hyphal-form for the biocontrol of fungal pathogens, while Beauveria bassiana and other entomopathogens kill the insect pest by producing yeast- like cells in the insect body. The form-specific expression of protease, chitinase, lipase, ornithine decarboxylase, glutamate dehydrogenases, etc. make Benjaminiella poitrasii, Basidiobolus sp., and Mucor rouxii strains important in bioremediation, nanobiotechnology, fungal evolution and other areas.

Doiphode, N.; Joshi, C.; Ghormade, V.; Deshpande, M. V.

211

Study of amyloids using yeast  

PubMed Central

Summary Saccharomyces cerevisiae has been a useful model organism in such fields as the cell cycle, regulation of transcription, protein trafficking and cell biology, primarily because of its ease of genetic manipulation. This is no less so in the area of amyloid studies. The endogenous yeast amyloids described to date include prions, infectious proteins (Table 1), and some cell wall proteins (1). and amyloids of humans and a fungal prion have also been studied using the yeast system. Accordingly, the emphasis of this chapter will be on genetic, biochemical, cell biological and physical methods particularly useful in the study of yeast prions and other amyloids studied in yeast. We limit our description of these methods to those aspects which have been most useful in studying yeast prions, citing more detailed expositions in the literature. Volumes on yeast genetics methods (2–4), and on amyloids and prions (5, 6) are useful, and Masison has edited a volume of Methods on “Identification, analysis and characterization of fungal prions” which covers some of this territory (7). We also outline some useful physical methods, pointing the reader to more extensive and authoratative descriptions. PMID:22528100

Wickner, Reed B.; Kryndushkin, Dmitry; Shewmaker, Frank; McGlinchey, Ryan; Edskes, Herman K.

2012-01-01

212

Ecological niche modeling and differentiation of populations of *Triatoma brasiliensis* Neiva, 1911, the most important Chagas disease vector in northeastern Brazil (Hemiptera, Reduviidae, Triatominae)  

E-print Network

characterize ecologic differentiation of Triatoma brasiliensis populations, the most important Chagas’ disease vector in northeastern Brazil. The species’ ecologic niche was modeled based on data from the Fundação Nacionalde Saúde of Brazil(1997...

Costa, Jane; Peterson, A. Townsend; Beard, C. Ben

2002-11-01

213

Cultivated strains of Agaricus bisporus and A. brasiliensis: chemical characterization and evaluation of antioxidant and antimicrobial properties for the final healthy product--natural preservatives in yoghurt.  

PubMed

Agaricus bisporus (J. E. Lange) Emil J. Imbach and Agaricus brasiliensis Wasser, M. Didukh, Amazonas & Stamets are edible mushrooms. We chemically characterized these mushrooms for nutritional value, hydrophilic and lipophilic compounds. The antioxidant and antimicrobial activities of methanolic and ethanolic extracts were assessed. Hepatotoxicity was also evaluated. The ethanolic extract of both species was tested for inhibition of Listeria monocytogenes growth in yoghurt. Both species proved to be a good source of bioactive compounds. A. brasiliensis was richer in polyunsaturated fatty acids and revealed the highest concentration of phenolic acids, and tocopherols. A. bisporus showed the highest monounsaturated fatty acids and ergosterol contents. A. brasiliensis revealed the highest antioxidant potential, and its ethanolic extract displayed the highest antibacterial potential; the methanolic extract of A. bisporus revealed the highest antifungal activity. A. brasiliensis possessed better preserving properties in yoghurt. PMID:24881564

Stojkovi?, Dejan; Reis, Filipa S; Glamo?lija, Jasmina; ?iri?, Ana; Barros, Lillian; Van Griensven, Leo J L D; Ferreira, Isabel C F R; Sokovi?, Marina

2014-07-25

214

Metabolic regulation of yeast  

NASA Astrophysics Data System (ADS)

Metabolic regulation which is based on endogeneous and exogeneous process variables which may act constantly or time dependently on the living cell is discussed. The observed phenomena of the regulation are the result of physical, chemical, and biological parameters. These parameters are identified. Ethanol is accumulated as an intermediate product and the synthesis of biomass is reduced. This regulatory effect of glucose is used for the aerobic production of ethanol. Very high production rates are thereby obtained. Understanding of the regulation mechanism of the glucose effect has improved. In addition to catabolite repression, several other mechanisms of enzyme regulation have been described, that are mostly governed by exogeneous factors. Glucose also affects the control of respiration in a third class of yeasts which are unable to make use of ethanol as a substrate for growth. This is due to the lack of any anaplerotic activity. As a consequence, diauxic growth behavior is reduced to a one-stage growth with a drastically reduced cell yield. The pulse chemostat technique, a systematic approach for medium design is developed and medium supplements that are essential for metabolic control are identified.

Fiechter, A.

1982-12-01

215

Riboneogenesis in yeast  

PubMed Central

Summary Gluconeogenesis converts three carbon units into glucose. Here we identify an analogous pathway in Saccharomyces cerevisiae for converting three carbon units into ribose, a component of nucleic acids and nucleotides. This riboneogenic pathway involves the enzyme sedoheptulose-1,7-bisphosphatase (SHB17), whose activity was identified based on accumulation of sedoheptulose-1,7-bisphosphate in the corresponding knockout strain. We determined the crystal structure of Shb17 in complex with sedoheptulose-1,7-bisphosphate, and found that the sugar is bound in the closed furan form in the active site. Like fructose-1,6-bisphosphate, sedoheptulose-1,7-bisphosphate is produced by aldolase, in this case from erythrose 4-phosphate and dihydroxyacetone phosphate. Hydrolysis of sedoheptulose-1,7-bisphosphate by SHB17 provides an energetically favorable input to the non-oxidative pentose phosphate pathway to drive ribose production. Flux through SHB17 is enhanced under conditions when ribose demand is high relative to demand for NADPH, including during ribosome biogenesis in metabolically synchronized yeast cells. Thus, riboneogenesis provides a thermodynamically-driven route of ribose production uncoupled from formation of NADPH. PMID:21663798

Clasquin, Michelle F.; Melamud, Eugene; Singer, Alexander; Gooding, Jessica R.; Xu, Xiaohui; Dong, Aiping; Cui, Hong; Campagna, Shawn R.; Savchenko, Alexei; Yakunin, Alexander F.; Rabinowitz, Joshua D.; Caudy, Amy A.

2011-01-01

216

Tourism values for Mexican free-tailed bat (Tadarida brasiliensis mexicana) viewing  

USGS Publications Warehouse

Migratory species provide diverse ecosystem services to people, but these values have seldom been estimated rangewide for a single species. In this article, we summarize visitation and consumer surplus for recreational visitors to viewing sites for the Mexican free-tailed bat (Tadarida brasiliensis mexicana) throughout the Southwestern United States. Public bat viewing opportunities are available at 17 of 25 major roosts across six states; on an annual basis, we estimate that over 242,000 visitors view bats, gaining over $6.5 million in consumer surplus. A better understanding of spatial mismatches between the areas where bats provide value to people and areas most critical for maintaining migratory populations can better inform conservation planning, including economic incentive systems for conservation.

Bagstad, Kenneth J.; Widerholdt, Ruscena

2013-01-01

217

Dracunculus brasiliensis sp. n. (Nematoda: Dracunculidae) from the anaconda, Eunectes murinus (Ophidia: Boidae).  

PubMed

Dracunculus brasiliensis sp. n. (Dracunculidae), is described based on a single female specimen found in the body cavity of the anaconda, Eunectes murinus (L.) (Ophidia: Boidae), from the Mexiana Island, Amazon River delta, Brazil and one female previously recorded from the subcutaneous tissue of this host species imported from South America into Europe (ZOO in the Czech Republic). The new species is characterised mainly by markedly large, anteriorly protruding dorsal and ventral double papillae of the internal circle and small lateral papillae of the same circle, a widely rounded caudal end, the excretory pore situated just posterior to the nerve ring, a distinctly transversely striated cuticle and by the length (396-429 mum) of larvae from uterus. This is the first species of Dracunculus described from reptiles in South America. PMID:18975002

Moravec, F; Santos, C P

2009-02-01

218

Anthocyanins from Eugenia brasiliensis edible fruits as potential therapeutics for COPD treatment  

PubMed Central

Nine anthocyanins (1–9) from the edible fruits of Eugenia brasiliensis were identified by HPLC-PDA and LC-MS, and seven of these are described for the first time in this Brazilian fruit. Two of the major anthocyanins, delphinidin (8) and cyanidin (9), were studied for their inhibitory activity against chemokine interleukin-8 (IL-8) production before and after cigarette smoke extract (CSE) treatment of cells. In non-treated cells the amount of IL-8 was unchanged following treatment with cyanidin and delphinidin in concentrations 0.1–10 M. Both delphinidin (8) and cyanidin (9) decreased the production of IL-8 in treated cells, at 1 M and 10 M, respectively. Delphinidin (8) demonstrated IL-8 inhibition in the CSE treated cells in a dose-dependent manner. PMID:25005941

Flores, Gema; Dastmalchi, Keyvan; Paulino, Sturlainny; Whalen, Kathleen; Dabo, Abdoulaye J.; Reynertson, Kurt A.; Foronjy, Robert F.; D Armiento, Jeanine M.; Kennelly, Edward J.

2012-01-01

219

Mercury levels in tissues of Giant otters (Pteronura brasiliensis) from the Rio Negro, Pantanal, Brazil.  

PubMed

This research reports the first data on mercury levels found in Giant otters (Pteronura brasiliensis) from South America. Mercury concentrations were analyzed from different organs/tissues of two animals found dead floating on the water of the Rio Negro in the Pantanal, Brazil. The mean mercury concentration ranged from 2.94 to 3.68 microg/g in hair, from 1.52 to 4.3 microg/g in liver, and from 1.11 to 4.59 microg/g in kidney and was 0.17 microg/g in muscle samples. In comparison with other research, there is no evidence of contamination in these animals and mercury concentrations in tissues appeared to be at levels below those associated with toxicity. PMID:15910792

Dias Fonseca, Fabrizio Rafael; Malm, Olaf; Francine Waldemarin, Helen

2005-07-01

220

The primary structure of hevamine, an enzyme with lysozyme/chitinase activity from Hevea brasiliensis latex.  

PubMed

The primary structure of hevamine, an enzyme with lysozyme/chitinase activity from Hevea brasiliensis latex, has been determined predominantly with conventional non-automatic methods. The positions of three disulfide bridges have been determined. The sequence has about 60% identity with that of a chitinase from cucumber and 95% with the N-terminal sequence of the lysozyme/chitinase of Parthenocissus quinquefolia. The half-cystine residues in hevein and cucumber chitinase are located at identical positions. Hevamine is a basic protein from the lutoids (vacuoles) of rubber latex and may have a role in plugging the latex vessels and cessation of latex flow. The differences in cellular location, charge properties and sequence between hevamine and cucumber chitinase are similar to those between class I and class II chitinases from tobacco and other plant species. PMID:1879417

Jekel, P A; Hartmann, B H; Beintema, J J

1991-08-15

221

PCR for Diagnosis of Paracoccidioidomycosis  

Microsoft Academic Search

A PCR assay based on oligonucleotide primers derived from the sequence of the gene coding for the 43,000-Da (gp43) antigen was developed to detect Paracoccidioides brasiliensis DNA in sputa. In the standard- ized conditions, it could detect 10 cells\\/ml of sputum, providing sufficient accuracy to be useful for diagnosis of paracoccidioidomycosis. Paracoccidioides brasiliensis, a thermodimorphic fungus, is the causative agent

GLAUCE M. GOMES; PATRICIA S. CISALPINO; CARLOS P. TABORDA; ZOILO P. DE CAMARGO

2000-01-01

222

Sucrose importation into laticifers of Hevea brasiliensis, in relation to ethylene stimulation of latex production  

PubMed Central

Background and Aims The major economic product of Hevea brasiliensis is a rubber-containing cytoplasm (latex), which flows out of laticifers (latex cells) when the bark is tapped. The latex yield is stimulated by ethylene. Sucrose, the unique precursor of rubber synthesis, must cross the plasma membrane through specific sucrose transporters before being metabolized in the laticifers. The relative importance of sucrose transporters in determining latex yield is unknown. Here, the effects of ethylene (by application of Ethrel®) on sucrose transporter gene expression in the inner bark tissues and latex cells of H. brasiliensis are described. Methods Experiments, including cloning sucrose transporters, real time RT-PCR and in situ hybridization, were carried out on virgin (untapped) trees, treated or untreated with the latex yield stimulant Ethrel. Key Results Seven putative full-length cDNAs of sucrose transporters were cloned from a latex-specific cDNA library. These transporters belong to all SUT (sucrose transporter) groups and differ by their basal gene expression in latex and inner soft bark, with a predominance of HbSUT1A and HbSUT1B. Of these sucrose transporters, only HbSUT1A and HbSUT2A were distinctly increased by ethylene. Moreover, this increase was shown to be specific to laticifers and to ethylene application. Conclusion The data and all previous information on sucrose transport show that HbSUT1A and HbSUT2A are related to the increase in sucrose import into laticifers, required for the stimulation of latex yield by ethylene in virgin trees. PMID:19567416

Dusotoit-Coucaud, Anaïs; Brunel, Nicole; Kongsawadworakul, Panida; Viboonjun, Unchera; Lacointe, André; Julien, Jean-Louis; Chrestin, Hervé; Sakr, Soulaïman

2009-01-01

223

Population growth of Mexican free-tailed bats (Tadarida brasiliensis mexicana) predates human agricultural activity  

PubMed Central

Background Human activities, such as agriculture, hunting, and habitat modification, exert a significant effect on native species. Although many species have suffered population declines, increased population fragmentation, or even extinction in connection with these human impacts, others seem to have benefitted from human modification of their habitat. Here we examine whether population growth in an insectivorous bat (Tadarida brasiliensis mexicana) can be attributed to the widespread expansion of agriculture in North America following European settlement. Colonies of T. b. mexicana are extremely large (~106 individuals) and, in the modern era, major agricultural insect pests form an important component of their food resource. It is thus hypothesized that the growth of these insectivorous bat populations was coupled to the expansion of agricultural land use in North America over the last few centuries. Results We sequenced one haploid and one autosomal locus to determine the rate and time of onset of population growth in T. b. mexicana. Using an approximate Maximum Likelihood method, we have determined that T. b. mexicana populations began to grow ~220 kya from a relatively small ancestral effective population size before reaching the large effective population size observed today. Conclusions Our analyses reject the hypothesis that T. b. mexicana populations grew in connection with the expansion of human agriculture in North America, and instead suggest that this growth commenced long before the arrival of humans. As T. brasiliensis is a subtropical species, we hypothesize that the observed signals of population growth may instead reflect range expansions of ancestral bat populations from southern glacial refugia during the tail end of the Pleistocene. PMID:21457563

2011-01-01

224

Yeast Genetics and Biotechnological Applications  

NASA Astrophysics Data System (ADS)

Yeast can be recognized as one of the very important groups of microorganisms on account of its extensive use in the fermentation industry and as a basic eukaryotic model cellular system. The yeast Saccharomyces cerevisiae has been extensively used to elucidate the genetics and regulation of several key functions in the cell such as cell mating, electron transport chain, protein trafficking, cell cycle events and others. Even before the genome sequence of the yeast was out, the structural organization and function of several of its genes was known. With the availability of the origin of replication from the 2 ?m plasmid and the development of transformation system, it became the host of choice for expression of a number of important proteins. A large number of episomal and integrative shuttle vectors are available for expression of mammalian proteins. The latest developments in genomics and micro-array technology have allowed investigations of individual gene function by site-specific deletion method. The application of metabolic profiling has also assisted in understanding the cellular network operating in this yeast. This chapter is aimed at reviewing the use of this system as an experimental tool for conducting classical genetics. Various vector systems available, foreign genes expressed and the limitations as a host will be discussed. Finally, the use of various yeast enzymes in biotechnology sector will be reviewed.

Mishra, Saroj; Baranwal, Richa

225

Nuclear Transport of Yeast Proteasomes  

PubMed Central

Proteasomes are conserved protease complexes enriched in the nuclei of dividing yeast cells, a major site for protein degradation. If yeast cells do not proliferate and transit to quiescence, metabolic changes result in the dissociation of proteasomes into proteolytic core and regulatory complexes and their sequestration into motile cytosolic proteasome storage granuli. These granuli rapidly clear with the resumption of growth, releasing the stored proteasomes, which relocalize back to the nucleus to promote cell cycle progression. Here, I report on three models of how proteasomes are transported from the cytoplasm into the nucleus of yeast cells. The first model applies for dividing yeast and is based on the canonical pathway using classical nuclear localization sequences of proteasomal subcomplexes and the classical import receptor importin/karyopherin ??. The second model applies for quiescent yeast cells, which resume growth and use Blm10, a HEAT-like repeat protein structurally related to karyopherin ?, for nuclear import of proteasome core particles. In the third model, the fully-assembled proteasome is imported into the nucleus. Our still marginal knowledge about proteasome dynamics will inspire the discussion on how protein degradation by proteasomes may be regulated in different cellular compartments of dividing and quiescent eukaryotic cells. PMID:25333764

Enenkel, Cordula

2014-01-01

226

ORIGINAL PAPER Evolutionarily engineered ethanologenic yeast detoxifies  

E-print Network

ORIGINAL PAPER Evolutionarily engineered ethanologenic yeast detoxifies lignocellulosic biomass with subsequent fermentation of ethanol, posing significant challenges for a sustainable cellulosic ethanol conversion industry. Numerous yeast genes were found to be associated with the inhibitor tolerance. However

Song, Joe

227

PHYLOGENETICS OF SACCHAROMYCETALES, THE ASCOMYCETE YEASTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ascomycete yeasts (Phylum Ascomycota: Subphylum Saccharomycotina: Class Saccharomycetes: Order Saccharomycetales) comprise a monophyletic lineage with a single order of about 1000 known species. These yeasts live as saprobes, often in association with plants, animals, and their interfaces. A few s...

228

Bacteria, Yeast and Chemicals on Human Skin  

MedlinePLUS Videos and Cool Tools

... the lower right-hand corner of the player. Bacteria, Yeast and Chemicals on Human Skin HealthDay April ... the distribution and quantity of metabolites, peptides, lipids, bacteria, yeast, proteins, chemicals and more. As expected, many ...

229

Cdc42 Oscillations in Yeasts  

NSDL National Science Digital Library

A fundamental problem in cell biology is how cells define one or several discrete sites of polarity. Through mechanisms involving positive and negative feedback, the small Rho-family guanosine triphosphatase Cdc42 breaks symmetry in round budding yeast cells to define a single site of polarized cell growth. However, it is not clear how cells can define multiple sites of polarization concurrently. We discuss a study in which rod-shaped fission yeast cells, which naturally polarize growth at their two cell ends, exhibited oscillations of Cdc42 activity between these sites. We compare these findings with similar oscillatory behavior of Cdc42 detected in budding yeast cells and discuss the possible mechanism and functional outputs of these oscillations.

Felipe O. Bendezu (Switzerland; University of Lausanne REV)

2012-12-04

230

Hevea brasiliensis REF (Hev b 1) and SRPP (Hev b 3): An overview on rubber particle proteins.  

PubMed

This review article aims to gather all the knowledge on two important proteins associated with Hevea brasiliensis rubber particles: namely the rubber elongation factor (REF) and the small rubber particle protein (SRPP). It covers more then three decades of research on these two proteins and their homologues in plants, and particularly emphasizes on the different possible properties or functions of these various proteins found in plants. PMID:25019490

Berthelot, Karine; Lecomte, Sophie; Estevez, Yannick; Peruch, Frédéric

2014-11-01

231

Wound-Induced Accumulation of mRNA Containing a Hevein Sequence in Laticifers of Rubber Tree (Hevea brasiliensis)  

Microsoft Academic Search

Hevein is a chitin-binding protein that is present in laticifers of the rubber tree (Hevea brasiliensis). A cDNA clone (HEV1) encoding hevein was isolated by using the polymerase chain reaction with mixed oligonucleotides corresponding to two regions of hevein as primers and a Hevea latex cDNA library as a template. HEV1 is 1018 base pairs long and includes an open

Willem Broekaert; Hyung-Il Lee; Anil Kush; Nam-Hai Chua; Natasha Raikhel

1990-01-01

232

Hev b 8, the Hevea brasiliensis Latex Profilin, Is a Cross-Reactive Allergen of Latex, Plant Foods and Pollen  

Microsoft Academic Search

Background: Plant profilins are important pan-allergens. They are responsible for a significant percentage of pollen-related allergies. Limited information is available about their involvement in the latex-fruit syndrome and the cross-reactivities between latex and pollen. We aimed to clone and express the Hevea brasiliensis latex profilin to investigate its allergological significance and serological cross-reactivities to profilins from plant foods and pollens.

Erika Ganglberger; Christian Radauer; Stefan Wagner; Gabriel Ó Ríordáin; Donald H. Beezhold; Randolf Brehler; Bodo Niggemann; Otto Scheiner; Erika Jensen-Jarolim; Heimo Breiteneder

2001-01-01

233

The tiny difference between foraging and communication buzzes uttered by the Mexican free-tailed bat, Tadarida brasiliensis  

Microsoft Academic Search

Echolocating insectivorous bats consummate prey captures using a distinct vocal motor pattern commonly known as the terminal\\u000a or feeding buzz, which is widely considered a fixed motor pattern executed independently of auditory feedback influences.\\u000a The Mexican free-tailed bat, Tadarida brasiliensis, offers an opportunity to explore the role of sensory feedback in buzzing because they emit similar buzzes both in flight

Christine Schwartz; Jedidiah Tressler; Halli Keller; Marc Vanzant; Sarah Ezell; Michael Smotherman

2007-01-01

234

Natural rubber, Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg, germplasm collection in the Amazon Basin, Brazil: A retrospective  

Microsoft Academic Search

Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg., whose center of diversity is the Amazon basin, is the major source of commercial rubber\\u000a in the world. In the 1970s, the need for new Hevea germplasm arose from the realization that there was a gradual erosion of\\u000a the genetic variability of the rubber clones in many natural rubber plantations. This erosion

U. Onokpise Oghenekome

2004-01-01

235

Protective Immunity and Eosinophilia in IgE-Deficient SJA\\/9 Mice Infected with Nippostrongylus brasiliensis and Trichinella spiralis  

Microsoft Academic Search

To elucidate the roles of IgE antibody in host responses to helminth infection, selective IgE-deficient SJA\\/9 mice were infected with the nematode parasites Nippostrongylus brasiliensis, which elicits remarkable potentiated IgE production, and Trichinella spiralis, which induces strong anti-Trichinella IgE antibody production in normal mice. The kinetics of blood eosinophilia, worm burden after primary infection, and resistance to secondary infection in

Naohiro Watanabe; Ken Katakura; Akio Kobayashi; Ko Okumura; Zoltan Ovary

1988-01-01

236

Distributional potential of the Triatoma brasiliensis species complex at present and under scenarios of future climate conditions  

PubMed Central

Background The Triatoma brasiliensis complex is a monophyletic group, comprising three species, one of which includes two subspecific taxa, distributed across 12 Brazilian states, in the caatinga and cerrado biomes. Members of the complex are diverse in terms of epidemiological importance, morphology, biology, ecology, and genetics. Triatoma b. brasiliensis is the most disease-relevant member of the complex in terms of epidemiology, extensive distribution, broad feeding preferences, broad ecological distribution, and high rates of infection with Trypanosoma cruzi; consequently, it is considered the principal vector of Chagas disease in northeastern Brazil. Methods We used ecological niche models to estimate potential distributions of all members of the complex, and evaluated the potential for suitable adjacent areas to be colonized; we also present first evaluations of potential for climate change-mediated distributional shifts. Models were developed using the GARP and Maxent algorithms. Results Models for three members of the complex (T. b. brasiliensis, N?=?332; T. b. macromelasoma, N?=?35; and T. juazeirensis, N?=?78) had significant distributional predictivity; however, models for T. sherlocki and T. melanica, both with very small sample sizes (N?=?7), did not yield predictions that performed better than random. Model projections onto future-climate scenarios indicated little broad-scale potential for change in the potential distribution of the complex through 2050. Conclusions This study suggests that T. b. brasiliensis is the member of the complex with the greatest distributional potential to colonize new areas: overall; however, the distribution of the complex appears relatively stable. These analyses offer key information to guide proactive monitoring and remediation activities to reduce risk of Chagas disease transmission. PMID:24886587

2014-01-01

237

Identification of a Hevea brasiliensis Latex Manganese Superoxide Dismutase (Hev b 10) as a Cross-Reactive Allergen  

Microsoft Academic Search

Background: Cross-reactive allergens play an increasingly important role in latex allergy in complicating both the diagnosis and time course of allergic symptoms. Manganese superoxide dismutase (MnSOD), a ubiquitous protein of prokaryotic and eukaryotic organisms, was described as a cross-reactive allergen in Aspergillus fumigatus. Little information is available on the importance of this pan-allergen in Hevea brasiliensis latex. The aim of

Stefan Wagner; Slawomir Sowka; Christina Mayer; Reto Crameri; Margit Focke; Viswanath P. Kurup; Otto Scheiner; Heimo Breiteneder

2001-01-01

238

Development, characterization and cross-species\\/genera transferability of EST-SSR markers for rubber tree ( Hevea brasiliensis )  

Microsoft Academic Search

Expressed sequence tags derived simple sequence repeats (EST-SSRs), are different from traditional genomic SSR (gSSR) markers.\\u000a They are more likely to be embedded in the functional gene sequences, less costly and time effective, and may provide abundant\\u000a information. By analysis of 10,018 expressed sequence tags (ESTs) out of 10,829 for rubber tree (Hevea brasiliensis) available in public domain DNA databases,

S. P. Feng; W. G. Li; H. S. Huang; J. Y. Wang; Y. T. Wu

2009-01-01

239

Sorption of grape proanthocyanidins and wine polyphenols by yeasts, inactivated yeasts, and yeast cell walls.  

PubMed

Inactivated yeast fractions (IYFs) can be used in enology to improve the stability and mouthfeel of red wines. However, information concerning the mechanisms involved and the impact of the IYF characteristics is scarce. Adsorption isotherms were used to investigate interactions between grape proanthocyanidin fractions (PAs) or wine polyphenols (WP) and a commercial yeast strain (Y), the inactivated yeast (IY), the yeast submitted to autolyzis and inactivation (A-IY), and the cell walls obtained by mechanical disruption (CW). High affinity isotherms and high adsorption capacities were observed for grape PAs and whole cells (Y, IY, and A-IY). Affinity and adsorbed amount were lower with wine PAs, due to chemical changes occurring during winemaking. By contrast to whole cells, grape PAs and WP adsorption on CW remained very low. This raises the issue of the part played by cell walls in the interactions between yeast and proanthocyanidins and suggests the passage of the latter through the wall pores and their interaction with the plasma membrane. PMID:25575250

Mekoue Nguela, J; Sieczkowski, N; Roi, S; Vernhet, A

2015-01-21

240

Yeast: A Research Organism for Teaching Genetics.  

ERIC Educational Resources Information Center

Explains why laboratory strains of bakers yeast, Saccharomyces cerevisiae, are particularly suited for classroom science activities. Describes the sexual life cycle of yeast and the genetic system with visible mutations. Presents an overview of activities that can be done with yeast and gives a source for teachers to obtain more information. (PR)

Manney, Thomas R.; Manney, Monta L.

1992-01-01

241

The tiny difference between foraging and communication buzzes uttered by the Mexican free-tailed bat, Tadarida brasiliensis.  

PubMed

Echolocating insectivorous bats consummate prey captures using a distinct vocal motor pattern commonly known as the terminal or feeding buzz, which is widely considered a fixed motor pattern executed independently of auditory feedback influences. The Mexican free-tailed bat, Tadarida brasiliensis, offers an opportunity to explore the role of sensory feedback in buzzing because they emit similar buzzes both in flight during foraging and while stationary as communication sounds. Here we compared the spectral and temporal patterns of foraging and communication buzzes to address whether or not auditory feedback may influence buzz patterns. We found that while foraging buzzes uttered in open space were composed of generic FM calls, communication buzzes were composed of an adapted CF-FM call similar to the call type used by T. brasiliensis when navigating in confined spaces. This provides the first evidence that some bats can make significant context-dependent changes in the spectral parameters of calls within their buzz. We also found that inter-pulse intervals, but not call durations, were different within the two buzz types. These observations indicate that though a common pattern generator hierarchically organizes all buzzes, T. brasiliensis retains a significant capacity to adapt the spectral and temporal patterns of elements within its buzzes. PMID:17503051

Schwartz, Christine; Tressler, Jedidiah; Keller, Halli; Vanzant, Marc; Ezell, Sarah; Smotherman, Michael

2007-08-01

242

Lesions Associated with Halocercus brasiliensis Lins de Almeida, 1933 in the Lungs of Dolphins Stranded in the Northeast of Brazil.  

