expression systems yield: Topics by Science.gov

Sample records for expression systems yield

High-yield, in vitro protein expression using a continuous-exchange, coupled transcription/ translation system.

PubMed

Martin, G A; Kawaguchi, R; Lam, Y; DeGiovanni, A; Fukushima, M; Mutter, W

2001-10-01

The Rapid Translation System (RTS 500) (Roche Molecular Biochemicals) is a high-yield protein expression system that utilizes an enhanced E. coli lysate for an in vitro transcription/translation reaction. In contrast to conventional transcription/translation, this system allows protein expression to continue for more than 24 h. We demonstrated the utility of the RTS 500 by expressing different soluble and active proteins that generally pose problems in cell-based expression systems. We first expressed GFP-lunasin, a fusion protein that, because of its toxicity, has been impossible to produce in whole cells. The second protein we expressed, human interleukin-2 (IL-2), is generally difficult to produce, either as the native molecule or as a GSTfusion protein, in a soluble form in bacteria. Finally, we demonstrated the capacity of the RTS 500 to co-express proteins, by the simultaneous production of GFP and CAT in a single reaction. This new technology appears to be particularly usefulfor the convenient production of preparative amounts (100-900 microg) of proteins that are toxic or insoluble in cell-based systems.
Choosing Between Yeast and Bacterial Expression Systems: Yield Dependent

NASA Technical Reports Server (NTRS)

Miller, Rebecca S.; Malone, Christine C.; Moore, Blake P.; Burk, Melissa; Crawford, Lisa; Karr, Laurel J.; Curreri, Peter A. (Technical Monitor)

2002-01-01

Green fluorescent protein (GFP) is a naturally occurring fluorescent protein isolated from the jellyfish Aequorea victoria. The intrinsic fluorescence of the protein is due to a chromophore located in the center of the molecule. Its usefulness has been established as a marker for gene expression and localization of gene products. GFP has recently been utilized as a model protein for crystallization studies at NASA/MSFC, both in earth-based and in microgravity experiments. Because large quantities of purified protein were needed, the cDNA of GFP was cloned into the Pichia pastoris pPICZ(alpha) C strain, with very little protein secreted into the media. Microscopic analysis prior to harvest showed gigantic green fluorescent yeast, but upon harvesting most protein was degraded. Trial fermentations of GFP cloned into pPICZ A for intracellular expression provided unsatisfactory yield. GFP cloned into E, coli was overexpressed at greater than 150 mg/liter, with purification yields at greater than 100mg/liter.
Increasing the yield of middle silk gland expression system through transgenic knock-down of endogenous sericin-1.

PubMed

Ma, Sanyuan; Xia, Xiaojuan; Li, Yufeng; Sun, Le; Liu, Yue; Liu, Yuanyuan; Wang, Xiaogang; Shi, Run; Chang, Jiasong; Zhao, Ping; Xia, Qingyou

2017-08-01

Various genetically modified bioreactor systems have been developed to meet the increasing demands of recombinant proteins. Silk gland of Bombyx mori holds great potential to be a cost-effective bioreactor for commercial-scale production of recombinant proteins. However, the actual yields of proteins obtained from the current silk gland expression systems are too low for the proteins to be dissolved and purified in a large scale. Here, we proposed a strategy that reducing endogenous sericin proteins would increase the expression yield of foreign proteins. Using transgenic RNA interference, we successfully reduced the expression of BmSer1 to 50%. A total 26 transgenic lines expressing Discosoma sp. red fluorescent protein (DsRed) in the middle silk gland (MSG) under the control of BmSer1 promoter were established to analyze the expression of recombinant. qRT-PCR and western blotting showed that in BmSer1 knock-down lines, the expression of DsRed had significantly increased both at mRNA and protein levels. We did an additional analysis of DsRed/BmSer1 distribution in cocoon and effect of DsRed protein accumulation on the silk fiber formation process. This study describes not only a novel method to enhance recombinant protein expression in MSG bioreactor, but also a strategy to optimize other bioreactor systems.
A gene co-expression network model identifies yield-related vicinity networks in Jatropha curcas shoot system.

PubMed

Govender, Nisha; Senan, Siju; Mohamed-Hussein, Zeti-Azura; Wickneswari, Ratnam

2018-06-15

The plant shoot system consists of reproductive organs such as inflorescences, buds and fruits, and the vegetative leaves and stems. In this study, the reproductive part of the Jatropha curcas shoot system, which includes the aerial shoots, shoots bearing the inflorescence and inflorescence were investigated in regard to gene-to-gene interactions underpinning yield-related biological processes. An RNA-seq based sequencing of shoot tissues performed on an Illumina HiSeq. 2500 platform generated 18 transcriptomes. Using the reference genome-based mapping approach, a total of 64 361 genes was identified in all samples and the data was annotated against the non-redundant database by the BLAST2GO Pro. Suite. After removing the outlier genes and samples, a total of 12 734 genes across 17 samples were subjected to gene co-expression network construction using petal, an R library. A gene co-expression network model built with scale-free and small-world properties extracted four vicinity networks (VNs) with putative involvement in yield-related biological processes as follow; heat stress tolerance, floral and shoot meristem differentiation, biosynthesis of chlorophyll molecules and laticifers, cell wall metabolism and epigenetic regulations. Our VNs revealed putative key players that could be adapted in breeding strategies for J. curcas shoot system improvements.
TPS1 terminator increases mRNA and protein yield in a Saccharomyces cerevisiae expression system.

PubMed

Yamanishi, Mamoru; Katahira, Satoshi; Matsuyama, Takashi

2011-01-01

Both terminators and promoters regulate gene expression. In Saccharomyces cerevisiae, the TPS1 terminator (TPS1t), coupled to a gene encoding a fluorescent protein, produced more transgenic mRNA and protein than did similar constructs containing other terminators, such as CYC1t, TDH3t, and PGK1t. This suggests that TPS1t can be used as a general terminator in the development of metabolically engineered yeast in high-yield systems.
Laue Crystal Structure of Shewanella oneidensis Cytochrome c Nitrite Reductase from a High-yield Expression System

PubMed Central

Youngblut, Matthew; Judd, Evan T.; Srajer, Vukica; Sayyed, Bilal; Goelzer, Tyler; Elliott, Sean J.; Schmidt, Marius; Pacheco, A. Andrew

2012-01-01

The high-yield expression and purification of Shewanella oneidensis cytochrome c nitrite reductase (ccNiR), and its characterization by a variety of methods, notably Laue crystallography, is reported. A key component of the expression system is an artificial ccNiR gene in which the N-terminal signal peptide from the highly expressed S. oneidensis protein “Small Tetra-heme c” replaces the wild-type signal peptide. This gene, inserted into the plasmid pHSG298 and expressed in S. oneidensis TSP-1 strain, generated ~20 mg crude ccNiR/L culture, compared with 0.5–1 mg/L for untransformed cells. Purified ccNiR has nitrite and hydroxylamine reductase activities comparable to those previously reported for E. coli ccNiR, and is stable for over two weeks in pH 7 solution at 4° C. UV/Vis spectropotentiometric titrations and protein film voltammetry identified 5 independent 1-electron reduction processes. Global analysis of the spectropotentiometric data also allowed determination of the extinction coefficient spectra for the 5 reduced ccNiR species. The characteristics of the individual extinction coefficient spectra suggest that, within each reduced species, the electrons are distributed amongst the various hemes, rather than being localized on specific heme centers. The purified ccNiR yielded good quality crystals, with which the 2.59 Å resolution structure was solved at room temperature using the Laue diffraction method. The structure is similar to that of E. coli ccNiR, except in the region where the enzyme interacts with its physiological electron donor (CymA in the case of S. oneidensis ccNiR, NrfB in the case of the E. coli protein). PMID:22382353
Effects of plant density on recombinant hemagglutinin yields in an Agrobacterium-mediated transient gene expression system using Nicotiana benthamiana plants.

PubMed

Fujiuchi, Naomichi; Matsuda, Ryo; Matoba, Nobuyuki; Fujiwara, Kazuhiro

2017-08-01

Agrobacterium-mediated transient expression systems enable plants to rapidly produce a wide range of recombinant proteins. To achieve economically feasible upstream production and downstream processing, it is beneficial to obtain high levels of two yield-related quantities of upstream production: recombinant protein content per fresh mass of harvested biomass (g gFM -1 ) and recombinant protein productivity per unit area-time (g m -2 /month). Here, we report that the density of Nicotiana benthamiana plants during upstream production had significant impacts on the yield-related quantities of recombinant hemagglutinin (HA). The two quantities were smaller at a high plant density of 400 plants m -2 than at a low plant density of 100 plants m -2 . The smaller quantities at the high plant density were attributed to: (i) a lower HA content in young leaves, which usually have high HA accumulation potentials; (ii) a lower biomass allocation to the young leaves; and (iii) a high area-time requirement for plants. Thus, plant density is a key factor for improving upstream production in Agrobacterium-mediated transient expression systems. Biotechnol. Bioeng. 2017;114: 1762-1770. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Establishing a high yielding streptomyces-based cell-free protein synthesis system.

PubMed

Li, Jian; Wang, He; Kwon, Yong-Chan; Jewett, Michael C

2017-06-01

Cell-free protein synthesis (CFPS) has emerged as a powerful platform for applied biotechnology and synthetic biology, with a range of applications in synthesizing proteins, evolving proteins, and prototyping genetic circuits. To expand the current CFPS repertoire, we report here the development and optimization of a Streptomyces-based CFPS system for the expression of GC-rich genes. By developing a streamlined crude extract preparation protocol and optimizing reaction conditions, we were able to achieve active enhanced green fluorescent protein (EGFP) yields of greater than 50 μg/mL with batch reactions lasting up to 3 h. By adopting a semi-continuous reaction format, the EGFP yield could be increased to 282 ± 8 μg/mL and the reaction time was extended to 48 h. Notably, our extract preparation procedures were robust to multiple Streptomyces lividans and Streptomyces coelicolor strains, although expression yields varied. We show that our optimized Streptomyces lividans system provides benefits when compared to an Escherichia coli-based CFPS system for increasing percent soluble protein expression for four Streptomyces-originated high GC-content genes that are involved in biosynthesis of the nonribosomal peptides tambromycin and valinomycin. Looking forward, we believe that our Streptomyces-based CFPS system will contribute significantly towards efforts to express complex natural product gene clusters (e.g., nonribosomal peptides and polyketides), providing a new avenue for obtaining and studying natural product biosynthesis pathways. Biotechnol. Bioeng. 2017;114: 1343-1353. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Increased bacterial cell density and recombinant protein yield using a commercial microbial cultivation system.

PubMed

Peck, Grantley R; Bowden, Timothy R; Shiell, Brian J; Michalski, Wojtek P

2014-01-01

EnBase (BioSilta, Finland) is a microbial cultivation system that replicates fed-batch systems through sustained release of glucose by enzymatic degradation of a polymeric substrate. Achievable bacterial cell densities and recombinant capripoxvirus protein expression levels, solubility, and antigenicity using the EnBase system were assessed. BL21-AI Escherichia coli expressing capripoxvirus proteins achieved up to eightfold higher cell densities when grown in EnBase media compared with standard media. Greater yields of capripoxvirus proteins were attained using EnBase media, either through increases in the amount of expressed protein per cell in conjunction with higher cell density or through the increase in cell density alone. Addition of EnBase booster enhanced protein yield for one of the proteins tested but reduced yield for the other. However, the amount of soluble forms of the capripoxvirus proteins tested was not different from that observed from cultures grown under standard conditions. Purified capripoxvirus proteins expressed using EnBase or standard media were assessed for their performance by enzyme-linked immunosorbent assay (ELISA) and were shown to be equally capable of specifically binding capripoxvirus antibodies.
Identification of Crowding Stress Tolerance Co-Expression Networks Involved in Sweet Corn Yield

PubMed Central

Choe, Eunsoo; Drnevich, Jenny; Williams, Martin M.

2016-01-01

Tolerance to crowding stress has played a crucial role in improving agronomic productivity in field corn; however, commercial sweet corn hybrids vary greatly in crowding stress tolerance. The objectives were to 1) explore transcriptional changes among sweet corn hybrids with differential yield under crowding stress, 2) identify relationships between phenotypic responses and gene expression patterns, and 3) identify groups of genes associated with yield and crowding stress tolerance. Under conditions of crowding stress, three high-yielding and three low-yielding sweet corn hybrids were grouped for transcriptional and phenotypic analyses. Transcriptional analyses identified from 372 to 859 common differentially expressed genes (DEGs) for each hybrid. Large gene expression pattern variation among hybrids and only 26 common DEGs across all hybrid comparisons were identified, suggesting each hybrid has a unique response to crowding stress. Over-represented biological functions of DEGs also differed among hybrids. Strong correlation was observed between: 1) modules with up-regulation in high-yielding hybrids and yield traits, and 2) modules with up-regulation in low-yielding hybrids and plant/ear traits. Modules linked with yield traits may be important crowding stress response mechanisms influencing crop yield. Functional analysis of the modules and common DEGs identified candidate crowding stress tolerant processes in photosynthesis, glycolysis, cell wall, carbohydrate/nitrogen metabolic process, chromatin, and transcription regulation. Moreover, these biological functions were greatly inter-connected, indicating the importance of improving the mechanisms as a network. PMID:26796516
Performance benchmarking of four cell-free protein expression systems.

PubMed

Gagoski, Dejan; Polinkovsky, Mark E; Mureev, Sergey; Kunert, Anne; Johnston, Wayne; Gambin, Yann; Alexandrov, Kirill

2016-02-01

Over the last half century, a range of cell-free protein expression systems based on pro- and eukaryotic organisms have been developed and have found a range of applications, from structural biology to directed protein evolution. While it is generally accepted that significant differences in performance among systems exist, there is a paucity of systematic experimental studies supporting this notion. Here, we took advantage of the species-independent translation initiation sequence to express and characterize 87 N-terminally GFP-tagged human cytosolic proteins of different sizes in E. coli, wheat germ (WGE), HeLa, and Leishmania-based (LTE) cell-free systems. Using a combination of single-molecule fluorescence spectroscopy, SDS-PAGE, and Western blot analysis, we assessed the expression yields, the fraction of full-length translation product, and aggregation propensity for each of these systems. Our results demonstrate that the E. coli system has the highest expression yields. However, we observe that high expression levels are accompanied by production of truncated species-particularly pronounced in the case of proteins larger than 70 kDa. Furthermore, proteins produced in the E. coli system display high aggregation propensity, with only 10% of tested proteins being produced in predominantly monodispersed form. The WGE system was the most productive among eukaryotic systems tested. Finally, HeLa and LTE show comparable protein yields that are considerably lower than the ones achieved in the E. coli and WGE systems. The protein products produced in the HeLa system display slightly higher integrity, whereas the LTE-produced proteins have the lowest aggregation propensity among the systems analyzed. The high quality of HeLa- and LTE-produced proteins enable their analysis without purification and make them suitable for analysis of multi-domain eukaryotic proteins. © 2015 Wiley Periodicals, Inc.
Gastrointestinal Spatiotemporal mRNA Expression of Ghrelin vs Growth Hormone Receptor and New Growth Yield Machine Learning Model Based on Perturbation Theory.

PubMed

Ran, Tao; Liu, Yong; Li, Hengzhi; Tang, Shaoxun; He, Zhixiong; Munteanu, Cristian R; González-Díaz, Humberto; Tan, Zhiliang; Zhou, Chuanshe

2016-07-27

The management of ruminant growth yield has economic importance. The current work presents a study of the spatiotemporal dynamic expression of Ghrelin and GHR at mRNA levels throughout the gastrointestinal tract (GIT) of kid goats under housing and grazing systems. The experiments show that the feeding system and age affected the expression of either Ghrelin or GHR with different mechanisms. Furthermore, the experimental data are used to build new Machine Learning models based on the Perturbation Theory, which can predict the effects of perturbations of Ghrelin and GHR mRNA expression on the growth yield. The models consider eight longitudinal GIT segments (rumen, abomasum, duodenum, jejunum, ileum, cecum, colon and rectum), seven time points (0, 7, 14, 28, 42, 56 and 70 d) and two feeding systems (Supplemental and Grazing feeding) as perturbations from the expected values of the growth yield. The best regression model was obtained using Random Forest, with the coefficient of determination R(2) of 0.781 for the test subset. The current results indicate that the non-linear regression model can accurately predict the growth yield and the key nodes during gastrointestinal development, which is helpful to optimize the feeding management strategies in ruminant production system.
Gastrointestinal Spatiotemporal mRNA Expression of Ghrelin vs Growth Hormone Receptor and New Growth Yield Machine Learning Model Based on Perturbation Theory

PubMed Central

Ran, Tao; Liu, Yong; Li, Hengzhi; Tang, Shaoxun; He, Zhixiong; Munteanu, Cristian R.; González-Díaz, Humberto; Tan, Zhiliang; Zhou, Chuanshe

2016-01-01

The management of ruminant growth yield has economic importance. The current work presents a study of the spatiotemporal dynamic expression of Ghrelin and GHR at mRNA levels throughout the gastrointestinal tract (GIT) of kid goats under housing and grazing systems. The experiments show that the feeding system and age affected the expression of either Ghrelin or GHR with different mechanisms. Furthermore, the experimental data are used to build new Machine Learning models based on the Perturbation Theory, which can predict the effects of perturbations of Ghrelin and GHR mRNA expression on the growth yield. The models consider eight longitudinal GIT segments (rumen, abomasum, duodenum, jejunum, ileum, cecum, colon and rectum), seven time points (0, 7, 14, 28, 42, 56 and 70 d) and two feeding systems (Supplemental and Grazing feeding) as perturbations from the expected values of the growth yield. The best regression model was obtained using Random Forest, with the coefficient of determination R2 of 0.781 for the test subset. The current results indicate that the non-linear regression model can accurately predict the growth yield and the key nodes during gastrointestinal development, which is helpful to optimize the feeding management strategies in ruminant production system. PMID:27460882
Expression of the Arabidopsis thaliana BBX32 gene in soybean increases grain yield.