PubMed

The parasitic fauna of cetaceans is an important tool for ecological studies, including analyses on the causes of death. Halocercus brasiliensis is a nematode frequently found in the bronchi and bronchioles of some cetaceans, and it is commonly associated with focal inflammation of the respiratory tract leading to bacterial pneumonia and septicemia and, sometimes, to death. The objective of this study was to report infections by H. brasiliensis in the respiratory tract of Delphinidae stranded on the northern seaside of Bahia, Sergipe, and south of Alagoas, all states in the northeast region of Brazil. A total of 30 individuals, 1 Feresa attenuate (pygmy killer whale), 9 Stenella clymene (Clymene dolphin), and 20 Sotalia guianensis (Guiana dolphin) were studied. In 16 of them, the presence of H. brasiliensis was observed with a mean intensity of 3.5 ± 0.6 (range 1-9) in the hosts. Macroscopically, parasitic calcified nodules, lung congestion, edema, and emphysema were observed. Histopathological examination showed interstitial and granulomatous pneumonia with multifocal infiltrates, discrete to moderate edema, congestion, diffuse hemorrhage, and foci of calcification. We conclude that parasitic pneumonia in the sampled individuals may have directly contributed to stranding and death of the animals. PMID:25171594

Guimarães, J P; Febronio, A M B; Vergara-Parente, J E; Werneck, M R

2015-04-01

243

The left lung is preferentially targeted during experimental paracoccidioidomycosis in C57BL/6 mice  

PubMed Central

Paracoccidioidomycosis (PCM) is a chronic systemic mycosis caused by the inhalation of the thermally dimorphic fungus Paracoccidioides brasiliensis as well as the recently described P. lutzii. Because the primary infection occurs in the lungs, we investigated the differential involvement of the right and left lungs in experimental P. brasiliensis infection. Lungs were collected from C57BL/6 mice at 70 days after intravenous infection with 1×106 yeast cells of a virulent strain of P. brasiliensis (Pb18). The left lung, which in mice is smaller and has fewer lobes than the right lung, yielded increased fungal recovery associated with a predominant interleukin-4 response and diminished synthesis of interferon-? and nitric oxide compared with the right lung. Our data indicate differential involvement of the right and left lungs during experimental PCM. This knowledge emphasizes the need for an accurate, standardized protocol for tissue collection during studies of experimental P. brasiliensis infection, since experiments using the same lungs favor the collection of comparable data among different mice. PMID:24141611

Tristão, F.S.M.; Rocha, F.A.; Dias, F.C.; Rossi, M.A.; Silva, J.S.

2013-01-01

244

The Pivotal Role of 5-Lipoxygenase-Derived LTB4 in Controlling Pulmonary Paracoccidioidomycosis  

PubMed Central

Leukotrienes (LTs) produced from arachidonic acid by the action of 5-lipoxygenase (5-LO) are classical mediators of inflammatory responses. However, studies published in the literature regarding these mediators are contradictory and it remains uncertain whether these lipid mediators play a role in host defense against the fungal pathogen Paracoccidioides brasiliensis. To determine the involvement of LTs in the host response to pulmonary infection, wild-type and LT-deficient mice by targeted disruption of the 5-lipoxygenase gene (knockout mice) were studied following intratracheal challenge with P. brasiliensis yeasts. The results showed that infection is uniformly fatal in 5-LO-deficient mice and the mechanisms that account for this phenotype are an exacerbated lung injury and higher fungal pulmonary burden. Genetic ablation or pharmacological inhibition of LTs resulted in lower phagocytosis and fungicidal activity of macrophages in vitro, suggesting that deficiency in fungal clearance seems to be secondary to the absence of activation in 5-LO?/? macrophages. Exogenous LTB4 restored phagocytosis and fungicidal activity of 5-LO?/? macrophages. Moreover, P. brasiliensis killing promoted by LTB4 was dependent on nitric oxide (NO) production by macrophages. Taken together, these results reveal a fundamental role for 5-LO-derived LTB4 in the protective response to P. brasiliensis infection and identify relevant mechanisms for the control of fungal infection during the early stages of the host immune response. PMID:23991239

Santos, Patrícia Campi; Santos, Daniel Assis; Ribeiro, Lucas Secchim; Fagundes, Caio Tavares; de Paula, Talles Prosperi; Avila, Thiago Vinícius; Baltazar, Ludmila de Matos; Madeira, Mila Moreira; Cruz, Rosana de Carvalho; Dias, Ana Carolina Fialho; Machado, Fabiana Simão; Teixeira, Mauro Martins; Cisalpino, Patrícia Silva; Souza, Danielle G.

2013-01-01

245

Overexpression of multisubunit replication factors in yeast.  

PubMed

Facile genetic and biochemical manipulation coupled with rapid cell growth and low cost of growth media has established the yeast Saccharomyces cerevisiae as a versatile workhorse. This article describes the use of yeast expression systems for the overproduction of complex multipolypeptide replication factors. The regulated overexpression of these factors in yeast provides for a readily accessible and inexpensive source of these factors in large quantities. The methodology is illustrated with the five-subunit replication factor C. Whole-cell extracts are prepared by blending yeast cells with glass beads or frozen yeast with dry ice. Procedures are described that maximize the yield of these factors while minimizing proteolytic degradation. PMID:10454996

Burgers, P M

1999-07-01

246

Molecular Genetic Analysis in Yeast  

NSDL National Science Digital Library

This resource provides techniques and protocols used in basic and advanced procedures of recombinant DNA technology to perform molecular genetic analysis in the yeast Saccharomyces cerevisiae. Students will be exposed to techniques such as transformation, restriction endonuclease digestion, electrophoresis and Southern blot analysis.

Daniel D. Burke (Seton Hall University; )

1990-01-01

247

Barcoding the Yeasts – Which Genes?  

Technology Transfer Automated Retrieval System (TEKTRAN)

Old style yeast identification, as many know, is an onerous process requiring determination of growth reactions on 60-100 different media. Once completed, there is still a high degree of uncertainty about species identity. With the determination of sequences for domains 1 and 2 (D1/D2) of the nucl...

248

Yeast Proteomics and Protein Microarrays  

PubMed Central

Our understanding of biological processes as well as human diseases has improved greatly thanks to studies on model organisms such as yeast. The power of scientific approaches with yeast lies in its relatively simple genome, its facile classical and molecular genetics, as well as the evolutionary conservation of many basic biological mechanisms. However, even in this simple model organism, systems biology studies, especially proteomic studies had been an intimidating task. During the past decade, powerful high-throughput technologies in proteomic research have been developed for yeast including protein microarray technology. The protein microarray technology allows the interrogation of protein-protein, protein-DNA, protein-small molecule interaction networks as well as post-translational modification networks in a large-scale, high-throughput manner. With this technology, many groundbreaking findings have been established in studies with the budding yeast Saccharomyces cerevisiae, most of which could have been unachievable with traditional approaches. Discovery of these networks has profound impact on explicating biological processes with a proteomic point of view, which may lead to a better understanding of normal biological phenomena as well as various human diseases. PMID:20728591

Chen, Rui; Snyder, Michael

2010-01-01

249

Dual localization of Mdj1 in pathogenic fungi varies with growth temperature.  

PubMed

Paracoccidioides brasiliensis and P. lutzii are temperature-dependent dimorphic fungi that cause paracoccidioidomycosis (PCM). Previously, we characterized the PbMDJ1 gene. This gene encodes P. brasiliensis chaperone Mdj1, which in yeast is a mitochondrial member of the J-domain family, whose main function is to regulate cognate Hsp70 activities. We produced rabbit polyclonal antibody antirecombinant PbMdj1 (rPbMdj1), which labeled the protein not only in mitochondria but also at the cell wall of P. brasiliensis yeasts of isolate Pb18. Here we used anti-rPbMdj1 in confocal microscopy to localize Mdj1 in Pb18 and other fungal isolates grown at different temperatures. Dual intracellular and cell surface pattern were initially seen in yeast-phase P. brasiliensis Pb3, Pb18 (control), P. lutzii Pb01, and Histoplasma capsulatum. Pb18 and Aspergillus fumigatus hyphae as well as Pb3 pseudo hyphae formed at 36°C were labeled predominantly along the cell surface. Preferential surface localization was observed by 72 h of yeast-mycelium thermotransition. It was interesting to observe that anti-rPbMdj1 concentrated at the surface tip and branching points of A. fumigatus hyphae grown at 36°C, suggesting a role in growth, whereas at 23°C, anti-rPbMdj1 was distributed along the hyphal surface. In Pb3, Pb18, and Pb01 mitochondrial extracts, the antibodies revealed a specific 55-kDa band, which corresponds to the processed Mdj1 size. The presence of Mdj1 on the fungal cell wall suggests that this protein could also play a role in the interaction with the host. PMID:24577000

Dourado, Itala Bruna Z; Batista, Wagner L; Longo, Larissa V G; Mortara, Renato A; Puccia, Rosana

2014-02-01

250

[Heterologous interferons synthesis in yeast Pichia pastoris].  

PubMed

The HuIFNA16, HuIFNB, and BoIFNG genes encoding human [alpha]16, beta-interferons and bovine gamma-interferon were cloned under the control of the yeast Pichia pastoris AOX1 gene promoter. The yeast strains producing heterologous interferons intracellularly and extracellularly were constructed. There was no effect of high level of heterologous protein synthesis on the yeast P. pastoris cell growth, unlike yeast Saccharomyces cerevisiae. The considerable part of the heterologous interferons was detected in the yeast P. pastoris soluble protein fraction but not in the "inclusion bodies." The treatment of human beta-interferon with endoglycosidase H showed that protein was expressed in glycosilated and unglycosilated forms. On the strength of these data, the hypothesis was suggested that the more effective heterologous gene expression in yeast P. pastoris and enhanced resistance of the methylotrophic yeast to negative effects of recombinant proteins was due to the special features of its metabolism. PMID:20873170

Padkina, M V; Parfenova, L V; Gradoboeva, A E; Sambuk, E V

2010-01-01

251

Acaulospora brasiliensis comb. nov. and Acaulospora alpina (Glomeromycota) from upland Scotland: morphology, molecular phylogeny and DNA-based detection in roots.  

PubMed

Spores of two supposedly arbuscular mycorrhizal fungal species, new to the United Kingdom and recently described as Acaulospora alpina and Ambispora brasiliensis (Glomeromycota), were discovered in soil samples from moorland in upland Scotland. Soil and plant trap pot cultures were established, but attempts to establish these fungi in single-species pot cultures with Plantago lanceolata as host were unsuccessful. Nevertheless, based on a 1.5-kb DNA fragment spanning part of the small subunit rRNA gene, the internal transcribed spacer region and part of the large subunit rRNA gene, both these species could be detected directly in field-sampled roots, together with one uncultured species each of Scutellospora, Rhizophagus (former Glomus group Ab, or 'Glomus intraradices clade') and Acaulospora. Whereas A. alpina has characteristic morphological similarities to other species in its genus, A. brasiliensis morphologically has little in common with any other species in Ambispora. The molecular phylogeny, DNA barcoding and morphological evidence clearly place A. brasiliensis in the genus Acaulospora. We therefore rename the species, reported from Brazil and Scotland, as Acaulospora brasiliensis comb. nov., and discuss ecological aspects of the very different environments from which A. brasiliensis and A. alpina have been reported. PMID:21336507

Krüger, Manuela; Walker, Christopher; Schüssler, Arthur

2011-08-01

252

Antinociceptive and anti-inflammatory properties of 7-epiclusianone, a prenylated benzophenone from Garcinia brasiliensis.  

PubMed

7-Epiclusianone, a natural prenylated benzophenone, was extracted from Garcinia brasiliensis Planch. & Triana (Clusiaceae), a native plant commonly known as bacupari and used in traditional Brazilian medicine for the treatment of inflammatory diseases. As a result of the wide spectrum of biological activities attributed to polyisoprenylated benzophenones, the aim of this study was to evaluate the analgesic and anti-inflammatory effects of 7-epiclusianone using two animal models. Carrageenan-induced paw oedema and peritonitis were used to investigate the anti-inflammatory activity of 7-epiclusianone in rats. The acetic acid-induced writhing, formalin and hot-plate tests were used to investigate its antinociceptive activity in mice. At test doses of 5, 10 and 15 mg/kg p.o., 7-epiclusianone had an anti-inflammatory effect as demonstrated by the reduction of paw oedema induced by carrageenan and the inhibition of leukocyte recruitment into the peritoneal cavity. At the same doses, 7-epiclusianone inhibited nociception induced by an intraperitoneal injection of acetic acid, observed by the decrease in the number of writhing episodes. Additionally, 7-epiclusianone decreased licking time caused by a subplantar injection of formalin. Moreover, the hot plate test produced a significant increase in latency reaction, demonstrating an antinociceptive effect. The experimental data demonstrated that the polyisoprenylated benzophenone 7-epiclusianone has remarkable anti-inflammatory and antinociceptive activities. PMID:21924261

Santa-Cecília, Flávia V; Freitas, Lissara A S; Vilela, Fabiana C; Veloso, Clarice de C; da Rocha, Cláudia Q; Moreira, Maria E C; Dias, Danielle F; Giusti-Paiva, Alexandre; dos Santos, Marcelo H

2011-11-16

253

Cloning and characterization of a novel cysteine protease gene (HbCP1) from Hevea brasiliensis.  

PubMed

The full-length cDNA encoding a cysteine protease,designated HbCP1, was isolated for the first time from Hevea brasiliensis by the rapid amplification of cDNA ends (RACE) method. HbCP1 contained a 1371 bp open reading frame encoding 457 amino acids.The deduced HbCP1 protein,which showed high identity to cysteine proteases of other plant species,was predicted to possess a putative repeat in toxin (RTX) domain at the N-terminal and a granulin (GRAN) domain at the C-terminal.Southern blot analysis indicated that the HbCP1 gene is present as a single copy in the rubber tree.Transcription pattern analysis revealed that HbCP1 had high transcription in laticifer,and low transcription in bark and leaf.The transcription of HbCP1 in latex was induced by ethylene and tapping.Cloning of the HbCP1 gene will enable us to further understand the molecular characterization of cysteine protease and its possible function in the rubber tree. PMID:19179756

Peng, Shi-Qing; Zhu, Jia-Hong; Li, Hui-Liang; Tian, Wei-Min

2008-12-01

254

Rubber elongation factor (REF), a major allergen component in Hevea brasiliensis latex has amyloid properties.  

PubMed

REF (Hevb1) and SRPP (Hevb3) are two major components of Hevea brasiliensis latex, well known for their allergenic properties. They are obviously taking part in the biosynthesis of natural rubber, but their exact function is still unclear. They could be involved in defense/stress mechanisms after tapping or directly acting on the isoprenoid biosynthetic pathway. The structure of these two proteins is still not described. In this work, it was discovered that REF has amyloid properties, contrary to SRPP. We investigated their structure by CD, TEM, ATR-FTIR and WAXS and neatly showed the presence of ?-sheet organized aggregates for REF, whereas SRPP mainly fold as a helical protein. Both proteins are highly hydrophobic but differ in their interaction with lipid monolayers used to mimic the monomembrane surrounding the rubber particles. Ellipsometry experiments showed that REF seems to penetrate deeply into the monolayer and SRPP only binds to the lipid surface. These results could therefore clarify the role of these two paralogous proteins in latex production, either in the coagulation of natural rubber or in stress-related responses. To our knowledge, this is the first report of an amyloid formed from a plant protein. This suggests also the presence of functional amyloid in the plant kingdom. PMID:23133547

Berthelot, Karine; Lecomte, Sophie; Estevez, Yannick; Coulary-Salin, Bénédicte; Bentaleb, Ahmed; Cullin, Christophe; Deffieux, Alain; Peruch, Frédéric

2012-01-01

255

Diversity of the cassiicolin gene in Corynespora cassiicola and relation with the pathogenicity in Hevea brasiliensis.  

PubMed

Corynespora cassiicola is an important plant pathogenic Ascomycete causing the damaging Corynespora Leaf Fall (CLF) disease in rubber tree (Hevea brasiliensis). A small secreted glycoprotein named cassiicolin was previously described as an important effector of C. cassiicola. In this study, the diversity of the cassiicolin-encoding gene was analysed in C. cassiicola isolates sampled from various hosts and geographical origins. A cassiicolin gene was detected in 47 % of the isolates, encoding up to six distinct protein isoforms. In three isolates, two gene variants encoding cassiicolin isoforms Cas2 and Cas6 were found in the same isolate. A phylogenetic tree based on four combined loci and elucidating the diversity of the whole collection was strongly structured by the toxin class, as defined by the cassiicolin isoform. The isolates carrying the Cas1 gene (toxin class Cas1), all grouped in the same highly supported clade, were found the most aggressive on two rubber tree cultivars. Some isolates in which no Cas gene was detected could nevertheless generate moderate symptoms, suggesting the existence of other yet uncharacterized effectors. This study provides a useful base for future studies of C. cassiicola population biology and epidemiological surveys in various host plants. PMID:24433675

Déon, Marine; Fumanal, Boris; Gimenez, Stéphanie; Bieysse, Daniel; Oliveira, Ricardo R; Shuib, Siti Shuhada; Breton, Frédéric; Elumalai, Sunderasan; Vida, João B; Seguin, Marc; Leroy, Thierry; Roeckel-Drevet, Patricia; Pujade-Renaud, Valérie

2014-01-01

256

A novel and enantioselective epoxide hydrolase from Aspergillus brasiliensis CCT 1435: purification and characterization.  

PubMed

A novel epoxide hydrolase from Aspergillus brasiliensis CCT1435 (AbEH) was cloned and overexpressed in Escherichia coli cells with a 6xHis-tag and purified by nickel affinity chromatography. Gel filtration analysis and circular dichroism measurements indicated that this novel AbEH is a homodimer in aqueous solution and contains the typical secondary structure of an ?/? hydrolase fold. The activity of AbEH was initially assessed using the fluorogenic probe O-(3,4-epoxybutyl) umbelliferone and was active in a broad range of pH (6-9) and temperature (25-45°C); showing optimum performance at pH 6.0 and 30°C. The Michaelis constant (KM) and maximum rate (Vmax) values were 495?M and 0.24?M/s, respectively. Racemic styrene oxide (SO) was used as a substrate to assess the AbEH activity and enantioselectivity, and 66% of the SO was hydrolyzed after only 5min of reaction, with the remaining (S)-SO ee exceeding 99% in a typical kinetic resolution behavior. The AbEH-catalyzed hydrolysis of SO was also evaluated in a biphasic system of water:isooctane; (R)-diol in 84% ee and unreacted (S)-SO in 36% ee were produced, with 43% conversion in 24h, indicating a discrete enantioconvergent behavior for AbEH. This novel epoxide hydrolase has biotechnological potential for the preparation of enantiopure epoxides or vicinal diols. PMID:23973866

Beloti, Lilian L; Costa, Bruna Z; Toledo, Marcelo A S; Santos, Clelton A; Crucello, Aline; Fávaro, Marianna T P; Santiago, André S; Mendes, Juliano S; Marsaioli, Anita J; Souza, Anete P

2013-10-01

257

Effects of DDE on experimentally poisoned free-tailed bats (Tadarida brasiliensis): Lethal brain concentrations  

USGS Publications Warehouse

Adult female free-tailed bats (Tadarida brasiliensis) were collected at Bracken Cave, Texas, and shipped to the Patuxent Wildlife Research Center. Treated mealworms (Tenebrio molitor) containing 107 ppm DDE were fed to 17 bats; five other bats were fed untreated mealworms. After 40 days on dosage, during which one dosed bat was killed accidentally, four dosed bats were frozen and the remaining 17 were starved to death. The objective was to elevate brain levels of DDE to lethality and measure these concentrations. After the feeding period, dosed bats weighed less than controls. After starvation, the body condition of dosed bats was poorer than that of controls even though there was no difference in the amounts of carcass fat. During starvation, dosed bats lost weight faster than controls. Also, four dosed bats exhibited the prolonged tremoring that characterizes DDE poisoning. DDE increased in brains of starving bats as fat was metabolized. The estimated mean brain concentration of DDE diagnostic of death was 519 ppm with a range of 458-564 ppm. These values resemble diagnostic levels known for two species of passerine birds, but they exceed published levels for two free-tailed bats from Carlsbad Caverns, New Mexico.

Clark, D.R., Jr.; Kroll, J.C.

1977-01-01

258

Genetic and epigenetic uniformity of polyembryony derived multiple seedlings of Hevea brasiliensis.  

PubMed

Hevea brasiliensis Muell. Arg (Para rubber tree) is a tropical tree species of Amazonian origin widely cultivated in several parts of the world for natural rubber, a highly priced commodity inevitable for the world rubber industry. Large, tree to tree variation in growth and latex yield among individual plants of high yielding Hevea clones is a common phenomenon observed in mature rubber plantations. The genetic heterogeneity of the seedlings which are used as rootstocks for propagation through budgrafting is considered as a major factor  responsible for this variation. In order to minimize this variation, attempts were made to develop highly uniform rootstock material via an in vitro technique by inducing zygotic polyembryony in Hevea. Immature open pollinated fruits of a high yielding clone RRII 105 were cultured by half ovulo embryo culture technique. Multiple embryos were induced from the 8-10-week-old zygote with a novel combination of gibberellic acid (GA3), kinetin, and zeatin. Plantlets were successfully generated from the multiple embryos and raised in the field post hardening. Screening using genetic and epigenetic molecular markers revealed that the multiple seedlings developed are highly uniform and are of single zygotic origin. Development of plants having genetic and epigenetic uniformity suggests that this technique is ideal for raising uniform rootstock material in Hevea which may significantly reduce intraclonal variations. Moreover, these plants could serve as ideal material for physiological and molecular investigations towards the understanding of  stock-scion interaction process in rubber. PMID:25359186

Karumamkandathil, Rekha; Uthup, Thomas K; Sankaran, Sobha; Unnikrishnan, Divya; Saha, Thakurdas; Nair, Sushamakumari S

2014-10-31

259

Defense-related polyphenol oxidase from Hevea brasiliensis cell suspension: purification and characterization.  

PubMed

Polyphenol oxidase (PPO) was examined from the extract of leaf, seed, and cell suspension of Hevea brasiliensis, a rubber plant. The defense-related isozyme from Hevea cell suspension induced by culture filtrate of Phytophthora palmivora or by agitation stress was isolated through anion exchange and affinity chromatography, respectively. A 104-purification fold, migrated as a single band of 70 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis of PPO, was obtained after further purified by the preparative gel electrophoresis. Based on reaction with catechol and dopamine but not with p-cresol and guaiacol, it is a diphenol-type PPO. The values of V(max)/K(m) ratio indicated that catechol was the most specific substrate. The optimal activity of the purified PPO was observed at pH 6.0. The PPO activity was retained at pH 4.0-10.0 and temperature 10-60 °C. The inhibitors which completely inhibited the activity were ascorbic acid, dithiothreitol, and ?-mercaptoethanol while sodium azide was a poor inhibitor. The PPO obtained from Hevea cell suspension possesses high specific activity and is stable at wide range of pH and temperature. It is therefore suitable for extreme condition uses and may lead to an alternative source of PPO in various industrial applications. PMID:22532343

Muhamad, Nisaporn; Chirapongsatonkul, Nion; Churngchow, Nunta

2012-05-01

260

Hevea brasiliensis cell suspension peroxidase: purification, characterization and application for dye decolorization  

PubMed Central

Peroxidases are oxidoreductase enzymes produced by most organisms. In this study, a peroxidase was purified from Hevea brasiliensis cell suspension by using anion exchange chromatography (DEAE-Sepharose), affinity chromatography (Con A-agarose) and preparative SDS-PAGE. The obtained enzyme appeared as a single band on SDS-PAGE with molecular mass of 70 kDa. Surprisingly, this purified peroxidase also had polyphenol oxidase activity. However, the biochemical characteristics were only studied in term of peroxidase because similar experiments in term of polyphenol oxidase have been reported in our pervious publication. The optimal pH of the purified peroxidase was 5.0 and its activity was retained at pH values between 5.0–10.0. The enzyme was heat stable over a wide range of temperatures (0–60°C), and less than 50% of its activity was lost at 70°C after incubation for 30 min. The enzyme was completely inhibited by ?-mercaptoethanol and strongly inhibited by NaN3; in addition, its properties indicated that it was a heme containing glycoprotein. This peroxidase could decolorize many dyes; aniline blue, bromocresol purple, brilliant green, crystal violet, fuchsin, malachite green, methyl green, methyl violet and water blue. The stability against high temperature and extreme pH supported that the enzyme could be a potential peroxidase source for special industrial applications. PMID:23402438

2013-01-01

261

Hevea brasiliensis cell suspension peroxidase: purification, characterization and application for dye decolorization.  

PubMed

Peroxidases are oxidoreductase enzymes produced by most organisms. In this study, a peroxidase was purified from Hevea brasiliensis cell suspension by using anion exchange chromatography (DEAE-Sepharose), affinity chromatography (Con A-agarose) and preparative SDS-PAGE. The obtained enzyme appeared as a single band on SDS-PAGE with molecular mass of 70 kDa. Surprisingly, this purified peroxidase also had polyphenol oxidase activity. However, the biochemical characteristics were only studied in term of peroxidase because similar experiments in term of polyphenol oxidase have been reported in our pervious publication. The optimal pH of the purified peroxidase was 5.0 and its activity was retained at pH values between 5.0-10.0. The enzyme was heat stable over a wide range of temperatures (0-60°C), and less than 50% of its activity was lost at 70°C after incubation for 30 min. The enzyme was completely inhibited by ?-mercaptoethanol and strongly inhibited by NaN3; in addition, its properties indicated that it was a heme containing glycoprotein. This peroxidase could decolorize many dyes; aniline blue, bromocresol purple, brilliant green, crystal violet, fuchsin, malachite green, methyl green, methyl violet and water blue. The stability against high temperature and extreme pH supported that the enzyme could be a potential peroxidase source for special industrial applications. PMID:23402438

Chanwun, Thitikorn; Muhamad, Nisaporn; Chirapongsatonkul, Nion; Churngchow, Nunta

2013-01-01

262

Fat content in migratory central Arizona Brazilian free-tailed bats, Tadarida brasiliensis (Molossidae)  

USGS Publications Warehouse

Fat content of migratory Tadarida brasiliensis was determined during the spring, summer and fall of 1972 in the Verde Valley of Arizona. Fat indices were highest in March arrivals, generally declined throughout the summer, and were lowest in September. In both 1972 and 1973 bats had arrived at the study area by mid-March. In 1971 bats were last noted at the area in mid-October while in 1972 they had disappeared by late September. On the basis on physiological calculations it is estimated that bats collected in March 1972 possessed sufficient fat reserves to carry them a mean distance of 716 km north of the study area while September bats had only enough reserves to fly 386 km southward, about 160 km short of the nearest known Sonora wintering locality. It is suggested that in spring the bats may have a more rigidly timed migration and so put on excess fat to counter an uncertain environment to the north. The fall migration may be triggered by more unpredictable events, such as the passage of cold fronts, and less fat reserves may be required for movements into more favorable southern locales.

O'Shea, Thomas J.

1976-01-01

263

Microtopography of Nippostrongylus brasiliensis (Nematoda: Heligmosomatidae): parasitic larval stages and adults.  

PubMed

Specimens of the rat hookworm, Nippostrongylus brasiliensis (Nematoda) were recovered from lungs (third- and fourth-stage larvae) and intestine (fourth-stage larvae and adults). The following features were studied in the different stages by scanning electron microscopy: cephalic structures, especially sense organs, synlophe, cervical region, and caudal part. The main differences between the third and fourth stages concerned the lip-like structures around the oral aperture, the appearance of the cephalic space with the presence of a cephalic cap in fourth-stage larvae, the pattern of longitudinal ridges, and sexual differentiation. Pore-like papillae, not seen in third-stage larvae, developed in later stages. Deirids were observed only in adults, and phasmids were poorly discerned. Some of these morphological features, such as the cephalic sense organ apertures and cuticle pores and micropores, can be observed only by scanning electron microscopy. The possible functions of these different structures and their relationship with the behavior of the worms during their life cycle are discussed. PMID:8230234

Nembo, B; Goudey-Perriere, F; Gayral, P; Perriere, C; Brousse-Gaury, P

1993-09-01

264

Aid to a declining matriarch in the giant otter (Pteronura brasiliensis).  