PubMed

Preuss, Sasha B; Meister, Robert; Xu, Qingzhang; Urwin, Carl P; Tripodi, Federico A; Screen, Steven E; Anil, Veena S; Zhu, Shuquan; Morrell, James A; Liu, Grace; Ratcliffe, Oliver J; Reuber, T Lynne; Khanna, Rajnish; Goldman, Barry S; Bell, Erin; Ziegler, Todd E; McClerren, Amanda L; Ruff, Thomas G; Petracek, Marie E

2012-01-01

Crop yield is a highly complex quantitative trait. Historically, successful breeding for improved grain yield has led to crop plants with improved source capacity, altered plant architecture, and increased resistance to abiotic and biotic stresses. To date, transgenic approaches towards improving crop grain yield have primarily focused on protecting plants from herbicide, insects, or disease. In contrast, we have focused on identifying genes that, when expressed in soybean, improve the intrinsic ability of the plant to yield more. Through the large scale screening of candidate genes in transgenic soybean, we identified an Arabidopsis thaliana B-box domain gene (AtBBX32) that significantly increases soybean grain yield year after year in multiple transgenic events in multi-location field trials. In order to understand the underlying physiological changes that are associated with increased yield in transgenic soybean, we examined phenotypic differences in two AtBBX32-expressing lines and found increases in plant height and node, flower, pod, and seed number. We propose that these phenotypic changes are likely the result of changes in the timing of reproductive development in transgenic soybean that lead to the increased duration of the pod and seed development period. Consistent with the role of BBX32 in A. thaliana in regulating light signaling, we show that the constitutive expression of AtBBX32 in soybean alters the abundance of a subset of gene transcripts in the early morning hours. In particular, AtBBX32 alters transcript levels of the soybean clock genes GmTOC1 and LHY-CCA1-like2 (GmLCL2). We propose that through the expression of AtBBX32 and modulation of the abundance of circadian clock genes during the transition from dark to light, the timing of critical phases of reproductive development are altered. These findings demonstrate a specific role for AtBBX32 in modulating soybean development, and demonstrate the validity of expressing single genes in crops to
Novel Bioengineered Cassava Expressing an Archaeal Starch Degradation System and a Bacterial ADP-Glucose Pyrophosphorylase for Starch Self-Digestibility and Yield Increase.

PubMed

Ligaba-Osena, Ayalew; Jones, Jenna; Donkor, Emmanuel; Chandrayan, Sanjeev; Pole, Farris; Wu, Chang-Hao; Vieille, Claire; Adams, Michael W W; Hankoua, Bertrand B

2018-01-01

To address national and global low-carbon fuel targets, there is great interest in alternative plant species such as cassava ( Manihot esculenta ), which are high-yielding, resilient, and are easily converted to fuels using the existing technology. In this study the genes encoding hyperthermophilic archaeal starch-hydrolyzing enzymes, α-amylase and amylopullulanase from Pyrococcus furiosus and glucoamylase from Sulfolobus solfataricus , together with the gene encoding a modified ADP-glucose pyrophosphorylase ( glgC ) from Escherichia coli , were simultaneously expressed in cassava roots to enhance starch accumulation and its subsequent hydrolysis to sugar. A total of 13 multigene expressing transgenic lines were generated and characterized phenotypically and genotypically. Gene expression analysis using quantitative RT-PCR showed that the microbial genes are expressed in the transgenic roots. Multigene-expressing transgenic lines produced up to 60% more storage root yield than the non-transgenic control, likely due to glgC expression. Total protein extracted from the transgenic roots showed up to 10-fold higher starch-degrading activity in vitro than the protein extracted from the non-transgenic control. Interestingly, transgenic tubers released threefold more glucose than the non-transgenic control when incubated at 85°C for 21-h without exogenous application of thermostable enzymes, suggesting that the archaeal enzymes produced in planta maintain their activity and thermostability.
High-yield recombinant expression and purification of marginally soluble, short elastin-like polypeptides.

PubMed

Bahniuk, Markian S; Alshememry, Abdullah K; Unsworth, Larry D

2016-12-01

The protocol described here is designed as an extension of existing techniques for creating elastin-like polypeptides. It allows for the expression and purification of elastin-like polypeptide (ELP) constructs that are poorly expressed or have very low transition temperatures. DNA concatemerization has been modified to reduce issues caused by methylation sensitivity and inefficient cloning. Linearization of the modified expression vector has been altered to greatly increase cleavage efficiency. The purification regimen is based upon using denaturing metal affinity chromatography to fully solubilize and, if necessary, pre-concentrate the target peptide before purification by inverse temperature cycling (ITC). This protocol has been used to express multiple leucine-containing elastin-like polypeptides, with final yields of 250-660 mg per liter of cells, depending on the specific construct. This was considerably greater than previously reported yields for similar ELPs. Due to the relative hydrophobicity of the tested constructs, even compared with commonly employed ELPs, conventional methods would not have been able to be purify these peptides.
Maximizing RNA yield from archival renal tumors and optimizing gene expression analysis.

PubMed

Glenn, Sean T; Head, Karen L; Teh, Bin T; Gross, Kenneth W; Kim, Hyung L

2010-01-01

Formalin-fixed, paraffin-embedded tissues are widely available for gene expression analysis using TaqMan PCR. Five methods, including 4 commercial kits, for recovering RNA from paraffin-embedded renal tumor tissue were compared. The MasterPure kit from Epicentre produced the highest RNA yield. However, the difference in RNA yield between the kit from Epicenter and Invitrogen's TRIzol method was not significant. Using the top 3 RNA isolation methods, the manufacturers' protocols were modified to include an overnight Proteinase K digestion. Overnight protein digestion resulted in a significant increase in RNA yield. To optimize the reverse transcription reaction, conventional reverse transcription with random oligonucleotide primers was compared to reverse transcription using primers specific for genes of interest. Reverse transcription using gene-specific primers significantly increased the quantity of cDNA detectable by TaqMan PCR. Therefore, expression profiling of formalin-fixed, paraffin-embedded tissue using TaqMan qPCR can be optimized by using the MasterPure RNA isolation kit modified to include an overnight Proteinase K digestion and gene-specific primers during the reverse transcription.
Estimating yield gaps at the cropping system level.

PubMed

Guilpart, Nicolas; Grassini, Patricio; Sadras, Victor O; Timsina, Jagadish; Cassman, Kenneth G

2017-05-01

Yield gap analyses of individual crops have been used to estimate opportunities for increasing crop production at local to global scales, thus providing information crucial to food security. However, increases in crop production can also be achieved by improving cropping system yield through modification of spatial and temporal arrangement of individual crops. In this paper we define the cropping system yield potential as the output from the combination of crops that gives the highest energy yield per unit of land and time, and the cropping system yield gap as the difference between actual energy yield of an existing cropping system and the cropping system yield potential. Then, we provide a framework to identify alternative cropping systems which can be evaluated against the current ones. A proof-of-concept is provided with irrigated rice-maize systems at four locations in Bangladesh that represent a range of climatic conditions in that country. The proposed framework identified (i) realistic alternative cropping systems at each location, and (ii) two locations where expected improvements in crop production from changes in cropping intensity (number of crops per year) were 43% to 64% higher than from improving the management of individual crops within the current cropping systems. The proposed framework provides a tool to help assess food production capacity of new systems ( e.g. with increased cropping intensity) arising from climate change, and assess resource requirements (water and N) and associated environmental footprint per unit of land and production of these new systems. By expanding yield gap analysis from individual crops to the cropping system level and applying it to new systems, this framework could also be helpful to bridge the gap between yield gap analysis and cropping/farming system design.
Novel Bioengineered Cassava Expressing an Archaeal Starch Degradation System and a Bacterial ADP-Glucose Pyrophosphorylase for Starch Self-Digestibility and Yield Increase

PubMed Central

Ligaba-Osena, Ayalew; Jones, Jenna; Donkor, Emmanuel; Chandrayan, Sanjeev; Pole, Farris; Wu, Chang-Hao; Vieille, Claire; Adams, Michael W. W.; Hankoua, Bertrand B.

2018-01-01

To address national and global low-carbon fuel targets, there is great interest in alternative plant species such as cassava (Manihot esculenta), which are high-yielding, resilient, and are easily converted to fuels using the existing technology. In this study the genes encoding hyperthermophilic archaeal starch-hydrolyzing enzymes, α-amylase and amylopullulanase from Pyrococcus furiosus and glucoamylase from Sulfolobus solfataricus, together with the gene encoding a modified ADP-glucose pyrophosphorylase (glgC) from Escherichia coli, were simultaneously expressed in cassava roots to enhance starch accumulation and its subsequent hydrolysis to sugar. A total of 13 multigene expressing transgenic lines were generated and characterized phenotypically and genotypically. Gene expression analysis using quantitative RT-PCR showed that the microbial genes are expressed in the transgenic roots. Multigene-expressing transgenic lines produced up to 60% more storage root yield than the non-transgenic control, likely due to glgC expression. Total protein extracted from the transgenic roots showed up to 10-fold higher starch-degrading activity in vitro than the protein extracted from the non-transgenic control. Interestingly, transgenic tubers released threefold more glucose than the non-transgenic control when incubated at 85°C for 21-h without exogenous application of thermostable enzymes, suggesting that the archaeal enzymes produced in planta maintain their activity and thermostability. PMID:29541080
Estimating the potential refolding yield of recombinant proteins expressed as inclusion bodies.

PubMed

Ho, Jason G S; Middelberg, Anton P J

2004-09-05

Recombinant protein production in bacteria is efficient except that insoluble inclusion bodies form when some gene sequences are expressed. Such proteins must undergo renaturation, which is an inefficient process due to protein aggregation on dilution from concentrated denaturant. In this study, the protein-protein interactions of eight distinct inclusion-body proteins are quantified, in different solution conditions, by measurement of protein second virial coefficients (SVCs). Protein solubility is shown to decrease as the SVC is reduced (i.e., as protein interactions become more attractive). Plots of SVC versus denaturant concentration demonstrate two clear groupings of proteins: a more aggregative group and a group having higher SVC and better solubility. A correlation of the measured SVC with protein molecular weight and hydropathicity, that is able to predict which group each of the eight proteins falls into, is presented. The inclusion of additives known to inhibit aggregation during renaturation improves solubility and increases the SVC of both protein groups. Furthermore, an estimate of maximum refolding yield (or solubility) using high-performance liquid chromatography was obtained for each protein tested, under different environmental conditions, enabling a relationship between "yield" and SVC to be demonstrated. Combined, the results enable an approximate estimation of the maximum refolding yield that is attainable for each of the eight proteins examined, under a selected chemical environment. Although the correlations must be tested with a far larger set of protein sequences, this work represents a significant move beyond empirical approaches for optimizing renaturation conditions. The approach moves toward the ideal of predicting maximum refolding yield using simple bioinformatic metrics that can be estimated from the gene sequence. Such a capability could potentially "screen," in silico, those sequences suitable for expression in bacteria from those

The heterologous expression strategies of antimicrobial peptides in microbial systems.

PubMed

Deng, Ting; Ge, Haoran; He, Huahua; Liu, Yao; Zhai, Chao; Feng, Liang; Yi, Li

2017-12-01

Antimicrobial peptides (AMPs) consist of molecules acting on the defense systems of numerous organisms toward tumor and multiple pathogens, such as bacteria, fungi, viruses, and parasites. Compared to traditional antibiotics, AMPs are more stable and have lower propensity for developing resistance through functioning in the innate immune system, thus having important applications in the fields of medicine, food and so on. However, despite of their high economic values, the low yield and the cumbersome extraction process in AMPs production are problems that limit their industrial application and scientific research. To conquer these obstacles, optimized heterologous expression technologies were developed that could provide effective ways to increase the yield of AMPs. In this review, the research progress on heterologous expression of AMPs using Escherichia coli, Bacillus subtilis, Pichia pastoris and Saccharomyces cerevisiae as host cells was mainly summarized, which might guide the expression strategies of AMPs in these cells. Copyright © 2017 Elsevier Inc. All rights reserved.
Surprising yields with no-till cropping systems

USDA-ARS?s Scientific Manuscript database

Producers using no-till systems have found that crop yields often exceed their expectation based on nutrient and water supply. For example, corn yields 7% higher in a no-till system in central South Dakota than in a tilled system in eastern South Dakota. This is surprising because rainfall is 5 in...
Upper Limits for Power Yield in Thermal, Chemical, and Electrochemical Systems

NASA Astrophysics Data System (ADS)

Sieniutycz, Stanislaw

2010-03-01

We consider modeling and power optimization of energy converters, such as thermal, solar and chemical engines and fuel cells. Thermodynamic principles lead to expressions for converter's efficiency and generated power. Efficiency equations serve to solve the problems of upgrading or downgrading a resource. Power yield is a cumulative effect in a system consisting of a resource, engines, and an infinite bath. While optimization of steady state systems requires using the differential calculus and Lagrange multipliers, dynamic optimization involves variational calculus and dynamic programming. The primary result of static optimization is the upper limit of power, whereas that of dynamic optimization is a finite-rate counterpart of classical reversible work (exergy). The latter quantity depends on the end state coordinates and a dissipation index, h, which is the Hamiltonian of the problem of minimum entropy production. In reacting systems, an active part of chemical affinity constitutes a major component of the overall efficiency. The theory is also applied to fuel cells regarded as electrochemical flow engines. Enhanced bounds on power yield follow, which are stronger than those predicted by the reversible work potential.
Construction of two Lactococcus lactis expression vectors combining the Gateway and the NIsin Controlled Expression systems.

PubMed

Douillard, François P; Mahony, Jennifer; Campanacci, Valérie; Cambillau, Christian; van Sinderen, Douwe

2011-09-01

Over the last 10 years, the NIsin Controlled Expression (NICE) system has been extensively used in the food-grade bacterium Lactococcus lactis subsp. cremoris to produce homologous and heterologous proteins for academic and biotechnological purposes. Although various L. lactis molecular tools have been developed, no expression vectors harboring the popular Gateway recombination system are currently available for this widely used cloning host. In this study, we constructed two expression vectors that combine the NICE and the Gateway recombination systems and we tested their applicability by recombining and over-expressing genes encoding structural proteins of lactococcal phages Tuc2009 and TP901-1. Over-expressed phage proteins were analyzed by immunoblotting and purified by His-tag affinity chromatography with protein productions yielding 2.8-3.7 mg/l of culture. This therefore is the first description of L. lactis NICE expression vectors which integrate the Gateway cloning technology and which are suitable for the production of sufficient amounts of proteins to facilitate subsequent structural and functional analyses. Copyright © 2011 Elsevier Inc. All rights reserved.
Efficient expression systems for cysteine proteases of malaria parasites

PubMed Central

Sarduy, Emir Salas; de los A. Chávez Planes, María

2013-01-01

Papain-like cysteine proteases of malaria parasites are considered important chemotherapeutic targets or valuable models for the evaluation of drug candidates. Consequently, many of these enzymes have been cloned and expressed in Escherichia coli for their biochemical characterization. However, their expression has been problematic, showing low yield and leading to the formation of insoluble aggregates. Given that highly-productive expression systems are required for the high-throughput evaluation of inhibitors, we analyzed the existing expression systems to identify the causes of such apparent issues. We found that significant divergences in codon and nucleotide composition from host genes are the most probable cause of expression failure, and propose several strategies to overcome these limitations. Finally we predict that yeast hosts Saccharomyces cerevisiae and Pichia pastoris may be better suited than E. coli for the efficient expression of plasmodial genes, presumably leading to soluble and active products reproducing structural and functional characteristics of the natural enzymes. PMID:23018863
Differential gene expression at different stages of mesocarp development in high- and low-yielding oil palm.