PubMed

Scientists are increasingly revealing the commonalities between the intellectual, emotional and moral capacities of animals and humans. Providing assistance to elderly and ailing family members is a human trait rarely documented for wild animals, other than anecdotal accounts. Here I report observations of multiple forms of assistance to the declining matriarch of a habituated group of giant otters (Pteronura brasiliensis) in Manu National Park, Peru. The otter group had been observed annually for several years and all members were known individually. In 2007, the breeding female of the group failed to reproduce and appeared to be in physical decline. She begged from other family members 43 times over 41 contact hours and received food 11 times. Comparisons with 2004-2006 demonstrate that the family's behavior in 2007 constitutes a role-reversal, in which the majority of assistance and prey transfers accrued from young-to-old rather than from old-to-young. As in human societies, both non-adaptive and adaptive hypotheses could explain the family members' aid to their declining matriarch. I suggest that giant otter families may benefit from the knowledge and experience of an elderly matriarch and "grandparent helper," consistent with the "Grandmother Hypothesis" of adaptive menopause in women. PMID:20613978

Davenport, Lisa C

2010-01-01

265

Rubber (Hevea brasiliensis) seed oil toxicity effect and Linamarin compound analysis  

PubMed Central

Background The lipid fraction of rubber (Hevea brasiliensis (kunth. Muell)) seed was extracted and analyzed for toxicological effect. The toxicological compound such as linamarin in rubber seed oil (RSO) extracted using different solvents, such as hexane (RSOh), mixture of chloroform?+?methanol (RSOchl+mth) and ethanol (RSOeth) were also studied. Various methods analysis such as Fourier transforms infrared spectroscopy (FTIR) and colorimetric methods were carried out to determine the present of such compounds. Results FTIR spectrum of RSO did not show any presence of cyanide peak. The determination of cyanide by using colorimetric method was demonstrated no response of the cyanide in RSO and didn’t show any colored comparing with commercial cyanide which observed blue color. The results showed that no functional groups such as cyanide (C???N) associated with linamarin were observed. Toxicological test using rats was also conducted to further confirm the absence of such compounds. RSO did not show any toxic potential to the rats. Bioassay experiments using shrimps had been used as test organisms to evaluate the toxicity of linamarin extract from RSOh, RSOchl+mth and RSOeth and LC50 were found to be (211.70?%, 139.40?%, and 117.41?%, respectively). Conclusions This can be attributed no hazardous linamarin were found in RSO. PMID:22694753

2012-01-01

266

Pheromone Signaling Pathways in Yeast  

NSDL National Science Digital Library

The actions of many extracellular stimuli are elicited by complexes of cell surface receptors, heterotrimeric guanine nucleotide–binding proteins (G proteins), and mitogen-activated protein kinase (MAPK) complexes. Analysis of haploid yeast cells and their response to peptide mating pheromones has produced important advances in the understanding of G protein and MAPK signaling mechanisms. Many of the components, their interrelationships, and their regulators were first identified in yeast. Examples include definitive demonstration of a positive signaling role for G protein ?? subunits, the discovery of a three-tiered structure of the MAPK module, development of the concept of a kinase-scaffold protein, and the discovery of the first regulator of G protein signaling protein. New and powerful genomic, proteomic, and computational approaches available in yeast are beginning to uncover new pathway components and interactions and have revealed their presence in unexpected locations within the cell. This updated Connections Map in the Database of Cell Signaling includes several major revisions to this prototypical signal response pathway.

Henrik G. Dohlman (University of North Carolina; Department of Biochemistry and Biophysics REV)

2006-12-05

267

Yeasts Diversity in Fermented Foods and Beverages  

NASA Astrophysics Data System (ADS)

People across the world have learnt to culture and use the essential microorganisms for production of fermented foods and alcoholic beverages. A fermented food is produced either spontaneously or by adding mixed/pure starter culture(s). Yeasts are among the essential functional microorganisms encountered in many fermented foods, and are commercially used in production of baker's yeast, breads, wine, beer, cheese, etc. In Asia, moulds are predominant followed by amylolytic and alcohol-producing yeasts in the fermentation processes, whereas in Africa, Europe, Australia and America, fermented products are prepared exclusively using bacteria or bacteria-yeasts mixed cultures. This chapter would focus on the varieties of fermented foods and alcoholic beverages produced by yeasts, their microbiology and role in food fermentation, widely used commercial starters (pilot production, molecular aspects), production technology of some common commercial fermented foods and alcoholic beverages, toxicity and food safety using yeasts cultures and socio-economy

Tamang, Jyoti Prakash; Fleet, Graham H.

268

Biopharmaceutical discovery and production in yeast.  

PubMed

The selection of an expression platform for recombinant biopharmaceuticals is often centered upon suitable product titers and critical quality attributes, including post-translational modifications. Although notable differences between microbial, yeast, plant, and mammalian host systems exist, recent advances have greatly mitigated any inherent liabilities of yeasts. Yeast expression platforms are important to both the supply of marketed biopharmaceuticals and the pipelines of novel therapeutics. In this review, recent advances in yeast-based expression of biopharmaceuticals will be discussed. The advantages of using glycoengineered yeast as a production host and in the discovery space will be illustrated. These advancements, in turn, are transforming yeast platforms from simple production systems to key technological assets in the discovery and selection of biopharmaceutical lead candidates. PMID:25014890

Meehl, Michael A; Stadheim, Terrance A

2014-12-01

269

Metabolic engineering of malolactic wine yeast.  

PubMed

Malolactic fermentation is essential for the deacidification of high acid grape must. We have constructed a genetically stable industrial strain of Saccharomyces cerevisiae by integrating a linear cassette containing the Schizosaccharomyces pombe malate permease gene (mae1) and the Oenococcus oeni malolactic gene (mleA) under control of the S. cerevisiae PGK1 promoter and terminator sequences into the URA3 locus of an industrial wine yeast. The malolactic yeast strain, ML01, fully decarboxylated 5.5 g/l of malate in Chardonnay grape must during the alcoholic fermentation. Analysis of the phenotype, genotype, transcriptome, and proteome revealed that the ML01 yeast is substantially equivalent to the parental industrial wine yeast. The ML01 yeast enjoys 'Generally Regarded As Safe' status from the FDA and is the first genetically enhanced yeast that has been commercialized. Its application will prevent the formation of noxious biogenic amines produced by lactic acid bacteria in wine. PMID:16621641

Husnik, John I; Volschenk, Heinrich; Bauer, Jurgen; Colavizza, Didier; Luo, Zongli; van Vuuren, Hennie J J

2006-07-01

270

Physiological properties of some yeast strains.  

PubMed

Twenty yeast strains have recently been isolated in pure cultures from natural and industrial sources and identified based mainly on physiological properties. The majority of the strains (15) are alcohologenic belonging to the genus Saccharomyces and comprise two brewer's (beer) yeast strains (S. carlsbergensis= S. uvarum A and B), two baker's yeast strains (S. cerevisiae CA and CP), one spirit yeast strain (S. cerevisiae CF) and ten wine yeast strains (S. cerevisiae var. ellipsoideus = S. ellipsoideus 1, 3, 4, 6, 8 and 9; S. oviformis 2, 5 and 7; and S. uvarum 10). The other 5 yeast strains belong to different species: Kloeckera apiculate, Candida mycoderma (Mycoderma vini), Pichia membranaefaciens, Rhodotorula glutinis and Torulopsis holmii, respectively. PMID:16841476

Oprean, Letitia; Gaspar, Enikö; Lengyel, Ecaterina; Cristea, V

2006-06-01

271

Histochemical study of the hepatopancreas in adult females of the pink-shrimp Farfantepenaeus brasiliensis Latreille, 1817.  

PubMed

This study provides histochemical data of the hepatopancreatic cells of adult female pink-shrimp (Farfantepenaeus brasiliensis) at two different developmental stages (those with developed gonads and those with exhausted gonads). The F. brasiliensis females were collected in seawater off the Guarapari coast, Espirito Santo, Brazil. Five cell types were identified in this digestive gland: B (vesicular), E (embryonic), F (fibrillar), M (basal) and R (resorptive). The digestive gland was stained with the following techniques: PAS/Alcian blue (for polysaccharides), bromophenol blue (for protein), von Kossa (for bound calcium) and Baker (for lipids). Acid glycoconjugates were found inside vacuoles in the R cells, while neutral polysaccharides were present in the B cells and near to the microvilli. In females with exhausted gonads polysaccharides were also seen in the intertubular spaces and inside the lumina of the tubules. The F and M cells were the most marked by the presence of large amounts of proteins observed in R cells and also inside the vacuoles of B cells. The bound calcium was mainly found in the F and M cells. The F cells showed strong positive staining for lipid while the R cell only stained weakly. The E cells did not react to any of the applied staining techniques. The similarities in the histochemical composition of these hepatopancreatic cells in females with developed gonads, compared to exhausted ones, is justified by the fact that transfer of these elements to the oocytes occurs, in significant quantity, only during the initial stages of gonadal development in F. brasiliensis. Also, they may be more related to the molt stage, as in the case of calcium salts. PMID:23992941

Nunes, Erika Takagi; Braga, Adriane Araújo; Camargo-Mathias, Maria Izabel

2014-01-01

272

De Novo Assembly and Transcriptome Analysis of the Rubber Tree (Hevea brasiliensis) and SNP Markers Development for Rubber Biosynthesis Pathways  

PubMed Central

Hevea brasiliensis (Willd. Ex Adr. Juss.) Muell.-Arg. is the primary source of natural rubber that is native to the Amazon rainforest. The singular properties of natural rubber make it superior to and competitive with synthetic rubber for use in several applications. Here, we performed RNA sequencing (RNA-seq) of H. brasiliensis bark on the Illumina GAIIx platform, which generated 179,326,804 raw reads on the Illumina GAIIx platform. A total of 50,384 contigs that were over 400 bp in size were obtained and subjected to further analyses. A similarity search against the non-redundant (nr) protein database returned 32,018 (63%) positive BLASTx hits. The transcriptome analysis was annotated using the clusters of orthologous groups (COG), gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Pfam databases. A search for putative molecular marker was performed to identify simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). In total, 17,927 SSRs and 404,114 SNPs were detected. Finally, we selected sequences that were identified as belonging to the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways, which are involved in rubber biosynthesis, to validate the SNP markers. A total of 78 SNPs were validated in 36 genotypes of H. brasiliensis. This new dataset represents a powerful information source for rubber tree bark genes and will be an important tool for the development of microsatellites and SNP markers for use in future genetic analyses such as genetic linkage mapping, quantitative trait loci identification, investigations of linkage disequilibrium and marker-assisted selection. PMID:25048025

Mantello, Camila Campos; Cardoso-Silva, Claudio Benicio; da Silva, Carla Cristina; de Souza, Livia Moura; Scaloppi Junior, Erivaldo José; de Souza Gonçalves, Paulo; Vicentini, Renato; de Souza, Anete Pereira

2014-01-01

273

De novo assembly and transcriptome analysis of the rubber tree (Hevea brasiliensis) and SNP markers development for rubber biosynthesis pathways.  

PubMed

Hevea brasiliensis (Willd. Ex Adr. Juss.) Muell.-Arg. is the primary source of natural rubber that is native to the Amazon rainforest. The singular properties of natural rubber make it superior to and competitive with synthetic rubber for use in several applications. Here, we performed RNA sequencing (RNA-seq) of H. brasiliensis bark on the Illumina GAIIx platform, which generated 179,326,804 raw reads on the Illumina GAIIx platform. A total of 50,384 contigs that were over 400 bp in size were obtained and subjected to further analyses. A similarity search against the non-redundant (nr) protein database returned 32,018 (63%) positive BLASTx hits. The transcriptome analysis was annotated using the clusters of orthologous groups (COG), gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Pfam databases. A search for putative molecular marker was performed to identify simple sequence repeats (SSRs) and single nucleotide polymorphisms (SNPs). In total, 17,927 SSRs and 404,114 SNPs were detected. Finally, we selected sequences that were identified as belonging to the mevalonate (MVA) and 2-C-methyl-D-erythritol 4-phosphate (MEP) pathways, which are involved in rubber biosynthesis, to validate the SNP markers. A total of 78 SNPs were validated in 36 genotypes of H. brasiliensis. This new dataset represents a powerful information source for rubber tree bark genes and will be an important tool for the development of microsatellites and SNP markers for use in future genetic analyses such as genetic linkage mapping, quantitative trait loci identification, investigations of linkage disequilibrium and marker-assisted selection. PMID:25048025

Mantello, Camila Campos; Cardoso-Silva, Claudio Benicio; da Silva, Carla Cristina; de Souza, Livia Moura; Scaloppi Junior, Erivaldo José; de Souza Gonçalves, Paulo; Vicentini, Renato; de Souza, Anete Pereira

2014-01-01

274

Spatial analysis of egg distribution and geographic changes in the spawning habitat of the Brazilian sardine Sardinella brasiliensis.  

PubMed

This paper establishes the spawning habitat of the Brazilian sardine Sardinella brasiliensis and investigates the spatial variability of egg density and its relation with oceanographic conditions in the shelf of the south-east Brazil Bight (SBB). The spawning habitats of S. brasiliensis have been defined in terms of spatial models of egg density, temperature-salinity plots, quotient (Q) analysis and remote sensing data. Quotient curves (Q(C)) were constructed using the geographic distribution of egg density, temperature and salinity from samples collected during nine survey cruises between 1976 and 1993. The interannual sea surface temperature (SST) variability was determined using principal component analysis on the SST anomalies (SSTA) estimated from remote sensing data over the period between 1985 and 2007. The spatial pattern of egg occurrences in the SBB indicated that the largest concentration occurred between Paranaguá and São Sebastião. Spawning habitat expanded and contracted during the years, fluctuating around Paranaguá. In January 1978 and January 1993, eggs were found nearly everywhere along the inner shelf of the SBB, while in January 1988 and 1991 spawning had contracted to their southernmost position. The SSTA maps for the spawning periods showed that in the case of habitat expansion (1993 only) anomalies over the SBB were zero or slightly negative, whereas for the contraction period anomalies were all positive. Sardinella brasiliensis is capable of exploring suitable spawning sites provided by the entrainment of the colder and less-saline South Atlantic Central Water onto the shelf by means of both coastal wind-driven (to the north-east of the SBB) and meander-induced (to the south-west of the SBB) upwelling. PMID:21155781

Gigliotti, E S; Gherardi, D F M; Paes, E T; Souza, R B; Katsuragawa, M

2010-12-01

275

Screening for l -arabinose fermenting yeasts  

Microsoft Academic Search

Utilization of pentose sugars (d-xylose andl-arabinose) derived from hemi-cellulose is essential for the economic conversion of biomass to ethanol. Xylose-fermenting\\u000a yeasts were discovered in the 1980s, but to date, no yeasts have been found that fermentl-arabinose to ethanol in significant quantities. We have screened 116 different yeasts for the ability to fermentl-arabinose and have found the following species able to

Bruce S. Dien; Cletus P. Kurtzman; Badal C. Saha; Rodney J. Bothast

1996-01-01

276

Characterisation of yeast microbial fuel cell with the yeast Arxula adeninivorans as the biocatalyst  

Microsoft Academic Search

Yeast microbial fuel cells have received little attention to date. Yeast should be ideal MFC catalyst because they are robust, easily handled, mostly non-pathogenic organisms with high catabolic rates and in some cases a broad substrate spectrum. Here we show that the non-conventional yeast Arxula adeninvorans transfers electrons to an electrode through the secretion of a reduced molecule that is

Nicholas D. Haslett; Frankie J. Rawson; Frèdèric Barriëre; Gotthard Kunze; Neil Pasco; Ravi Gooneratne; Keith H. R. Baronian

2011-01-01

277

Presence of glucosylceramide in yeast and its relation to alkali tolerance of yeast  

Microsoft Academic Search

Glycosylceramide is a membrane lipid that has physiological functions in eukaryotic organisms. The presence of glucosylceramide has been confirmed in some yeast; however, the extent of the role of glucosylceramide in yeast is unknown. Thus, the extent of presence of glucosylceramide in yeast was surveyed using 90 strains of 24 genera. The strains were divided into two groups according to

Katsuichi Saito; Naoya Takakuwa; Masao Ohnishi; Yuji Oda

2006-01-01

278

APPENDIX 4LGrowth and Manipulation of Yeast PREPARATION OF SELECTED YEAST MEDIA  

E-print Network

no nutritional require- ments. However, it is used most often as a basal medium to which other supplementsAPPENDIX 4LGrowth and Manipulation of Yeast PREPARATION OF SELECTED YEAST MEDIA Like Escherichia coli, yeast can be grown in either liquid media or on the surface of (or embedded in) solid agar plates

Winston, Fred

279

Evaluation of Automated Yeast Identification System  

NASA Technical Reports Server (NTRS)

One hundred and nine teleomorphic and anamorphic yeast isolates representing approximately 30 taxa were used to evaluate the accuracy of the Biolog yeast identification system. Isolates derived from nomenclatural types, environmental, and clinica isolates of known identity were tested in the Biolog system. Of the isolates tested, 81 were in the Biolog database. The system correctly identified 40, incorrectly identified 29, and was unable to identify 12. Of the 28 isolates not in the database, 18 were given names, whereas 10 were not. The Biolog yeast identification system is inadequate for the identification of yeasts originating from the environment during space program activities.

McGinnis, M. R.

1996-01-01

280

Role of glucose signaling in yeast metabolism  

SciTech Connect

The conversion of glucose to ethanol and carbon dioxide by yeast was the first biochemical pathway to be studied in detail. The initial observation that this process is catalyzed by an extract of yeast led to the discovery of enzymes and coenzymes and laid the foundation for modern biochemistry. In this article, knowledge concerning the relation between uptake of and signaling by glucose in the yeast Saccharomyces cerevisiae is reviewed and compared to the analogous process in prokaryotes. It is concluded that (much) more fundamental knowledge concerning these processes is required before rational redesign of metabolic fluxes from glucose in yeast can be achieved.

Dam, K. van [Univ. of Amsterdam (Netherlands). E.C. Slater Inst.

1996-10-05

281

Physiological and Molecular Responses to Variation of Light Intensity in Rubber Tree (Hevea brasiliensis Muell. Arg.)  

PubMed Central

Light is one of most important factors to plants because it is necessary for photosynthesis. In this study, physiological and gene expression analyses under different light intensities were performed in the seedlings of rubber tree (Hevea brasiliensis) clone GT1. When light intensity increased from 20 to 1000 µmol m?2 s?1, there was no effect on the maximal quantum yield of photosystem II (PSII) photochemistry (Fv/Fm), indicating that high light intensity did not damage the structure and function of PSII reaction center. However, the effective photochemical quantum yield of PSII (Y(II)), photochemical quenching coefficient (qP), electron transfer rate (ETR), and coefficient of photochemical fluorescence quenching assuming interconnected PSII antennae (qL) were increased significantly as the light intensity increased, reached a maximum at 200 µmol m?2 s?1, but decreased from 400 µmol m?2 s?1. These results suggested that the PSII photochemistry showed an optimum performance at 200 µmol m?2 s?1 light intensity. The chlorophyll content was increased along with the increase of light intensity when it was no more than 400 µmol m?2 s?1. Since increasing light intensity caused significant increase in H2O2 content and decreases in the per unit activity of antioxidant enzymes SOD and POD, but the malondialdehyde (MDA) content was preserved at a low level even under high light intensity of 1000 µmol m?2 s?1, suggesting that high light irradiation did not induce membrane lipid peroxidation in rubber tree. Moreover, expressions of antioxidant-related genes were significantly up-regulated with the increase of light intensity. They reached the maximum expression at 400 µmol m?2 s?1, but decreased at 1000 µmol m?2 s?1. In conclusion, rubber tree could endure strong light irradiation via a specific mechanism. Adaptation to high light intensity is a complex process by regulating antioxidant enzymes activities, chloroplast formation, and related genes expressions in rubber tree. PMID:24586839

Wang, Li-feng

2014-01-01

282

Impact of age of rubber (Hevea brasiliensis) plantation on earthworm communities of West Tripura (India).  

PubMed

A comparative analysis of earthworm communities was carried out in the rubber plantations (Hevea brasiliensis) of different age groups in West Tripura to understand the impact of such exotic and monoculture plantation in biodiversity conservation. Earthworm communities were studied on monthly basis over a period of one year (2006-2007) in the 3, 10, 14, 20 and 25 year-old plantations. Among twelve earthworm species collected from the studied sites, six species belonged to Octochaetidae [Eutyphoeus assomensis Stephenson, Eutyphoeus comillahnus Michaelsen, Lennogaster chittagongensis (Stephensen), Octochaetona beatrix Gates, Dichogaster offinis Michaelsen, Lennogaster yeicus (Stephensen)], two species each to Megascolecidae [Metaphire houlleti (Perrier), Konchurio sp. 1] and Moniligastridae [Drowida nepalensis Michaelsen, Drawida papillifer papillifer Stephenson], one species each to Glossoscolecidae [Pontoscolex corethrurus (Muller)] and Ocnerodrilidae [Gordiodrilus elegans Beddard]. Exotic species P corethrurus, M. houlleti and native peregrine species like D. nepolensis and D. papillifer papillifer were distributed in all the age groups of plantation, while other species showed restricted distribution. P. corethrurus contributed more than 60% biomass and 70% density of earthworm communities in rubber plantation. With aging of rubber plantations both the densities and biomasses of earthworms increased. High contents of polyphenol, flavonoid and lignin in the litters of 3 and 10 year-old-rubber plantations through their effects on food intake, probably resulted to low biomass values of earthworms in those age groups of plantation. With further increase in the age of plantations beyond 10 years, polyphenol, flavonoid and lignin contents decreased. Accordingly the biomass of earthworms increased with increase in the age of plantation. Soil moisture increased with increase in the age of plantation and there was a good positive correlation between soil moisture and earthworm biomass (p < 0.01). Density, biomass and dominance of earthworms increased while species diversity, species richness and species evenness of earthworm community were decreased with increase in the age of rubber plantation. PMID:24006808

Chaudhuri, P S; Bhattacharjee, Subhalaxmi; Dey, Animesh; Chattopadhyay, Sharmila; Bhattacharya, Dipto

2013-01-01

283

Molecular cloning and characterization of a Mlo gene in rubber tree (Hevea brasiliensis).  

PubMed

Mlo gene encodes a plant-specific seven-transmembrane domain protein involved in a variety of cellular processes. In this study, a novel Mlo gene from rubber tree (Hevea brasiliensis), designated HbMlo1, was cloned by RT-PCR in rubber tree. The ORF of HbMlo1 was 1551bp in length, encoding a putative protein of 516 amino acids. HbMlo1 was a typical Mlo protein with seven-transmembrane domain. Sequence comparison between HbMlo1 and other Mlo proteins demonstrated that HbMlo1 shared the highest similarity with the Cucumis melo CmMlo1 and Arabidopsis thaliana AtMlo1 with 75.1% and 71.3% sequence identity, respectively. Phylogenetic analysis revealed that HbMlo1, CmMlo1, AtMlo1, AtMlo13, and AtMlo15 formed into the phylogenetic clade II with 100% bootstrap support value. HbMlo1 transcript exhibited tissue specificity, and it was preferentially expressed in leaf. Furthermore, the amount of HbMlo1 transcript was significantly induced by various phytohormones (including ethephon, methyl jasmonate, salicylic acid, abscisic acid, indole-3-acetic acid, and gibberellic acid), H2O2, and wounding treatments. Under drought stress, HbMlo1 exhibited a complex pattern of regulation. However, HbMlo1 expression did not significantly change during powdery mildew infection. These results suggested that HbMlo1 might play a role in phytohormone signaling and abiotic stress response processes in rubber tree. PMID:25506769

Qin, Bi; Zheng, Fucong; Zhang, Yu

2015-03-01

284

Three-dimensional structures of enzyme-substrate complexes of the hydroxynitrile lyase from Hevea brasiliensis.  

PubMed Central

The 3D structures of complexes between the hydroxynitrile lyase from Hevea brasiliensis (Hb-HNL) and several substrate and/or inhibitor molecules, including trichloracetaldehyde, hexafluoracetone, acetone, and rhodanide, were determined by X-ray crystallography. The complex with trichloracetaldehyde showed a covalent linkage between the protein and the inhibitor, which had apparently resulted from nucleophilic attack of the catalytic Ser80-Ogamma. All other complexes showed the substrate or inhibitor molecule merely hydrogen bonded to the protein. In addition, the native crystal structure of Hb-HNL was redetermined at cryo-temperature and at room temperature, eliminating previous uncertainties concerning residual electron density within the active site, and leading to the observation of two conserved water molecules. One of them was found to be conserved in all complex structures and appears to have mainly structural significance. The other water molecule is conserved in all structures except for the complex with rhodanide; it is hydrogen bonded to the imidazole of the catalytic His235 and appears to affect the Hb-HNL catalyzed reaction. The observed 3D structural data suggest implications for the enzyme mechanism. It appears that the enzyme-catalyzed cyanohydrin formation is unlikely to proceed via a hemiacetal or hemiketal intermediate covalently attached to the enzyme, despite the observation of such an intermediate for the complex with trichloracetaldehyde. Instead, the data are consistent with a mechanism where the incoming substrate is activated by hydrogen bonding with its carbonyl oxygen to the Ser80 and Thr11 hydroxy groups. A hydrogen cyanide molecule subsequently replaces a water molecule and is deprotonated presumably by the His235 base. Deprotonation is facilitated by the proximity of the positive charge of the Lys236 side chain. PMID:10548044

Zuegg, J.; Gruber, K.; Gugganig, M.; Wagner, U. G.; Kratky, C.

1999-01-01

285

Identification of novel microRNAs in Hevea brasiliensis and computational prediction of their targets  

PubMed Central

Background Plants respond to external stimuli through fine regulation of gene expression partially ensured by small RNAs. Of these, microRNAs (miRNAs) play a crucial role. They negatively regulate gene expression by targeting the cleavage or translational inhibition of target messenger RNAs (mRNAs). In Hevea brasiliensis, environmental and harvesting stresses are known to affect natural rubber production. This study set out to identify abiotic stress-related miRNAs in Hevea using next-generation sequencing and bioinformatic analysis. Results Deep sequencing of small RNAs was carried out on plantlets subjected to severe abiotic stress using the Solexa technique. By combining the LeARN pipeline, data from the Plant microRNA database (PMRD) and Hevea EST sequences, we identified 48 conserved miRNA families already characterized in other plant species, and 10 putatively novel miRNA families. The results showed the most abundant size for miRNAs to be 24 nucleotides, except for seven families. Several MIR genes produced both 20-22 nucleotides and 23-27 nucleotides. The two miRNA class sizes were detected for both conserved and putative novel miRNA families, suggesting their functional duality. The EST databases were scanned with conserved and novel miRNA sequences. MiRNA targets were computationally predicted and analysed. The predicted targets involved in "responses to stimuli" and to "antioxidant" and "transcription activities" are presented. Conclusions Deep sequencing of small RNAs combined with transcriptomic data is a powerful tool for identifying conserved and novel miRNAs when the complete genome is not yet available. Our study provided additional information for evolutionary studies and revealed potentially specific regulation of the control of redox status in Hevea. PMID:22330773

2012-01-01

286

Serotonergic innervation of the auditory brainstem of the Mexican free-tailed bat, Tadarida brasiliensis.  

PubMed

Anatomical and electrophysiological evidence suggests that serotonin alters the processing of sound in the auditory brainstem of many mammalian species. The Mexican free-tailed bat is a hearing specialist, like other microchiropteran bats. At the same time, many aspects of its auditory brainstem are similar to those in other mammals. This dichotomy raises an interesting question regarding the serotonergic innervation of the bat auditory brainstem: Is the serotonergic input to the auditory brainstem similar in bats and other mammals, or are there specializations in the serotonergic innervation of bats that may be related to their exceptional hearing capabilities? To address this question, we immunocytochemically labeled serotonergic fibers in the brainstem of the Mexican free-tailed bat, Tadarida brasiliensis. We found many similarities in the pattern of serotonergic innervation of the auditory brainstem in Tadarida compared with other mammals, but we also found two striking differences. Similarities to staining patterns in other mammals included a higher density of serotonergic fibers in the dorsal cochlear nucleus and in granule cell regions than in the ventral cochlear nucleus, a high density of fibers in some periolivary nuclei of the superior olive, and a higher density of fibers in peripheral regions of the inferior colliculus compared with its core. The two novel features of serotonergic innervation in Tadarida were a high density of fibers in the fusiform layer of the dorsal cochlear nucleus relative to surrounding layers and a relatively high density of serotonergic fibers in the low-frequency regions of the lateral and medial superior olive. PMID:11370012

Hurley, L M; Thompson, A M

2001-06-18

287

Genetic variation and migration in the Mexican free-tailed bat (Tadarida brasiliensis mexicana).  

PubMed

Incomplete lineage sorting can genetically link populations long after they have diverged, and will exert a more powerful influence on larger populations. The effects of this stochastic process can easily be confounded with those of gene flow, potentially leading to inaccurate estimates of dispersal capabilities or erroneous designation of evolutionarily significant units (ESUs). We have used phylogenetic, population genetic, and coalescent methods to examine genetic structuring in large populations of a widely dispersing bat species and to test hypotheses concerning the influences of coalescent stochasticity vs. gene flow. The Mexican free-tailed bat, Tadarida brasiliensis mexicana, exhibits variation in both migratory tendency and route over its range. Observations of the species' migratory behaviour have led to the description of behaviourally and geographically defined migratory groups, with the prediction that these groups compose structured gene pools. Here, we used mtDNA sequence analyses coupled with existing information from allozyme, banding, and natural history studies to evaluate hypotheses regarding the relationship between migration and genetic structure. Analyses of molecular variance revealed no significant genetic structuring of behaviourally distinct migratory groups. Demographic analyses were consistent with population growth, although the timing of population expansion events differs between migratory and nonmigratory populations. Hypotheses concerning the role of gene flow vs. incomplete lineage sorting on these data are explored using coalescent simulations. Our study demonstrates the importance of accounting for coalescent stochasticity in formulating phylogeographical hypotheses, and indicates that analyses that do not take such processes into account can lead to false conclusions regarding a species' phylogeographical history. PMID:15910338

Russell, A L; Medellín, R A; McCracken, G F

2005-06-01

288

Characterization and cytotoxic activity of sulfated derivatives of polysaccharides from Agaricus brasiliensis  

PubMed Central

Agaricus brasiliensis cell-wall polysaccharides isolated from fruiting body (FR) and mycelium (MI) and their respective sulfated derivatives (FR-S and MI-S) were chemically characterized using elemental analysis, TLC, FT-IR, NMR, HPLC, and thermal analysis. Cytotoxic activity was evaluated against A549 tumor cells by MTT and sulforhodamine assays. The average molecular weight (Mw) of FR and MI was estimated to be 609 and 310 kDa, respectively. FR-S (127 kDa) and MI-S (86 kDa) had lower Mw, probably due to hydrolysis occurred during the sulfation reaction. FR-S and MI-S presented ~14 % sulfur content in elemental analysis. Sulfation of samples was characterized by the appearance of two new absorption bands at 1253 and 810 cm?1 in the infrared spectra, related to S=O and C-S-O sulfate groups, respectively. Through 1H and 13C NMR analysis FR-S was characterized as a (1?6)-(1?3)-?-D-glucan fully sulfated at C-4 and C-6 terminal and partially sulfated at C-6 of (1?3)-?-D-glucan moiety. MI-S was shown to be a (1?3)-?-D-gluco-(1?2)-?-D-mannan, partially sulfated at C-2, C-3, C-4, and C-6, and fully sulfated at C-6 of the terminal residues. The combination of high degree of sulfation and low molecular weight was correlated with the increased cytotoxic activity (48 h of treatment) of both FR-S (EC50=605.6 ?g/mL) and MI-S (EC50=342.1 ?g/mL) compared to the non-sulfated polysaccharides FR and MI (EC50>1500 ?g/mL). PMID:23511057

Cardozo, F. T. G. S.; Camelini, C. M.; Cordeiro, M. N. S.; Mascarello, A.; Malagoli, B. G.; Larsen, I.; Rossi, M. J.; Nunes, R. J.; Braga, F. C.; Brandt, C.R.; Simões, C. M. O.

2014-01-01

289

Drosophila Regulate Yeast Density and Increase Yeast Community Similarity in a Natural Substrate  

PubMed Central

Drosophila melanogaster adults and larvae, but especially larvae, had profound effects on the densities and community structure of yeasts that developed in banana fruits. Pieces of fruit exposed to adult female flies previously fed fly-conditioned bananas developed higher yeast densities than pieces of the same fruits that were not exposed to flies, supporting previous suggestions that adult Drosophila vector yeasts to new substrates. However, larvae alone had dramatic effects on yeast density and species composition. When yeast densities were compared in pieces of the same fruits assigned to different treatments, fruits that developed low yeast densities in the absence of flies developed significantly higher yeast densities when exposed to larvae. Across all of the fruits, larvae regulated yeast densities within narrow limits, as compared to a much wider range of yeast densities that developed in pieces of the same fruits not exposed to flies. Larvae also affected yeast species composition, dramatically reducing species diversity across fruits, reducing variation in yeast communities from one fruit to the next (beta diversity), and encouraging the consistent development of a yeast community composed of three species of yeast (Candida californica, C. zemplinina, and Pichia kluvyeri), all of which were palatable to larvae. Larvae excreted viable cells of these three yeast species in their fecal pools, and discouraged the growth of filamentous fungi, processes which may have contributed to their effects on the yeast communities in banana fruits. These and other findings suggest that D. melanogaster adults and their larval offspring together engage in ‘niche construction’, facilitating a predictable microbial environment in the fruit substrates in which the larvae live and develop. PMID:22860093

Stamps, Judy A.; Yang, Louie H.; Morales, Vanessa M.; Boundy-Mills, Kyria L.

2012-01-01

290

YMDB: the Yeast Metabolome Database.  

PubMed

The Yeast Metabolome Database (YMDB, http://www.ymdb.ca) is a richly annotated 'metabolomic' database containing detailed information about the metabolome of Saccharomyces cerevisiae. Modeled closely after the Human Metabolome Database, the YMDB contains >2000 metabolites with links to 995 different genes/proteins, including enzymes and transporters. The information in YMDB has been gathered from hundreds of books, journal articles and electronic databases. In addition to its comprehensive literature-derived data, the YMDB also contains an extensive collection of experimental intracellular and extracellular metabolite concentration data compiled from detailed Mass Spectrometry (MS) and Nuclear Magnetic Resonance (NMR) metabolomic analyses performed in our lab. This is further supplemented with thousands of NMR and MS spectra collected on pure, reference yeast metabolites. Each metabolite entry in the YMDB contains an average of 80 separate data fields including comprehensive compound description, names and synonyms, structural information, physico-chemical data, reference NMR and MS spectra, intracellular/extracellular concentrations, growth conditions and substrates, pathway information, enzyme data, gene/protein sequence data, as well as numerous hyperlinks to images, references and other public databases. Extensive searching, relational querying and data browsing tools are also provided that support text, chemical structure, spectral, molecular weight and gene/protein sequence queries. Because of S. cervesiae's importance as a model organism for biologists and as a biofactory for industry, we believe this kind of database could have considerable appeal not only to metabolomics researchers, but also to yeast biologists, systems biologists, the industrial fermentation industry, as well as the beer, wine and spirit industry. PMID:22064855

Jewison, Timothy; Knox, Craig; Neveu, Vanessa; Djoumbou, Yannick; Guo, An Chi; Lee, Jacqueline; Liu, Philip; Mandal, Rupasri; Krishnamurthy, Ram; Sinelnikov, Igor; Wilson, Michael; Wishart, David S

2012-01-01

291

Experimental evolution in budding yeast  

NASA Astrophysics Data System (ADS)

I will discuss our progress in analyzing evolution in the budding yeast, Saccharomyces cerevisiae. We take two basic approaches. The first is to try and examine quantitative aspects of evolution, for example by determining how the rate of evolution depends on the mutation rate and the population size or asking whether the rate of mutation is uniform throughout the genome. The second is to try to evolve qualitatively novel, cell biologically interesting phenotypes and track the mutations that are responsible for the phenotype. Our efforts include trying to alter cell morphology, evolve multicellularity, and produce a biological oscillator.

Murray, Andrew

2012-02-01

292

Ants (Hymenoptera: Formicidae) in Vineyards That Are Infested or Uninfested With Eurhizococcus brasiliensis (Hemiptera: Margarodidae) in Southeastern Brazil.  

PubMed

The association between ants and mealybugs can result in damage to agriculture, including vineyards. In southern Brazil, the ant Linepithema micans F. contributes to the dispersal of Eurhizococcus brasiliensis (Wille) (ground pearl), a root mealybug that can lead to economic losses. In this study, the ant communities in vineyards that were infested or uninfested with ground pearls were evaluated in the primary municipalities that produce the Niágara Rosada variety of grapes in southeastern Brazil. The hypothesis of this study was that the composition of the ant community differs between vineyards with and without E. brasiliensis. The ants were collected using subterranean traps in 10 vineyards infested with this mealybug and 10 uninfested vineyards. There was no significant association between ground pearls and the composition or richness of the ant species. Solenopsis invicta (Buren) (Hymenoptera: Formicidae) was the most frequently observed, and Pheidole aberrans (Mayr), Pheidole subarmata (Mayr), and Brachymyrmex incisus F. were common, especially in the rainy season when ground-pearl nymphs were prevalent in the state of São Paulo. Species from preserved or specialized environments were recorded in the vineyards, even with the use of conventional management techniques. PMID:25347833

Munhae, Catarina De Bortoli; Morini, Maria Santina De Castro; Bueno, Odair Correa

2014-01-01

293

Macrophage activation-mediated hydrogen peroxide generation by the royal sun medicinal mushroom Agaricus brasiliensis (Higher Basidiomycetes).  

PubMed

Agaricus brasiliensis has been demonstrated to have potent antitumor activity. The activity is postulated to act through mediation of the host immune system. We have reported that A. brasiliensis extract (ABE) inhibited compound 48/80 induced a systemic anaphylaxis-like reaction, ear swelling response, and passive cutaneous anaphylaxis-like reaction in mice. There is some recent information available on the mechanism of antiallergic effects resulting from oral administration of ABE. However, information regarding how ABE may activate macrophages through intestinal epithelial cells is still limited. To clarify the mechanism of macrophages activation by ABE, a gut in vitro model constructed of Caco-2 and RAW264.7 cells was applied. Treatment of ABE to the apical compartment resulted in significant increases in tumor necrosis factor (TNF)-? production in the basolateral compartment. Moreover, addition of catalase to the basolateral compartment before ABE treatment suppressed TNF-? production completely, but the addition of superoxide dismutase did not suppress this at all. These data suggest that ABE could potentiate hydrogen peroxide emissions from Caco-2 cells into the basolateral side and activate macrophages, which is important in the immune system. PMID:23796218

Mizuno, Masashi; Nishitani, Yosuke

2013-01-01

294

Behavioural evidence of male volatile pheromones in the sex-role reversed wolf spiders Allocosa brasiliensis and Allocosa alticeps  

NASA Astrophysics Data System (ADS)

The use of chemical signals in a sexual context is widespread in the animal kingdom. Most studies in spiders report the use of female pheromones that attract potential sexual partners. Allocosa brasiliensis and Allocosa alticeps are two burrowing wolf spiders that show sex-role reversal. Females locate male burrows and initiate courtship before males perform any detectable visual or vibratory signal. So, females of these species would be detecting chemical or mechanical cues left by males. Our objective was to explore the potential for male pheromones to play a role in mate detection in A. brasiliensis and A. alticeps. We designed two experiments. In Experiment 1, we tested the occurrence of male contact pheromones by evaluating female courtship when exposed to empty burrows constructed by males or females (control). In Experiment 2, we tested the existence of male volatile pheromones by evaluating female behaviour when exposed to artificial burrows connected to tubes containing males, females or empty tubes (control). Our results suggest the occurrence of male volatile pheromones that trigger female courtship in both Allocosa species. The sex-role reversal postulated for these wolf spiders could be driving the consequent reversal in typical pheromone-emitter and detector roles expected for spiders.

Aisenberg, Anita; Baruffaldi, Luciana; González, Macarena

2010-01-01

295

Dentary Morphological Variation in Clevosaurus brasiliensis (Rhynchocephalia, Clevosauridae) from the Upper Triassic of Rio Grande do Sul, Brazil.  

PubMed

Clevosaurus was a cosmopolitan rhynchocephalian genus, known from the Late Triassic to the Early Jurassic. In South America this genus is represented by C. brasiliensis, an important component of the Linha São Luiz taphocoenosis, on the top of the Norian Santa Maria 2 Sequence of Southern Brazil. The best preserved and most abundant bone elements of C. brasiliensis are dentaries, in which variations of shape and size are observed. The aim of this study is to describe and evaluate the variation, using geometric morphometrics methods. Geometric morphometric analysis of 10 specimens highlights variations in relative size of the dentary. Most of the variation observed for PC1 (83.3%) is likely related to ontogeny, and PC2 (10.0%) is likely related to taphonomic signatures. The development patterns observed, such as the growth of the dentary, consists of differential growth in length between the posterior portion of the dentary, that grows at a higher rate, regarding the anterior portion of the element. This allometric growth is similar to what is observed in other rhynchocephalians and is accompanied by the allometric skull growth, similar to the trend exhibited by clevosaurs. The taphocoenosis is bimodal (juveniles and adults) with a bias towards adult preservation. Some diagenetic influence is reflected in deformed skulls and this is observed in the tangent-plot. Finally, a strong correlation was detected between the taphonomic signatures and the PC2, regarding specially disarticulation and degree of fragmentation. PMID:25793754

Romo de Vivar Martínez, Paula Rosario; Bento Soares, Marina

2015-01-01

296

Dentary Morphological Variation in Clevosaurus brasiliensis (Rhynchocephalia, Clevosauridae) from the Upper Triassic of Rio Grande do Sul, Brazil  

PubMed Central

Clevosaurus was a cosmopolitan rhynchocephalian genus, known from the Late Triassic to the Early Jurassic. In South America this genus is represented by C. brasiliensis, an important component of the Linha São Luiz taphocoenosis, on the top of the Norian Santa Maria 2 Sequence of Southern Brazil. The best preserved and most abundant bone elements of C. brasiliensis are dentaries, in which variations of shape and size are observed. The aim of this study is to describe and evaluate the variation, using geometric morphometrics methods. Geometric morphometric analysis of 10 specimens highlights variations in relative size of the dentary. Most of the variation observed for PC1 (83.3%) is likely related to ontogeny, and PC2 (10.0%) is likely related to taphonomic signatures. The development patterns observed, such as the growth of the dentary, consists of differential growth in length between the posterior portion of the dentary, that grows at a higher rate, regarding the anterior portion of the element. This allometric growth is similar to what is observed in other rhynchocephalians and is accompanied by the allometric skull growth, similar to the trend exhibited by clevosaurs. The taphocoenosis is bimodal (juveniles and adults) with a bias towards adult preservation. Some diagenetic influence is reflected in deformed skulls and this is observed in the tangent-plot. Finally, a strong correlation was detected between the taphonomic signatures and the PC2, regarding specially disarticulation and degree of fragmentation. PMID:25793754

Romo de Vivar Martínez, Paula Rosario; Bento Soares, Marina

2015-01-01

297

Characterisation of a Marine Bacterium Vibrio Brasiliensis T33 Producing N-acyl Homoserine Lactone Quorum Sensing Molecules  

PubMed Central

N-acylhomoserine lactones (AHL) plays roles as signal molecules in quorum sensing (QS) in most Gram-negative bacteria. QS regulates various physiological activities in relation with population density and concentration of signal molecules. With the aim of isolating marine water-borne bacteria that possess QS properties, we report here the preliminary screening of marine bacteria for AHL production using Chromobacterium violaceum CV026 as the AHL biosensor. Strain T33 was isolated based on preliminary AHL screening and further identified by using 16S rDNA sequence analysis as a member of the genus Vibrio closely related to Vibrio brasiliensis. The isolated Vibrio sp. strain T33 was confirmed to produce N-hexanoyl-l-homoserine lactone (C6-HSL) and N-(3-oxodecanoyl)-l-homoserine lactone (3-oxo-C10 HSL) through high resolution tandem mass spectrometry analysis. We demonstrated that this isolate formed biofilms which could be inhibited by catechin. To the best of our knowledge, this is the first report that documents the production of these AHLs by Vibrio brasiliensis strain T33. PMID:25006994

Tan, Wen-Si; Yunos, Nina Yusrina Muhamad; Tan, Pui-Wan; Mohamad, Nur Izzati; Adrian, Tan-Guan-Sheng; Yin, Wai-Fong; Chan, Kok-Gan

2014-01-01

298

Effect of the addition of nitrogen sources to cassava fiber and carbon-to-nitrogen ratios on Agaricus brasiliensis growth.  

PubMed

The same substratum formulation to grow Agaricus bisporus has been used to grow Agaricus brasiliensis since its culture started in Brazil. Despite being different species, many of the same rules have been used for composting or axenic cultivation when it comes to nitrogen content and source in the substrate. The aim of this study was to verify the mycelial growth of A. brasiliensis in different ammonium sulfate and (or) urea concentrations added to cassava fiber and different carbon-to-nitrogen (C:N) ratios to increase the efficiency of axenic cultivation. Two nitrogen sources (urea and (or) ammonium sulfate) added to cassava fiber were tested for the in vitro mycelial growth in different C:N ratios (ranging from 2.5:l to 50:l) in the dark at 28 degrees C. The radial mycelial growth was measured after 8 days of growth and recorded photographically at the end of the experiment. Nitrogen from urea enhanced fungal growth better than ammonium sulfate or any mixture of nitrogen. The best C:N ratios for fungal growth were from 10:l to 50:l; C:N ratios below 10:l inhibited fungal growth. PMID:17496959

Mantovani, T R D; Linde, G A; Colauto, N B

2007-01-01

299

Anti-inflammatory activity of Dasyphyllum brasiliensis (Asteraceae) on acute peritonitis induced by beta-glucan from Histoplasma capsulatum.  

PubMed

The tea prepared from leaves and thorns of Dasyphyllum brasiliensis (Asteraceae) is used in the traditional medicine in Brazil for the treatment of oral and oropharyngeal diseases. In this study, we investigated the anti-inflammatory activity of this plant. The aqueous crude extract (ACE), the methanol-water (MeOH-H(2)O) fraction obtained by solvent partition and its fractionation products were evaluated for their anti-inflammatory activities on acute peritonitis induced by beta-glucan from the cell walls of Histoplasma capsulatum. The antiedematogenic activity was also tested using the carrageenan-induced paw edema assay in mice. Oral administration of 100 and 300mg/kg of the ACE in mice caused a significant reduction of neutrophil and eosinophil recruitment in the acute peritonitis assay. In addition, ACE at 300mg/kg inhibited the number of mononuclear cells recruitment. The MeOH-H(2)O fraction and its fractionation products (all at 100mg/kg) also presented anti-inflammatory activities, confirmed by the inhibition of cells recruited to the peritoneal cavity. ACE at 100mg/kg did not show any significant reduction of the edema in the mice paw injected with carrageenan. These data together suggest that Dasyphyllum brasiliensis presents significant anti-inflammatory activity, thus supporting the popular use of the tea in the treatment of inflammatory diseases. PMID:17475425

Castelucci, Simone; de Paula Rogerio, Alexandre; Ambrosio, Sérgio Ricardo; Arakawa, Nilton Syogo; de Lira, Simone Possedente; Faccioli, Lúcia Helena; Da Costa, Fernando Batista

2007-05-30

300

Yeast flora of grape berries during ripening  

Microsoft Academic Search

The yeast flora associated with the surface of grapes during ripening was studied with regard to different sectors of the grape skin and the position in the bunch by means of traditional as well as more vigorous preisolation and precounting treatments. The yeast number per square centimeter of skin increases with ripening and is highest in the area immediately surrounding

Gianfranco Rosini; Federico Federici; Alessandro Martini

1982-01-01

301

Chronological aging leads to apoptosis in yeast  

Microsoft Academic Search

uring the past years, yeast has been successfully established as a model to study mechanisms of apoptotic regulation. However, the beneficial effects of such a cell suicide program for a unicellular organism remained obscure. Here, we demonstrate that chronologi- cally aged yeast cultures die exhibiting typical markers of apoptosis, accumulate oxygen radicals, and show caspase activation. Age-induced cell death is

Eva Herker; Helmut Jungwirth; Katharina A. Lehmann; Corinna Maldener; Kai-Uwe Fröhlich; Silke Wissing; Sabrina Büttner; Markus Fehr; Stephan Sigrist; Frank Madeo

2004-01-01

302

Production of recombinant proteins by yeast cells  

Microsoft Academic Search

Yeasts are widely used in production of recombinant proteins of medical or industrial interest. For each individual product, the most suitable expression system has to be identified and optimized, both on the genetic and fermentative level, by taking into account the properties of the product, the organism and the expression cassette. There is a wide range of important yeast expression

Eda Çelik; P?nar Çal?k

303

Growth of yeasts during wine fermentations  

Microsoft Academic Search

This article emphasises the importance of making quantitative measurements of the growth of yeast species during wine fermentations. Although such studies confirm Saccharomyces cerevisiae as the principal wine yeast, they show that indigenous species of Kloeckera and Candida make a more significant contribution to the fermentation than previously thought. Inoculation of grape juice with S. cerevisiae does not necessarily suppress

Graham H. Fleet

1990-01-01

304

Fermentation studies using Saccharomyces diastaticus yeast strains  

SciTech Connect

The yeast species, Saccharomyces diastaticus, has the ability to ferment starch and dextrin, because of the extracellular enzyme, glucoamylase, which hydrolyzes the starch/dextrin to glucose. A number of nonallelic genes--DEX 1, DEX 2, and dextrinase B which is allelic to STA 3--have been isolated, which impart to the yeast the ability to ferment dextrin. Various diploid yeast strains were constructed, each being either heterozygous or homozygous for the individual dextrinase genes. Using 12 (sup 0) plato hopped wort (30% corn adjunct) under agitated conditions, the fermentation rates of the various diploid yeast strains were monitored. A gene-dosage effect was exhibited by yeast strains containing DEX 1 or DEX 2, however, not with yeast strains containing dextrinase B (STA 3). The fermentation and growth rates and extents were determined under static conditions at 14.4 C and 21 C. With all yeast strains containing the dextrinase genes, both fermentation and growth were increased at the higher incubation temperature. Using 30-liter fermentors, beer was produced with the various yeast strains containing the dextrinase genes and the physical and organoleptic characteristics of the products were determined. The concentration of glucose in the beer was found to increase during a 3-mo storage period at 21 C, indicating that the glucoamylase from Saccharomyces diastaticus is not inactivated by pasteurization. (Refs. 36).

Erratt, J.A.; Stewart, G.G.

1981-01-01

305

Rapid and reliable protein extraction from yeast  

Microsoft Academic Search

The methods currently used for protein extraction from yeast are either laborious or insufficiently reliable. Here I report a method for protein extraction for electrophoretic analysis that is both easy and reliable. In this method, yeast cells are subjected to mild alkali treatment and then boiled in a standard electrophoresis loading buffer. The method was tested for different strains of

Vitaly V. Kushnirov

2000-01-01

306

YEAST MEIOSIS Sister kinetochores are mechanically  

E-print Network

YEAST MEIOSIS Sister kinetochores are mechanically fused during meiosis I in yeast Krishna K Production of healthy gametes requires a reductional meiosis I division in which replicated sister chromatids comigrate, rather than separate as in mitosis or meiosis II. Fusion of sister kinetochores during meiosis I

Asbury, Chip

307

The wine and beer yeast Dekkera bruxellensis  

PubMed Central

Recently, the non-conventional yeast Dekkera bruxellensis has been gaining more and more attention in the food industry and academic research. This yeast species is a distant relative of Saccharomyces cerevisiae and is especially known for two important characteristics: on the one hand, it is considered to be one of the main spoilage organisms in the wine and bioethanol industry; on the other hand, it is 'indispensable' as a contributor to the flavour profile of Belgium lambic and gueuze beers. Additionally, it adds to the characteristic aromatic properties of some red wines. Recently this yeast has also become a model for the study of yeast evolution. In this review we focus on the recently developed molecular and genetic tools, such as complete genome sequencing and transformation, to study and manipulate this yeast. We also focus on the areas that are particularly well explored in this yeast, such as the synthesis of off-flavours, yeast detection methods, carbon metabolism and evolutionary history. © 2014 The Authors. Yeast published by John Wiley & Sons, Ltd. PMID:24932634

Schifferdecker, Anna Judith; Dashko, Sofia; Ishchuk, Olena P; Piškur, Jure

2014-01-01

308

Yeasts are essential for cocoa bean fermentation.  

PubMed

Cocoa beans (Theobroma cacao) are the major raw material for chocolate production and fermentation of the beans is essential for the development of chocolate flavor precursors. In this study, a novel approach was used to determine the role of yeasts in cocoa fermentation and their contribution to chocolate quality. Cocoa bean fermentations were conducted with the addition of 200ppm Natamycin to inhibit the growth of yeasts, and the resultant microbial ecology and metabolism, bean chemistry and chocolate quality were compared with those of normal (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii and Kluyveromyces marxianus, the lactic acid bacteria Lactobacillus plantarum and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in the control fermentation. In fermentations with the presence of Natamycin, the same bacterial species grew but yeast growth was inhibited. Physical and chemical analyses showed that beans fermented without yeasts had increased shell content, lower production of ethanol, higher alcohols and esters throughout fermentation and lesser presence of pyrazines in the roasted product. Quality tests revealed that beans fermented without yeasts were purplish-violet in color and not fully brown, and chocolate prepared from these beans tasted more acid and lacked characteristic chocolate flavor. Beans fermented with yeast growth were fully brown in color and gave chocolate with typical characters which were clearly preferred by sensory panels. Our findings demonstrate that yeast growth and activity were essential for cocoa bean fermentation and the development of chocolate characteristics. PMID:24462702

Ho, Van Thi Thuy; Zhao, Jian; Fleet, Graham

2014-03-17

309

Yeast: An Experimental Organism for Modern Biology.  

ERIC Educational Resources Information Center

Discusses the applicability and advantages of using yeasts as popular and ideal model systems for studying and understanding eukaryotic biology at the cellular and molecular levels. Cites experimental tractability and the cooperative tradition of the research community of yeast biologists as reasons for this success. (RT)

Botstein, David; Fink, Gerald R.

1988-01-01

310

Whole-Transcriptome Survey of the Putative ATP-Binding Cassette (ABC) Transporter Family Genes in the Latex-Producing Laticifers of Hevea brasiliensis.  

PubMed

The ATP-binding cassette (ABC) proteins or transporters constitute a large protein family in plants and are involved in many different cellular functions and processes, including solute transportation, channel regulation and molecular switches, etc. Through transcriptome sequencing, a transcriptome-wide survey and expression analysis of the ABC protein genes were carried out using the laticiferous latex from Hevea brasiliensis (rubber tree). A total of 46 putative ABC family proteins were identified in the H. brasiliensis latex. These consisted of 12 'full-size', 21 'half-size' and 13 other putative ABC proteins, and all of them showed strong conservation with their Arabidopsis thaliana counterparts. This study indicated that all eight plant ABC protein paralog subfamilies were identified in the H. brasiliensis latex, of which ABCB, ABCG and ABCI were the most abundant. Real-time quantitative reverse transcription-polymerase chain reaction assays demonstrated that gene expression of several latex ABC proteins was regulated by ethylene, jasmonic acid or bark tapping (a wound stress) stimulation, and that HbABCB15, HbABCB19, HbABCD1 and HbABCG21 responded most significantly of all to the abiotic stresses. The identification and expression analysis of the latex ABC family proteins could facilitate further investigation into their physiological involvement in latex metabolism and rubber biosynthesis by H. brasiliensis. PMID:25615936

Zhiyi, Nie; Guijuan, Kang; Yu, Li; Longjun, Dai; Rizhong, Zeng

2015-01-01

311

Whole-Transcriptome Survey of the Putative ATP-Binding Cassette (ABC) Transporter Family Genes in the Latex-Producing Laticifers of Hevea brasiliensis  

PubMed Central

The ATP-binding cassette (ABC) proteins or transporters constitute a large protein family in plants and are involved in many different cellular functions and processes, including solute transportation, channel regulation and molecular switches, etc. Through transcriptome sequencing, a transcriptome-wide survey and expression analysis of the ABC protein genes were carried out using the laticiferous latex from Hevea brasiliensis (rubber tree). A total of 46 putative ABC family proteins were identified in the H. brasiliensis latex. These consisted of 12 ‘full-size’, 21 ‘half-size’ and 13 other putative ABC proteins, and all of them showed strong conservation with their Arabidopsis thaliana counterparts. This study indicated that all eight plant ABC protein paralog subfamilies were identified in the H. brasiliensis latex, of which ABCB, ABCG and ABCI were the most abundant. Real-time quantitative reverse transcription-polymerase chain reaction assays demonstrated that gene expression of several latex ABC proteins was regulated by ethylene, jasmonic acid or bark tapping (a wound stress) stimulation, and that HbABCB15, HbABCB19, HbABCD1 and HbABCG21 responded most significantly of all to the abiotic stresses. The identification and expression analysis of the latex ABC family proteins could facilitate further investigation into their physiological involvement in latex metabolism and rubber biosynthesis by H. brasiliensis. PMID:25615936

Zhiyi, Nie; Guijuan, Kang; Yu, Li; Longjun, Dai; Rizhong, Zeng

2015-01-01

312

EXTRALIMITAL RECORDS OF THE MEXICAN FREE-TAILED BAT (TADARIDA BRASILIENSIS MEXICANA) IN THE CENTRAL UNITED STATES AND THEIR BIOLOGICAL SIGNIFICANCE  

Microsoft Academic Search

Two new records of Tadarida brasiliensis mexicana are reported from Nebraska. The literature records of this taxon from the central United States are summarized. In this region of North America, these bats occupy a “natal range” where the species carries on regular reproductive activities and the populations are relatively stable, including California, Arizona, New Mexico, Texas, and Oklahoma. To the

Hugh H. Genoways; Patricia W. Freeman; Cary Grell

2000-01-01

313

Yeasts that utilize lactose in sweet whey  

SciTech Connect

Since processing costs are usually higher for whey than for other available food or feed nutrients, only about one-third of whey produced in the US is used by food and feed industries. As a result whey disposal costs are a problem. Further; when whey is disposed of through municipal sewerage systems, the lactose present is changed by bacteria to lactic acid which tends to act as a preservative and retards further oxidation of whey constituents. This article describes a method of utilizing lactose-fermenting yeasts to produce large quantities of yeast cells, single-cell protein. Kluveromyces fragilis was found to be the most effective yeast species and the yeast cells produced could be used as a natural food or feed additive. Results of this study determined that certain methods and yeast strains could reduce whey-related pollution and thus help reduce costs of whey disposal.

Gholson, J.H.; Gough, R.H.

1980-01-01

314

Production of ethanol by immobilized yeast cells  

SciTech Connect

Saccharomyces cerevisiae cells were immobilized in calcium alginate beads for use in the continuous production of ethanol. Yeasts were grown in medium supplemented with ethanol to selectively screen for a culture which showed the greatest tolerance to ethanol inhibition. Yeast beads were produced from a yeast slurry containing 1.5% alginate (w/v) which was added as drops to a 0.05M CaCl2 solution. To determine their optimum fermentation parameters, ethanol production using glucose as a substrate was monitored in batch systems at varying physiological conditions (temperature,pH, ethanol concentration), cell densities, and gel concentrations. The data obtained were compared to optimum free cell ethanol fermentation parameters. The immobilized yeast cells were examined in a packed-bed reactor system operated under optimized parameters derived from batch-immobilized yeast cell experiments. Ethanol production rates, as well as residual sugar concentrations were monitored at different feedstock flow rates. (Refs. 13).

Williams, D.; Munnecke, D.M.