PubMed

Wong, Yick Ching; Teh, Huey Fang; Mebus, Katharina; Ooi, Tony Eng Keong; Kwong, Qi Bin; Koo, Ka Loo; Ong, Chuang Kee; Mayes, Sean; Chew, Fook Tim; Appleton, David R; Kulaveerasingam, Harikrishna

2017-06-21

The oil yield trait of oil palm is expected to involve multiple genes, environmental influences and interactions. Many of the underlying mechanisms that contribute to oil yield are still poorly understood. In this study, we used a microarray approach to study the gene expression profiles of mesocarp tissue at different developmental stages, comparing genetically related high- and low- oil yielding palms to identify genes that contributed to the higher oil-yielding palm and might contribute to the wider genetic improvement of oil palm breeding populations. A total of 3412 (2001 annotated) gene candidates were found to be significantly differentially expressed between high- and low-yielding palms at at least one of the different stages of mesocarp development evaluated. Gene Ontologies (GO) enrichment analysis identified 28 significantly enriched GO terms, including regulation of transcription, fatty acid biosynthesis and metabolic processes. These differentially expressed genes comprise several transcription factors, such as, bHLH, Dof zinc finger proteins and MADS box proteins. Several genes involved in glycolysis, TCA, and fatty acid biosynthesis pathways were also found up-regulated in high-yielding oil palm, among them; pyruvate dehydrogenase E1 component Subunit Beta (PDH), ATP-citrate lyase, β- ketoacyl-ACP synthases I (KAS I), β- ketoacyl-ACP synthases III (KAS III) and ketoacyl-ACP reductase (KAR). Sucrose metabolism-related genes such as Invertase, Sucrose Synthase 2 and Sucrose Phosphatase 2 were found to be down-regulated in high-yielding oil palms, compared to the lower yield palms. Our findings indicate that a higher carbon flux (channeled through down-regulation of the Sucrose Synthase 2 pathway) was being utilized by up-regulated genes involved in glycolysis, TCA and fatty acid biosynthesis leading to enhanced oil production in the high-yielding oil palm. These findings are an important stepping stone to understand the processes that lead to
Expression of the hemagglutinin HA1 subunit of the equine influenza virus using a baculovirus expression system.

PubMed

Sguazza, Guillermo H; Fuentealba, Nadia A; Tizzano, Marco A; Galosi, Cecilia M; Pecoraro, Marcelo R

2013-01-01

Equine influenza virus is a leading cause of respiratory disease in horses worldwide. Disease prevention is by vaccination with inactivated whole virus vaccines. Most current influenza vaccines are generated in embryonated hens' eggs. Virions are harvested from allantoic fluid and chemically inactivated. Although this system has served well over the years, the use of eggs as the substrate for vaccine production has several well-recognized disadvantages (cost, egg supply, waste disposal and yield in eggs). The aim of this study was to evaluate a baculovirus system as a potential method for producing recombinant equine influenza hemagglutinin to be used as a vaccine. The hemagglutinin ectodomain (HA1 subunit) was cloned and expressed using a baculovirus expression vector. The expression was determined by SDS-PAGE and immunoblotting. A high yield, 20μg/ml of viral protein, was obtained from recombinant baculovirus-infected cells. The immune response in BALB/c mice was examined following rHA1 inoculation. Preliminary results show that recombinant hemagglutinin expressed from baculovirus elicits a strong antibody response in mice; therefore it could be used as an antigen for subunit vaccines and diagnostic tests. Copyright © 2013 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.
High-yield production of canine parvovirus virus-like particles in a baculovirus expression system.

PubMed

Jin, Hongli; Xia, Xiaohong; Liu, Bing; Fu, Yu; Chen, Xianping; Wang, Huihui; Xia, Zhenqiang

2016-03-01

An optimized VP2 gene from the current prevalent CPV strain (new CPV-2a) in China was expressed in a baculovirus expression system. It was found that the VP2 proteins assembled into virus-like particles (VLPs) with antigenic properties similar to those of natural CPV and with an especially high hemagglutination (HA) titer (1:2(20)). Dogs intramuscularly or orally immunized with VLPs produced antibodies against CPV with >1:80 hemagglutination inhibition (HI) units for at least 3 months. The CPV VLPs could be considered for use as a vaccine against CPV or as a platform for research on chimeric VLP vaccines against other diseases.
Engineering Extracellular Expression Systems in Escherichia coli Based on Transcriptome Analysis and Cell Growth State.

PubMed

Gao, Wen; Yin, Jun; Bao, Lichen; Wang, Qun; Hou, Shan; Yue, Yali; Yao, Wenbing; Gao, Xiangdong

2018-05-18

Escherichia coli extracellular expression systems have a number of advantages over other systems, such as lower pyrogen levels and a simple purification process. Various approaches, such as the generation of leaky mutants via chromosomal engineering, have been explored for this expression system. However, extracellular protein yields in leaky mutants are relatively low compared to that in intracellular expression systems and therefore need to be improved. In this work, we describe the construction, characterization, and mechanism of enhanced extracellular expression in Escherichia coli. On the basis of the localizations, functions, and transcription levels of cell envelope proteins, we systematically elucidated the effects of multiple gene deletions on cell growth and extracellular expression using modified CRISPR/Cas9-based genome editing and a FlAsH labeling assay. High extracellular yields of heterologous proteins of different sizes were obtained by screening multiple gene mutations. The enhancement of extracellular secretion was associated with the derepression of translation and translocation. This work utilized universal methods in the design of extracellular expression systems for genes not directly associated with protein synthesis that were used to generate strains with higher protein expression capability. We anticipate that extracellular expression systems may help to shed light on the poorly understood aspects of these secretion processes as well as to further assist in the construction of engineered prokaryotic cells for efficient extracellular production of heterologous proteins.
Biochemical properties and yields of diverse bacterial laccase-like multicopper oxidases expressed in Escherichia coli

PubMed Central

Ihssen, Julian; Reiss, Renate; Luchsinger, Ronny; Thöny-Meyer, Linda; Richter, Michael

2015-01-01

Laccases are multi-copper oxidases that oxidize a broad range of substrates at the expense of molecular oxygen, without any need for co-factor regeneration. These enzymes bear high potential for the sustainable synthesis of fine chemicals and the modification of (bio)polymers. Here we describe cloning and expression of five novel bacterial laccase-like multi copper oxidases (LMCOs) of diverse origin which were identified by homology searches in online databases. Activity yields under different expression conditions and temperature stabilities were compared to three previously described enzymes from Bacillus subtilis, Bacillus pumilus and Bacillus clausii. In almost all cases, a switch to oxygen-limited growth conditions after induction increased volumetric activity considerably. For proteins with predicted signal peptides for secretion, recombinant expression with and without signal sequence was investigated. Bacillus CotA-type LMCOs outperformed enzymes from Streptomyces and Gram-negative bacteria with respect to activity yields in Escherichia coli and application relevant biochemical properties. The novel Bacillus coagulans LMCO combined high activity yields in E. coli with unprecedented activity at strong alkaline pH and high storage stability, making it a promising candidate for further development. PMID:26068013
TaER Expression Is Associated with Transpiration Efficiency Traits and Yield in Bread Wheat

PubMed Central

Zheng, Jiacheng; Yang, Zhiyuan; Madgwick, Pippa J.; Carmo-Silva, Elizabete; Parry, Martin A. J.; Hu, Yin-Gang

2015-01-01

ERECTA encodes a receptor-like kinase and is proposed as a candidate for determining transpiration efficiency of plants. Two genes homologous to ERECTA in Arabidopsis were identified on chromosomes 6 (TaER2) and 7 (TaER1) of bread wheat (Triticum aestivum L.), with copies of each gene on the A, B and D genomes of wheat. Similar expression patterns were observed for TaER1 and TaER2 with relatively higher expression of TaER1 in flag leaves of wheat at heading (Z55) and grain-filling (Z73) stages. Significant variations were found in the expression levels of both TaER1 and TaER2 in the flag leaves at both growth stages among 48 diverse bread wheat varieties. Based on the expression of TaER1 and TaER2, the 48 wheat varieties could be classified into three groups having high (5 varieties), medium (27 varieties) and low (16 varieties) levels of TaER expression. Significant differences were also observed between the three groups varying for TaER expression for several transpiration efficiency (TE)- related traits, including stomatal density (SD), transpiration rate, photosynthetic rate (A), instant water use efficiency (WUEi) and carbon isotope discrimination (CID), and yield traits of biomass production plant-1 (BYPP) and grain yield plant-1 (GYPP). Correlation analysis revealed that the expression of TaER1 and TaER2 at the two growth stages was significantly and negatively associated with SD (P<0.01), transpiration rate (P<0.05) and CID (P<0.01), while significantly and positively correlated with flag leaf area (FLA, P<0.01), A (P<0.05), WUEi (P<0.05), BYPP (P<0.01) and GYPP (P<0.01), with stronger correlations for TaER1 than TaER2 and at grain-filling stage than at heading stage. These combined results suggested that TaER involved in development of transpiration efficiency -related traits and yield in bread wheat, implying a function for TaER in regulating leaf development of bread wheat and contributing to expression of these traits. Moreover, the results indicate
TaER Expression Is Associated with Transpiration Efficiency Traits and Yield in Bread Wheat.

PubMed

Zheng, Jiacheng; Yang, Zhiyuan; Madgwick, Pippa J; Carmo-Silva, Elizabete; Parry, Martin A J; Hu, Yin-Gang

2015-01-01

ERECTA encodes a receptor-like kinase and is proposed as a candidate for determining transpiration efficiency of plants. Two genes homologous to ERECTA in Arabidopsis were identified on chromosomes 6 (TaER2) and 7 (TaER1) of bread wheat (Triticum aestivum L.), with copies of each gene on the A, B and D genomes of wheat. Similar expression patterns were observed for TaER1 and TaER2 with relatively higher expression of TaER1 in flag leaves of wheat at heading (Z55) and grain-filling (Z73) stages. Significant variations were found in the expression levels of both TaER1 and TaER2 in the flag leaves at both growth stages among 48 diverse bread wheat varieties. Based on the expression of TaER1 and TaER2, the 48 wheat varieties could be classified into three groups having high (5 varieties), medium (27 varieties) and low (16 varieties) levels of TaER expression. Significant differences were also observed between the three groups varying for TaER expression for several transpiration efficiency (TE)- related traits, including stomatal density (SD), transpiration rate, photosynthetic rate (A), instant water use efficiency (WUEi) and carbon isotope discrimination (CID), and yield traits of biomass production plant-1 (BYPP) and grain yield plant-1 (GYPP). Correlation analysis revealed that the expression of TaER1 and TaER2 at the two growth stages was significantly and negatively associated with SD (P<0.01), transpiration rate (P<0.05) and CID (P<0.01), while significantly and positively correlated with flag leaf area (FLA, P<0.01), A (P<0.05), WUEi (P<0.05), BYPP (P<0.01) and GYPP (P<0.01), with stronger correlations for TaER1 than TaER2 and at grain-filling stage than at heading stage. These combined results suggested that TaER involved in development of transpiration efficiency -related traits and yield in bread wheat, implying a function for TaER in regulating leaf development of bread wheat and contributing to expression of these traits. Moreover, the results indicate
The growing impact of lyophilized cell-free protein expression systems

PubMed Central

Hunt, J. Porter; Yang, Seung Ook; Wilding, Kristen M.; Bundy, Bradley C.

2017-01-01

ABSTRACT Recently reported shelf-stable, on-demand protein synthesis platforms are enabling new possibilities in biotherapeutics, biosensing, biocatalysis, and high throughput protein expression. Lyophilized cell-free protein expression systems not only overcome cold-storage limitations, but also enable stockpiling for on-demand synthesis and completely sterilize the protein synthesis platform. Recently reported high-yield synthesis of cytotoxic protein Onconase from lyophilized E. coli extract preparations demonstrates the utility of lyophilized cell-free protein expression and its potential for creating on-demand biotherapeutics, vaccines, biosensors, biocatalysts, and high throughput protein synthesis. PMID:27791452
Development of a high yielding E. coli periplasmic expression system for the production of humanized Fab' fragments.

PubMed

Ellis, Mark; Patel, Pareshkumar; Edon, Marjory; Ramage, Walter; Dickinson, Robert; Humphreys, David P

2017-01-01

Humanized Fab' fragments may be produced in the periplasm of Escherichia coli but can be subject to degradation by host cell proteases. In order to increase Fab' yield and reduce proteolysis we developed periplasmic protease deficient strains of E. coli. These strains lacked the protease activity of Tsp, protease III and DegP. High cell density fermentations indicated Tsp deficient strains increased productivity two fold but this increase was accompanied by premature cell lysis soon after the induction of Fab' expression. To overcome the reduction in cell viability we introduced suppressor mutations into the spr gene. The mutations partially restored the wild type phenotype of the cells. Furthermore, we coexpressed a range of periplasmic chaperone proteins with the Fab', DsbC had the most significant impact, increasing humanized Fab' production during high cell density fermentation. When DsbC coexpression was combined with a Tsp deficient spr strain we observed an increase in yield and essentially restored "wild type" cell viability. We achieved a final periplasmic yield of over 2.4g/L (final cell density OD 600 105), 40 h post Fab' induction with minimal cell lysis.The data suggests that proteolysis, periplasm integrity, protein folding and disulphide bond formation are all potential limiting steps in the production of Fab' fragments in the periplasm of E. coli. In this body of work, we have addressed these limiting steps by utilizing stabilized protease deficient strains and chaperone coexpression. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:212-220, 2017. © 2016 American Institute of Chemical Engineers.
Vacuum transfer system increases sugar maple sap yield

Treesearch

Russell S. Walters

1978-01-01

Yields of sugar maple sap collected from three plastic pipeline systems by gravity, vacuum pump, and a vacuum pump with a transfer tank were compared during 2 years in northern Vermont. The transfer system yielded 27 percent more sap one year and 17 percent more the next year. Higher vacuum levels at the tapholes were observed in the transfer system.
Kinetics of lipogenic genes expression in milk purified mammary epithelial cells (MEC) across lactation and their correlation with milk and fat yield in buffalo.

PubMed

Yadav, Poonam; Kumar, Parveen; Mukesh, Manishi; Kataria, R S; Yadav, Anita; Mohanty, A K; Mishra, B P

2015-04-01

Expression patterns of lipogenic genes (LPL, ABCG2, ACSS2, ACACA, SCD, BDH, LIPIN1, SREBF1, PPARα and PPARγ) were studied in milk purified MEC across different stages of lactation (15, 30, 45, 60, 90, 120 and 240 days relative to parturition) in buffalo. PPARα was the most abundant gene while ABCG2 and ACSS2 had moderate level of expression; whereas expression of SREBF and PPARγ was very low. The expression patterns of some genes (BDH1, ACSS2, and LIPIN1) across lactation were positively correlated with milk yield while negatively correlated with fat yield. SCD also showed weak correlation with milk yield (p, 0.53) and fat yield (p, -0.47). On the other hand, expression pattern of ACACA was negatively correlated with milk yield (p, -0.88) and positively correlated with fat yield (p, 0.62). Strong correlation was observed between genes involved in de novo milk fat synthesis (BDH1, ACSS2, LIPIN2 and SCD) and milk yield. Copyright © 2015 Elsevier Ltd. All rights reserved.
Constitutive expression of cell wall invertase genes increases grain yield and starch content in maize.

PubMed

Li, Bei; Liu, Hua; Zhang, Yue; Kang, Tao; Zhang, Li; Tong, Jianhua; Xiao, Langtao; Zhang, Hongxia

2013-12-01

Grain size, number and starch content are important determinants of grain yield and quality. One of the most important biological processes that determine these components is the carbon partitioning during the early grain filling, which requires the function of cell wall invertase. Here, we showed the constitutive expression of cell wall invertase-encoding gene from Arabidopsis, rice (Oryza sativa) or maize (Zea mays), driven by the cauliflower mosaic virus (CaMV) 35S promoter, all increased cell wall invertase activities in different tissues and organs, including leaves and developing seeds, and substantially improved grain yield up to 145.3% in transgenic maize plants as compared to the wild-type plants, an effect that was reproduced in our 2-year field trials at different locations. The dramatically increased grain yield is due to the enlarged ears with both enhanced grain size and grain number. Constitutive expression of the invertase-encoding gene also increased total starch content up to 20% in the transgenic kernels. Our results suggest that cell wall invertase gene can be genetically engineered to improve both grain yield and grain quality in crop plants. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.
Techno-economic analysis of horseradish peroxidase production using a transient expression system in Nicotiana benthamiana.

PubMed

Walwyn, David Richard; Huddy, Suzanne M; Rybicki, Edward P

2015-01-01

Despite the advantages of plant-based transient expression systems relative to microbial or mammalian cell systems, the commercial production of recombinant proteins using plants has not yet been achieved to any significant extent. One of the challenges has been the lack of published data on the costs of manufacture for products other than biopharmaceuticals. In this study, we report on the techno-economic analysis of the production of a standard commercial enzyme, namely, horseradish peroxidase (HRP), using a transient expression system in Nicotiana benthamiana. Based on the proven plant yield of 240 mg HRP/kg biomass, a biomass productivity of 15-kg biomass/m(2)/year and a process yield of 54 % (mg HRP product/mg HRP in biomass), it is apparent that HRP can be manufactured economically via transient expression in plants in a large-scale facility (>5 kg HRP/year). At this level, the process is competitive versus the existing technology (extraction of the enzyme from horseradish), and the product is of comparable or improved activity, containing only the preferred isoenzyme C. Production scale, protein yield and biomass productivity are found to be the most important determinants of overall viability.
High-yield positron systems for linear colliders

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

Clendenin, J.E.