1981-08-01

315

Polysaccharides from Agaricus bisporus and Agaricus brasiliensis show similarities in their structures and their immunomodulatory effects on human monocytic THP-1 cells  

PubMed Central

Background Mushroom polysaccharides have traditionally been used for the prevention and treatment of a multitude of disorders like infectious illnesses, cancers and various autoimmune diseases. Crude mushroom extracts have been tested without detailed chemical analyses of its polysaccharide content. For the present study we decided to chemically determine the carbohydrate composition of semi-purified extracts from 2 closely related and well known basidiomycete species, i.e. Agaricus bisporus and A. brasiliensis and to study their effects on the innate immune system, in particular on the in vitro induction of pro-inflammatory cytokines, using THP-1 cells. Methods Mushroom polysaccharide extracts were prepared by hot water extraction and precipitation with ethanol. Their composition was analyzed by GC-MS and NMR spectroscopy. PMA activated THP-1 cells were treated with the extracts under different conditions and the production of pro-inflammatory cytokines was evaluated by qPCR. Results Semi-purified polysaccharide extracts of A. bisporus and A. brasiliensis (= blazei) were found to contain (1?6),(1?4)-linked ?-glucan, (1?6)-linked ?-glucan, and mannogalactan. Their proportions were determined by integration of 1H-NMR signs, and were considerably different for the two species. A. brasiliensis showed a higher content of ?-glucan, while A. bisporus presented mannogalactan as its main polysaccharide. The extracts induced a comparable increase of transcription of the pro-inflammatory cytokine genes IL-1? and TNF-? as well as of COX-2 in PMA differentiated THP-1 cells. Pro-inflammatory effects of bacterial LPS in this assay could be reduced significantly by the simultaneous addition of A. brasiliensis extract. Conclusions The polysaccharide preparations from the closely related species A. bisporus and A. brasiliensis show major differences in composition: A. bisporus shows high mannogalactan content whereas A. brasiliensis has mostly ?-glucan. Semi-purified polysaccharide extracts from both Agaricus species stimulated the production of pro-inflammatory cytokines and enzymes, while the polysaccharide extract of A. brasiliensis reduced synthesis of these cytokines induced by LPS, suggesting programmable immunomodulation. PMID:21787425

2011-01-01

316

Nucleotide excision repair in yeast.  

PubMed

In nucleotide excision repair (NER) in eukaryotes, DNA is incised on both sides of the lesion, resulting in the removal of a fragment approximately 25-30 nucleotides long. This is followed by repair synthesis and ligation. The proteins encoded by the various yeast NER genes have been purified, and the incision reaction reconstituted in vitro. This reaction requires the damage binding factors Rad14, RPA, and the Rad4-Rad23 complex, the transcription factor TFIIH which contains the two DNA helicases Rad3 and Rad25, essential for creating a bubble structure, and the two endonucleases, the Rad1-Rad10 complex and Rad2, which incise the damaged DNA strand on the 5'- and 3'-side of the lesion, respectively. Addition of the Rad7-Rad16 complex to this reconstituted system stimulates the incision reaction many fold. The various NER proteins exist in vivo as part of multiprotein subassemblies which have been named NEFs (nucleotide excision repair factors). Rad14 and Rad1-Rad10 form one subassembly called NEF1, the Rad4-Rad23 complex is named NEF2, Rad2 and TFIIH constitute NEF3, and the Rad7-Rad16 complex is called NEF4. Although much has been learned from yeast about the function of NER genes and proteins in eukaryotes, the underlying mechanisms by which damage is recognized, NEFs are assembled at the damage site, and the DNA is unwound and incised, remain to be elucidated. PMID:10915862

Prakash, S; Prakash, L

2000-06-30

317

Regulation of yeast oscillatory dynamics  

PubMed Central

When yeast cells are grown continuously at high cell density, a respiratory oscillation percolates throughout the population. Many essential cellular functions have been shown to be separated temporally during each cycle; however, the regulatory mechanisms involved in oscillatory dynamics remain to be elucidated. Through GC-MS analysis we found that the majority of metabolites show oscillatory dynamics, with 70% of the identified metabolite concentrations peaking in conjunction with NAD(P)H. Through statistical analyses of microarray data, we identified that biosynthetic events have a defined order, and this program is initiated when respiration rates are increasing. We then combined metabolic, transcriptional data and statistical analyses of transcription factor activity, identified the top oscillatory parameters, and filtered a large-scale yeast interaction network according to these parameters. The analyses and controlled experimental perturbation provided evidence that a transcriptional complex formed part of the timing circuit for biosynthetic, reductive, and cell cycle programs in the cell. This circuitry does not act in isolation because both have strong translational, proteomic, and metabolic regulatory mechanisms. Our data lead us to conclude that the regulation of the respiratory oscillation revolves around coupled subgraphs containing large numbers of proteins and metabolites, with a potential to oscillate, and no definable hierarchy, i.e., heterarchical control. PMID:17284613

Murray, Douglas B.; Beckmann, Manfred; Kitano, Hiroaki

2007-01-01

318

Natural and Vaccine-Mediated Immunity to Salmonella Typhimurium is Impaired by the Helminth Nippostrongylus brasiliensis  

PubMed Central

Background The impact of exposure to multiple pathogens concurrently or consecutively on immune function is unclear. Here, immune responses induced by combinations of the bacterium Salmonella Typhimurium (STm) and the helminth Nippostrongylus brasiliensis (Nb), which causes a murine hookworm infection and an experimental porin protein vaccine against STm, were examined. Methodology/Principal Findings Mice infected with both STm and Nb induced similar numbers of Th1 and Th2 lymphocytes compared with singly infected mice, as determined by flow cytometry, although lower levels of secreted Th2, but not Th1 cytokines were detected by ELISA after re-stimulation of splenocytes. Furthermore, the density of FoxP3+ T cells in the T zone of co-infected mice was lower compared to mice that only received Nb, but was greater than those that received STm. This reflected the intermediate levels of IL-10 detected from splenocytes. Co-infection compromised clearance of both pathogens, with worms still detectable in mice weeks after they were cleared in the control group. Despite altered control of bacterial and helminth colonization in co-infected mice, robust extrafollicular Th1 and Th2-reflecting immunoglobulin-switching profiles were detected, with IgG2a, IgG1 and IgE plasma cells all detected in parallel. Whilst extrafollicular antibody responses were maintained in the first weeks after co-infection, the GC response was less than that in mice infected with Nb only. Nb infection resulted in some abrogation of the longer-term development of anti-STm IgG responses. This suggested that prior Nb infection may modulate the induction of protective antibody responses to vaccination. To assess this we immunized mice with porins, which confer protection in an antibody-dependent manner, before challenging with STm. Mice that had resolved a Nb infection prior to immunization induced less anti-porin IgG and had compromised protection against infection. Conclusion These findings demonstrate that co-infection can radically alter the development of protective immunity during natural infection and in response to immunization. PMID:25474738

Bobat, Saeeda; Darby, Matthew; Mrdjen, Dunja; Cook, Charlotte; Logan, Erin; Auret, Jennifer; Jones, Elizabeth; Schnoeller, Corinna; Flores-Langarica, Adriana; Ross, Ewan A.; Vira, Alykhan; López-Macías, Constantino; Henderson, Ian R.; Alexander, James; Brombacher, Frank; Horsnell, William G.; Cunningham, Adam F.

2014-01-01

319

A Caspase-Related Protease Regulates Apoptosis in Yeast  

Microsoft Academic Search

Yeast can undergo cell death accompanied by cellular markers of apoptosis. However, orthologs of classical mammalian apoptosis regulators appeared to be missing from the yeast genome, challenging a common mechanism of yeast and mammalian apoptosis. Here we investigate Yor197w, a yeast protein with structural homology to mammalian caspases, and demonstrate caspase-like processing of the protein. Hydrogen peroxide treatment induces apoptosis

Frank Madeo; Eva Herker; Corinna Maldener; Silke Wissing; Stephan Lächelt; Mark Herlan; Markus Fehr; Kirsten Lauber; Stephan J Sigrist; Sebastian Wesselborg; Kai-Uwe Fröhlich

2002-01-01

320

Original article Effect of a viable yeast culture on digestibility  

E-print Network

Original article Effect of a viable yeast culture on digestibility and rumen fermentation in sheep that the effect of yeast culture on ru- men fermentation may depend on the nature of.the diet. Living yeast cell survived the passage through the digestive tract. yeast I rumen fermentation I volatile fatty acids I sheep

Boyer, Edmond

321

The genetics of aging in the yeast Saccharomyces cerevisiae  

Microsoft Academic Search

The yeastSaccharomyces cerevisiae possesses a finite life span similar in many attributes and implications to that of higher eukaryotes. Here, the measure of the life span is the number of generations or divisions the yeast cell has undergone. The yeast cell is the organism, simplifying many aspects of aging research. Most importantly, the genetics of yeast is highly-developed and readily

S. Michal Jazwinski

1993-01-01

322

[Effects of nitrogen on performance and yeast morphology of yeast-SBR system].  

PubMed

Effects of nitrogen on yeast cell morphology, settleability and performance of wastewater treatment were investigated in treating oil-containing wastewater by yeast-SBR system. The results show that: nitrogen supply affects directly yeast biomass, settleability, pH and treatment efficiency of system; the absence of nitrogen induces the transformation of certain yeast cells from single cell to hypha morphology. Based on an overall consideration of efficiency and stability of yeast-SBR system, the optimum BOD/N ratio of influent is 20/1. The optimum nitrogen supply can improve wastewater treatment efficiency of systems with different degrees of nitrogen absence and make yeast morphology become the predominant morphology for slightly mycelial system over a short time, but for severe mycelial system, the hypha morphology still keeps dominant. PMID:18624205

Lü, Wen-Zhou; Liu, Ying; Chen, He-Ping; Zhu, Jian-Lin

2008-05-01

323

MAP kinase dynamics in yeast.  

PubMed

MAP kinase pathways play key roles in cellular responses towards extracellular signals. In several cases, the three core kinases interact with a scaffold molecule, but the function of these scaffolds is poorly understood. They have been proposed to contribute to signal specificity, signal amplification, or subcellular localization of MAP kinases. Several MAP kinases translocate to the nucleus in response to their activation, suggesting that nuclear transport may provide a regulatory mechanism. Here we describe new applications for Fluorescence Recovery After Photobleaching (FRAP) and Fluorescence Loss In Photobleaching (FLIP), to study dynamic translocations of MAPKs between different subcellular compartments. We have used these methods to measure the nuclear/cytoplasmic dynamics of several yeast MAP kinases, and in particular to address the role of scaffold proteins for MAP-kinase signaling. PMID:11730324

van Drogen, F; Peter, M

2001-09-01

324

Corning and Kroger turn whey to yeast  

SciTech Connect

It is reported that Corning and Kroger intend to build a 35,000 sq. ft. plant in Winchester, Ky., that will turn whey into bakers' yeast. The plant will convert whey from Kroger's dairies into bakers' yeast, supplying about 60% of the yeast needed for nine Kroger bakeries. It will also produce syrups and whey protein concentrate for use in other food processing activities. In addition to making useful products, the project will convert the whey to glucose and galactose. The protein component of the whey will be concentrated and used in various foods and feeds.

Not Available

1981-11-16

325

Yeast molecular biology recombinant DNA. Recent advances  

SciTech Connect

Insights into recombinant DNA technology, as applied to yeast research, are described in this volume based on the First Berkeley Workshop on Recent Advances in Yeast Molecular Biology. The results of various genetic engineering techniques in recombinant DNA studies in yeast are detailed and discussed. The papers describe experimental approaches using the newest technologies of DNA transformations, molecular cloning, and DNA sequence analysis. These techniques are employed to gain new information regarding chromosomal structure, gene regulation, DNA recombination and repair, and cell type control.

Esposito, M.S.

1984-01-01

326

Yeast culture volatiles as attractants for Rhodnius prolixus: electroantennogram responses and captures in yeast-baited traps  

Microsoft Academic Search

Responses to air currents carrying volatiles from yeast cultures were measured by means of electroantennograms (EAGs) in the haematophagous bug Rhodnius prolixus and we tested yeast-baited traps in the laboratory. The volatiles liberated by yeast cultures generated a clear electrophysiological response, much higher than that obtained during stimulation with clean air. The addition of yeast cultures to the traps dramatically

M. G. Lorenzo; G. Manrique; H. H. R. Pires; M. G. de Brito Sánchez; L. Diotaiuti; C. R. Lazzari

1999-01-01

327

YeastWeb: a workset-centric web resource for gene family analysis in yeast  

PubMed Central

Background Currently, a number of yeast genomes with different physiological features have been sequenced and annotated, which provides invaluable information to investigate yeast genetics, evolutionary mechanism, structure and function of gene families. Description YeastWeb is a novel database created to provide access to gene families derived from the available yeast genomes by assigning the genes into putative families. It has many useful features that complement existing databases, such as SGD, CYGD and Génolevures: 1) Detailed computational annotation was conducted with each entry with InterProScan, EMBOSS and functional/pathway databases, such as GO, COG and KEGG; 2) A well established user-friendly environment was created to allow users to retrieve the annotated genes and gene families using functional classification browser, keyword search or similarity-based search; 3) Workset offers users many powerful functions to manage the retrieved data efficiently, associate the individual items easily and save the intermediate results conveniently; 4) A series of comparative genomics and molecular evolution analysis tools are neatly implemented to allow users to view multiple sequence alignments and phylogenetic tree of gene families. At present, YeastWeb holds the gene families clustered from various MCL inflation values from a total of 13 available yeast genomes. Conclusions Given the great interest in yeast research, YeastWeb has the potential to become a useful resource for the scientific community of yeast biologists and related researchers investigating the evolutionary relationship of yeast gene families. YeastWeb is available at http://centre.bioinformatics.zj.cn/Yeast/. PMID:20624324

2010-01-01

328

Identification of oversulphated galactosaminoglycans in intestinal-mucosal mast cells of rats infected with the nematode worm Nippostrongylus brasiliensis.  

PubMed Central

The oversulphated galactosaminoglycans synthesized by rat mucosal mast cells were isolated from the small intestine of animals infected with the nematode Nippostrongylus brasiliensis, which causes proliferation of these cells. The 35S-labelled polysaccharides were degraded by digestion with chondroitinase ABC, and the structures of the disaccharide products were determined by cleavage with mercuric acetate followed by electrophoretic characterization of the resultant sulphated monosaccharides. It was concluded that about half of the disulphated disaccharide units in the polysaccharide consisted of chondroitin sulphate E-type structures [GlcA-GalNAc(4,6-di-OSO3)], in which both sulphate groups were located on the N-acetylgalactosamine unit. The remainder consisted of isomeric structures with one sulphate group on the N-acetylgalactosamine residue and one on the hexuronic acid unit and presumably represented the dermatan sulphate-type sequence [IdoA(2-OSO3)-GalNAc(4-OSO3)]. PMID:3178741

Kusche, M; Lindahl, U; Enerbäck, L; Rodén, L

1988-01-01

329

Prion formation by a yeast GLFG nucleoporin  

E-print Network

The self-assembly of proteins into higher order structures is both central to normal biology and a dominant force in disease. Certain glutamine/asparagine (Q/N)-rich proteins in the budding yeast Saccharomyces cerevisiae ...

Halfmann, Randal

330

Monitoring Air Quality with Leaf Yeasts.  

ERIC Educational Resources Information Center

Proposes that leaf yeast serve as quick, inexpensive, and effective techniques for monitoring air quality. Outlines procedures and provides suggestions for data analysis. Includes results from sample school groups who employed this technique. (ML)

Richardson, D. H. S.; And Others

1985-01-01

331

Yeast Genomic DNA Prep Sterile distilled water  

E-print Network

Auble Lab Yeast Genomic DNA Prep Reagents: Sterile distilled water -mercaptoethanol Sorbitol Buffer conical tube at 3,000 rpms for 5 minutes. 3. Resuspend in 10 ml of sterile distilled (SD) water, then spin

Auble, David

332

Comparative Functional Genomics of the Fission Yeasts  

E-print Network

The fission yeast clade—comprising Schizosaccharomyces pombe, S. octosporus, S. cryophilus, and S. japonicus—occupies the basal branch of Ascomycete fungi and is an important model of eukaryote biology. A comparative ...

Regev, Aviv

333

Protection from nitrosative stress by yeast flavohemoglobin  

PubMed Central

Yeast hemoglobin was discovered close to half a century ago, but its function has remained unknown. Herein, we report that this flavohemoglobin protects Saccharomyces cerevisiae from nitrosative stress. Deletion of the flavohemoglobin gene (YHB1) abolished the nitric oxide (NO)-consuming activity of yeast cells. Levels of protein nitrosylation were more than 10-fold higher in yhb1 mutant yeast than in isogenic wild-type cells after incubation with NO donors. Growth of mutant cells was inhibited by a nitrosative challenge that had little effect on wild-type cells, whereas the resistance of mutant cells to oxidative stress was unimpaired. Protection conferred by yeast flavohemoglobin against NO and S-nitrosothiols was seen under both anaerobic and aerobic conditions, consistent with a primary function in NO detoxification. A phylogenetic analysis indicated that protection from nitrosative stress is likely to be a conserved function among microorganismal flavohemoglobins. Flavohemoglobin is therefore a potential target for antimicrobial therapy. PMID:10758168

Liu, Limin; Zeng, Ming; Hausladen, Alfred; Heitman, Joseph; Stamler, Jonathan S.

2000-01-01

334

Macromolecular synthesis by yeasts under frozen conditions  

E-print Network

by the protein synthesis inhibitor cycloheximide. Experi- ments at -5°C under frozen and liquid conditionsMacromolecular synthesis by yeasts under frozen conditions Pierre Amato,* Shawn Doyle and Brent C

Christner, Brent C.

335

Predictive distribution modeling of the sandy-beach supralittoral amphipod Atlantorchestoidea brasiliensis along a macroscale estuarine gradient  

NASA Astrophysics Data System (ADS)

Exposed marine beaches are physically rigorous habitats in which macrofaunal patterns have been well correlated with physical factors. In this context, the habitat safety hypothesis (HSH) predicts an increase in abundance of supralittoral species from dissipative to reflective conditions in microtidal oceanic beaches. However, the HSH has not been adequately tested in estuarine sandy beaches. Here, we build a predictive model based on the supralittoral talitrid amphipod Atlantorchestoidea brasiliensis that allowed us to test the HSH along a macroscale estuarine gradient. Fifteen Uruguayan sandy beaches along a salinity gradient (from 0.1 to 34.3) generated by the Río de la Plata estuary (SW Atlantic Ocean) were sampled over a two-year period. A conditional two-step procedure using a General Additive Model (GAM) was performed in order to model A. brasiliensis occurrence (1st-step) and abundance (2nd-step), based on a comprehensive set of environmental variables [salinity, water temperature, beach face slope (BFS), mean grain size, wave height and sand compaction, moisture and organic matter]. Each GAM was parameterized using generalized linear models (GLMs). An external validation procedure was used. Data were divided randomly into training (75%) and test (25%) sets. The 1st-step GAM/GLM retained 5 physical descriptors in the model (decreasing order of importance): wave height, salinity, BFS, organic matter and sand compaction. The 2nd-step GAM/GLM retained 6 physical descriptors: sand compaction, water content, salinity, wave height, water temperature and organic matter. The predictive ability of these models and the resulted combined model, as well as their external validity, was highly significant and supported the predictions of the HSH. However, the highest and lowest abundances were observed, respectively, on reflective and dissipative beaches in the outer estuary; i.e., the predictions based on the HSH did not account for the high levels of abundance observed on these beaches compared with oceanic ones. Therefore, the HSH was expanded to include microtidal estuarine beaches.

Gómez, Julio; Defeo, Omar

2012-02-01

336

Direct effects of IL-4/IL-13 and the nematode Nippostrongylus brasiliensis on intestinal epithelial cells in vitro.  

PubMed

Nematode infections induce the upregulation of mucin- and glycosylation-related genes in intestinal epithelial cells in vivo. However, the factor(s) that induce these changes in epithelial cells have not been fully elucidated. In the present study, we analysed the effects of the Th2 cytokines IL-4 and IL-13 and the excretory-secretory (ES) product of the nematode Nippostrongylus brasiliensis on the gene expression of the major mucin core peptide MUC2, the sialyltransferase ST3GalIV (Siat4c) and the sulphotransferase HS3ST1 in intestinal epithelium-derived IEC-6 cells by quantitative reverse transcription (RT)-PCR. The administration of IL-4 and IL-13 resulted in a significant upregulation of ST3GalIV and HS3ST1 gene transcription, but had no effect on MUC2, in IEC-6 cells. RT-PCR studies also demonstrated the constitutive expression of IL-13Ralpha1 and IL-4R in IEC-6 cells. On the other hand, the ES product induced upregulation of ST3GalIV, but not HS3ST1 or MUC2, while coadministration of IL-13 and the ES product induced a slight but significant upregulation of MUC2. Co-incubation of live N. brasiliensis adult worms with IEC-6 cells resulted in the upregulation of ST3GalIV and MUC2. These results suggested that HS3ST1 gene expression is strictly regulated by IL-4/IL-13, while ST3GalIV and MUC2 gene expressions are regulated by redundant mechanisms. PMID:20500673

Takeda, K; Hashimoto, K; Uchikawa, R; Tegoshi, T; Yamada, M; Arizono, N

2010-06-01

337

Distribution of 2-[I]iodomelatonin binding in the brain of Mexican free-tailed bats (Tadarida brasiliensis).  

PubMed

The neurohormone melatonin is an important signal for both time of day and time of year in many seasonally breeding animals. High densities of melatonin receptors have been found in the suprachiasmatic nucleus, median eminence, and the pituitary gland in almost all mammals investigated so far, and lower densities of melatonin receptors have also been localized to other brain regions varying in a species-specific fashion. Because species-specific differences in receptor distributions have been correlated with differences in behavior and ecology, a comparative study of how melatonin receptors are distributed in vertebrate brains can be useful to the understanding of the functional organization of neural circuits controlling daily and seasonal behaviors. In this study, we localized and characterized melatonin binding sites in the brain of the Mexican free-tailed bat (Tadarida brasiliensis) using in vitro autoradiography with 2-[(125)I]iodomelatonin. Tadarida brasiliensis is a nocturnal insectivorous mammal that seasonally migrates, reproduces once a year, and exhibits documented sexual dimorphisms in seasonal reproductive behaviors, most notably in courtship vocalizations. Prominent 2-[(125)I]iodomelatonin binding was found in the median eminence, suprachiasmatic nuclei, and hippocampus, similar to that observed in other mammals. High densities of binding were also localized to structures of the basal ganglia, including the caudate nucleus, putamen, and nucleus accumbens, a feature commonly observed in songbirds but not in mammals. Saturation analysis indicated that the observed binding sites had an affinity for melatonin typical of the binding properties for the Mel(1a) receptor subtype. We conclude that melatonin receptor distributions in the Mexican free-tailed bat brain appear to show similarities with the reproductive and circadian systems of other mammals and the basal ganglia of songbirds. PMID:19223684

Schwartz, Christine; Bartell, Paul; Cassone, Vincent; Smotherman, Michael

2009-01-01

338

Featured Organism: Schizosaccharomyces pombe, The Fission Yeast  

PubMed Central

Schizosaccharomyces pombe, the fission yeast, has long been a crucial model for the study of the eukaryote cell cycle. We take a look at this important yeast, whose genome has recently been completed, featuring comments from Valerie Wood, Jürg Bähler, Ramsay McFarlane, Susan Forsburg, Iain Hagan and Paul Nurse on the implications of having the complete sequence and future prospects for pombe genomics. PMID:18628834

2002-01-01

339

Whey Alcohol Fermentation with Mixed Yeast Cultures  

Microsoft Academic Search

This paper study the process of whey alcohol fermentation with mixed yeasts cultures. After the experiments of strains combination, the yeast strains of Saccharomyces uvarum TY-3, Saccharomyces uvarum TY-1 and Saccharomyces carlsbergensis AY-5 were selected and mixed at the ratio of 5.0:2.5:2.5. The optimized fermenting condition was obtained through orthogonal experiments with the result as follows: the initial pH value

Wang Jianming; Guo Linhai; Zhao Guoren

2009-01-01

340

Mitochondria, metabolism, and aging in yeast  

Microsoft Academic Search

\\u000a Quantitative and qualitative changes in metabolism take place when the lifespan is extended in yeast either by genetic or\\u000a nutritional manipulation. In particular, remodeling of mitochondrial function occurs, and the relationship between this organelle\\u000a and other cellular compartments moves to the fore. Two separate pathways, the retrograde response and calorie restriction,\\u000a operate as metabolic mechanisms for life extension in yeast.

S. Michal Jazwinski

341

How to Make Yeast Cells Thrive  

NSDL National Science Digital Library

Students set up and run the experiments they designed in the Population Growth in Yeasts associated lesson, using simple yeast-molasses cultures in test tubes. Population growth is indicated by the amount of respiration occurring in the cultures, which in turn is indicated by the growth of carbon dioxide bubbles trapped within the culture tubes. Using this method, students test for a variety of environmental influences, such as temperature, food supply and pH.

2014-09-18

342

Yeast communities in a natural tequila fermentation.  

PubMed

Fresh and cooked agave, Drosophila spp., processing equipment, agave molasses, agave extract, and fermenting must at a traditional tequila distillery (Herradura, Amatitan, Jalisco, México) were studied to gain insight on the origin of yeasts involved in a natural tequila fermentations. Five yeast communities were identified. (1) Fresh agave contained a diverse mycobiota dominated by Clavispora lusitaniae and an endemic species, Metschnikowia agaveae. (2) Drosophila spp. from around or inside the distillery yielded typical fruit yeasts, in particular Hanseniaspora spp., Pichia kluyveri, and Candida krusei. (3) Schizosaccharomyces pombe prevailed in molasses. (4) Cooked agave and extract had a considerable diversity of species, but included Saccharomyces cerevisiae. (5) Fermenting juice underwent a gradual reduction in yeast heterogeneity. Torulaspora delbrueckii, Kluyveromyces marxianus, and Hanseniaspora spp. progressively ceded the way to S. cerevisiae, Zygosaccharomyces bailii, Candida milleri, and Brettanomyces spp. With the exception of Pichia membranaefaciens, which was shared by all communities, little overlap existed. That separation was even more manifest when species were divided into distinguishable biotypes based on morphology or physiology. It is concluded that crushing equipment and must holding tanks are the main source of significant inoculum for the fermentation process. Drosophila species appear to serve as internal vectors. Proximity to fruit trees probably contributes to maintaining a substantial Drosophila community, but the yeasts found in the distillery exhibit very little similarity to those found in adjacent vegetation. Interactions involving killer toxins had no apparent direct effects on the yeast community structure. PMID:8546452

Lachance, M A

1995-08-01

343

The growth of solar radiated yeast  

SciTech Connect

This researcher plans to determine if solar radiation affects the growth of yeast. The irradiated yeast was obtained from a sample exposed in space during a Space Shuttle flight of September 9-20, 1994. Further, the control groups were held at: (1) Goddard Space Flight Center (GSFC) in Greenbelt, Maryland; and (2) South Dakota School of Mines and Technology. The procedure used was based on the fact that yeast is most often used in consumable baked goods. Therefore, the yeast was incorporated into a basic Betty Crocker bread recipe. Data was collected by placing measured amounts of dough into sample containers with fifteen minute growth in height measurements collected and recorded. This researcher assumed the viability of yeast to be relative to its ability to produce carbon dioxide gas and cause the dough to rise. As all ingredients and surroundings were equal, this researcher assumed the yeast will produce the only significant difference in data collected. This researcher noted the approximate use date on all sample packages to be prior to arrival and experiment date. All dates equal, it was then assumed each would act in a similar manner of response. This assumption will allow for equally correct data collection.

Kraft, T.

1995-09-01

344

The growth of solar radiated yeast  

NASA Technical Reports Server (NTRS)

This researcher plans to determine if solar radiation affects the growth of yeast. The irradiated yeast was obtained from a sample exposed in space during a Space Shuttle flight of September 9-20, 1994. Further, the control groups were held at: (1) Goddard Space Flight Center (GSFC) in Greenbelt, Maryland; and (2) South Dakota School of Mines and Technology. The procedure used was based on the fact that yeast is most often used in consumable baked goods. Therefore, the yeast was incorporated into a basic Betty Crocker bread recipe. Data was collected by placing measured amounts of dough into sample containers with fifteen minute growth in height measurements collected and recorded. This researcher assumed the viability of yeast to be relative to its ability to produce carbon dioxide gas and cause the dough to rise. As all ingredients and surroundings were equal, this researcher assumed the yeast will produce the only significant difference in data collected. This researcher noted the approximate use date on all sample packages to be prior to arrival and experiment date. All dates equal, it was then assumed each would act in a similar manner of response. This assumption will allow for equally correct data collection.