1989-04-01

Linear colliders, such as the SLC, are among those accelerators for which a high-yield positron source operating at the repetition rate of the accelerator is desired. The SLC, having electron energies up to 50 GeV, presents the possibility of generating positron bunches with useful charge even exceeding that of the initial electron bunch. The exact positron yield to be obtained depends on the particular capture, transport and damping system employed. Using 31 GeV electrons impinging on a W-type converter phase-space at the target to the acceptance of the capture rf section, the SLC source is capable of producing, for everymore » electron, up to two positrons within the acceptance of the positron damping ring. The design of this source and the performance of the positron system as built are described. Also, future prospects and limitations for high-yield positron systems are discussed. 11 refs., 5 figs., 3 tabs.« less
High-Yield Expression of M2e Peptide of Avian Influenza Virus H5N1 in Transgenic Duckweed Plants.

PubMed

Firsov, Aleksey; Tarasenko, Irina; Mitiouchkina, Tatiana; Ismailova, Natalya; Shaloiko, Lyubov; Vainstein, Alexander; Dolgov, Sergey

2015-07-01

Avian influenza is a major viral disease in poultry. Antigenic variation of this virus hinders vaccine development. However, the extracellular domain of the virus-encoded M2 protein (peptide M2e) is nearly invariant in all influenza A strains, enabling the development of a broad-range vaccine against them. Antigen expression in transgenic plants is becoming a popular alternative to classical expression methods. Here we expressed M2e from avian influenza virus A/chicken/Kurgan/5/2005(H5N1) in nuclear-transformed duckweed plants for further development of avian influenza vaccine. The N-terminal fragment of M2, including M2e, was selected for expression. The M2e DNA sequence fused in-frame to the 5' end of β-glucuronidase was cloned into pBI121 under the control of CaMV 35S promoter. The resulting plasmid was successfully used for duckweed transformation, and western analysis with anti-β-glucuronidase and anti-M2e antibodies confirmed accumulation of the target protein (M130) in 17 independent transgenic lines. Quantitative ELISA of crude protein extracts from these lines showed M130-β-glucuronidase accumulation ranging from 0.09-0.97 mg/g FW (0.12-1.96 % of total soluble protein), equivalent to yields of up to 40 μg M2e/g plant FW. This relatively high yield holds promise for the development of a duckweed-based expression system to produce an edible vaccine against avian influenza.

High-yield expression of recombinant soybean agglutinin in plants using transient and stable systems.

PubMed

Tremblay, Reynald; Feng, Mary; Menassa, Rima; Huner, Norman P A; Jevnikar, Anthony M; Ma, Shengwu

2011-04-01

Soybean agglutinin (SBA) is a specific N-acetylgalactosamine-binding plant lectin that can agglutinate a wide variety of cells. SBA has great potential for medical and biotechnology-focused applications, including screening and treatment of breast cancer, isolation of fetal cells from maternal blood for genetic screening, the possibility as a carrier system for oral drug delivery, and utilization as an affinity tag for high-quality purification of tagged proteins. The success of these applications, to a large degree, critically depends on the development of a highly efficient expression system for a source of recombinant SBA (rSBA). Here, we demonstrate the utility of transient and stable expression systems in Nicotiana benthamiana and potato, respectively, for the production of rSBA, with the transgenic protein accumulated to 4% of total soluble protein (TSP) in Nicotiana benthamiana leaves and 0.3% of TSP in potato tubers. Furthermore, we show that both plant-derived rSBAs retain their ability to induce the agglutination of red blood cells, are similarly glycosylated when compared with native SBA, retained their binding specificity for N-acetylgalactosamine, and were highly resistant to degradation in simulated gastric and intestinal fluids. Affinity column purification using N-acetylgalactosamine as a specific ligand resulted in high recovery and purity of rSBA. This work is the first step toward use of rSBA for various new applications, including the development of rSBA as a novel affinity tag for simplified purification of tagged proteins and as a new carrier molecule for delivery of oral drugs.
Animal component-free Agrobacterium tumefaciens cultivation media for better GMP-compliance increases biomass yield and pharmaceutical protein expression in Nicotiana benthamiana.

PubMed

Houdelet, Marcel; Galinski, Anna; Holland, Tanja; Wenzel, Kathrin; Schillberg, Stefan; Buyel, Johannes Felix

2017-04-01

Transient expression systems allow the rapid production of recombinant proteins in plants. Such systems can be scaled up to several hundred kilograms of biomass, making them suitable for the production of pharmaceutical proteins required at short notice, such as emergency vaccines. However, large-scale transient expression requires the production of recombinant Agrobacterium tumefaciens strains with the capacity for efficient gene transfer to plant cells. The complex media often used for the cultivation of this species typically include animal-derived ingredients that can contain human pathogens, thus conflicting with the requirements of good manufacturing practice (GMP). We replaced all the animal-derived components in yeast extract broth (YEB) cultivation medium with soybean peptone, and then used a design-of-experiments approach to optimize the medium composition, increasing the biomass yield while maintaining high levels of transient expression in subsequent infiltration experiments. The resulting plant peptone Agrobacterium medium (PAM) achieved a two-fold increase in OD 600 compared to YEB medium during a 4-L batch fermentation lasting 18 h. Furthermore, the yields of the monoclonal antibody 2G12 and the fluorescent protein DsRed were maintained when the cells were cultivated in PAM rather than YEB. We have thus demonstrated a simple, efficient and scalable method for medium optimization that reduces process time and costs. The final optimized medium for the cultivation of A. tumefaciens completely lacks animal-derived components, thus facilitating the GMP-compliant large-scale transient expression of recombinant proteins in plants. © 2017 The Authors. Biotechnology Journal published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Rapid high-yield expression of full-size IgG antibodies in plants coinfected with noncompeting viral vectors

PubMed Central

Giritch, Anatoli; Marillonnet, Sylvestre; Engler, Carola; van Eldik, Gerben; Botterman, Johan; Klimyuk, Victor; Gleba, Yuri

2006-01-01

Plant viral vectors allow expression of heterologous proteins at high yields, but so far, they have been unable to express heterooligomeric proteins efficiently. We describe here a rapid and indefinitely scalable process for high-level expression of functional full-size mAbs of the IgG class in plants. The process relies on synchronous coinfection and coreplication of two viral vectors, each expressing a separate antibody chain. The two vectors are derived from two different plant viruses that were found to be noncompeting. Unlike vectors derived from the same virus, noncompeting vectors effectively coexpress the heavy and light chains in the same cell throughout the plant body, resulting in yields of up to 0.5 g of assembled mAbs per kg of fresh-leaf biomass. This technology allows production of gram quantities of mAbs for research purposes in just several days, and the same protocol can be used on an industrial scale in situations requiring rapid response, such as pandemic or terrorism events. PMID:16973752
[Prokaryotic expression systems].

PubMed

Porowińska, Dorota; Wujak, Magdalena; Roszek, Katarzyna; Komoszyński, Michał

2013-03-01

For overproduction of recombinant proteins both eukaryotic and prokaryotic expression systems are used. Choosing the right system depends, among other things, on the growth rate and culture of host cells, level of the target gene expression and posttranslational processing of the synthesized protein. Regardless of the type of expression system, its basic elements are the vector and the expression host. The most widely used system for protein overproduction, both on a laboratory and industrial scale, is the prokaryotic system. This system is based primarily on the bacteria E. coli, although increasingly often Bacillus species are used. The prokaryotic system allows one to obtain large quantities of recombinant proteins in a short time. A simple and inexpensive bacterial cell culture and well-known mechanisms of transcription and translation facilitate the use of these microorganisms. The simplicity of genetic modifications and the availability of many bacterial mutants are additional advantages of the prokaryotic system. In this article we characterize the structural elements of prokaryotic expression vectors. Also strategies for preparation of the target protein gene that increase productivity, facilitate detection and purification of recombinant protein and provide its activity are discussed. Bacterial strains often used as host cells in expression systems as well as the potential location of heterologous proteins are characterized. Knowledge of the basic elements of the prokaryotic expression system allows for production of biologically active proteins in a short time and in satisfactory quantities.
Expression, purification and characterization of inactive and active forms of ERK2 from insect expression system.

PubMed

Yan, Kelly; Merritt, Hanne; Crawford, Kenneth; Pardee, Gwynn; Cheng, Jan Marie; Widger, Stephania; Hekmat-Nejad, Mohammad; Zaror, Isabel; Sim, Janet

2015-06-01

Extracellular signal-regulated kinase 2 (ERK2) is a serine/threonine protein kinase involved in many cellular programs, such as cell proliferation, differentiation, motility and programed cell-death. It is therefore considered an important target in the treatment of cancer. In an effort to support biochemical screening and small molecule drug discovery, we established a robust system to generate both inactive and active forms of ERK2 using insect expression system. We report here, for the first time, that inactive ERK2 can be expressed and purified with 100% homogeneity in the unphosphorylated form using insect system. This resulted in a significant 20-fold yield improvement compared to that previously reported using bacterial expression system. We also report a newly developed system to generate active ERK2 in insect cells through in vivo co-expression with a constitutively active MEK1 (S218D S222D). Isolated active ERK2 was confirmed to be doubly phosphorylated at the correct sites, T185 and Y187, in the activation loop of ERK2. Both ERK2 forms, inactive and active, were well characterized by biochemical activity assay for their kinase function. Inactive and active ERK2 were the two key reagents that enabled successful high through-put biochemical assay screen and structural drug discovery studies. Copyright © 2015 Elsevier Inc. All rights reserved.
EarthSat spring wheat yield system test 1975

NASA Technical Reports Server (NTRS)

1976-01-01

The results of an operational test of the EarthSat System during the period 1 June - 30 August 1975 over the spring wheat regions of North Dakota, South Dakota, and Minnesota are presented. The errors associated with each sub-element of the system during the operational test and the sensitivity of the complete system and each major functional sub-element of the system to the observed errors were evaluated. Evaluations and recommendations for future operational users of the system include: (1) changes in various system sub-elements, (2) changes in the yield model to affect improved accuracy, (3) changes in the number of geobased cells needed to develop an accurate aggregated yield estimate, (4) changes associated with the implementation of future operational satellites and data processing systems, and (5) detailed system documentation.
High yield expression and purification of equilibrative nucleoside transporter 7 (ENT7) from Arabidopsis thaliana.

PubMed

Girke, Christopher; Arutyunova, Elena; Syed, Maria; Traub, Michaela; Möhlmann, Torsten; Lemieux, M Joanne

2015-09-01

Equilibrative nucleoside transporters (ENTs) facilitate the import of nucleosides and their analogs into cells in a bidirectional, non-concentrative manner. However, in contrast to their name, most characterized plant ENTs act in a concentrative manner. A direct characterization of any ENT protein has been hindered due to difficulties in overexpression and obtaining pure recombinant protein. The equilibrative nucleoside transporter 7 from Arabidopsis thaliana (AtENT7) was expressed in Xenopus laevis oocytes to assess mechanism of substrate uptake. Recombinant protein fused to enhanced green fluorescent protein (eGFP) was expressed in Pichia pastoris to characterize its oligomeric state by gel filtration and substrate binding by microscale thermophoresis (MST). AtENT7 expressed in X. laevis oocytes works as a classic equilibrative transporter. The expression of AtENT7-eGFP in the P. pastoris system yielded milligram amounts of pure protein that exists as stable homodimers. The concentration dependent binding of purine and pyrimidine nucleosides to the purified recombinant protein, assessed by MST, confirmed that AtENT7-eGFP is properly folded. For the first time the binding of nucleobases was observed for AtENT7. The availability of pure recombinant AtENT7 will permit detailed kinetic and structural studies of this unique member of the ENT family and, given the functional similarity to mammalian ENTs, will serve as a good model for understanding the structural basis of translocation mechanism for the family. Copyright © 2015 Elsevier B.V. All rights reserved.
Ectopic expression of specific GA2 oxidase mutants promotes yield and stress tolerance in rice.

PubMed

Lo, Shuen-Fang; Ho, Tuan-Hua David; Liu, Yi-Lun; Jiang, Mirng-Jier; Hsieh, Kun-Ting; Chen, Ku-Ting; Yu, Lin-Chih; Lee, Miin-Huey; Chen, Chi-Yu; Huang, Tzu-Pi; Kojima, Mikiko; Sakakibara, Hitoshi; Chen, Liang-Jwu; Yu, Su-May

2017-07-01

A major challenge of modern agricultural biotechnology is the optimization of plant architecture for enhanced productivity, stress tolerance and water use efficiency (WUE). To optimize plant height and tillering that directly link to grain yield in cereals and are known to be tightly regulated by gibberellins (GAs), we attenuated the endogenous levels of GAs in rice via its degradation. GA 2-oxidase (GA2ox) is a key enzyme that inactivates endogenous GAs and their precursors. We identified three conserved domains in a unique class of C 20 GA2ox, GA2ox6, which is known to regulate the architecture and function of rice plants. We mutated nine specific amino acids in these conserved domains and observed a gradient of effects on plant height. Ectopic expression of some of these GA2ox6 mutants moderately lowered GA levels and reprogrammed transcriptional networks, leading to reduced plant height, more productive tillers, expanded root system, higher WUE and photosynthesis rate, and elevated abiotic and biotic stress tolerance in transgenic rice. Combinations of these beneficial traits conferred not only drought and disease tolerance but also increased grain yield by 10-30% in field trials. Our studies hold the promise of manipulating GA levels to substantially improve plant architecture, stress tolerance and grain yield in rice and possibly in other major crops. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.
Efficient production of Trastuzumab Fab antibody fragments in Brevibacillus choshinensis expression system.

PubMed

Mizukami, Makoto; Onishi, Hiromasa; Hanagata, Hiroshi; Miyauchi, Akira; Ito, Yuji; Tokunaga, Hiroko; Ishibashi, Matsujiro; Arakawa, Tsutomu; Tokunaga, Masao

2018-10-01

The Brevibacillus expression system has been successfully employed for the efficient productions of a variety of recombinant proteins, including enzymes, cytokines, antigens and antibody fragments. Here, we succeeded in secretory expression of Trastuzumab Fab antibody fragments using B. choshinensis/BIC (Brevibacillus in vivocloning) expression system. In the fed-batch high-density cell culture, recombinant Trastuzumab Fab with amino-terminal His-tag (His-BcFab) was secreted at high level, 1.25 g/liter, and Fab without His-tag (BcFab) at ∼145 mg/L of culture supernatant. His-BcFab and BcFab were purified to homogeneity using combination of conventional column chromatographies with a yield of 10-13%. This BcFab preparation exhibited native structure and functions evaluated by enzyme-linked immunosorbent assay, surface plasmon resonance, circular dichroism measurements and size exclusion chromatography. To our knowledge, this is the highest production of Fab antibody fragments in gram-positive bacterial expression/secretion systems. Copyright © 2018 Elsevier Inc. All rights reserved.
Yield gaps and yield relationships in US soybean production systems

USDA-ARS?s Scientific Manuscript database

The magnitude of yield gaps (YG) (potential yield – farmer yield) provides some indication of the prospects for increasing crop yield to meet the food demands of future populations. Quantile regression analysis was applied to county soybean [Glycine max (L.) Merrill] yields (1971 – 2011) from Kentuc...
An optimized expression vector for improving the yield of dengue virus-like particles from transfected insect cells.

PubMed

Charoensri, Nicha; Suphatrakul, Amporn; Sriburi, Rungtawan; Yasanga, Thippawan; Junjhon, Jiraphan; Keelapang, Poonsook; Utaipat, Utaiwan; Puttikhunt, Chunya; Kasinrerk, Watchara; Malasit, Prida; Sittisombut, Nopporn

2014-09-01

Recombinant virus-like particles (rVLPs) of flaviviruses are non-infectious particles released from cells expressing the envelope glycoproteins prM and E. Dengue virus rVLPs are recognized as a potential vaccine candidate, but large scale production of these particles is hindered by low yields and the occurrence of cytopathic effects. In an approach to improve the yield of rVLPs from transfected insect cells, several components of a dengue serotype 2 virus prM+E expression cassette were modified and the effect of these modifications was assessed during transient expression. Enhancement of extracellular rVLP levels by simultaneous substitutions of the prM signal peptide and the stem-anchor region of E with homologous cellular and viral counterparts, respectively, was further augmented by codon optimization. Extensive formation of multinucleated cells following transfection with the codon-optimized expression cassette was abrogated by introducing an E fusion loop mutation. This mutation also helped restore the extracellular E levels affected negatively by alteration of a charged residue at the pr-M junction, which was intended to promote maturation of rVLPs during export. Optimized expression cassettes generated in this multiple add-on modification approach should be useful in the generation of stably expressing clones and production of dengue virus rVLPs for immunogenicity studies. Copyright © 2014 Elsevier B.V. All rights reserved.
Pentopyranosyl Oligonucleotide Systems. Part 11: Systems with Shortened Backbones: D)-beta-Ribopyranosyl-(4 yields 3 )- and (L)-alpha - Lyxopyranosyl-(4 yields 3 )-oligonucleotides

NASA Technical Reports Server (NTRS)

Wippo, Harald; Reck, Folkert; Kudick, Rene; Ramaseshan, Mahesh; Ceulemans, Griet; Bolli, Martin; Krishnamurthy, Ramanarayanan; Eschenmoser, Albert

2001-01-01

The (L)-a-lyxopyranosyl-(4'yields 3')-oligonucleotide system-a member of a pentopyranosyl oligonucleotide family containing a shortened backbone-is capable of cooperative base-pairing and of cross-pairing with DNA and RNA. In contrast, corresponding (D)-beta-ribopyransoyl-(4' yields 3')-oligonucleotides do not show base-pairing under similar conditions. We conclude that oligonucleotide systems can violate the six-bonds-per-backbone-unit rule by having five bonds instead, if their vicinally bound phosphodiester bridges can assume an antiperiplanar conformation. An additional structural feature that seems relevant to the cross-pairing capability of the (L)-a-lyxopyranosyl-(4' yields 3')-oligonucleotide system is its (small) backbone/basepair axes inclination. An inclination which is similar to that in B-DNA seems to be a prerequisite for an oligonucleotide system s capability to cross-pair with DNA.
Solid-phase fermentation and juice expression systems for sweet sorghum

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

Bryan, W.L.; Monroe, G.E.; Caussariel, P.M.

1985-01-01

Two systems to recover fermented juice from variety M 81E sweet sorghum stalks that contained about 11% fermentable sugar were compared. (a) Stalks with leaves and tops removed were chopped and inoculated with 0.2% yeast in a forage harvester, stored under anaerobic conditions for 75 hours in insulated fermentors and pressed in a screw press to recover fermented juice (5-6% ethanol). (b) Mechanically harvested sweet sorghum billets (30 cm length) without leaves or seed heads were shredded and milled in a 3-roll mill; and bagasse was inoculated with 0.2% yeast, fermented for 100 h and pressed to recover fermented juicemore » (4 to 5% ethanol). Potential ethanol yields were 75% of theoretical for the forage harvest system and 78% for the shredder mill system, based on 95% of theoretical ethanol yield from juice expressed during milling and no loss of ethanol during fermentation, handling and pressing in the screw press. 20 references.« less
Bacterial cell-free expression technology to in vitro systems engineering and optimization.

PubMed

Caschera, Filippo

2017-06-01

Cell-free expression system is a technology for the synthesis of proteins in vitro . The system is a platform for several bioengineering projects, e.g. cell-free metabolic engineering, evolutionary design of experiments, and synthetic minimal cell construction. Bacterial cell-free protein synthesis system (CFPS) is a robust tool for synthetic biology. The bacteria lysate, the DNA, and the energy module, which are the three optimized sub-systems for in vitro protein synthesis, compose the integrated system. Currently, an optimized E. coli cell-free expression system can produce up to ∼2.3 mg/mL of a fluorescent reporter protein. Herein, I will describe the features of ATP-regeneration systems for in vitro protein synthesis, and I will present a machine-learning experiment for optimizing the protein yield of E. coli cell-free protein synthesis systems. Moreover, I will introduce experiments on the synthesis of a minimal cell using liposomes as dynamic containers, and E. coli cell-free expression system as biochemical platform for metabolism and gene expression. CFPS can be further integrated with other technologies for novel applications in environmental, medical and material science.
Yield improvement of heterologous peptides expressed in yps1-disrupted Saccharomyces cerevisiae strains.

PubMed

Egel-Mitani; Andersen; Diers; Hach; Thim; Hastrup; Vad

2000-06-01

Heterologous protein expression levels in Saccharomyces cerevisiae fermentations are highly dependent on the susceptibility to endogenous yeast proteases. Small peptides, such as glucagon and glucagon-like-peptides (GLP-1 and GLP-2), featuring an open structure are particularly accessible for proteolytic degradation during fermentation. Therefore, homogeneous products cannot be obtained. The most sensitive residues are found at basic amino acid residues in the peptide sequence. These heterologous peptides are degraded mainly by the YPS1-encoded aspartic protease, yapsin1, when produced in the yeast. In this article, distinct degradation products were analyzed by HPLC and mass spectrometry, and high yield of the heterologous peptide production has been achieved by the disruption of the YPS1 gene (previously called YAP3). By this technique, high yield continuous fermentation of glucagon in S. cerevisiae is now possible.
Expression of monellin in a food-grade delivery system in Saccharomyces cerevisiae.

PubMed

Liu, Jun; Yan, Da-zhong; Zhao, Sheng-jun

2015-10-01

Genetically modified (GM) foods have caused much controversy. Construction of a food-grade delivery system is a desirable technique with presumptive impact on industrial applications from the perspective of bio-safety. The aim of this study was to construct a food-grade delivery system for Saccharomyces cerevisiae and to study the expression of monellin from the berries of the West African forest plant Dioscoreophyllum cumminsii in this system. A food-grade system for S. cerevisiae was constructed based on ribosomal DNA (rDNA)-mediated homologous recombination to enable high-copy-number integration of the expression cassette inserted into the rDNA locus. A copper resistance gene (CUP1) was used as the selection marker for yeast transformation. Because variants of transformants containing different copy numbers at the CUP1 locus can be readily selected after growth in the presence of elevated copper levels, we suggest that this system would prove useful in the generation of tandemly iterated gene clusters. Using this food-grade system, a single-chain monellin gene was heterologously expressed. The yield of monellin reached a maximum of 675 mg L(-1) . This system harbors exclusively S. cerevisiae DNA with no antibiotic resistance genes, and it should therefore be appropriate for safe use in the food industry. Monellin was shown to be expressed in this food-grade delivery system. To our knowledge, this is the first report so far on expression of monellin in a food-grade expression system in S. cerevisiae. © 2014 Society of Chemical Industry.
Recombinants proteins for industrial uses: utilization of Pichia pastoris expression system

PubMed Central

Rabert, Claudia; Weinacker, Daniel; Pessoa, Adalberto; Farías, Jorge G.

2013-01-01

The innovation in industrial process with impact in the efficient production is the major challenge for actual industry. A high numerous of enzymes are utilized in at different level of process; the search for new alternatives with better characteristic has become a field of study of great interest, the recombinant protein achievement in a different host system is an alternative widely assessed for production of this. The microorganism Pichia pastoris has been used like a successful expression system in diverse areas, improved the yield and extraction-recovery of the product expressed. The reported of diverse authors in the production of enzymes with different application in industry is varied, in this review the different industry areas and the characteristic of the enzymes produced are detailed. PMID:24294221
Recombinants proteins for industrial uses: utilization of Pichia pastoris expression system.

PubMed

Rabert, Claudia; Weinacker, Daniel; Pessoa, Adalberto; Farías, Jorge G

2013-01-01

The innovation in industrial process with impact in the efficient production is the major challenge for actual industry. A high numerous of enzymes are utilized in at different level of process; the search for new alternatives with better characteristic has become a field of study of great interest, the recombinant protein achievement in a different host system is an alternative widely assessed for production of this. The microorganism Pichia pastoris has been used like a successful expression system in diverse areas, improved the yield and extraction-recovery of the product expressed. The reported of diverse authors in the production of enzymes with different application in industry is varied, in this review the different industry areas and the characteristic of the enzymes produced are detailed.
EarthSat spring wheat yield system test 1975, appendix 4

NASA Technical Reports Server (NTRS)

1976-01-01

A computer system is presented which processes meteorological data from both ground observations and meteorologic satellites to define plant weather aspects on a four time per day basis. Plant growth stages are calculated and soil moisture profiles are defined by the system. The EarthSat system assesses plant stress and prepares forecasts of end-of-year yields. The system was used to forecast spring wheat yields in the upper Great Plains states. Hardware and software documentation is provided.
Engineering Camelina sativa (L.) Crantz for enhanced oil and seed yields by combining diacylglycerol acyltransferase1 and glycerol-3-phosphate dehydrogenase expression.

PubMed

Chhikara, Sudesh; Abdullah, Hesham M; Akbari, Parisa; Schnell, Danny; Dhankher, Om Parkash

2018-05-01

Plant seed oil-based liquid transportation fuels (i.e., biodiesel and green diesel) have tremendous potential as environmentally, economically and technologically feasible alternatives to petroleum-derived fuels. Due to their nutritional and industrial importance, one of the major objectives is to increase the seed yield and oil production of oilseed crops via biotechnological approaches. Camelina sativa, an emerging oilseed crop, has been proposed as an ideal crop for biodiesel and bioproduct applications. Further increase in seed oil yield by increasing the flux of carbon from increased photosynthesis into triacylglycerol (TAG) synthesis will make this crop more profitable. To increase the oil yield, we engineered Camelina by co-expressing the Arabidopsis thaliana (L.) Heynh. diacylglycerol acyltransferase1 (DGAT1) and a yeast cytosolic glycerol-3-phosphate dehydrogenase (GPD1) genes under the control of seed-specific promoters. Plants co-expressing DGAT1 and GPD1 exhibited up to 13% higher seed oil content and up to 52% increase in seed mass compared to wild-type plants. Further, DGAT1- and GDP1-co-expressing lines showed significantly higher seed and oil yields on a dry weight basis than the wild-type controls or plants expressing DGAT1 and GPD1 alone. The oil harvest index (g oil per g total dry matter) for DGTA1- and GPD1-co-expressing lines was almost twofold higher as compared to wild type and the lines expressing DGAT1 and GPD1 alone. Therefore, combining the overexpression of TAG biosynthetic genes, DGAT1 and GPD1, appears to be a positive strategy to achieve a synergistic effect on the flux through the TAG synthesis pathway, and thereby further increase the oil yield. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Yield and yield gaps in central U.S. corn production systems

USDA-ARS?s Scientific Manuscript database

The magnitude of yield gaps (YG) (potential yield – farmer yield) provides some indication of the prospects for increasing crop yield. Quantile regression analysis was applied to county maize (Zea mays L.) yields (1972 – 2011) from Kentucky, Iowa and Nebraska (irrigated) (total of 115 counties) to e...
Maximal yields from multispecies fisheries systems: rules for systems with multiple trophic levels.

PubMed

Matsuda, Hiroyuki; Abrams, Peter A

2006-02-01

Increasing centralization of the control of fisheries combined with increased knowledge of food-web relationships is likely to lead to attempts to maximize economic yield from entire food webs. With the exception of predator-prey systems, we lack any analysis of the nature of such yield-maximizing strategies. We use simple food-web models to investigate the nature of yield- or profit-maximizing exploitation of communities including two types of three-species food webs and a variety of six-species systems with as many as five trophic levels. These models show that, for most webs, relatively few species are harvested at equilibrium and that a significant fraction of the species is lost from the web. These extinctions occur for two reasons: (1) indirect effects due to harvesting of species that had positive effects on the extinct species, and (2) intentional eradication of species that are not themselves valuable, but have negative effects on more valuable species. In most cases, the yield-maximizing harvest involves taking only species from one trophic level. In no case was an unharvested top predator part of the yield-maximizing strategy. Analyses reveal that the existence of direct density dependence in consumers has a large effect on the nature of the optimal harvest policy, typically resulting in harvest of a larger number of species. A constraint that all species must be retained in the system (a "constraint of biodiversity conservation") usually increases the number of species and trophic levels harvested at the yield-maximizing policy. The reduction in total yield caused by such a constraint is modest for most food webs but can be over 90% in some cases. Independent harvesting of species within the web can also cause extinctions but is less likely to do so.
On-line prediction of yield grade, longissimus muscle area, preliminary yield grade, adjusted preliminary yield grade, and marbling score using the MARC beef carcass image analysis system.

PubMed

Shackelford, S D; Wheeler, T L; Koohmaraie, M

2003-01-01

The present experiment was conducted to evaluate the ability of the U.S. Meat Animal Research Center's beef carcass image analysis system to predict calculated yield grade, longissimus muscle area, preliminary yield grade, adjusted preliminary yield grade, and marbling score under commercial beef processing conditions. In two commercial beef-processing facilities, image analysis was conducted on 800 carcasses on the beef-grading chain immediately after the conventional USDA beef quality and yield grades were applied. Carcasses were blocked by plant and observed calculated yield grade. The carcasses were then separated, with 400 carcasses assigned to a calibration data set that was used to develop regression equations, and the remaining 400 carcasses assigned to a prediction data set used to validate the regression equations. Prediction equations, which included image analysis variables and hot carcass weight, accounted for 90, 88, 90, 88, and 76% of the variation in calculated yield grade, longissimus muscle area, preliminary yield grade, adjusted preliminary yield grade, and marbling score, respectively, in the prediction data set. In comparison, the official USDA yield grade as applied by online graders accounted for 73% of the variation in calculated yield grade. The technology described herein could be used by the beef industry to more accurately determine beef yield grades; however, this system does not provide an accurate enough prediction of marbling score to be used without USDA grader interaction for USDA quality grading.
The effect of high concentrations of glufosinate ammonium on the yield components of transgenic spring wheat (Triticum aestivum L.) constitutively expressing the bar gene.

PubMed

Áy, Zoltán; Mihály, Róbert; Cserháti, Mátyás; Kótai, Éva; Pauk, János

2012-01-01

We present an experiment done on a bar(+) wheat line treated with 14 different concentrations of glufosinate ammonium-an effective component of nonselective herbicides-during seed germination in a closed experimental system. Yield components as number of spikes per plant, number of grains per spike, thousand kernel weight, and yield per plant were thoroughly analysed and statistically evaluated after harvesting. We found that a concentration of glufosinate ammonium 5000 times the lethal dose was not enough to inhibit the germination of transgenic plants expressing the bar gene. Extremely high concentrations of glufosinate ammonium caused a bushy phenotype, significantly lower numbers of grains per spike, and thousand kernel weights. Concerning the productivity, we observed that concentrations of glufosinate ammonium 64 times the lethal dose did not lead to yield depression. Our results draw attention to the possibilities implied in the transgenic approaches.
[Expression of human-mouse chimeric antibody directed against Chikungunya virus with site-specific integration system].

PubMed

Li, Jian-min; Chen, Wei; Jia, Xiu-jie; An, Xiao-ping; Li, Bing; Fan, Ying-ru; Tong, Yi-gang

2005-05-01

To obtain CHO/dhfr(-) cells line with integrated FRT sequence in the chromosome transcription active site and to express human-mouse chimeric antibody directed against Chikungunya Virus by using the cell line. The fusion gene of FRT and HBsAg was constructed by PCR and cloned into the MCS of pCI-neo to construct pCI-FRT-HBsAg. The pCI-FRT-HBsAg was transfected into CHO/dhfr(-) cells and cell clones with high expression of HBsAg were screened by detecting the amount of HBsAg with ELISA. A CHO cell clone with the highest expression was chosen and named as CHO/dhfr(-) FRT(+). pAFRT HFLF, a expression plasmid of chimeric antibody with RFT sequence was transfected into CHO/dhfr(-) FRT(+) cells and cell clones with high expression of the chimeric antibody were screened by increasing concentration of MTX. A CHO cell clone with high expression of the chimeric antibody was cultured in large scale and supernatant was collected from which the chimeric antibody was purified. The purified chimeric antibody was analyzed by SDS-PAGE, Western blot and IFA. A CHO/dhfr(-) cells line with integrated FRT sequence in the chromosome transcription active site was obtained successfully. A cell clone with yield of 5 mg/L of chimeric antibody was obtained, as compared with routine CHO cell expression system with a yield of 2 mg/L. A cell line with integrated FRT sequence in the chromosome transcription active site was obtained and with it human-mouse chimeric antibody directed against Chikungunya virus was expressed. This system lays a solid foundation which can be used for expressing antibodies and other proteins.
Antimicrobial peptide production and plant-based expression systems for medical and agricultural biotechnology.

PubMed

Holaskova, Edita; Galuszka, Petr; Frebort, Ivo; Oz, M Tufan

2015-11-01

Antimicrobial peptides (AMPs) are vital components of the innate immune system of nearly all living organisms. They generally act in the first line of defense against various pathogenic bacteria, parasites, enveloped viruses and fungi. These low molecular mass peptides are considered prospective therapeutic agents due to their broad-spectrum rapid activity, low cytotoxicity to mammalian cells and unique mode of action which hinders emergence of pathogen resistance. In addition to medical use, AMPs can also be employed for development of innovative approaches for plant protection in agriculture. Conferred disease resistance by AMPs might help us surmount losses in yield, quality and safety of agricultural products due to plant pathogens. Heterologous expression in plant-based systems, also called plant molecular farming, offers cost-effective large-scale production which is regarded as one of the most important factors for clinical or agricultural use of AMPs. This review presents various types of AMPs as well as plant-based platforms ranging from cell suspensions to whole plants employed for peptide production. Although AMP production in plants holds great promises for medicine and agriculture, specific technical limitations regarding product yield, function and stability still remain. Additionally, establishment of particular stable expression systems employing plants or plant tissues generally requires extended time scale for platform development compared to certain other heterologous systems. Therefore, fast and promising tools for evaluation of plant-based expression strategies and assessment of function and stability of the heterologously produced AMPs are critical for molecular farming and plant protection. Copyright © 2015 Elsevier Inc. All rights reserved.
Greenhouse tomato limited cluster production systems: crop management practices affect yield

NASA Technical Reports Server (NTRS)

Logendra, L. S.; Gianfagna, T. J.; Specca, D. R.; Janes, H. W.