Kraft, Tyrone

1995-01-01

345

Glutaraldehyde enhanced dielectrophoretic yeast cell separation  

PubMed Central

We introduce a method for improved dielectrophoretic (DEP) discrimination and separation of viable and nonviable yeast cells. Due to the higher cell wall permeability of nonviable yeast cells compared with their viable counterpart, the cross-linking agent glutaraldehyde (GLT) is shown to selectively cross-link nonviable cells to a much greater extent than viable yeast. The DEP crossover frequency (cof) of both viable and nonviable yeast cells was measured over a large range of buffer conductivities (22 ?S?cm–400 ?S?cm) in order to study this effect. The results indicate that due to selective nonviable cell cross-linking, GLT modifies the DEP cof of nonviable cells, while viable cell cof remains relatively unaffected. To investigate this in more detail, a dual-shelled oblate spheroid model was evoked and fitted to the cof data to study cell electrical properties. GLT treatment is shown to minimize ion leakage out of the nonviable yeast cells by minimizing changes in cytoplasm conductivity over a large range of ionic concentrations. This effect is only observable in nonviable cells where GLT treatment serves to stabilize the cell cytoplasm conductivity over a large range of buffer conductivity and allow for much greater differences between viable and nonviable cell cofs. As such, by taking advantage of differences in cell wall permeability GLT magnifies the effect DEP has on the field induced separation of viable and nonviable yeasts. PMID:20216970

Gagnon, Zachary; Mazur, Jill; Chang, Hsueh-Chia

2009-01-01

346

Physiological and environmental control of yeast prions  

PubMed Central

Prions are self-perpetuating protein isoforms that cause fatal and incurable neurodegenerative disease in mammals. Recent evidence indicates that a majority of human proteins involved in amyloid and neural inclusion disorders possess at least some prion properties. In lower eukaryotes, such as yeast, prions act as epigenetic elements, which increase phenotypic diversity by altering a range of cellular processes. While some yeast prions are clearly pathogenic, it is also postulated that prion formation could be beneficial in variable environmental conditions. Yeast and mammalian prions have similar molecular properties. Crucial cellular factors and conditions influencing prion formation and propagation were uncovered in the yeast models. Stress-related chaperones, protein quality control deposits, degradation pathways and cytoskeletal networks control prion formation and propagation in yeast. Environmental stresses trigger prion formation and loss, supposedly acting via influencing intracellular concentrations of the prion-inducing proteins, and/or by localizing prionogenic proteins to the prion induction sites via heterologous ancillary helpers. Physiological and environmental modulation of yeast prions points to new opportunities for pharmacological intervention and/or prophylactic measures targeting general cellular systems rather than the properties of individual amyloids and prions. PMID:24236638

Chernova, Tatiana A.; Wilkinson, Keith D.; Chernoff, Yury O.

2014-01-01

347

CARACTERIZAÇÃO COLORIMÉTRICA DAS MADEIRAS DE MUIRAPIRANGA (Brosimum rubescensTaub.) E DE SERINGUEIRA (Hevea brasiliensis, clone Tjir 16 Müll Arg.) VISANDO À UTILIZAÇÃO EM INTERIORES COLORIMETRY CHARACTERIZATION OF THE WOOD OF MUIRAPIRANGA (Brosimum rubescens Taub.) AND OF RUBBER TREE (Hevea brasiliensis, clone Tjir 16 Müll Arg.) AIMING AT INSIDE USE  

Microsoft Academic Search

Although recent, the technique for the determination of wood color through the quantitative colorimetry seems to be efficient. The CIELAB 1976 system cuhich determines the L *, a *, b *, C and h * colorimetric parameters, seemed to be efficient for the determination of the color of the muirapiranga wood (Brosimum rubescens) and of rubbertree (Hevea brasiliensis, clone Tjir

Cristine da Silva Autran; Joaquim Carlos Gonçalez

2006-01-01

348

Discussion of teleomorphic and anamorphic Ascomycetous yeasts and yeast-like taxa  

Technology Transfer Automated Retrieval System (TEKTRAN)

The relationship of ascomycetous yeasts with other members of the ascomycete fungi (Ascomycota) has been controversial for over 100 years. Because yeasts are morphologically simple, it was proposed that they represent primitive forms of ascomycetes (e.g., Guilliermond 1912). Alternatively, the ide...

349

Yeast Transformation Inoculate 100 ml YPD with 1 single (reasonably fat) yeast colony at about 5  

E-print Network

. Heat shock 15 minutes at 42 C. Pellet cells 5 seconds in microfuge, discard supernatant. ResuspendAuble Lab Yeast Transformation Inoculate 100 ml YPD with 1 single (reasonably fat) yeast colony cells in 0.2 ml TE. Plate 200 µl of each transformation. Wrap plates and incubate at 30 C. #12;Auble Lab

Auble, David

350

Dacryocystitis due to Sporothrix brasiliensis: a case report of a successful clinical and serological outcome with low-dose potassium iodide treatment and oculoplastic surgery.  

PubMed

Sporothrix brasiliensis is the main species of the S. schenckii complex implicated in the zoonotic epidemics of sporotrichosis in Rio de Janeiro, Brazil. Epidemiological features have been already described, such as zoonotic transmission by cats and increased frequency of atypical clinical aspects. The involvement of the face by contact with cats is common in childhood; as a result, ophthalmic manifestations have increased. We report a case of acute dacryocystitis in a 9-year-old girl. A calmodulin-based molecular phylogeny was used to identify the agent as S. brasiliensis. This is a rare type of presentation, usually complicated with nasolacrimal duct occlusion. The patient was cured without sequelae after treatment with a low dose of saturated solution of potassium iodide and decompressive oculoplastic surgery. Therapeutic options and considerations of aetiological agents and serology are discussed. PMID:25155197

Marques de Macedo, P; Sztajnbok, D C N; Camargo, Z P; Rodrigues, A M; Lopes-Bezerra, L M; Bernardes-Engemann, A R; Orofino-Costa, R

2015-04-01

351

Yeast and human mitochondrial helicases.  

PubMed

Mitochondria are semiautonomous organelles which contain their own genome. Both maintenance and expression of mitochondrial DNA require activity of RNA and DNA helicases. In Saccharomyces cerevisiae the nuclear genome encodes four DExH/D superfamily members (MSS116, SUV3, MRH4, IRC3) that act as helicases and/or RNA chaperones. Their activity is necessary for mitochondrial RNA splicing, degradation, translation and genome maintenance. In humans the ortholog of SUV3 (hSUV3, SUPV3L1) so far is the best described mitochondrial RNA helicase. The enzyme, together with the matrix-localized pool of PNPase (PNPT1), forms an RNA-degrading complex called the mitochondrial degradosome, which localizes to distinct structures (D-foci). Global regulation of mitochondrially encoded genes can be achieved by changing mitochondrial DNA copy number. This way the proteins involved in its replication, like the Twinkle helicase (c10orf2), can indirectly regulate gene expression. Here, we describe yeast and human mitochondrial helicases that are directly involved in mitochondrial RNA metabolism, and present other helicases that participate in mitochondrial DNA replication and maintenance. This article is part of a Special Issue entitled: The Biology of RNA helicases - Modulation for life. PMID:23454114

Szczesny, Roman J; Wojcik, Magdalena A; Borowski, Lukasz S; Szewczyk, Maciej J; Skrok, Magda M; Golik, Pawel; Stepien, Piotr P

2013-08-01

352

The One Hour Yeast Proteome*  

PubMed Central

We describe the comprehensive analysis of the yeast proteome in just over one hour of optimized analysis. We achieve this expedited proteome characterization with improved sample preparation, chromatographic separations, and by using a new Orbitrap hybrid mass spectrometer equipped with a mass filter, a collision cell, a high-field Orbitrap analyzer, and, finally, a dual cell linear ion trap analyzer (Q-OT-qIT, Orbitrap Fusion). This system offers high MS2 acquisition speed of 20 Hz and detects up to 19 peptide sequences within a single second of operation. Over a 1.3 h chromatographic method, the Q-OT-qIT hybrid collected an average of 13,447 MS1 and 80,460 MS2 scans (per run) to produce 43,400 (x?) peptide spectral matches and 34,255 (x?) peptides with unique amino acid sequences (1% false discovery rate (FDR)). On average, each one hour analysis achieved detection of 3,977 proteins (1% FDR). We conclude that further improvements in mass spectrometer scan rate could render comprehensive analysis of the human proteome within a few hours. PMID:24143002

Hebert, Alexander S.; Richards, Alicia L.; Bailey, Derek J.; Ulbrich, Arne; Coughlin, Emma E.; Westphall, Michael S.; Coon, Joshua J.

2014-01-01

353

Three genes encode 3-hydroxy-3-methylglutaryl-coenzyme A reductase in Hevea brasiliensis: hmg1 and hmg3 are differentially expressed  

Microsoft Academic Search

The enzyme 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR) catalyses an important step in isoprenoid biosynthesis in plants. In Hevea brasiliensis, HMGR is encoded by a small gene family comprised of three members, hmg1, hmg2 and hmg3. We have previously described hmg1 and hmg2 (Plant Mol Biol 16: 567–577, 1991). Here we report the isolation and characterization of hmg3 genomic and cDNA clones.

Mee-Len Chye; Chio-Tee Tan; Nam-Hai Chua

1992-01-01

354

Characterization and structure elucidation of 12-hydroxyoctadec- cis-9-enoic acid in Jatropha gossypifolia and Hevea brasiliensis seed oils: a rich source of hydroxy fatty acid  

Microsoft Academic Search

The seed oils containing hydroxy fatty acids are being used in various industries such as, in the production of nylon-11, in the manufacture of multi-purpose greases, as good anti-rust, new additives in water-soluble cutting fluids, and antimicrobial activity of various derivatives of ricinoleic acid polymers. Jatropha gossypifolia and Hevea brasiliensis seed oils were found to contain 18.5% and 18.0% of

K. M. Hosamani; K. S. Katagi

2008-01-01

355

Molecular characterization of a thioredoxin h gene ( HbTRX1 ) from Hevea brasiliensis showing differential expression in latex between self-rooting juvenile clones and donor clones  

Microsoft Academic Search

The cDNA code of thioredoxin h, designated as HbTRX1, was isolated from Hevea brasiliensis by rapid amplification of cDNA ends. HbTRX1 contained a 542-bp open reading frame encoding 123 amino acids. The deduced HbTRX1 protein showing high identity to thioredoxin\\u000a h of other plant species was predicted to possess the conserved catalytic site WCXPC. Semiquantitative reverse transcription-polymerase\\u000a chain reaction analysis

Hui-Liang LiHui-Zhong; Hui-Zhong Lu; Dong Guo; Wei-Min Tian; Shi-Qing Peng

2011-01-01

356

The ecological role of killer yeasts in natural communities of yeasts.  

PubMed

The killer phenomenon of yeasts was investigated in naturally occurring yeast communities. Yeast species from communities associated with the decaying stems and fruits of cactus and the slime fluxes of trees were studied for production of killer toxins and sensitivity to killer toxins produced by other yeasts. Yeasts found in decaying fruits showed the highest incidence of killing activity (30/112), while yeasts isolated from cactus necroses and tree fluxes showed lower activity (70/699 and 11/140, respectively). Cross-reaction studies indicated that few killer-sensitive interactions occur within the same habitat at a particular time and locality, but that killer-sensitive reactions occur more frequently among yeasts from different localities and habitats. The conditions that should be optimal for killer activity were found in fruits and young rots of Opuntia cladodes where the pH is low. The fruit habitat appears to favor the establishment of killer species. Killer toxin may affect the natural distribution of the killer yeast Pichia kluyveri and the sensitive yeast Cryptococcus cereanus. Their distributions indicate that the toxin produced by P. kluyveri limits the occurrence of Cr. cereanus in fruit and Opuntia pads. In general most communities have only one killer species. Sensitive strains are more widespread than killer strains and few species appear to be immune to all toxins. Genetic study of the killer yeast P. kluyveri indicates that the mode of inheritance of killer toxin production is nuclear and not cytoplasmic as is found in Saccharomyces cerevisiae and Kluyveromyces lactis. PMID:3690423

Starmer, W T; Ganter, P F; Aberdeen, V; Lachance, M A; Phaff, H J

1987-09-01

357

Mitochondrial membrane lipidome defines yeast longevity  

PubMed Central

Our studies revealed that lithocholic acid (LCA), a bile acid, is a potent anti-aging natural compound that in yeast cultured under longevity-extending caloric restriction (CR) conditions acts in synergy with CR to enable a significant further increase in chronological lifespan. Here, we investigate a mechanism underlying this robust longevity-extending effect of LCA under CR. We found that exogenously added LCA enters yeast cells, is sorted to mitochondria, resides mainly in the inner mitochondrial membrane, and also associates with the outer mitochondrial membrane. LCA elicits an age-related remodeling of glycerophospholipid synthesis and movement within both mitochondrial membranes, thereby causing substantial changes in mitochondrial membrane lipidome and triggering major changes in mitochondrial size, number and morphology. In synergy, these changes in the membrane lipidome and morphology of mitochondria alter the age-related chronology of mitochondrial respiration, membrane potential, ATP synthesis and reactive oxygen species homeostasis. The LCA-driven alterations in the age-related dynamics of these vital mitochondrial processes extend yeast longevity. In sum, our findings suggest a mechanism underlying the ability of LCA to delay chronological aging in yeast by accumulating in both mitochondrial membranes and altering their glycerophospholipid compositions. We concluded that mitochondrial membrane lipidome plays an essential role in defining yeast longevity. PMID:23924582

Burstein, Michelle T.; Bourque, Simon D.; Koupaki, Olivia; Juneau, Mylène; Feldman, Rachel; Iouk, Tatiana; Titorenko, Vladimir I.

2013-01-01

358

Yeasts associated with Sardinian ewe's dairy products.  

PubMed

In the present work, the occurrence of yeasts in different types of typical Sardinian ewe's cheeses (32 samples of pecorino, 32 of caciotta, 40 of feta, 56 of ricotta) was determined. For the strains isolated the following properties were studied: proteolytic and lipolytic activities, the ability to grow at different temperatures, different concentrations of salt, and to assimilate and/or ferment compounds like lactate, citrate, lactose, glucose, galactose, lactic acid. Of 160 samples analysed, 76.2% yielded growth of yeasts. Yeast counts showed a certain variability among the samples. The highest levels were observed in caciotta and feta cheeses. A total of 281 strains belonging to 16 genera and 25 species were identified. In general, Debaryomyces hansenii was the dominant species, representing 28.8% of the total isolates. Other frequently appearing species were Geotrichum candidum, Kluyveromyces lactis and K. marxianus. Other genera encountered were Pichia, Candida, Dekkera, Yarrowia and Rhodotorula. With regard to the biochemical and technological properties of the yeasts, only K. lactis, K. marxianus and Dek. anomala assimilated and fermented lactose, whereas the majority of the species assimilated lactic acid. The assimilation of citrate was a characteristic of D. hansenii, R. rubra and Y. lipolytica. On the whole, the yeasts were weakly proteolytic while lipolytic activity was present in several species. A high percentage of strains showed a certain tolerance to low temperatures while only some strains of D. hansenii and K. lactis were able to grow at a 10% NaCl concentration. PMID:11589560

Cosentino, S; Fadda, M E; Deplano, M; Mulargia, A F; Palmas, F

2001-09-19

359

Sequencing and comparison of yeast species to identify genes  

E-print Network

of the yeast Saccharomyces cerevisiae based on high-quality draft sequences of three related species (S. The yeast Saccharomyces cerevisiae, for example, has enjoyed a complete genome sequence since 1996 (ref. 1

Batzoglou, Serafim

360

Discriminative Clustering of Yeast Stress Samuel Kaski1,2  

E-print Network

received much at- tention. In the budding yeast Saccharomyces cerevisiae several hundred genes out of about stress response. 1 Introduction The ability of the yeast Saccharomyces cerevisiae genome to respond to en

Kaski, Samuel

361

YEASTS FROM THE NORTH SEA AND AMOCO CADIZ OIL  

EPA Science Inventory

The species and densities of yeasts isolated from North Sea waters before and after the production of oil were compared. Debaryomyces hansenii was the predominant species, but after oil production, Candida guillieromondii, a hydrocarbonoclastic yeast, was more commonly isolated a...

362

`Injecting' yeast Daniel Riveline1,2 & Paul Nurse1  

E-print Network

the fission yeast Schizosaccharomyces pombe, we sheared local regions of individual cells with a piezoelectric. The fission yeast cell is a rod, 15 mm in length and 4 mm in diameter, with a rigid carbohydrate cell wall

Cai, Long

363

RESEARCH ARTICLE Open Access Histone modification pattern evolution after yeast  

E-print Network

RESEARCH ARTICLE Open Access Histone modification pattern evolution after yeast gene duplication for evolutionary innovations. Many studies evidenced that genetic regulatory network evolved rapidly shortly after gene duplication. In this study, we conducted detailed analyses on yeast histone modification (HM

Gu, Xun

364

Original article Chromium yeast affects growth performance but not  

E-print Network

Original article Chromium yeast affects growth performance but not whole carcass composition the effects of supplemented trivalent chromium (Cr) from chromium yeast on growth performance, carcass vs. ad libitum in other reported experiments). (© Elsevier / Inra) chromium / pig / carcass

Paris-Sud XI, Université de

365

Yeasts and yeast-like organisms associated with fruits and blossoms of different fruit trees.  

PubMed

Yeasts are common inhabitants of the phyllosphere, but our knowledge of their diversity in various plant organs is still limited. This study focused on the diversity of yeasts and yeast-like organisms associated with matured fruits and fully open blossoms of apple, plum, and pear trees, during 2 consecutive years at 3 localities in southwest Slovakia. The occurrence of yeasts and yeast-like organisms in fruit samples was 2½ times higher and the yeast community more diverse than that in blossom samples. Only 2 species (Aureobasidium pullulans and Metschnikowia pulcherrima) occurred regularly in the blossom samples, whereas Galactomyces candidus, Hanseniaspora guilliermondii, Hanseniaspora uvarum, M. pulcherrima, Pichia kluyveri, Pichia kudriavzevii, and Saccharomyces cerevisiae were the most frequently isolated species from the fruit samples. The ratio of the number of samples where only individual species were present to the number of samples where 2 or more species were found (consortium) was counted. The occurrence of individual species in comparison with consortia was much higher in blossom samples than in fruit samples. In the latter, consortia predominated. Aureobasidium pullulans, M. pulcherrima, and S. cerevisiae, isolated from both the fruits and blossoms, can be considered as resident yeast species of various fruit tree species cultivated in southwest Slovakia localities. PMID:23210991

Vadkertiová, Renáta; Molnárová, Jana; Vránová, Dana; Sláviková, Elena

2012-12-01

366

Genome update of the dimorphic human pathogenic fungi causing paracoccidioidomycosis.  

PubMed

Paracoccidiodomycosis (PCM) is a clinically important fungal disease that can acquire serious systemic forms and is caused by the thermodimorphic fungal Paracoccidioides spp. PCM is a tropical disease that is endemic in Latin America, where up to ten million people are infected; 80% of reported cases occur in Brazil, followed by Colombia and Venezuela. To enable genomic studies and to better characterize the pathogenesis of this dimorphic fungus, two reference strains of P. brasiliensis (Pb03, Pb18) and one strain of P. lutzii (Pb01) were sequenced [1]. While the initial draft assemblies were accurate in large scale structure and had high overall base quality, the sequences had frequent small scale defects such as poor quality stretches, unknown bases (N's), and artifactual deletions or nucleotide duplications, all of which caused larger scale errors in predicted gene structures. Since assembly consensus errors can now be addressed using next generation sequencing (NGS) in combination with recent methods allowing systematic assembly improvement, we re-sequenced the three reference strains of Paracoccidioides spp. using Illumina technology. We utilized the high sequencing depth to re-evaluate and improve the original assemblies generated from Sanger sequence reads, and obtained more complete and accurate reference assemblies. The new assemblies led to improved transcript predictions for the vast majority of genes of these reference strains, and often substantially corrected gene structures. These include several genes that are central to virulence or expressed during the pathogenic yeast stage in Paracoccidioides and other fungi, such as HSP90, RYP1-3, BAD1, catalase B, alpha-1,3-glucan synthase and the beta glucan synthase target gene FKS1. The improvement and validation of these reference sequences will now allow more accurate genome-based analyses. To our knowledge, this is one of the first reports of a fully automated and quality-assessed upgrade of a genome assembly and annotation for a non-model fungus. PMID:25474325

Muñoz, José F; Gallo, Juan E; Misas, Elizabeth; Priest, Margaret; Imamovic, Alma; Young, Sarah; Zeng, Qiandong; Clay, Oliver K; McEwen, Juan G; Cuomo, Christina A

2014-12-01

367

Genome Update of the Dimorphic Human Pathogenic Fungi Causing Paracoccidioidomycosis  

PubMed Central

Paracoccidiodomycosis (PCM) is a clinically important fungal disease that can acquire serious systemic forms and is caused by the thermodimorphic fungal Paracoccidioides spp. PCM is a tropical disease that is endemic in Latin America, where up to ten million people are infected; 80% of reported cases occur in Brazil, followed by Colombia and Venezuela. To enable genomic studies and to better characterize the pathogenesis of this dimorphic fungus, two reference strains of P. brasiliensis (Pb03, Pb18) and one strain of P. lutzii (Pb01) were sequenced [1]. While the initial draft assemblies were accurate in large scale structure and had high overall base quality, the sequences had frequent small scale defects such as poor quality stretches, unknown bases (N's), and artifactual deletions or nucleotide duplications, all of which caused larger scale errors in predicted gene structures. Since assembly consensus errors can now be addressed using next generation sequencing (NGS) in combination with recent methods allowing systematic assembly improvement, we re-sequenced the three reference strains of Paracoccidioides spp. using Illumina technology. We utilized the high sequencing depth to re-evaluate and improve the original assemblies generated from Sanger sequence reads, and obtained more complete and accurate reference assemblies. The new assemblies led to improved transcript predictions for the vast majority of genes of these reference strains, and often substantially corrected gene structures. These include several genes that are central to virulence or expressed during the pathogenic yeast stage in Paracoccidioides and other fungi, such as HSP90, RYP1-3, BAD1, catalase B, alpha-1,3-glucan synthase and the beta glucan synthase target gene FKS1. The improvement and validation of these reference sequences will now allow more accurate genome-based analyses. To our knowledge, this is one of the first reports of a fully automated and quality-assessed upgrade of a genome assembly and annotation for a non-model fungus. PMID:25474325

Misas, Elizabeth; Priest, Margaret; Imamovic, Alma; Young, Sarah; Zeng, Qiandong; Clay, Oliver K.; McEwen, Juan G.; Cuomo, Christina A.

2014-01-01

368

Cytotoxic Mechanism of Selenomethionine in Yeast*  

PubMed Central

Although selenium is an essential element, its excessive uptake is detrimental to living organisms. The significance of selenium for living organisms has been exploited for various purposes. However, the molecular basis of selenium toxicity is not completely understood. Here, we applied a capillary electrophoresis time-of-flight mass spectrometry-based metabolomics approach to analysis of yeast cells treated with selenomethionine. The data indicated that intracellular thiol compounds are significantly decreased, and diselenide and selenosulfide compounds are increased in selenomethionine-treated cells. The growth defect induced by selenomethionine was recovered by extracellular addition of cysteine and by genetic modification of yeast cells that have an additional de novo synthetic pathway for cysteine. Because cysteine is an intermediate of thiol compounds, these results suggested that the loss of a reduced form of thiol compounds due to selenomethionine causes a growth defect of yeast cells. PMID:22311978

Kitajima, Toshihiko; Jigami, Yoshifumi; Chiba, Yasunori

2012-01-01

369

Yeast oligo-mediated genome engineering (YOGE).  

PubMed

High-frequency oligonucleotide-directed recombination engineering (recombineering) has enabled rapid modification of several prokaryotic genomes to date. Here, we present a method for oligonucleotide-mediated recombineering in the model eukaryote and industrial production host Saccharomyces cerevisiae , which we call yeast oligo-mediated genome engineering (YOGE). Through a combination of overexpression and knockouts of relevant genes and optimization of transformation and oligonucleotide designs, we achieve high gene-modification frequencies at levels that only require screening of dozens of cells. We demonstrate the robustness of our approach in three divergent yeast strains, including those involved in industrial production of biobased chemicals. Furthermore, YOGE can be iteratively executed via cycling to generate genomic libraries up to 10 (5) individuals at each round for diversity generation. YOGE cycling alone or in combination with phenotypic selections or endonuclease-based negative genotypic selections can be used to generate modified alleles easily in yeast populations with high frequencies. PMID:24160921

DiCarlo, James E; Conley, Andrew J; Penttilä, Merja; Jäntti, Jussi; Wang, Harris H; Church, George M

2013-12-20

370

Yeast Oligo-mediated Genome Engineering (YOGE)  

PubMed Central

High-frequency oligonucleotide-directed recombination engineering (recombineering) has enabled rapid modification of several prokaryotic genomes to date. Here, we present a method for oligonucleotide-mediated recombineering in the model eukaryote and industrial production host S. cerevisiae, which we call Yeast Oligo-mediated Genome Engineering (YOGE). Through a combination of overexpression and knockouts of relevant genes and optimization of transformation and oligonucleotide designs, we achieve high gene modification frequencies at levels that only require screening of dozens of cells. We demonstrate the robustness of our approach in three divergent yeast strains, including those involved in industrial production of bio-based chemicals. Furthermore, YOGE can be iteratively executed via cycling to generate genomic libraries up to 105 individuals at each round for diversity generation. YOGE cycling alone, or in combination with phenotypic selections or endonuclease-based negative genotypic selections, can be used to easily generate modified alleles in yeast populations with high frequencies. PMID:24160921

DiCarlo, JE; Conley, AJ; Penttilä, M; Jäntti, J; Wang, HH; Church, GM

2014-01-01

371

Comparative Functional Genomics of the Fission Yeasts  

PubMed Central

The fission yeast clade, comprising Schizosaccharomyces pombe, S. octosporus, S. cryophilus and S. japonicus, occupies the basal branch of Ascomycete fungi and is an important model of eukaryote biology. A comparative annotation of these genomes identified a near extinction of transposons and the associated innovation of transposon-free centromeres. Expression analysis established that meiotic genes are subject to antisense transcription during vegetative growth, suggesting a mechanism for their tight regulation. In addition, trans-acting regulators control new genes within the context of expanded functional modules for meiosis and stress response. Differences in gene content and regulation also explain why, unlike the Saccharomycotina, fission yeasts cannot use ethanol as a primary carbon source. These analyses elucidate the genome structure and gene regulation of fission yeast and provide tools for investigation across the Schizosaccharomyces clade. PMID:21511999

Rhind, Nicholas; Chen, Zehua; Yassour, Moran; Thompson, Dawn A; Haas, Brian J; Habib, Naomi; Wapinski, Ilan; Roy, Sushmita; Lin, Michael F.; Heiman, David I; Young, Sarah K; Furuya, Kanji; Guo, Yabin; Pidoux, Alison; Chen, Huei Mei; Robbertse, Barbara; Goldberg, Jonathan M.; Aoki, Keita; Bayne, Elizabeth H.; Berlin, Aaron M; Desjardins, Christopher A.; Dobbs, Edward; Dukaj, Livio; Fan, Lin; FitzGerald, Michael G; French, Courtney; Gujja, Sharvari; Hansen, Klavs; Keifenheim, Dan; Levin, Joshua Z.; Mosher, Rebecca A.; Müller, Carolin A.; Pfiffner, Jenna; Priest, Margaret; Russ, Carsten; Smialowska, Agata; Swoboda, Peter; Sykes, Sean M; Vaughn, Matthew; Vengrova, Sonya; Yoder, Ryan; Zeng, Qiandong; Allshire, Robin; Baulcombe, David; Birren, Bruce W.; Brown, William; Ekwall, Karl; Kellis, Manolis; Leatherwood, Janet; Levin, Henry; Margalit, Hanah; Martienssen, Rob; Nieduszynski, Conrad A.; Spatafora, Joseph W.; Friedman, Nir; Dalgaard, Jacob Z.; Baumann, Peter; Niki, Hironori; Regev, Aviv; Nusbaum, Chad

2011-01-01

372

Production of ethanol by immobilized yeast cells  

SciTech Connect

Saccharomyces cerevisiae cells were immobilized in calcium alginate beads for use in the continuous production of ethanol. Yeasts were grown in medium supplemented with ethanol to selectively screen for a culture which showed the greatest tolerance to ethanol inhibition. The immobilized yeast cells were examined in a packed-bed reactor system operated under optimized parameters. Ethanol production rates, as well as residual sugar concentrations were monitored at different feedstock flow rates. The results show that the higher cell densities obtained with the immobilized system assured higher rates of ethanol production than the nonimmobilized system. 13 refs.

Williams, D.; Munnecke, D.M.

1981-08-01

373

Production of lipid compounds in the yeast Saccharomyces cerevisiae  

Microsoft Academic Search

This review describes progress using the yeast Saccharomyces cerevisiae as a model organism for the fast and efficient analysis of genes and enzyme activities involved in the lipid biosynthetic pathways of several donor organisms. Furthermore, we assess the impact of baker's yeast on the production of novel, high-value lipid compounds. Yeast can be genetically modified to produce selected substances in

M. Veen; C. Lang

2004-01-01

374

Glucose and sucrose: hazardous fast-food for industrial yeast?  

E-print Network

, such as slow or incom- plete fermentation, `off flavors' and poor maintenance of yeast vitality. Recent studies applications of yeast biotechnology, including alcoholic fermentation, bread pro- duction and the fabricationGlucose and sucrose: hazardous fast-food for industrial yeast? Kevin J. Verstrepen1,2 , Dirk

375

Gene Expression in Yeast. Helsinki 1983, ed. by M.  

E-print Network

of the Alko Yeast Symposium Korhola & E. Viiisiinen, Foundation for Fermentation Research I (1983): 19Gene Expression in Yeast. Helsinki 1983, ed. by M. Biotechnical and Industrial Proceedings-29. A RELATIONSHIP BETI^IEENCHROMATIN STRUCTUREAND GENETIC ELEMENTS AT THE YEAST HIS3 LOCUS Department of Biological

376

21 CFR 172.381 - Vitamin D2 bakers yeast.  

Code of Federal Regulations, 2013 CFR

...bakers yeast. (c) The additive may be used in yeast-leavened baked goods and baking mixes and yeast-leavened baked snack foods at levels not to exceed 400 International Units of vitamin D2 per 100 grams in the finished food. (d) To...