2001-01-01

Limited-cluster production systems may be a useful strategy to increase crop production and profitability for the greenhouse tomato (Lycopersicon esculentum Mill). In this study, using an ebb-and-flood hydroponics system, we modified plant architecture and spacing and determined the effects on fruit yield and harvest index at two light levels. Single-cluster plants pruned to allow two leaves above the cluster had 25% higher fruit yields than did plants pruned directly above the cluster; this was due to an increase in fruit weight, not fruit number. Both fruit yield and harvest index were greater for all single-cluster plants at the higher light level because of increases in both fruit weight and fruit number. Fruit yield for two-cluster plants was 30% to 40% higher than for single-cluster plants, and there was little difference in the dates or length of the harvest period. Fruit yield for three-cluster plants was not significantly different from that of two-cluster plants; moreover, the harvest period was delayed by 5 days. Plant density (5.5, 7.4, 9.2 plants/m2) affected fruit yield/plant, but not fruit yield/unit area. Given the higher costs for materials and labor associated with higher plant densities, a two-cluster crop at 5.5 plants/m2 with two leaves above the cluster was the best of the production system strategies tested.
Methods for high yield production of terpenes

DOEpatents

Kutchan, Toni; Higashi, Yasuhiro; Feng, Xiaohong

2017-01-03

Provided are enhanced high yield production systems for producing terpenes in plants via the expression of fusion proteins comprising various combinations of geranyl diphosphate synthase large and small subunits and limonene synthases. Also provided are engineered oilseed plants that accumulate monoterpene and sesquiterpene hydrocarbons in their seeds, as well as methods for producing such plants, providing a system for rapidly engineering oilseed crop production platforms for terpene-based biofuels.
Expression of Lectins in Heterologous Systems

PubMed Central

Martínez-Alarcón, Dania; Blanco-Labra, Alejandro

2018-01-01

Lectins are proteins that have the ability to recognize and bind in a reversible and specific way to free carbohydrates or glycoconjugates of cell membranes. For these reasons, they have been extensively used in a wide range of industrial and pharmacological applications. Currently, there is great interest in their production on a large scale. Unfortunately, conventional techniques do not provide the appropriate platform for this purpose and therefore, the heterologous production of lectins in different organisms has become the preferred method in many cases. Such systems have the advantage of providing better yields as well as more homogeneous and better-defined properties for the resultant products. However, an inappropriate choice of the expression system can cause important structural alterations that have repercussions on their biological activity since the specificity may lay in their post-translational processing, which depends largely on the producing organism. The present review aims to examine the most representative studies in the area, exposing the four most frequently used systems (bacteria, yeasts, plants and animal cells), with the intention of providing the necessary information to determine the strategy to follow in each case as well as their respective advantages and disadvantages. PMID:29466298
Development of a telemetry and yield-mapping system of olive harvester.

PubMed

Castillo-Ruiz, Francisco J; Pérez-Ruiz, Manuel; Blanco-Roldán, Gregorio L; Gil-Ribes, Jesús A; Agüera, Juan

2015-02-10

Sensors, communication systems and geo-reference units are required to achieve an optimized management of agricultural inputs with respect to the economic and environmental aspects of olive groves. In this study, three commercial olive harvesters were tracked during two harvesting seasons in Spain and Chile using remote and autonomous equipment that was developed to determine their time efficiency and effective based on canopy shaking for fruit detachment. These harvesters work in intensive/high-density (HD) and super-high-density (SHD) olive orchards. A GNSS (Global Navigation Satellite System) and GSM (Global System for Mobile Communications) device was installed to track these harvesters. The GNSS receiver did not affect the driver's work schedule. Time elements methodology was adapted to the remote data acquisition system. The effective field capacity and field efficiency were investigated. In addition, the field shape, row length, angle between headland alley and row, and row alley width were measured to determinate the optimum orchard design parameters value. The SHD olive harvester showed significant lower effective field capacity values when alley width was less than 4 m. In addition, a yield monitor was developed and installed on a traditional olive harvester to obtain a yield map from the harvested area. The hedge straddle harvester stood out for its highly effective field capacity; nevertheless, a higher field efficiency was provided by a non-integral lateral canopy shaker. All of the measured orchard parameters have influenced machinery yields, whether effective field capacity or field efficiency. A saving of 40% in effective field capacity was achieved with a reduction from 4 m or higher to 3.5 m in alley width for SHD olive harvester. A yield map was plotted using data that were acquired by a yield monitor, reflecting the yield gradient in spite of the larger differences between tree yields.
Development of a Telemetry and Yield-Mapping System of Olive Harvester

PubMed Central

Castillo-Ruiz, Francisco J.; Pérez-Ruiz, Manuel; Blanco-Roldán, Gregorio L.; Gil-Ribes, Jesús A.; Agüera, Juan

2015-01-01

Sensors, communication systems and geo-reference units are required to achieve an optimized management of agricultural inputs with respect to the economic and environmental aspects of olive groves. In this study, three commercial olive harvesters were tracked during two harvesting seasons in Spain and Chile using remote and autonomous equipment that was developed to determine their time efficiency and effective based on canopy shaking for fruit detachment. These harvesters work in intensive/high-density (HD) and super-high-density (SHD) olive orchards. A GNSS (Global Navigation Satellite System) and GSM (Global System for Mobile Communications) device was installed to track these harvesters. The GNSS receiver did not affect the driver’s work schedule. Time elements methodology was adapted to the remote data acquisition system. The effective field capacity and field efficiency were investigated. In addition, the field shape, row length, angle between headland alley and row, and row alley width were measured to determinate the optimum orchard design parameters value. The SHD olive harvester showed significant lower effective field capacity values when alley width was less than 4 m. In addition, a yield monitor was developed and installed on a traditional olive harvester to obtain a yield map from the harvested area. The hedge straddle harvester stood out for its highly effective field capacity; nevertheless, a higher field efficiency was provided by a non-integral lateral canopy shaker. All of the measured orchard parameters have influenced machinery yields, whether effective field capacity or field efficiency. A saving of 40% in effective field capacity was achieved with a reduction from 4 m or higher to 3.5 m in alley width for SHD olive harvester. A yield map was plotted using data that were acquired by a yield monitor, reflecting the yield gradient in spite of the larger differences between tree yields. PMID:25675283
High-Yield, Zero-Leakage Expression System with a Translational Switch Using Site-Specific Unnatural Amino Acid Incorporation

PubMed Central

Minaba, Masaomi

2014-01-01

Synthetic biologists construct complex biological circuits by combinations of various genetic parts. Many genetic parts that are orthogonal to one another and are independent of existing cellular processes would be ideal for use in synthetic biology. However, our toolbox is still limited with respect to the bacterium Escherichia coli, which is important for both research and industrial use. The site-specific incorporation of unnatural amino acids is a technique that incorporates unnatural amino acids into proteins using a modified exogenous aminoacyl-tRNA synthetase/tRNA pair that is orthogonal to any native pairs in a host and is independent from other cellular functions. Focusing on the orthogonality and independency that are suitable for the genetic parts, we designed novel AND gate and translational switches using the unnatural amino acid 3-iodo-l-tyrosine incorporation system in E. coli. A translational switch was turned on after addition of 3-iodo-l-tyrosine in the culture medium within minutes and allowed tuning of switchability and translational efficiency. As an application, we also constructed a gene expression system that produced large amounts of proteins under induction conditions and exhibited zero-leakage expression under repression conditions. Similar translational switches are expected to be applicable also for eukaryotes such as yeasts, nematodes, insects, mammalian cells, and plants. PMID:24375139
Venus Express Chemical Propulsion System - The Mars Express Legacy

NASA Astrophysics Data System (ADS)

Hunter, C. J.

2004-10-01

ESA's ambition of inter-planetary exploration using a fast-track low cost industrial programme was well achieved with Mars Express. Reusing the platform architecture for the service module and specifically the Propulsion system enabled Venus Express to benefit from several lessons learnt from the Mars Express experience. Using all existing components qualified for previous programmes, many of them commercial telecommunication spacecraft programmes with components available from stock, an industrial organisation familiar from Mars Express was able to compress the schedule to make the November 2005 launch window a realistic target. While initial inspection of the CPS schematic indicates a modified Eurostar type architecture, - a similar system using some Eurostar components - would be a fairer description. The use of many parts of the system on arrival at the destination (Mars or Venus in this case) is a departure from the usual mode of operation, where many components are used during the initial few weeks of GTO or GEO. The system modifications over the basic Eurostar system have catered for this in terms of reliability contingencies by replacing components, or providing different levels of test capability or isolation in flight. This paper aims to provide an introduction to the system, address the evolution from Eurostar, and provide an initial assessment of the success of these modifications using the Mars Express experience, and how measures have been adopted specifically for Venus Express.
Specific yield: compilation of specific yields for various materials

USGS Publications Warehouse

Johnson, A.I.

1967-01-01

Specific yield is defined as the ratio of (1) the volume of water that a saturated rock or soil will yield by gravity to (2) the total volume of the rock or soft. Specific yield is usually expressed as a percentage. The value is not definitive, because the quantity of water that will drain by gravity depends on variables such as duration of drainage, temperature, mineral composition of the water, and various physical characteristics of the rock or soil under consideration. Values of specific yields nevertheless offer a convenient means by which hydrologists can estimate the water-yielding capacities of earth materials and, as such, are very useful in hydrologic studies. The present report consists mostly of direct or modified quotations from many selected reports that present and evaluate methods for determining specific yield, limitations of those methods, and results of the determinations made on a wide variety of rock and soil materials. Although no particular values are recommended in this report, a table summarizes values of specific yield, and their averages, determined for 10 rock textures. The following is an abstract of the table. [Table
Development and application of a T7 RNA polymerase-dependent expression system for antibiotic production improvement in Streptomyces.

PubMed

Wei, Junhong; Tian, Jinjin; Pan, Guoqing; Xie, Jie; Bao, Jialing; Zhou, Zeyang

2017-06-01

To develop a reliable and easy to use expression system for antibiotic production improvement of Streptomyces. A two-compound T7 RNA polymerase-dependent gene expression system was developed to fulfill this demand. In this system, the T7 RNA polymerase coding sequence was optimized based on the codon usage of Streptomyces coelicolor. To evaluate the functionality of this system, we constructed an activator gene overexpression strain for enhancement of actinorhodin production. By overexpression of the positive regulator actII-ORF4 with this system, the maximum actinorhodin yield of engineered strain was 15-fold higher and the fermentation time was decreased by 48 h. The modified two-compound T7 expression system improves both antibiotic production and accelerates the fermentation process in Streptomyces. This provides a general and useful strategy for strain improvement of important antibiotic producing Streptomyces strains.
Genome-Wide Identification of Differentially Expressed Genes Associated with the High Yielding of Oleoresin in Secondary Xylem of Masson Pine (Pinus massoniana Lamb) by Transcriptomic Analysis

PubMed Central

Liu, Qinghua; Zhou, Zhichun; Wei, Yongcheng; Shen, Danyu; Feng, Zhongping; Hong, Shanping

2015-01-01

Masson pine is an important timber and resource for oleoresin in South China. Increasing yield of oleoresin in stems can raise economic benefits and enhance the resistance to bark beetles. However, the genetic mechanisms for regulating the yield of oleoresin were still unknown. Here, high-throughput sequencing technology was used to investigate the transcriptome and compare the gene expression profiles of high and low oleoresin-yielding genotypes. A total of 40,690,540 reads were obtained and assembled into 137,499 transcripts from the secondary xylem tissues. We identified 84,842 candidate unigenes based on sequence annotation using various databases and 96 unigenes were candidates for terpenoid backbone biosynthesis in pine. By comparing the expression profiles of high and low oleoresin-yielding genotypes, 649 differentially expressed genes (DEGs) were identified. GO enrichment analysis of DEGs revealed that multiple pathways were related to high yield of oleoresin. Nine candidate genes were validated by QPCR analysis. Among them, the candidate genes encoding geranylgeranyl diphosphate synthase (GGPS) and (-)-alpha/beta-pinene synthase were up-regulated in the high oleoresin-yielding genotype, while tricyclene synthase revealed lower expression level, which was in good agreement with the GC/MS result. In addition, DEG encoding ABC transporters, pathogenesis-related proteins (PR5 and PR9), phosphomethylpyrimidine synthase, non-specific lipid-transfer protein-like protein and ethylene responsive transcription factors (ERFs) were also confirmed to be critical for the biosynthesis of oleoresin. The next-generation sequencing strategy used in this study has proven to be a powerful means for analyzing transcriptome variation related to the yield of oleoresin in masson pine. The candidate genes encoding GGPS, (-)-alpha/beta-pinene, tricyclene synthase, ABC transporters, non-specific lipid-transfer protein-like protein, phosphomethylpyrimidine synthase, ERFs and pathogen
Expression and bioactivity of human α-fetoprotein in a Bac-to-Bac system

PubMed Central

Lin, Bo; Liu, Kun; Wang, Wenting; Li, Wei; Dong, Xu; Chen, Yi; Lu, Yan; Guo, Junli; Li, Mengsen

2016-01-01

α-fetoprotein (AFP) is an early serum growth factor in foetal embryonic development and hepatic oncogenesis. A growing number of investigations of AFP as a tumour-specific biomarker have concluded that AFP is an important target for cancer treatment. AFP also plays an immunomodulatory role in the treatment of several autoimmune diseases, such as rheumatoid arthritis, multiple sclerosis, myasthenia gravis and thyroiditis. In an effort to support biochemical screening and drug design and discovery, we attempted to express and purify human AFP in a Bac-to-Bac system. Two key factors affecting the expression of recombinant human AFP (R-AFP), namely the infectious baculovirus inoculum volume and the culturing time post-infection, were optimized to maximize the yield. We achieved a high yield of approximately 1.5 mg/l of harvested medium with a 72–96 h incubation period after infection and an inoculum volume ratio of 1:100. We also assessed the role of R-AFP in the proliferation of the human liver cancer cell line Bel 7402, and the results indicated that R-AFP promoted the growth of hepatoma cells. We concluded that this method can produce high yields of R-AFP, which can be used for studies related to AFP. PMID:27913752
Expression and bioactivity of human α-fetoprotein in a Bac-to-Bac system.

PubMed

Lin, Bo; Liu, Kun; Wang, Wenting; Li, Wei; Dong, Xu; Chen, Yi; Lu, Yan; Guo, Junli; Zhu, Mingyue; Li, Mengsen

2017-02-28

α-fetoprotein (AFP) is an early serum growth factor in foetal embryonic development and hepatic oncogenesis. A growing number of investigations of AFP as a tumour-specific biomarker have concluded that AFP is an important target for cancer treatment. AFP also plays an immunomodulatory role in the treatment of several autoimmune diseases, such as rheumatoid arthritis, multiple sclerosis, myasthenia gravis and thyroiditis. In an effort to support biochemical screening and drug design and discovery, we attempted to express and purify human AFP in a Bac-to-Bac system. Two key factors affecting the expression of recombinant human AFP (R-AFP), namely the infectious baculovirus inoculum volume and the culturing time post-infection, were optimized to maximize the yield. We achieved a high yield of approximately 1.5 mg/l of harvested medium with a 72-96 h incubation period after infection and an inoculum volume ratio of 1:100. We also assessed the role of R-AFP in the proliferation of the human liver cancer cell line Bel 7402, and the results indicated that R-AFP promoted the growth of hepatoma cells. We concluded that this method can produce high yields of R-AFP, which can be used for studies related to AFP. © 2017 The Author(s).
Improvement of enzymatic saccharification yield in Arabidopsis thaliana by ectopic expression of the rice SUB1A-1 transcription factor

PubMed Central

Núñez-López, Lizeth; Aguirre-Cruz, Andrés

2015-01-01

Saccharification of polysaccharides releases monosaccharides that can be used by ethanol-producing microorganisms in biofuel production. To improve plant biomass as a raw material for saccharification, factors controlling the accumulation and structure of carbohydrates must be identified. Rice SUB1A-1 is a transcription factor that represses the turnover of starch and postpones energy-consuming growth processes under submergence stress. Arabidopsis was employed to test if heterologous expression of SUB1A-1 or SUB1C-1 (a related gene) can be used to improve saccharification. Cellulolytic and amylolytic enzymatic treatments confirmed that SUB1A-1 transgenics had better saccharification yield than wild-type (Col-0), mainly from accumulated starch. This improved saccharification yield was developmentally controlled; when compared to Col-0, young transgenic vegetative plants yielded 200–300% more glucose, adult vegetative plants yielded 40–90% more glucose and plants in reproductive stage had no difference in yield. We measured photosynthetic parameters, starch granule microstructure, and transcript abundance of genes involved in starch degradation (SEX4, GWD1), juvenile transition (SPL3-5) and meristematic identity (FUL, SOC1) but found no differences to Col-0, indicating that starch accumulation may be controlled by down-regulation of CONSTANS and FLOWERING LOCUS T by SUB1A-1 as previously reported. SUB1A-1 transgenics also offered less resistance to deformation than wild-type concomitant to up-regulation of AtEXP2 expansin and BGL2 glucan-1,3,-beta-glucosidase. We conclude that heterologous SUB1A-1 expression can improve saccharification yield and softness, two traits needed in bioethanol production. PMID:25780769
The yield and decay coefficients of exoelectrogenic bacteria in bioelectrochemical systems.

PubMed

Wilson, Erica L; Kim, Younggy

2016-05-01

In conventional wastewater treatment, waste sludge management and disposal contribute the major cost for wastewater treatment. Bioelectrochemical systems, as a potential alternative for future wastewater treatment and resources recovery, are expected to produce small amounts of waste sludge because exoelectrogenic bacteria grow on anaerobic respiration and form highly populated biofilms on bioanode surfaces. While waste sludge production is governed by the yield and decay coefficient, none of previous studies have quantified these kinetic constants for exoelectrogenic bacteria. For yield coefficient estimation, we modified McCarty's free energy-based model by using the bioanode potential for the free energy of the electron acceptor reaction. The estimated true yield coefficient ranged 0.1 to 0.3 g-VSS (volatile suspended solids) g-COD(-1) (chemical oxygen demand), which is similar to that of most anaerobic microorganisms. The yield coefficient was sensitively affected by the bioanode potential and pH while the substrate and bicarbonate concentrations had relatively minor effects on the yield coefficient. In lab-scale experiments using microbial electrolysis cells, the observed yield coefficient (including the effect of cell decay) was found to be 0.020 ± 0.008 g-VSS g-COD(-1), which is an order of magnitude smaller than the theoretical estimation. Based on the difference between the theoretical and experimental results, the decay coefficient was approximated to be 0.013 ± 0.002 d(-1). These findings indicate that bioelectrochemical systems have potential for future wastewater treatment with reduced waste sludge as well as for resources recovery. Also, the found kinetic information will allow accurate estimation of wastewater treatment performance in bioelectrochemical systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Development of a silicon limitation inducible expression system for recombinant protein production in the centric diatoms Thalassiosira pseudonana and Cyclotella cryptica

DOE PAGES

Shrestha, Roshan P.; Hildebrand, Mark

2017-08-17

An inducible promoter for recombinant protein expression provides substantial benefits because under induction conditions cellular energy and metabolic capability can be directed into protein synthesis. The most widely used inducible promoter for diatoms is for nitrate reductase, however, nitrogen metabolism is tied into diverse aspects of cellular function, and the induction response is not necessarily robust. Silicon limitation offers a means to eliminate energy and metabolic flux into cell division processes, with little other detrimental effect on cellular function, and a protein expression system that works under those conditions could be advantageous. In this study, we evaluate a number ofmore » promoters for recombinant protein expression induced by silicon limitation and repressed by the presence of silicon in the diatoms Thalassiosira pseudonana and Cyclotella cryptica. In addition to silicon limitation, we describe additional strategies to elevate recombinant protein expression level, including inclusion of the 5' fragment of the coding region of the native gene and reducing carbon flow into ancillary processes of pigment synthesis and formation of photosynthetic storage products. We achieved yields of eGFP to 1.8% of total soluble protein in C. cryptica, which is about 3.6-fold higher than that obtained with chloroplast expression and ninefold higher than nuclear expression in another well-established algal system. Our studies demonstrate that the combination of inducible promoter and other strategies can result in robust expression of recombinant protein in a nuclear-based expression system in diatoms under silicon limited conditions, separating the protein expression regime from growth processes and improving overall recombinant protein yields.« less
Development of a silicon limitation inducible expression system for recombinant protein production in the centric diatoms Thalassiosira pseudonana and Cyclotella cryptica

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

Shrestha, Roshan P.; Hildebrand, Mark

An inducible promoter for recombinant protein expression provides substantial benefits because under induction conditions cellular energy and metabolic capability can be directed into protein synthesis. The most widely used inducible promoter for diatoms is for nitrate reductase, however, nitrogen metabolism is tied into diverse aspects of cellular function, and the induction response is not necessarily robust. Silicon limitation offers a means to eliminate energy and metabolic flux into cell division processes, with little other detrimental effect on cellular function, and a protein expression system that works under those conditions could be advantageous. In this study, we evaluate a number ofmore » promoters for recombinant protein expression induced by silicon limitation and repressed by the presence of silicon in the diatoms Thalassiosira pseudonana and Cyclotella cryptica. In addition to silicon limitation, we describe additional strategies to elevate recombinant protein expression level, including inclusion of the 5' fragment of the coding region of the native gene and reducing carbon flow into ancillary processes of pigment synthesis and formation of photosynthetic storage products. We achieved yields of eGFP to 1.8% of total soluble protein in C. cryptica, which is about 3.6-fold higher than that obtained with chloroplast expression and ninefold higher than nuclear expression in another well-established algal system. Our studies demonstrate that the combination of inducible promoter and other strategies can result in robust expression of recombinant protein in a nuclear-based expression system in diatoms under silicon limited conditions, separating the protein expression regime from growth processes and improving overall recombinant protein yields.« less
Online evaluation of a commercial video image analysis system (Computer Vision System) to predict beef carcass red meat yield and for augmenting the assignment of USDA yield grades. United States Department of Agriculture.

PubMed

Cannell, R C; Belk, K E; Tatum, J D; Wise, J W; Chapman, P L; Scanga, J A; Smith, G C

2002-05-01

Objective quantification of differences in wholesale cut yields of beef carcasses at plant chain speeds is important for the application of value-based marketing. This study was conducted to evaluate the ability of a commercial video image analysis system, the Computer Vision System (CVS) to 1) predict commercially fabricated beef subprimal yield and 2) augment USDA yield grading, in order to improve accuracy of grade assessment. The CVS was evaluated as a fully installed production system, operating on a full-time basis at chain speeds. Steer and heifer carcasses (n = 296) were evaluated using CVS, as well as by USDA expert and online graders, before the fabrication of carcasses into industry-standard subprimal cuts. Expert yield grade (YG), online YG, CVS estimated carcass yield, and CVS measured ribeye area in conjunction with expert grader estimates of the remaining YG factors (adjusted fat thickness, percentage of kidney-pelvic-heart fat, hot carcass weight) accounted for 67, 39, 64, and 65% of the observed variation in fabricated yields of closely trimmed subprimals. The dual component CVS predicted wholesale cut yields more accurately than current online yield grading, and, in an augmentation system, CVS ribeye measurement replaced estimated ribeye area in determination of USDA yield grade, and the accuracy of cutability prediction was improved, under packing plant conditions and speeds, to a level close to that of expert graders applying grades at a comfortable rate of speed offline.
Baculovirus expression system and method for high throughput expression of genetic material

DOEpatents

Clark, Robin; Davies, Anthony

2001-01-01

The present invention provides novel recombinant baculovirus expression systems for expressing foreign genetic material in a host cell. Such expression systems are readily adapted to an automated method for expression foreign genetic material in a high throughput manner. In other aspects, the present invention features a novel automated method for determining the function of foreign genetic material by transfecting the same into a host by way of the recombinant baculovirus expression systems according to the present invention.
Seed-Specific Expression of OsDWF4, a Rate-Limiting Gene Involved in Brassinosteroids Biosynthesis, Improves Both Grain Yield and Quality in Rice.

PubMed

Li, Qian-Feng; Yu, Jia-Wen; Lu, Jun; Fei, Hong-Yuan; Luo, Ming; Cao, Bu-Wei; Huang, Li-Chun; Zhang, Chang-Quan; Liu, Qiao-Quan

2018-04-18

Brassinosteroids (BRs) are essential plant-specific steroidal hormones that regulate diverse growth and developmental processes in plants. We evaluated the effects of OsDWF4, a gene that encodes a rate-limiting enzyme in BR biosynthesis, on both rice yield and quality when driven by the Gt1 or Ubi promoter, which correspond to seed-specific or constitutive expression, respectively. Generally, transgenic plants expressing OsDWF4 showed increased grain yield with more tillers and longer and heavier seeds. Moreover, the starch physicochemical properties of the transgenic rice were also improved. Interestingly, OsDWF4 was found to exert different effects on either rice yield or quality when driven by the different promoters. The overall performance of the pGt1::OsDWF4 lines was better than that of the pUbi::OsDWF4 lines. Our data not only demonstrate the effects of OsDWF4 overexpression on both rice yield and quality but also suggest that a seed-specific promoter is a good choice in BR-mediated rice breeding programs.
Field-scale experiments reveal persistent yield gaps in low-input and organic cropping systems

PubMed Central

Kravchenko, Alexandra N.; Snapp, Sieglinde S.; Robertson, G. Philip

2017-01-01

Knowledge of production-system performance is largely based on observations at the experimental plot scale. Although yield gaps between plot-scale and field-scale research are widely acknowledged, their extent and persistence have not been experimentally examined in a systematic manner. At a site in southwest Michigan, we conducted a 6-y experiment to test the accuracy with which plot-scale crop-yield results can inform field-scale conclusions. We compared conventional versus alternative, that is, reduced-input and biologically based–organic, management practices for a corn–soybean–wheat rotation in a randomized complete block-design experiment, using 27 commercial-size agricultural fields. Nearby plot-scale experiments (0.02-ha to 1.0-ha plots) provided a comparison of plot versus field performance. We found that plot-scale yields well matched field-scale yields for conventional management but not for alternative systems. For all three crops, at the plot scale, reduced-input and conventional managements produced similar yields; at the field scale, reduced-input yields were lower than conventional. For soybeans at the plot scale, biological and conventional managements produced similar yields; at the field scale, biological yielded less than conventional. For corn, biological management produced lower yields than conventional in both plot- and field-scale experiments. Wheat yields appeared to be less affected by the experimental scale than corn and soybean. Conventional management was more resilient to field-scale challenges than alternative practices, which were more dependent on timely management interventions; in particular, mechanical weed control. Results underscore the need for much wider adoption of field-scale experimentation when assessing new technologies and production-system performance, especially as related to closing yield gaps in organic farming and in low-resourced systems typical of much of the developing world. PMID:28096409
Field-scale experiments reveal persistent yield gaps in low-input and organic cropping systems.

PubMed

Kravchenko, Alexandra N; Snapp, Sieglinde S; Robertson, G Philip

2017-01-31

Knowledge of production-system performance is largely based on observations at the experimental plot scale. Although yield gaps between plot-scale and field-scale research are widely acknowledged, their extent and persistence have not been experimentally examined in a systematic manner. At a site in southwest Michigan, we conducted a 6-y experiment to test the accuracy with which plot-scale crop-yield results can inform field-scale conclusions. We compared conventional versus alternative, that is, reduced-input and biologically based-organic, management practices for a corn-soybean-wheat rotation in a randomized complete block-design experiment, using 27 commercial-size agricultural fields. Nearby plot-scale experiments (0.02-ha to 1.0-ha plots) provided a comparison of plot versus field performance. We found that plot-scale yields well matched field-scale yields for conventional management but not for alternative systems. For all three crops, at the plot scale, reduced-input and conventional managements produced similar yields; at the field scale, reduced-input yields were lower than conventional. For soybeans at the plot scale, biological and conventional managements produced similar yields; at the field scale, biological yielded less than conventional. For corn, biological management produced lower yields than conventional in both plot- and field-scale experiments. Wheat yields appeared to be less affected by the experimental scale than corn and soybean. Conventional management was more resilient to field-scale challenges than alternative practices, which were more dependent on timely management interventions; in particular, mechanical weed control. Results underscore the need for much wider adoption of field-scale experimentation when assessing new technologies and production-system performance, especially as related to closing yield gaps in organic farming and in low-resourced systems typical of much of the developing world.
Heterologous expression of a recombinant lactobacillal β-galactosidase in Lactobacillus plantarum: effect of different parameters on the sakacin P-based expression system.

PubMed

Nguyen, Tien-Thanh; Nguyen, Hoang-Minh; Geiger, Barbara; Mathiesen, Geir; Eijsink, Vincent G H; Peterbauer, Clemens K; Haltrich, Dietmar; Nguyen, Thu-Ha

2015-03-07

Two overlapping genes lacL and lacM (lacLM) encoding for heterodimeric β-galactosidase from Lactobacillus reuteri were previously cloned and over-expressed in the food-grade host strain Lactobacillus plantarum WCFS1, using the inducible lactobacillal pSIP expression system. In this study, we analyzed different factors that affect the production of recombinant L. reuteri β-galactosidase. Various factors related to the cultivation, i.e. culture pH, growth temperature, glucose concentration, as well as the induction conditions, including cell concentration at induction point and inducer concentration, were tested. Under optimal fermentation conditions, the maximum β-galactosidase levels obtained were 130 U/mg protein and 35-40 U/ml of fermentation broth corresponding to the formation of approximately 200 mg of recombinant protein per litre of fermentation medium. As calculated from the specific activity of the purified enzyme (190 U/mg), β-galactosidase yield amounted to roughly 70% of the total soluble intracellular protein of the host organism. It was observed that pH and substrate (glucose) concentration are the most prominent factors affecting the production of recombinant β-galactosidase. The over-expression of recombinant L. reuteri β-galactosidase in a food-grade host strain was optimized, which is of interest for applications of this enzyme in the food industry. The results provide more detailed insight into these lactobacillal expression systems and confirm the potential of the pSIP system for efficient, tightly controlled expression of enzymes and proteins in lactobacilli.
Critical design criteria for minimal antibiotic-free plasmid vectors necessary to combine robust RNA Pol II and Pol III-mediated eukaryotic expression with high bacterial production yields

PubMed Central

Carnes, Aaron E.; Luke, Jeremy M.; Vincent, Justin M.; Anderson, Sheryl; Schukar, Angela; Hodgson, Clague P.; Williams, James A.

2010-01-01

Background For safety considerations, regulatory agencies recommend elimination of antibiotic resistance markers and nonessential sequences from plasmid DNA-based gene medicines. In the present study we analyzed antibiotic-free (AF) vector design criteria impacting bacterial production and mammalian transgene expression. Methods Both CMV-HTLV-I R RNA Pol II promoter (protein transgene) and murine U6 RNA Pol III promoter (RNA transgene) vector designs were studied. Plasmid production yield was assessed through inducible fed-batch fermentation. RNA Pol II-directed EGFP and RNA Pol III-directed RNA expression were quantified by fluorometry and quantitative real-time polymerase chain reaction (RT-PCR), respectively, after transfection of human HEK293 cells. Results Sucrose-selectable minimalized protein and therapeutic RNA expression vector designs that combined an RNA-based AF selection with highly productive fermentation manufacturing (>1,000 mg/L plasmid DNA) and high level in vivo expression of encoded products were identified. The AF selectable marker was also successfully applied to convert existing kanamycin-resistant DNA vaccine plasmids gWIZ and pVAX1 into AF vectors, demonstrating a general utility for retrofitting existing vectors. A minimum vector size for high yield plasmid fermentation was identified. A strategy for stable fermentation of plasmid dimers with improved vector potency and fermentation yields up to 1,740 mg/L was developed. Conclusions We report the development of potent high yield AF gene medicine expression vectors for protein or RNA (e.g. short hairpin RNA or microRNA) products. These AF expression vectors were optimized to exceed a newly identified size threshold for high copy plasmid replication and direct higher transgene expression levels than alternative vectors. PMID:20806425
Control of root system architecture by DEEPER ROOTING 1 increases rice yield under drought conditions.

PubMed

Uga, Yusaku; Sugimoto, Kazuhiko; Ogawa, Satoshi; Rane, Jagadish; Ishitani, Manabu; Hara, Naho; Kitomi, Yuka; Inukai, Yoshiaki; Ono, Kazuko; Kanno, Noriko; Inoue, Haruhiko; Takehisa, Hinako; Motoyama, Ritsuko; Nagamura, Yoshiaki; Wu, Jianzhong; Matsumoto, Takashi; Takai, Toshiyuki; Okuno, Kazutoshi; Yano, Masahiro

2013-09-01

The genetic improvement of drought resistance is essential for stable and adequate crop production in drought-prone areas. Here we demonstrate that alteration of root system architecture improves drought avoidance through the cloning and characterization of DEEPER ROOTING 1 (DRO1), a rice quantitative trait locus controlling root growth angle. DRO1 is negatively regulated by auxin and is involved in cell elongation in the root tip that causes asymmetric root growth and downward bending of the root in response to gravity. Higher expression of DRO1 increases the root growth angle, whereby roots grow in a more downward direction. Introducing DRO1 into a shallow-rooting rice cultivar by backcrossing enabled the resulting line to avoid drought by increasing deep rooting, which maintained high yield performance under drought conditions relative to the recipient cultivar. Our experiments suggest that control of root system architecture will contribute to drought avoidance in crops.
Asetek's Warm-Water Liquid Cooling System Yields Energy Cost Savings at

Science.gov Websites

NREL | Energy Systems Integration Facility | NREL Asetek Asetek's Warm-Water Liquid Cooling System Yields Energy Cost Savings at NREL Asetek's RackCDU liquid cooling system was installed and tested at the Energy Systems Integration Facility's (ESIF's) ultra-energy-efficient high-performance
A novel riboregulator switch system of gene expression for enhanced microbial production of succinic acid.