2013-04-01

377

21 CFR 172.381 - Vitamin D2 bakers yeast.  

Code of Federal Regulations, 2014 CFR

...bakers yeast. (c) The additive may be used in yeast-leavened baked goods and baking mixes and yeast-leavened baked snack foods at levels not to exceed 400 International Units of vitamin D2 per 100 grams in the finished food. (d) To...

2014-04-01

378

GENE ENGINEERING OF YEASTS FOR THE DEGRADATION OF HAZARDOUS WASTE  

EPA Science Inventory

The research examined the structure and function of cytochrome P-450 genes in yeast as a model for gene engineering such as eukaryotic P-450 enzymes for biodegradation of hazardous waste by yeasts. Saccharomyces cerevisiae and Candida tropicalis are two yeasts known to produce ma...

379

Fission Yeast Tel1ATM and Rad3ATR  

E-print Network

Fission Yeast Tel1ATM and Rad3ATR Promote Telomere Protection and Telomerase Recruitment Bettina A organisms, including budding and fission yeasts, Arabidopsis, Drosophila, and mammals. However, such as fission yeast and humans. Here, we demonstrate by quantitative chromatin immunoprecipitation (ChIP) assays

Nakamura, Toru M.

380

Effect of anti-glycosphingolipid monoclonal antibodies in pathogenic fungal growth and differentiation. Characterization of monoclonal antibody MEST-3 directed to Manp?1?3Manp?1?2IPC  

PubMed Central

Background Studies carried out during the 1990's demonstrated the presence of fungal glycoinositol phosphorylceramides (GIPCs) with unique structures, some of them showed reactivity with sera of patients with histoplasmosis, paracoccidioidomycosis or aspergillosis. It was also observed that fungal GIPCs were able to inhibit T lymphocyte proliferation "in vitro", and studies regarding the importance of these molecules to fungal survival showed that many species of fungi are vulnerable to inhibitors of sphingolipid biosynthesis. Results In this paper, we describe a detailed characterization of an IgG2a monoclonal antibody (mAb), termed MEST-3, directed to the Paracoccidioides brasiliensis glycolipid antigen Pb-2 (Manp?1?3Manp?1?2IPC). mAb MEST-3 also recognizes GIPCs bearing the same structure in other fungi. Studies performed on fungal cultures clearly showed the strong inhibitory activity of MEST-3 on differentiation and colony formation of Paracoccidioides brasiliensis, Histoplasma capsulatum and Sporothrix schenckii. Similar inhibitory results were observed when these fungi where incubated with a different mAb, which recognizes GIPCs bearing terminal residues of ?-D-galactofuranose linked to mannose (mAb MEST-1). On the other hand, mAb MEST-2 specifically directed to fungal glucosylceramide (GlcCer) was able to promote only a weak inhibition on fungal differentiation and colony formation. Conclusions These results strongly suggest that mAbs directed to specific glycosphingolipids are able to interfere on fungal growth and differentiation. Thus, studies on surface distribution of GIPCs in yeast and mycelium forms of fungi may yield valuable information regarding the relevance of glycosphingolipids in processes of fungal growth, morphological transition and infectivity. PMID:20156351

2010-01-01

381

Increased vascular permeability, angiogenesis and wound healing induced by the serum of natural latex of the rubber tree Hevea brasiliensis.  

PubMed

Increases in vascular permeability and angiogenesis are crucial events to wound repair, tumoral growth and revascularization of tissues submitted to ischemia. An increased vascular permeability allows a variety of cytokines and growth factors to reach the damaged tissue. Nevertheless, the angiogenesis supply tissues with a wide variety of nutrients and is also important to metabolites clearance. It has been suggested that the natural latex from Hevea brasiliensis showed wound healing properties and angiogenic activity. Thus, the purpose of this work was to characterize its angiogenic activity and its effects on vascular permeability and wound healing. The serum fraction of the latex was separated from the rubber with reduction of the pH. The activity of the dialyzed serum fraction on the vascular permeability injected in subcutaneous tissue was assayed according Mile's method. The angiogenic activity was determined using a chick embryo chorioallantoic membrane assay and its effects on the wound-healing process was determined by the rabbit ear dermal ulcer model. The serum fraction showed evident angiogenic effect and it was effective in enhancing vascular permeability. In dermal ulcers, this material significantly accelerated wound healing. Moreover, the serum fraction boiled and treated with proteases lost these activities. These results are in accordance with the enhancement of wound healing observed in clinical trials carried out with a biomembrane prepared with the same natural latex. PMID:19943314

Mendonça, Ricardo José; Maurício, Vanessa Beatriz; Teixeira, Larissa de Bortolli; Lachat, João José; Coutinho-Netto, Joaquim

2010-05-01

382

Opioid-like antinociceptive effects of oral administration of a lectin purified from the seeds of Canavalia brasiliensis.  

PubMed

The objective of this study was to evaluate the antinociceptive effects of a lectin from Canavalia brasiliensis (ConBr) when administered orally to murine models of chemical and thermal nociception. ConBr up to 100 mg/kg produced significant and dose-dependent antinociceptive effects: 81% reduction in abdominal writhing induced by 0.6% acetic acid; 26 and 52% reduction in early- and late-stage paw licking, respectively, induced by 2.5% formalin; and 155% increase in reaction latency (heightened thermal pain threshold). In all models, the antinociceptive effect was reversed by the lectin-binding carbohydrate ?-d-methyl-mannoside and by the nonselective opioid antagonist naloxone. The antinociceptive effect observed in the formalin test was inhibited by the ?-selective antagonist naltrindole and the ?-selective antagonist nor-binaltorphimine but not by the ?-selective antagonist cyprodime. In conclusion, when administered orally to Swiss mice, the ConBr lectin displayed antinociceptive activity, both peripheral and central, mediated by the opioid system and involving ?-and ?-receptors and the lectin domain. PMID:21895762

de Freitas Pires, Alana; Assreuy, Ana Maria Sampaio; Lopes, Érika Augusta Batista; Celedônio, Natália Rocha; Soares, Carlos Eduardo Alves; Rodrigues, Natália Velloso Fontenelle Camelo; Sousa, Paloma Leão; Benevides, Raquel Guimarães; Nagano, Celso Shiniti; Cavada, Benildo Sousa; Leal-Cardoso, José Henrique; Coelho-de-Souza, Andrelina Noronha; Santos, Cláudia Ferreira

2013-04-01

383

Evidence for prenatal transfer of rabies virus in the Mexican free-tailed bat (Tadarida brasiliensis Mexicana).  

PubMed

Fetuses were collected from four Mexican free-tailed bats (Tadarida brasiliensis mexicana) and a fetal bat cell (FBC) line was established and tested for its ability to support the replication of the ERA vaccine strain of rabies virus. Cytopathic effects were detected in ERA virus-inoculated as well as uninoculated FBC's. Immunofluorescent antibody testing of uninoculated FBC's provided no evidence for the presence of rabies virus. However, mice inoculated intracranially with supernatant fluid from uninoculated FBC's died. Enzyme-linked immunosorbent assay and immunofluorescent antibody testing revealed rabies virus in the brains of these mice. Tests with a panel of monoclonal antibodies indicated that the isolate was the same as that isolated from Mexican free-tailed bats from the southwestern United States. We conclude that the fetuses from which the FBC line was derived had been infected in utero with rabies virus. We believe this may represent the first observation of prenatal transfer of rabies virus in naturally infected bats. PMID:2668566

Steece, R S; Calisher, C H

1989-07-01

384

Acarine infracommunities associated with the Mexican free-tailed bat, Tadarida brasiliensis mexicana (Chiroptera: Molossidae) in arid regions of Mexico.  

PubMed

The Mexican free-tailed bat, Tadarida brasiliensis mexicana, is one of the most widely distributed bats, and its range includes the whole Mexican territory. Ectoparasites of this bat have been the subject of isolated reports, but no studies of its community ecology have been conducted. The acarine infracommunities associated with this bat were analyzed, comparing bat populations from three arid regions of Mexico: an abandoned factory in Nombre de Dios, Durango; a cave in Santiago, Nuevo León; and a church in Concepción del Oro, Zacatecas. The acarine infracommunity in Nuevo Le6n's bats exhibited the highest levels of diversity as reflected by a higher richness, a lower dominance, and a moderate and relatively homogeneous abundance in this locality in relation to the other two. This pattern is influenced by stable cave conditions relative to artificial habitats. Notwithstanding, further studies are required to determine whether or not different habitat conditions are a primary factor in the process of structuring the acari infracommunities. PMID:14765683

Guzmán-Cornejo, C; García-Prieto, L; Morales-Malacara, J B; Pérez-Ponce De León, G

2003-11-01

385

In vivo efficacy of PF1022A and nicotinic acetylcholine receptor agonists alone and in combination against Nippostrongylus brasiliensis.  

PubMed

The cyclooctadepsipeptide PF1022A and the aminophenylamidines amidantel, deacylated amidantel (dAMD) and tribendimidine were tested as examples for drug classes potentially interesting for development as anthelmintics against human helminthiases. These compounds and levamisole were tested alone and in combination to determine their efficacy against the rat hookworm Nippostrongylus brasiliensis. After three oral treatments, intestinal worms were counted. Drug effects on parasite morphology were studied using scanning electron microscopy (SEM). Plasma pharmacokinetics were determined for tribendimidine and dAMD. All drugs reduced worm burden in a dose-dependent manner, however amidantel was significantly less active than the other aminophenylamidines. Combinations of tribendimidine and dAMD with levamisole or PF1022A at suboptimal doses revealed additive effects. While PF1022A caused virtually no changes in morphology, levamisole, dAMD and tribendimidine caused severe contraction, particularly in the hind body region. Worms exposed to combinations of PF1022A and aminophenylamidines were indistinguishable from worms exposed only to aminophenylamidines. After oral treatment with tribendimidine, only the active metabolite dAMD was detectable in plasma and concentrations were not significantly different for oral treatment with dAMD. The results support further evaluation of cyclooctadepsipeptides alone and in combination with cholinergic drugs to improve efficacy. Combining these with registered drugs may help to prevent development of resistance. PMID:23742764

Kulke, Daniel; Krücken, Jürgen; Harder, Achim; Krebber, Ralph; Fraatz, Kristine; Mehlhorn, Heinz; VON Samson-Himmelstjerna, Georg

2013-09-01

386

Complete Genome Sequence Analysis of Nocardia brasiliensis HUJEG-1 Reveals a Saprobic Lifestyle and the Genes Needed for Human Pathogenesis  

PubMed Central

Nocardia brasiliensis is an important etiologic agent of mycetoma. These bacteria live as a saprobe in soil or organic material and enter the tissue via minor trauma. Mycetoma is characterized by tumefaction and the production of fistula and abscesses, with no spontaneous cure. By using mass sequencing, we determined the complete genomic nucleotide sequence of the bacteria. According to our data, the genome is a circular chromosome 9,436,348-bp long with 68% G+C content that encodes 8,414 proteins. We observed orthologs for virulence factors, a higher number of genes involved in lipid biosynthesis and catabolism, and gene clusters for the synthesis of bioactive compounds, such as antibiotics, terpenes, and polyketides. An in silico analysis of the sequence supports the conclusion that the bacteria acquired diverse genes by horizontal transfer from other soil bacteria, even from eukaryotic organisms. The genome composition reflects the evolution of bacteria via the acquisition of a large amount of DNA, which allows it to survive in new ecological niches, including humans. PMID:23755230

Vera-Cabrera, Lucio; Ortiz-Lopez, Rocio; Elizondo-Gonzalez, Ramiro; Ocampo-Candiani, Jorge

2013-01-01

387

Screening of bacterial biocontrols against sapstain fungus (Lasiodiplodia theobromae Pat.) of rubberwood (Hevea brasiliensis Muell.Arg.).  

PubMed

Diverse bacterial biocontrol agents from various sources of aerobic composts against the sapstain fungus Lasiodiplodia theobromae in rubberwood (Hevea brasiliensis) were isolated, screened and identified by various morphological, biochemical and molecular techniques. The inhibitory effect of seventeen bacterial isolates was examined and seven exhibited inhibition towards the sapstain fungus. Among the seven antagonists, six were conclusively identified as Bacillus subtilis and one as Paenibacillus polymyxa using 16S rRNA-encoding gene sequencing. This is the first report on the occurrence of P. polymyxa, a potent biofertilizer and antagonist in vermicompost. HiCrome Bacillus agar was identified as an effective medium for differentiation of B. subtilis from other Bacillus species. The present work demonstrates the efficacy of the antagonistic property of B. subtilis strains against rubberwood sapstain fungus. Culture-based antagonistic inhibition displayed by B. subtilis can be extended to cater to the biocontrol requirements of wood-based industries against the stain fungus. The study showed the utility of an integrated approach, employing morphological, biochemical and molecular tools for conclusive identification of several bacterial isolates present in aerobic composts from diverse sources. PMID:25049165

Sajitha, K L; Maria Florence, E J; Dev, Suma Arun

2014-09-01

388

Fermenting debate: do yeast undergo apoptosis?  

Microsoft Academic Search

Apoptosis is a common feature of multicellular organisms. However, the recent observations of non-metazoan cell deaths displaying morphology reminiscent of apoptosis has suggested the existence of an ancestral cell death machinery. We discuss this possibility and its implications for the use of yeast in the dissection of the metazoan apoptotic process.

Andrew Fraser; Claerwen James

1998-01-01

389

D-xylulose fermentation in yeasts  

Microsoft Academic Search

With pure D-xylulose as substrate, Schizosaccharomyces pombe produced ethanol in good yield with low quantities of polyols as by-products. Saccharomyces cerevisiae was found to be a good alcohol producer in glucose but not as good in D-xylulose. Other yeast cultures converted D-xylulose to xylitol, or D-arabitol or both, with lower ethanol yield.

Pear P. Ueng; Cecilie A. Hunter; Cheng-shung Gong; George T. Tsao

1981-01-01

390

An Engineered Yeast Efficiently Secreting Penicillin  

PubMed Central

This study aimed at developing an alternative host for the production of penicillin (PEN). As yet, the industrial production of this ?-lactam antibiotic is confined to the filamentous fungus Penicillium chrysogenum. As such, the yeast Hansenula polymorpha, a recognized producer of pharmaceuticals, represents an attractive alternative. Introduction of the P. chrysogenum gene encoding the non-ribosomal peptide synthetase (NRPS) ?-(L-?-aminoadipyl)-L-cysteinyl-D-valine synthetase (ACVS) in H. polymorpha, resulted in the production of active ACVS enzyme, when co-expressed with the Bacillus subtilis sfp gene encoding a phosphopantetheinyl transferase that activated ACVS. This represents the first example of the functional expression of a non-ribosomal peptide synthetase in yeast. Co-expression with the P. chrysogenum genes encoding the cytosolic enzyme isopenicillin N synthase as well as the two peroxisomal enzymes isopenicillin N acyl transferase (IAT) and phenylacetyl CoA ligase (PCL) resulted in production of biologically active PEN, which was efficiently secreted. The amount of secreted PEN was similar to that produced by the original P. chrysogenum NRRL1951 strain (approx. 1 mg/L). PEN production was decreased over two-fold in a yeast strain lacking peroxisomes, indicating that the peroxisomal localization of IAT and PCL is important for efficient PEN production. The breakthroughs of this work enable exploration of new yeast-based cell factories for the production of (novel) ?-lactam antibiotics as well as other natural and semi-synthetic peptides (e.g. immunosuppressive and cytostatic agents), whose production involves NRPS's. PMID:20016817

Gidijala, Loknath; Kiel, Jan A. K. W.; Douma, Rutger D.; Seifar, Reza M.; van Gulik, Walter M.; Bovenberg, Roel A. L.; Veenhuis, Marten; van der Klei, Ida J.

2009-01-01

391

Carbon source dependent promoters in yeasts  

PubMed Central

Budding yeasts are important expression hosts for the production of recombinant proteins. The choice of the right promoter is a crucial point for efficient gene expression, as most regulations take place at the transcriptional level. A wide and constantly increasing range of inducible, derepressed and constitutive promoters have been applied for gene expression in yeasts in the past; their different behaviours were a reflection of the different needs of individual processes. Within this review we summarize the majority of the large available set of carbon source dependent promoters for protein expression in yeasts, either induced or derepressed by the particular carbon source provided. We examined the most common derepressed promoters for Saccharomyces cerevisiae and other yeasts, and described carbon source inducible promoters and promoters induced by non-sugar carbon sources. A special focus is given to promoters that are activated as soon as glucose is depleted, since such promoters can be very effective and offer an uncomplicated and scalable cultivation procedure. PMID:24401081

2014-01-01

392

Heavy metal transporters in Hemiascomycete yeasts  

Microsoft Academic Search

We have compiled all known heavy metal transporters of the yeast Saccharomyces cerevisiae and identified their orthologs in four other species spanning the entire Hemiascomycete phylum. The 213 transporters belong to 27 distinct phylogenetic families distributed within the three classes: channels, secondary porters (permeases) and transport ATPases. They are present in all cellular membranes: plasma membranes, vacuoles, mitochondria, endoplasmic reticulum,

J. F. Diffels; M.-L. Seret; A. Goffeau; P. V. Baret

2006-01-01

393

Population genomics of domestic and wild yeasts  

Microsoft Academic Search

Since the completion of the genome sequence of Saccharomyces cerevisiae in 1996 (refs 1, 2), there has been a large increase in complete genome sequences, accompanied by great advances in our understanding of genome evolution. Although little is known about the natural and life histories of yeasts in the wild, there are an increasing number of studies looking at ecological

Gianni Liti; David M. Carter; Alan M. Moses; Jonas Warringer; Leopold Parts; Stephen A. James; Robert P. Davey; Ian N. Roberts; Austin Burt; Vassiliki Koufopanou; Isheng J. Tsai; Douda Bensasson; Michael J. T. O'Kelly; Alexander van Oudenaarden; David B. H. Barton; Elizabeth Bailes; Alex N. Nguyen; Matthew Jones; Michael A. Quail; Ian Goodhead; Sarah Sims; Frances Smith; Anders Blomberg; Richard Durbin; Edward J. Louis

2009-01-01

394

Movement of cortical actin patches in yeast  

Microsoft Academic Search

In yeast, actin forms patches associated with the plasma membrane. Patch distribution correlates with polarized growth during the cell cycle and in re- sponse to external stimuli. Using green fluorescent pro- tein fused to capping protein to image actin patches in living cells, we find that patches move rapidly and over long distances. Even patches in clusters, such as at

James A. Waddle; Tatiana S. Karpova; Robert H. Waterston; John A. Cooper

1996-01-01

395

YEASTBOOK PERSPECTIVES Yeast: An Experimental Organism  

E-print Network

for biology. We first summarize important contributions of yeast to eukaryotic biology that we anticipated in 1988 in our first article on the subject. We then describe transformative developments that we did Remains To Be Learned 701 Conclusion 702 Copyright © 2011 by the Genetics Society of America doi: 10

Botstein, David

396

Microfermentation Test For Identification Of Yeast  

NASA Technical Reports Server (NTRS)

Microfermentation test developed as supplementary method for use in identifying yeasts, especially in clinical and environmental studies. In comparison with traditional fermentation tests, simpler and easier, and requiries less equipment, material, and laboratory space. Results obtained in days instead of weeks.

Pierson, D. L.; Mishra, S. K.; Molina, Thomas C.

1995-01-01

397

Mechanism of Diacetyl Formation in Yeast Fermentation  

Microsoft Academic Search

DIACETYL is an important component in the flavour of food and it is known to be the chief component of the aroma of butter. We have shown that it is also found in distilled alcoholic beverages, such as whisky and cognac. The formation of diacetyl in yeast fermentation has long been known1 and extensive studies have been made of its

Heikki Suomalainen; Pentti Ronkainen

1968-01-01

398

Actin and Endocytosis in Budding Yeast  

PubMed Central

Endocytosis, the process whereby the plasma membrane invaginates to form vesicles, is essential for bringing many substances into the cell and for membrane turnover. The mechanism driving clathrin-mediated endocytosis (CME) involves > 50 different protein components assembling at a single location on the plasma membrane in a temporally ordered and hierarchal pathway. These proteins perform precisely choreographed steps that promote receptor recognition and clustering, membrane remodeling, and force-generating actin-filament assembly and turnover to drive membrane invagination and vesicle scission. Many critical aspects of the CME mechanism are conserved from yeast to mammals and were first elucidated in yeast, demonstrating that it is a powerful system for studying endocytosis. In this review, we describe our current mechanistic understanding of each step in the process of yeast CME, and the essential roles played by actin polymerization at these sites, while providing a historical perspective of how the landscape has changed since the preceding version of the YeastBook was published 17 years ago (1997). Finally, we discuss the key unresolved issues and where future studies might be headed. PMID:25657349

Goode, Bruce L.; Eskin, Julian A.; Wendland, Beverly

2015-01-01

399

Microbodies in methanol-assimilating yeasts  

Microsoft Academic Search

Cells of 3 yeast species capable of assimilating methanol have been examined by electron microscopy. When grown on methanol as the sole source of carbon and energy they contained many microbodies. Cells grown on glucose or ethanol either did not contain such bodies at all, or only to a limited extent.

J. P. van Dijken; M. Veenhuis; N. J. W. Kreger-Van Rij; W. Harder

1975-01-01

400

Genetics of a primaquin-resistant yeast.  

PubMed

Primaquin specifically inhibits mitochondrial function in yeast. Mutants resistant to primaquin have been isolated. Genetic analysis revealed that the expression of resistance in one of them was under the control of both a nuclear gene and a cytoplasmic factor (possibly a mitochondrial gene). PMID:1097590

Rotman, A

1975-07-01

401

Molecular Complementarity of Yeast Glycoprotein Mating Factors  

Microsoft Academic Search

Cell fusion between opposite mating types 5 and 21 of the yeast Hansenula wingei is initiated by a strong sexual agglutination reaction. The mating factors responsible for the specificity of cellular recognition are complementary glycoproteins which form a physical complex in vitro. The complex is assayed by recovery of agglutination activity of the multivalent 5-factor after the univalent 21-factor has

Marjorie Crandall; Lawrence M. Lawrence; Robert M. Saunders

1974-01-01

402

Antarctic Yeasts: Biodiversity and Potential Applications  

NASA Astrophysics Data System (ADS)

This review is an attempt in cataloguing the diversity of yeasts in Antarctica, highlight their biotechnological potential and understand the basis of adaptation to low temperature. As of now several psychrophilic and psychrotolerant yeasts from Antarctic soils and marine waters have been characterized with respect to their growth characteristics, ecological distribution and taxonomic significance. Interestingly most of these species belonged to basidiomycetous yeasts which as a group are known for their ability to circumvent and survive under stress conditions. Simultaneously their possible role as work horses in the biotechnological industry was recognized due to their ability to produce novel enzymes and biomolecules such as agents for the breakdown of xenobiotics, and novel pharmaceutical chemi cals. The high activity of psychrophilic enzymes at low and moderate temperatures offers potential economic benefits. As of now lipases from Pseudozyma antarctica have been extensively studied to understand their unique thermal stability at 90°C and also because of its use in the pharmaceutical, agriculture, food, cosmetics and chemical industry. A few of the other enzymes which have been studied include extracellular alpha-amylase and glucoamylase from the yeast Pseudozyma antarctica (Candida antarctica), an extra-cellular protease from Cryptococcus humicola, an aspartyl proteinase from Cryptococcus humicola, a novel extracellular subtilase from Leucosporidium antarcticum, and a xylanase from Cryptococcus adeliensis

Shivaji, S.; Prasad, G. S.

403

Copper transport in non-growing yeast  

SciTech Connect

The mandatory role of copper (Cu) proteins in cell metabolism and the speculation that Cu influences the production of porphyrins and hemoproteins prompted an examination of the regulatory features of, and the process by which Cu is taken up by yeast. Saccharomyces Cerevisiae was grown on glucose minimal media in the absence of added Cu at 29/sup 0/C, 200 rpm for 48-72 hrs. Cells were harvested and washed by centrifugation and resuspended at standardized mg dry weight/ml. The yeast was exposed to Cu under a variety of experimental conditions in 10 ml volume containing approximately 5 mg (dry wt.) yeast and Cu (0-10/sup -4/M). Reactions were stopped by microcentrifugation and Cu was determined, by difference, using atomic absorption spectrophotometry. The time course of Cu uptake reflected two phases; a rapid rate followed by a slow rate which varied according to conditions. Direct determination of Cu using washing (chelators) and ashing of washed yeast showed that the initial phase was indeed adsorption of Cu to cell exterior. While the relationship of adsorbed Cu to Cu uptake has not been evaluated the system nevertheless is being used for the determination of the effects of environmental factors (pH, (Cu), temperature, etc.) on the uptake process. Furthermore, this system provides a convenient method for characterizing the Cu-transport machinery in a static (non-growth) mode.

Turos, S.; Donahue, T.; Trent, C.; Connelly, J.L.

1986-05-01

404

Phosphorylation site on yeast pyruvate dehydrogenase complex  

SciTech Connect

The pyruvate dehydrogenase complex was purified to homogeneity from baker's yeast (Saccharomyces cerevisiae). Yeast cells were disrupted in a Manton-Gaulin laboratory homogenizer. The pyruvate dehydrogenase complex was purified by fractionation with polyethylene glycol, isoelectric precipitation, ultracentrifugation and chromatography on hydroxylapatite. Final purification of the yeast pyruvate dehydrogenase complex was achieved by cation-exchange high pressure liquid chromatography (HPLC). No endogenous pyruvate dehydrogenase kinase activity was detected during the purification. However, the yeast pyruvate dehydrogenase complex was phosphorylated and inactivated with purified pyruvate dehydrogenase kinase from bovine kidney. Tryptic digestion of the /sup 32/P-labeled complex yielded a single phosphopeptide which was purified to homogeniety. The tryptic digest was subjected to chromatography on a C-18 reverse phase HPLC column with a linear gradient of acetonitrile. Radioactive fractions were pooled, concentrated, and subjected to anion-exchange HPLC. The column was developed with a linear gradient of ammonium acetate. Final purification of the phosphopeptide was achieved by chromatography on a C-18 reverse phase HPLC column developed with a linear gradient of acetonitrile. The amino acid sequence of the homogeneous peptide was determined by manual modified Edman degradation.

Uhlinger, D.J.

1986-01-01

405

Evolution of moonlighting proteins: insight from yeasts.  

PubMed

The present article addresses the possibilities offered by yeasts to study the problem of the evolution of moonlighting proteins. It focuses on data available on hexokinase from Saccharomyces cerevisiae that moonlights in catabolite repression and on galactokinase from Kluyveromyces lactis that moonlights controlling the induction of the GAL genes. Possible experimental approaches to studying the evolution of moonlighting hexose kinases are suggested. PMID:25399595

Gancedo, Carlos; Flores, Carmen-Lisset; Gancedo, Juana M

2014-12-01

406

Molecular Evolution of Minisatellites in Hemiascomycetous Yeasts  

Microsoft Academic Search

Minisatellites are DNA tandem repeats exhibiting size polymorphism among individuals of a population. This polymor- phism is generated by two different mechanisms, both in human and yeast cells, ''replication slippage'' during S-phase DNA synthesis and ''repair slippage'' associated to meiotic gene conversion. The Saccharomyces cerevisiae genome con- tains numerous natural minisatellites. They are located on all chromosomes without any obvious

Guy-Franck Richard; Bernard Dujon

2005-01-01

407

Commitment to meiosis in fission yeast  

Microsoft Academic Search

Mutants of Schizosaccharomyces pombe blocked during meiosis were analysed with respect to the induction of diploid mitotic division. Wild type zygotes of this yeast can form diploid colonies with a low probability (ca. 1%) when they are transferred to fresh growth medium. Mutants of three genes affecting meiosis responded to the shift by forming diploid colonies with high yield (ca.

Richard Egel

1973-01-01

408

Replicon size of yeast ribosomal DNA  

Microsoft Academic Search

The ribosomal RNAs of the yeast Saccharomyces cerevisiae are transcribed from a 9Kbp stretch of DNA which is reiterated about 120-fold in a continuous array, about 360 µm long, on chromosome XII. Although ARS activity has been detected in the repeat unit, the size and disposition of replicons along this array of identical genes has not hitherto been determined. We

Richard M. Walmsley; Leland H. Johnston; Donald H. Williamson; Stephen G. Oliver

1984-01-01

409

Glucose-Induced Acidification in Yeast Cultures  

ERIC Educational Resources Information Center

We present an investigation (for A-level biology students and equivalent) into the mechanism of glucose-induced extracellular acidification in unbuffered yeast suspensions. The investigation is designed to enhance understanding of aspects of the A-level curriculum that relate to the phenomenon (notably glucose catabolism) and to develop key skills…

Myers, Alan; Bourn, Julia; Pool, Brynne

2005-01-01

410

Yeast and Egg Contamination of Shell Eggs  

Technology Transfer Automated Retrieval System (TEKTRAN)

Poultry and eggs are often contaminated with microorganisms such as bacteria, yeasts, and molds. Bacteria such as Salmonella cause illness in human who eat eggs contaminated with them, particularly if the eggs are pooled, improperly refrigerated, and eaten raw or undercooked. Other bacteria such a...

411

Global analysis of protein phosphorylation in yeast  

Microsoft Academic Search

Protein phosphorylation is estimated to affect 30% of the proteome and is a major regulatory mechanism that controls many basic cellular processes. Until recently, our biochemical understanding of protein phosphorylation on a global scale has been extremely limited; only one half of the yeast kinases have known in vivo substrates and the phosphorylating kinase is known for less than 160

Jason Ptacek; Geeta Devgan; Gregory Michaud; Heng Zhu; Xiaowei Zhu; Joseph Fasolo; Hong Guo; Ghil Jona; Ashton Breitkreutz; Richelle Sopko; Rhonda R. McCartney; Martin C. Schmidt; Najma Rachidi; Soo-Jung Lee; Angie S. Mah; Lihao Meng; Michael J. R. Stark; David F. Stern; Claudio de Virgilio; Mike Tyers; Brenda Andrews; Mark Gerstein; Barry Schweitzer; Paul F. Predki; Michael Snyder

2005-01-01

412

Homogeneity of Trypanosoma cruzi I, II, and III populations and the overlap of wild and domestic transmission cycles by Triatoma brasiliensis in northeastern Brazil.  

PubMed

The genetic variability of 24 Trypanosoma cruzi isolates from humans (11) and triatomines (13) in northeastern Brazil was analyzed by random amplified polymorphic DNA (RAPD) and compared with taxonomic groups, host, and geographical origin of the parasite. TcI (12.5%), TcII (45.8%), and TcIII (41.6%) showed a similarity coefficient (SC) of 0.74 using the mean of three primers and 0.80, 0.75, and 0.66 for ?gt11-F, M13-40F, and L15996 primers, respectively. The samples were clustered according to their phylogenetic origin in two polymorphic and divergent branches: one associated with TcI and the other with two subbranches corresponding to TcII and TcIII. TcI was only identified in humans and correlated with the Id homogenous group (0.80 SC). TcII from humans and Triatoma brasiliensis showed 0.86 SC and was clustered according monoclonal or polyclonal populations with similar RAPD profiles detected among the vector and/or humans in different municipalities. TcIII was isolated exclusively in sylvatic cycles from T. brasiliensis and Panstrongylus lutzi and showed low variability (0.84 SC) and high homology mainly among isolated populations at the same locality. The homology of T. cruzi among different hosts and locations suggests the distribution of principal clones circulating and reveals an overlapping between the sylvatic and domestic cycles in this area, where T. brasiliensis infected with TcII acts as link in both environments. This species is important to maintain TcII and TcIII in wild cycles and deserves particular attention due an emergent risk of these populations being introduced into the domestic cycle; moreover, its clinical and epidemiological implications remain unknown. PMID:23371496

da Câmara, Antonia Cláudia Jácome; Lages-Silva, Eliane; Sampaio, George Harisson Felinto; D'Ávila, Daniella Alchaar; Chiari, Egler; da Cunha Galvão, Lúcia Maria

2013-04-01

413

The impact of a dam on the helminth fauna and health of a neotropical fish species Salminus brasiliensis (Cuvier 1816) from the upper Paraná River, Brazil.  

PubMed

The aim of the present study was to detect changes in the structure of the helminth parasite infracommunities in Salminus brasiliensis (Cuvier 1816) from the floodplain of the upper Paraná River after construction of the Porto Primavera Hydroelectric Plant. A total of 126 fish in the period before the dam's construction and 56 specimens 10 years after this event were analysed. Three species of parasites were collected before the construction of the dam: Prosthenhystera obesa Diesing, 1850 (Digenea), Cladocystis intestinalis Vaz, 1932 (Digenea) and Monticellia coryphicephala Monticelli, 1892 (Cestoda), and one nematode species in the larval stage, whose identification was not possible. After dam construction, the following helminth parasites were found: C. intestinalis, M. coryphicephala, Octospiniferoides incognita, Contracaecum spp. larvae and Contracaecum sp. type 2 larvae Moravec, Kohn & Fernandes 1993. The diversity of helminth parasites measured by the Brillouin diversity index (HB) differed significantly between the pre- and post-dam periods (mean HB = 0.069 and HB = 0.2, respectively; P= 0.0479; Mann-Whitney U test). The parasite community of S. brasiliensis before the construction of the dam showed concentration of dominance (C) of P. obesa (C = 0.38), while there was no concentration of dominance of any species of parasite (C = 0.22) after the dam's construction. Before the Porto Primavera dam the relative condition factor of fish was 1.0; after the dam's construction it was 0.93 (P < 0.0001; Mann-Whitney U test). This study records the disappearance of the species P. obesa and suggests that there has been local extinction of this parasite. The results show that the anthropic influence on natural systems is interfering with the welfare and health of S. brasiliensis, reflected by its fauna of helminth parasites. PMID:22776324

Karling, L C; Isaac, A; Affonso, I P; Takemoto, R M; Pavanelli, G C

2013-06-01

414

Molecular characterization and expression analysis of the small GTPase ROP members expressed in laticifers of the rubber tree (Hevea brasiliensis).  

PubMed

ROP (Rho of plants) proteins are plant-specific Rho-type small GTPases which play important roles in cellular processes and stress responses. This study explores the characteristics and possible functions of ROPs that are expressed primarily in laticifers of the rubber tree (Hevea brasiliensis). The work serves as a preliminary step to determining their involvement in latex flow and regeneration, laticifers formation and tapping panel dryness (TPD, a physiological disorder in rubber trees that result in the stoppage of latex flow). In this connection, we (i) identified five HbROPs (HbROP1-HbROP5) by searching latex transcripts database and the genome databases, (ii) characterized molecular and phylogenic aspects of the HbROPs and examined the cis-regulatory elements in their promoter regions; (iii) analyzed by Real-time Quantitative PCR (QPCR) the tissue specificity of the HbROPs and their expression patterns in response to tapping, bark wounding and growth regulator treatments. All five HbROP genes were strongly expressed in the latex, with HbROP1, 3, 4 and 5 showing the highest expression among the six Hevea tissues examined, viz. latex, bud, mature leaf, bark, male flower and seed. When tapping was initiated on previously untapped trees, HbROP3 transcription was substantially down-regulated whereas HbROP5 expression was markedly up-regulated. Transcripts of HbROP3 rose gradually with the development of TPD. Except for the cytokinin 6-benzyl aminopurine that induced a rise in HbROP5 transcripts by more than 2-fold, the other growth regulators tested had little effect on HbROPs expression. The roles of HbROPs in rubber tree are discussed in relation to the diverse functions of ROP homologs reported in other plant species. PMID:24308989

Qin, Yunxia; Huang, Yacheng; Fang, Yongjun; Qi, Jiyan; Tang, Chaorong

2014-01-01

415

Parasites of Urophycis brasiliensis (Gadiformes: Phycidae) as indicators of marine ecoregions in coastal areas of the South American Atlantic.  

PubMed

The potential value of parasites as ecosystem markers was tested by analyzing the metazoan assemblages of Urophycis brasiliensis caught in four locations distributed in three ecoregions of the Warm Temperate Southwestern Atlantic. A total of 5,001 metazoan parasites belonging to 33 species were found. The identified parasites varied across locations in terms of presence, prevalence, and abundance, and their multivariate analyses resulted in clear similarity patterns. No differences were observed between two locations of the same ecoregion, whereas an evident separation of samples was observed across ecoregions in support of the existing hypotheses regarding the ecoregional division of the southwestern Atlantic. We proposed that parasite assemblages, which are composed of several metazoan phyla, are potentially useful as ecosystem indicators. This suggestion is derived from the combined evidence of the evolutionary history and biogeography of multiple lineages, which is expected to be more efficient in capturing recurrent patterns in overall biodiversity than individual lineages. Furthermore, as many parasites have complex life cycles, their distribution patterns are dependent not only on environmental conditions but also on the distribution and population density of all hosts involved in their life cycles, adding further sources of distributional variability that act synergistically to define robust geographical patterns. The selection of long-lived parasites and their comparative analysis provided evidence supporting the existence of three different stocks in the four sampled areas. The best parasite tags were those with low specificity in fish hosts, constituting promising biological tags for the stock discrimination of other fish species in the region. PMID:25245108

Pereira, Aldenice N; Pantoja, Camila; Luque, José L; Timi, Juan T

2014-11-01

416

Prevalence of rabies specific antibodies in the Mexican free-tailed bat (Tadarida brasiliensis mexicana) at Lava Cave, New Mexico.  

PubMed

Adult female and juvenile Mexican free-tailed bats (Tadarida brasiliensis mexicana) were collected bimonthly at Lava Cave, New Mexico from May through September. The purpose of this study was to examine the prevalence of active rabies infection as well as to determine individual immune status in these hosts. All bats were bled and examined for rabies antibody (total antibody versus IgM) utilizing a modified serum neutralization test. The brains were removed and examined by the fluorescent rabies antibody (FRA) test. No significant difference was observed in the number of adults with rabies neutralizing antibody (total) over the study period. Significant differences in rabies neutralizing antibody (total) were observed among the juveniles sampled during July and August. The number of adults with IgM specific antibody was low (15 of 750, 2%) and did not fluctuate significantly. However, the number of juveniles with IgM antibody did show increased levels in August and September. The number of adults positive by the FRA was low (4 of 750, less than 1%) and did not appear to fluctuate significantly over the study period. The number of juveniles positive by the FRA was three and one-half times higher than observed for the adults (14 of 600, 2%). These results indicate that the Mexican free-tailed bat appears to be exposed to rabies virus shortly after birth as evident by its immune status. The low prevalence (4 of 750, less than 1%) of active infection as determined by the FRA and mouse inoculation and the high prevalence (514 of 750, 69%) of IgG antibody in the adult females indicate that the Mexican free-tailed bat recovers from rabies virus infection. PMID:2681843

Steece, R; Altenbach, J S

1989-10-01

417

Demography of the giant otter (Pteronura brasiliensis) in Manu National Park, south-eastern Peru: implications for conservation.  

PubMed

The giant otter (Pteronura brasiliensis) is an endangered semi-aquatic carnivore of South America. We present findings on the demography of a population inhabiting the floodplain of Manu National Park, south-eastern Peru, arising from 14 annual dry season censuses over a 16 year period. The breeding system of territorial groups, including only a single breeding female with non-reproductive adult 'helpers', resulted in a low intrinsic rate of increase (0.03) and a slow recovery from decades of hunting for the pelt trade. This is explained by a combination of factors: (1) physiological traits such as late age at first reproduction and long generation time, (2) a high degree of reproductive skew, (3) small litters produced only once a year, and (4) a 50% mortality between den emergence and age of dispersal, as well as high mortality amongst dispersers (especially males). Female and male giant otters show similar traits with respect to average reproductive life-spans (female 5.4 yrs., male 5.2 yrs.) and average cub productivity (female 6.9, male 6.7 cubs per lifetime); the longest reproductive life spans were 11 and 13 years respectively. Individual reproductive success varied substantially and depended mainly on the duration of dominance tenure in the territory. When breeding females died, the reproductive position in the group was usually occupied by sisters or daughters (n?=?11), with immigrant male partners. Male philopatry was not observed. The vulnerability of the Manu giant otter population to anthropogenic disturbance emphasises the importance of effective protection of core lake habitats in particular. Riverine forests are the most endangered ecosystem in the Department of Madre de Dios due to the concentration of gold mining, logging and agricultural activities in floodplains, highlighting the need for a giant otter habitat conservation corridor along the Madre de Dios River. PMID:25162684

Groenendijk, Jessica; Hajek, Frank; Johnson, Paul J; Macdonald, David W; Calvimontes, Jorge; Staib, Elke; Schenck, Christof

2014-01-01

418

Demography of the Giant Otter (Pteronura brasiliensis) in Manu National Park, South-Eastern Peru: Implications for Conservation  

PubMed Central

The giant otter (Pteronura brasiliensis) is an endangered semi-aquatic carnivore of South America. We present findings on the demography of a population inhabiting the floodplain of Manu National Park, south-eastern Peru, arising from 14 annual dry season censuses over a 16 year period. The breeding system of territorial groups, including only a single breeding female with non-reproductive adult ‘helpers’, resulted in a low intrinsic rate of increase (0.03) and a slow recovery from decades of hunting for the pelt trade. This is explained by a combination of factors: (1) physiological traits such as late age at first reproduction and long generation time, (2) a high degree of reproductive skew, (3) small litters produced only once a year, and (4) a 50% mortality between den emergence and age of dispersal, as well as high mortality amongst dispersers (especially males). Female and male giant otters show similar traits with respect to average reproductive life-spans (female 5.4 yrs., male 5.2 yrs.) and average cub productivity (female 6.9, male 6.7 cubs per lifetime); the longest reproductive life spans were 11 and 13 years respectively. Individual reproductive success varied substantially and depended mainly on the duration of dominance tenure in the territory. When breeding females died, the reproductive position in the group was usually occupied by sisters or daughters (n?=?11), with immigrant male partners. Male philopatry was not observed. The vulnerability of the Manu giant otter population to anthropogenic disturbance emphasises the importance of effective protection of core lake habitats in particular. Riverine forests are the most endangered ecosystem in the Department of Madre de Dios due to the concentration of gold mining, logging and agricultural activities in floodplains, highlighting the need for a giant otter habitat conservation corridor along the Madre de Dios River. PMID:25162684

Groenendijk, Jessica; Hajek, Frank; Johnson, Paul J.; Macdonald, David W.; Calvimontes, Jorge; Staib, Elke; Schenck, Christof

2014-01-01

419

Cloning whole bacterial genomes in yeast  

PubMed Central

Most microbes have not been cultured, and many of those that are cultivatable are difficult, dangerous or expensive to propagate or are genetically intractable. Routine cloning of large genome fractions or whole genomes from these organisms would significantly enhance their discovery and genetic and functional characterization. Here we report the cloning of whole bacterial genomes in the yeast Saccharomyces cerevisiae as single-DNA molecules. We cloned the genomes of Mycoplasma genitalium (0.6 Mb), M. pneumoniae (0.8 Mb) and M. mycoides subspecies capri (1.1 Mb) as yeast circular centromeric plasmids. These genomes appear to be stably maintained in a host that has efficient, well-established methods for DNA manipulation. PMID:20211840

Benders, Gwynedd A.; Noskov, Vladimir N.; Denisova, Evgeniya A.; Lartigue, Carole; Gibson, Daniel G.; Assad-Garcia, Nacyra; Chuang, Ray-Yuan; Carrera, William; Moodie, Monzia; Algire, Mikkel A.; Phan, Quang; Alperovich, Nina; Vashee, Sanjay; Merryman, Chuck; Venter, J. Craig; Smith, Hamilton O.; Glass, John I.; Hutchison, Clyde A.

2010-01-01

420

Aneuploidy causes proteotoxic stress in yeast.  

PubMed

Gains or losses of entire chromosomes lead to aneuploidy, a condition tolerated poorly in all eukaryotes analyzed to date. How aneuploidy affects organismal and cellular physiology is poorly understood. We found that aneuploid budding yeast cells are under proteotoxic stress. Aneuploid strains are prone to aggregation of endogenous proteins as well as of ectopically expressed hard-to-fold proteins such as those containing polyglutamine (polyQ) stretches. Protein aggregate formation in aneuploid yeast strains is likely due to limiting protein quality-control systems, since the proteasome and at least one chaperone family, Hsp90, are compromised in many aneuploid strains. The link between aneuploidy and the formation and persistence of protein aggregates could have important implications for diseases such as cancer and neurodegeneration. PMID:23222101

Oromendia, Ana B; Dodgson, Stacie E; Amon, Angelika

2012-12-15

421

Mapping the functional yeast ABC transporter interactome  

PubMed Central

ABC transporters are a ubiquitous class of integral membrane proteins of immense clinical interest because of their strong association with human disease and pharmacology. To improve our understanding of these proteins, we used Membrane Yeast Two-Hybrid (MYTH) technology to map the protein interactome of all non-mitochondrial ABC transporters in the model organism Saccharomy cescerevisiae, and combined this data with previously reported yeast ABC transporter interactions in the BioGRID database to generate a comprehensive, integrated interactome. We show that ABC transporters physically associate with proteins involved in a surprisingly diverse range of functions. We specifically examine the importance of the physical interactions of ABC transporters in both the regulation of one another and in the modulation of proteins involved in zinc homeostasis. The interaction network presented here will be a powerful resource for increasing our fundamental understanding of the cellular role and regulation of ABC transporters. PMID:23831759

Snider, Jamie; Hanif, Asad; Lee, Mid Eum; Jin, Ke; Yu, Analyn R.; Graham, Chris; Chuk, Matthew; Damjanovic, Dunja; Wierzbicka, Marta; Tang, Priscilla; Balderes, Dina; Wong, Victoria; Jessulat, Matthew; Darowski, Katelyn D.; Luis, Bryan-Joseph San; Shevelev, Igor; Sturley, Stephen L; Boone, Charles; Greenblatt, Jack F.; Zhang, Zhaolei; Paumi, Christian M.; Babu, Mohan; Park, Hay-Oak; Michaelis, Susan; Stagljar, Igor

2013-01-01

422

Uncommon opportunistic yeast bloodstream infections from Qatar.  

PubMed

Eleven uncommon yeast species that are associated with high mortality rates irrespective of antifungal therapy were isolated from 17/187 (201 episodes) pediatric and elderly patients with fungemia from Qatar. The samples were taken over a 6-year period (January 2004-December 2010). Isolated species included Kluyveromyces marxianus, Lodderomyces elongisporus, Lindnera fabianii, Candida dubliniensis, Meyerozyma guilliermondii, Candida intermedia, Pichia kudriavzevii, Yarrowia lipolytica, Clavispora lusitaniae, Candida pararugosa, and Wickerhamomyces anomalus. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry provided correct identifications compared with molecular analysis testing of the same isolates. Low minimal inhibitory concentrations were found when isavuconazole and voriconazole were used for all uncommon yeast species evaluated in this study. Resistance to antifungal drugs was low and remained restricted to a few species. PMID:24934803

Taj-Aldeen, Saad J; AbdulWahab, Atqah; Kolecka, Anna; Deshmukh, Anand; Meis, Jacques F; Boekhout, Teun

2014-07-01

423

Aneuploidy causes proteotoxic stress in yeast  

PubMed Central

Gains or losses of entire chromosomes lead to aneuploidy, a condition tolerated poorly in all eukaryotes analyzed to date. How aneuploidy affects organismal and cellular physiology is poorly understood. We found that aneuploid budding yeast cells are under proteotoxic stress. Aneuploid strains are prone to aggregation of endogenous proteins as well as of ectopically expressed hard-to-fold proteins such as those containing polyglutamine (polyQ) stretches. Protein aggregate formation in aneuploid yeast strains is likely due to limiting protein quality-control systems, since the proteasome and at least one chaperone family, Hsp90, are compromised in many aneuploid strains. The link between aneuploidy and the formation and persistence of protein aggregates could have important implications for diseases such as cancer and neurodegeneration. PMID:23222101

Oromendia, Ana B.; Dodgson, Stacie E.; Amon, Angelika

2012-01-01

424

Stochasticity in the yeast mating pathway  

NASA Astrophysics Data System (ADS)

We report stochastic simulations of the yeast mating signal transduction pathway. The effects of intrinsic and external noise, the influence of cell-to-cell difference in the pathway capacity, and noise propagation in the pathway have been examined. The stochastic temporal behaviour of the pathway is found to be robust to the influence of inherent fluctuations, and intrinsic noise propagates in the pathway in a uniform pattern when the yeasts are treated with pheromones of different stimulus strengths and of varied fluctuations. In agreement with recent experimental findings, extrinsic noise is found to play a more prominent role than intrinsic noise in the variability of proteins. The occurrence frequency for the reactions in the pathway are also examined and a more compact network is obtained by dropping most of the reactions of least occurrence.

Wang, Hong-Li; Fu, Zheng-Ping; Xu, Xin-Hang; Ouyang, Qi

2009-05-01

425

Towards industrial pentose-fermenting yeast strains  

Microsoft Academic Search

Production of bioethanol from forest and agricultural products requires a fermenting organism that converts all types of sugars\\u000a in the raw material to ethanol in high yield and with a high rate. This review summarizes recent research aiming at developing\\u000a industrial strains of Saccharomyces cerevisiae with the ability to ferment all lignocellulose-derived sugars. The properties required from the industrial yeast

Bärbel Hahn-Hägerdal; Kaisa Karhumaa; César Fonseca; Isabel Spencer-Martins; Marie F. Gorwa-Grauslund

2007-01-01

426

Phytase of the yeast Arxula adeninivorans  

Microsoft Academic Search

Of a number of yeasts screened for growth on phytic acid (inositol phosphates) as a sole source of carbon and phosphate, Arxula adeninivorans showed a particularly vigorous growth. This capacity was correlated with the presence of a high activity of secreted phytase. The crude enzyme showed an optimal temperature of at least 75?°C and an optimal pH of 4.5. The

Konosuke Sano; Hiroshi Fukuhara; Yoshihiro Nakamura

1999-01-01

427

Dehydrogenase activity measurement in yeast fermentation  

Microsoft Academic Search

The dehydrogenase activity was used as a measure of active biomass in preference to other biochemical parameters because of\\u000a the simple, but accurate nature of the dehydrogenase test. After a consierable amount of experimental work on the dehydrogenase\\u000a activity measurement technique and the consideration of utilization of the technique as a measure of the active biomass in\\u000a yeast fermentation systems,

A. E. Ghaly; R. M. Ben-Hassan

1993-01-01

428

Diversity of salt response among yeasts  

Microsoft Academic Search

Forty-two yeast strains from 27 species belonging to seven genera, selected for their ability to grow in 10% NaCl, have been\\u000a analysed for their resistance to salt concentrations up to 5 M, by calculating the Minimum Inhibitory Concentrations (MIC).\\u000a Using eight different NaCl concentrations from 0 to 5M, results show that halotolerance (MIC) ranges from 1.7 to 3.8 M NaCl,

Laura Corte; Paolo Rellini; Monia Lattanzi; Cristina Picchetta; Fabrizio Fatichenti; Gianluigi Cardinali

2006-01-01

429

An Engineered Yeast Efficiently Secreting Penicillin  

Microsoft Academic Search

This study aimed at developing an alternative host for the production of penicillin (PEN). As yet, the industrial production of this ?-lactam antibiotic is confined to the filamentous fungus Penicillium chrysogenum. As such, the yeast Hansenula polymorpha, a recognized producer of pharmaceuticals, represents an attractive alternative. Introduction of the P. chrysogenum gene encoding the non-ribosomal peptide synthetase (NRPS) ?-(L-?-aminoadipyl)-L-cysteinyl-D-valine synthetase

Loknath Gidijala; Jan A. K. W. Kiel; Rutger D. Douma; Reza M. Seifar; Walter M. van Gulik; Roel A. L. Bovenberg; Marten Veenhuis; Ida J. van der Klei; Paulo Lee Ho

2009-01-01

430

Complete DNA sequence of yeast chromosome XI  

Microsoft Academic Search

The complete DNA sequence of the yeast Saccharomyces cerevisiae chromosome XI has been determined. In addition to a compact arrangement of potential protein coding sequences, the 666,448-base-pair sequence has revealed general chromosome patterns; in particular, alternating regional variations in average base composition correlate with variations in local gene density along the chromosome. Significant discrepancies with the previously published genetic map

B. Dujon; D. Alexandraki; B. André; W. Ansorge; V. Baladron; J. P. G. Ballesta; A. Banrevi; P. A. Bolle; M. Bolotin-Fukuhara; P. Bossier; G. Bou; J. Boyer; M. J. Buitrago; G. Cherét; L. Colleaux; B. Dalgnan-Fornier; F. Del Rey; C. Dion; H. Domdey; A. Düsterhöft; S. Düsterhus; K.-D. Entian; H. Erfle; P. F. Esteban; H. Feldmann; L. Fernandes; G. M. Fobo; C. Fritz; H. Fukuhara; C. Gabel; L. Gaillon; J. M. Carcia-Cantalejo; J. J. Garcia-Ramirez; M. E. Gent; M. Ghazvini; A. Goffeau; A. Gonzaléz; D. Grothues; P. Guerreiro; J. Hegemann; N. Hewitt; F. Hilger; C. P. Hollenberg; O. Horaitis; K. J. Indge; A. Jacquier; C. M. James; J. C. Jauniaux; A. Jimenez; H. Keuchel; L. Kirchrath; K. Kleine; P. Kötter; P. Legrain; S. Liebl; E. J. Louis; A. Maia E Silva; C. Marck; A.-L. Monnier; D. Möstl; S. Müller; B. Obermaier; S. G. Oliver; C. Pallier; S. Pascolo; F. Pfeiffer; P. Philippsen; R. J. Planta; F. M. Pohl; T. M. Pohl; R. Pöhlmann; D. Portetelle; B. Purnelle; V. Puzos; M. Ramezani Rad; S. W. Rasmussen; M. Remacha; J. L. Revuelta; G.-F. Richard; M. Rieger; C. Rodrigues-Pousada; M. Rose; T. Rupp; M. A. Santos; C. Schwager; C. Sensen; J. Skala; H. Soares; F. Sor; J. Stegemann; H. Tettelin; A. Thierry; M. Tzermia; L. A. Urrestarazu; L. van Dyck; J. C. van Vliet-Reedijk; M. Valens; M. Vandenbo; C. Vilela; S. Vissers; D. von Wettstein; H. Voss; S. Wiemann; G. Xu; J. Zimmermann; M. Haasemann; I. Becker; H. W. Mewes

1994-01-01

431

A Sampling of the Yeast Proteome  

Microsoft Academic Search

In this study, we examined yeast proteins by two-dimensional (2D) gel electrophoresis and gathered quan- titative information from about 1,400 spots. We found that there is an enormous range of protein abundance and, for identified spots, a good correlation between protein abundance, mRNA abundance, and codon bias. For each molecule of well-translated mRNA, there were about 4,000 molecules of protein.

B. FUTCHER; G. I. LATTER; P. MONARDO; C. S. MCLAUGHLIN; J. I. GARRELS

1999-01-01

432

Typing of Histoplasma capsulatum strains by fatty acid profile analysis  

PubMed Central

The performance of fatty acid profiling for strain differentiation of Histoplasma capsulatum was assessed. Total fatty acids were isolated from the yeast-phase cells of seven stock and two previously unreported clinical strains of H. capsulatum var. capsulatum, as well as from one unreported clinical strain and one stock strain of H. capsulatum var. duboisii, and one strain of each of three other dimorphic zoopathogenic fungal species, Blastomyces dermatitidis, Paracoccidioides brasiliensis and Sporothrix schenckii. Different colony morphology and pigmentation types of the H. capsulatum strains were also included. The most frequently occurring fatty acids were oleic, palmitic, stearic and linoleic acids. There were variations in the relative percentage fatty acid contents of H. capsulatum strains that could be used for strain identification and discrimination. Differentiation between H. capsulatum strains was achieved by the comparison of detected fatty acids accompanied by principal component analysis using calculated Varimax-rotated principal component loadings. Statistical analysis yielded three major principal components that explained over 94% of total variance in the data. All the strains of H. capsulatum var. capsulatum RFLP classes II and III were grouped into two distinct clusters: the heterogenic RFLP class I formed a large, but also well-defined group, whereas the outgroup strains of H. capsulatum var. duboisii, B. dermatitidis, P. brasiliensis and S. schenckii were shifted away. These data suggest that fatty acid profiling can be used in H. capsulatum strain classification and epidemiological studies that require strain differentiation at the intraspecies level. PMID:17510264

Zarnowski, Robert; Miyazaki, Makoto; Dobrzyn, Agnieszka; Ntambi, James M.; Woods, Jon P.

2009-01-01

433

Production of recombinant proteins by yeast cells.  

PubMed

Yeasts are widely used in production of recombinant proteins of medical or industrial interest. For each individual product, the most suitable expression system has to be identified and optimized, both on the genetic and fermentative level, by taking into account the properties of the product, the organism and the expression cassette. There is a wide range of important yeast expression hosts including the species Saccharomyces cerevisiae, Pichia pastoris, Hansenula polymorpha, Kluyveromyces lactis, Schizosaccharomyces pombe, Yarrowia lipolytica and Arxula adeninivorans, with various characteristics such as being thermo-tolerant or halo-tolerant, rapidly reaching high cell densities or utilizing unusual carbon sources. Several strains were also engineered to have further advantages, such as humanized glycosylation pathways or lack of proteases. Additionally, with a large variety of vectors, promoters and selection markers to choose from, combined with the accumulated knowledge on industrial-scale fermentation techniques and the current advances in the post-genomic technology, it is possible to design more cost-effective expression systems in order to meet the increasing demand for recombinant proteins and glycoproteins. In this review, the present status of the main and most promising yeast expression systems is discussed. PMID:21964262

Celik, Eda; Cal?k, P?nar

2012-01-01

434

Screening of yeast strains for phytase activity.  

PubMed

A screening method was developed to elucidate the ability of different yeast strains to utilize phytic acid as sole phosphorus source. The growth test in liquid culture in a microtiter plate with phytic acid as sole phosphorus source was shown to be a reliable, fast and easy-to-use screening method. We tested 122 strains from 61 species with our method and observed growth differences among species and strains that were not detectable on solid medium. Specific phytase activities were measured for 10 yeasts strains, selected due to their strong growth in the liquid medium. Strains of Arxula adeninivorans and Pichia anomala reached the highest volumetric phytase activities. Arxula adeninivorans also displayed the highest intra- and extracellular specific activities.