PubMed

Wang, Jing; Wang, Haoyuan; Yang, Le; Lv, Liping; Zhang, Zhe; Ren, Bin; Dong, Lichun; Li, Ning

2018-04-01

In this paper, a novel riboregulator Switch System of Gene Expression including an OFF-TO-ON switch and an ON-TO-OFF switch was designed to regulate the expression state of target genes between "ON" and "OFF" by switching the identifiability of ribosome recognition site (RBS) based on the thermodynamic stability of different RNA-RNA hybridizations between RBS and small noncoding RNAs. The proposed riboregulator switch system was employed for the fermentative production of succinic acid using an engineered strain of E. coli JW1021, during which the expression of mgtC gene was controlled at "ON" state and that of pepc and ecaA genes were controlled at the "OFF" state in the lag phase and switched to the "OFF" and "ON" state once the strain enters the logarithmic phase. The results showed that using the strain of JW1021, the yield and productivity of succinic acid can reach 0.91 g g -1 and 3.25 g L -1 h -1 , respectively, much higher than those using the strains without harboring the riboregulator switch system.
Optimizing rice yields while minimizing yield-scaled global warming potential.

PubMed

Pittelkow, Cameron M; Adviento-Borbe, Maria A; van Kessel, Chris; Hill, James E; Linquist, Bruce A

2014-05-01

To meet growing global food demand with limited land and reduced environmental impact, agricultural greenhouse gas (GHG) emissions are increasingly evaluated with respect to crop productivity, i.e., on a yield-scaled as opposed to area basis. Here, we compiled available field data on CH4 and N2 O emissions from rice production systems to test the hypothesis that in response to fertilizer nitrogen (N) addition, yield-scaled global warming potential (GWP) will be minimized at N rates that maximize yields. Within each study, yield N surplus was calculated to estimate deficit or excess N application rates with respect to the optimal N rate (defined as the N rate at which maximum yield was achieved). Relationships between yield N surplus and GHG emissions were assessed using linear and nonlinear mixed-effects models. Results indicate that yields increased in response to increasing N surplus when moving from deficit to optimal N rates. At N rates contributing to a yield N surplus, N2 O and yield-scaled N2 O emissions increased exponentially. In contrast, CH4 emissions were not impacted by N inputs. Accordingly, yield-scaled CH4 emissions decreased with N addition. Overall, yield-scaled GWP was minimized at optimal N rates, decreasing by 21% compared to treatments without N addition. These results are unique compared to aerobic cropping systems in which N2 O emissions are the primary contributor to GWP, meaning yield-scaled GWP may not necessarily decrease for aerobic crops when yields are optimized by N fertilizer addition. Balancing gains in agricultural productivity with climate change concerns, this work supports the concept that high rice yields can be achieved with minimal yield-scaled GWP through optimal N application rates. Moreover, additional improvements in N use efficiency may further reduce yield-scaled GWP, thereby strengthening the economic and environmental sustainability of rice systems. © 2013 John Wiley & Sons Ltd.
Ecological intensification of cereal production systems: yield potential, soil quality, and precision agriculture.

PubMed

Cassman, K G

1999-05-25

Wheat (Triticum aestivum L.), rice (Oryza sativa L.), and maize (Zea mays L.) provide about two-thirds of all energy in human diets, and four major cropping systems in which these cereals are grown represent the foundation of human food supply. Yield per unit time and land has increased markedly during the past 30 years in these systems, a result of intensified crop management involving improved germplasm, greater inputs of fertilizer, production of two or more crops per year on the same piece of land, and irrigation. Meeting future food demand while minimizing expansion of cultivated area primarily will depend on continued intensification of these same four systems. The manner in which further intensification is achieved, however, will differ markedly from the past because the exploitable gap between average farm yields and genetic yield potential is closing. At present, the rate of increase in yield potential is much less than the expected increase in demand. Hence, average farm yields must reach 70-80% of the yield potential ceiling within 30 years in each of these major cereal systems. Achieving consistent production at these high levels without causing environmental damage requires improvements in soil quality and precise management of all production factors in time and space. The scope of the scientific challenge related to these objectives is discussed. It is concluded that major scientific breakthroughs must occur in basic plant physiology, ecophysiology, agroecology, and soil science to achieve the ecological intensification that is needed to meet the expected increase in food demand.
Enhanced artemisinin yield by expression of rol genes in Artemisia annua.

PubMed

Dilshad, Erum; Cusido, Rosa Maria; Palazon, Javier; Estrada, Karla Ramirez; Bonfill, Mercedes; Mirza, Bushra

2015-10-29

Despite of many advances in the treatment of malaria, it is still the fifth most prevalent disease worldwide and is one of the major causes of death in the developing countries which accounted for 584,000 deaths in 2013, as estimated by World Health Organization. Artemisinin from Artemisia annua is still one of the most effective treatments for malaria. Increasing the artemisinin content of A. annua plants by genetic engineering would improve the availability of this much-needed drug. In this regard, a high artemisinin-yielding hybrid of A. annua produced by the centre for novel agricultural products of the University of York, UK, was selected (artemisinin maximally 1.4 %). As rol genes are potential candidates of biochemical engineering, genetic transformation of A. annua with Agrobacterium tumefaciens GV3101 harbouring vectors with rol B and rol C genes was carried out with the objective of enhancement of artemisinin content. Transgenic lines produced were analysed by the LC-MS for quantitative analysis of artemisinin and analogues. These high artemisinin yielding transgenics were also analysed by real time quantitative PCR to find the molecular dynamics of artemisinin enhancement. Genes of artemisinin biosynthetic pathway were studied including amorphadiene synthase (ADS), cytochrome P450, (CYP71AV1) and aldehyde dehydrogenase 1 (ALDH1). Trichome-specific fatty acyl-CoA reductase 1(TAFR1) is an enzyme involved in both trichome development and sesquiterpenoid biosynthesis and both processes are important for artemisinin biosynthesis. Thus, real time qPCR analysis of the TAFR1 gene was carried out, and trichome density was determined. Transgenics of rol B gene showed two- to ninefold (the decimal adds nothing in the abstract, please simplify to two- to ninefold) increase in artemisinin, 4-12-fold increase in artesunate and 1.2-3-fold increase in dihydroartemisinin. Whereas in the case of rol C gene transformants, a fourfold increase in artemisinin, four to
Different universality classes at the yielding transition of amorphous systems

NASA Astrophysics Data System (ADS)

Jagla, E. A.

2017-08-01

We study the yielding transition of a two-dimensional amorphous system under shear by using a mesoscopic elasto-plastic model. The model combines a full (tensorial) description of the elastic interactions in the system and the possibility of structural reaccommodations that are responsible for the plastic behavior. The possible structural reaccommodations are encoded in the form of a "plastic disorder" potential, which is chosen independently at each position of the sample to account for local heterogeneities. We observe that the stress must exceed a critical value σc in order for the system to yield. In addition, when the system yields a flow curve (relating stress σ and strain rate γ ˙) of the form γ ˙˜(σ-σc) β is obtained. Remarkably, we observe the value of β to depend on some details of the plastic disorder potential. For smooth potentials a value of β ≃2.0 is obtained, whereas for potentials obtained as a concatenation of smooth pieces a value β ≃1.5 is observed in the simulations. This indicates a dependence of critical behavior on details of the plastic behavior. In addition, by integrating out nonessential, harmonic degrees of freedom, we derive a simplified scalar version of the model that represents a collection of interacting Prandtl-Tomlinson particles. A mean-field treatment of this interaction reproduces the difference of β exponents for the two classes of plastic disorder potentials and provides values of β that compare favorably with those found in the full simulations.
High-level expression of recombinant beta-galactosidases in Lactobacillus plantarum and Lactobacillus sakei using a Sakacin P-based expression system.

PubMed

Halbmayr, Elisabeth; Mathiesen, Geir; Nguyen, Thu-Ha; Maischberger, Thomas; Peterbauer, Clemens K; Eijsink, Vincent G H; Haltrich, Dietmar

2008-06-25

This work presents the cloning and expression of the genes encoding heterodimeric beta-galactosidases from Lactobacillus reuteri L103, Lactobacillus acidophilus R22, Lactobacillus plantarum WCFS1, and Lactobacillus sakei Lb790. These enzymes consist of two subunits of approximately 73 and 35 kDa, which are encoded by two overlapping genes, lacL and lacM, respectively. We have cloned these genes into the lactobacillal expression vectors pSIP403 and pSIP409, which are based on the sakacin P operon of L. sakei ( Sørvig et al. Microbiology 2005, 151, 2439- 2449 ), and expressed them in the host strains L. plantarum WCFS1 and L. sakei Lb790. Results varied considerably, ranging from 2.23 to 61.1 U/mg of beta-galactosidase activity, depending on the origin of the lacLM genes, the host strain, and the expression vector used. Highest expression levels were obtained in a laboratory cultivation of L. plantarum WCFS1 harboring the plasmid pEH3R containing the lacLM gene from L. reuteri L103. These cultivations yielded approximately 23 000 U of beta-galactosidase activity per liter, corresponding to the formation of roughly 100 mg of recombinant protein per liter of fermentation medium, and beta-galactosidase levels amounted to 55% of the total intracellular protein of the host organism. To further verify the suitability of this expression system, recombinant beta-galactosidase from L. reuteri was purified to apparent homogeneity. The properties of the purified enzyme were essentially identical with the properties of purified native beta-galactosidase from L. reuteri L103. The presented results lead the way to efficient overproduction of beta-galactosidase in a food-grade expression system, which is of high interest for applications in food industry.
Secretory expression of Lentinula edodes intracellular laccase by yeast high-cell-density system: sub-milligram production of difficult-to-express secretory protein.

PubMed

Kurose, Takeshi; Saito, Yuta; Kimata, Koichi; Nakagawa, Yuko; Yano, Akira; Ito, Keisuke; Kawarasaki, Yasuaki

2014-06-01

While a number of heterologous expression systems have been reported for extracellular laccases, there are few for the intracellular counterparts. The Lentinula edodes intracellular laccase Lcc4 is an industrially potential enzyme with its unique substrate specificity. The heterologous production of the intracellular laccase, however, had been difficult because of its expression-dependent toxicity. We previously demonstrated that recombinant yeast cells synthesized and, interestingly, secreted Lcc4 only when they were suspended to an inducing medium in a high cell-density (J. Biosci. Bioeng., 113, 154-159, 2012). The high cell-density system was versatile and applicable to other difficult-to-express secretory proteins. Nevertheless, the system's great dependence on aeration, which was a practical obstacle to scale-up production of the enzyme and some other proteins, left the secretion pathway and enzymatic properties of the Lcc4 uncharacterized. In this report, we demonstrate a successful production of Lcc4 by applying a jar-fermentor to the high cell-density system. The elevated yield (0.6 mg L(-1)) due to the sufficient aeration allowed us to prepare and purify the enzyme to homogeneity. The enzyme had been secreted as a hyper-glycosylated protein, resulting in smear band-formations in SDS-PAGE. The amino acid sequencing analysis suggested that the N-terminal 17 residues had been recognized as a secretion signal. The recombinant enzyme showed similar enzymatic properties to the naturally occurring Lcc4. The characteristics of the scale-upped expression system, which includes helpful information for the potential users, have also been described. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
A novel regulation mechanism of the T7 RNA polymerase based expression system improves overproduction and folding of membrane proteins.

PubMed

Angius, Federica; Ilioaia, Oana; Amrani, Amira; Suisse, Annabelle; Rosset, Lindsay; Legrand, Amélie; Abou-Hamdan, Abbas; Uzan, Marc; Zito, Francesca; Miroux, Bruno

2018-06-05

Membrane protein (MP) overproduction is one of the major bottlenecks in structural genomics and biotechnology. Despite the emergence of eukaryotic expression systems, bacteria remain a cost effective and powerful tool for protein production. The T7 RNA polymerase (T7RNAP)-based expression system is a successful and efficient expression system, which achieves high-level production of proteins. However some foreign MPs require a fine-tuning of their expression to minimize the toxicity associated with their production. Here we report a novel regulation mechanism for the T7 expression system. We have isolated two bacterial hosts, namely C44(DE3) and C45(DE3), harboring a stop codon in the T7RNAP gene, whose translation is under the control of the basal nonsense suppressive activity of the BL21(DE3) host. Evaluation of hosts with superfolder green fluorescent protein (sfGFP) revealed an unprecedented tighter control of transgene expression with a marked accumulation of the recombinant protein during stationary phase. Analysis of a collection of twenty MP fused to GFP showed an improved production yield and quality of several bacterial MPs and of one human monotopic MP. These mutant hosts are complementary to the other existing T7 hosts and will increase the versatility of the T7 expression system.
Genome shuffling of Saccharomyces cerevisiae for enhanced glutathione yield and relative gene expression analysis using fluorescent quantitation reverse transcription polymerase chain reaction.

PubMed

Yin, Hua; Ma, Yanlin; Deng, Yang; Xu, Zhenbo; Liu, Junyan; Zhao, Junfeng; Dong, Jianjun; Yu, Junhong; Chang, Zongming

2016-08-01

Genome shuffling is an efficient and promising approach for the rapid improvement of microbial phenotypes. In this study, genome shuffling was applied to enhance the yield of glutathione produced by Saccharomyces cerevisiae YS86. Six isolates with subtle improvements in glutathione yield were obtained from populations generated by ultraviolet (UV) irradiation and nitrosoguanidine (NTG) mutagenesis. These yeast strains were then subjected to recursive pool-wise protoplast fusion. A strain library that was likely to yield positive colonies was created by fusing the lethal protoplasts obtained from both UV irradiation and heat treatments. After two rounds of genome shuffling, a high-yield recombinant YSF2-19 strain that exhibited 3.2- and 3.3-fold increases in glutathione production in shake flask and fermenter respectively was obtained. Comparative analysis of synthetase gene expression was conducted between the initial and shuffled strains using FQ (fluorescent quantitation) RT-PCR (reverse transcription polymerase chain reaction). Delta CT (threshold cycle) relative quantitation analysis revealed that glutathione synthetase gene (GSH-I) expression at the transcriptional level in the YSF2-19 strain was 9.9-fold greater than in the initial YS86. The shuffled yeast strain has a potential application in brewing, other food, and pharmaceutical industries. Simultaneously, the analysis of improved phenotypes will provide more valuable data for inverse metabolic engineering. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluation of the Pichia pastoris expression system for the production of GPCRs for structural analysis

PubMed Central

2011-01-01

Background Various protein expression systems, such as Escherichia coli (E. coli), Saccharomyces cerevisiae (S. cerevisiae), Pichia pastoris (P. pastoris), insect cells and mammalian cell lines, have been developed for the synthesis of G protein-coupled receptors (GPCRs) for structural studies. Recently, the crystal structures of four recombinant human GPCRs, namely β2 adrenergic receptor, adenosine A2a receptor, CXCR4 and dopamine D3 receptor, were successfully determined using an insect cell expression system. GPCRs expressed in insect cells are believed to undergo mammalian-like posttranscriptional modifications and have similar functional properties than in mammals. Crystal structures of GPCRs have not yet been solved using yeast expression systems. In the present study, P. pastoris and insect cell expression systems for the human muscarinic acetylcholine receptor M2 subtype (CHRM2) were developed and the quantity and quality of CHRM2 synthesized by both expression systems were compared for the application in structural studies. Results The ideal conditions for the expression of CHRM2 in P. pastoris were 60 hr at 20°C in a buffer of pH 7.0. The specific activity of the expressed CHRM2 was 28.9 pmol/mg of membrane protein as determined by binding assays using [3H]-quinuclidinyl benzilate (QNB). Although the specific activity of the protein produced by P. pastoris was lower than that of Sf9 insect cells, CHRM2 yield in P. pastoris was 2-fold higher than in Sf9 insect cells because P. pastoris was cultured at high cell density. The dissociation constant (Kd) for QNB in P. pastoris was 101.14 ± 15.07 pM, which was similar to that in Sf9 insect cells (86.23 ± 8.57 pM). There were no differences in the binding affinity of CHRM2 for QNB between P. pastoris and Sf9 insect cells. Conclusion Compared to insect cells, P. pastoris is easier to handle, can be grown at lower cost, and can be expressed quicker at a large scale. Yeast, P. pastoris, and insect cells are all
Applicability and methodology of determining sustainable yield in groundwater systems

NASA Astrophysics Data System (ADS)

Kalf, Frans R. P.; Woolley, Donald R.

2005-03-01

There is currently a need for a review of the definition and methodology of determining sustainable yield. The reasons are: (1) current definitions and concepts are ambiguous and non-physically based so cannot be used for quantitative application, (2) there is a need to eliminate varying interpretations and misinterpretations and provide a sound basis for application, (3) the notion that all groundwater systems either are or can be made to be sustainable is invalid, (4) often there are an excessive number of factors bound up in the definition that are not easily quantifiable, (5) there is often confusion between production facility optimal yield and basin sustainable yield, (6) in many semi-arid and arid environments groundwater systems cannot be sensibly developed using a sustained yield policy particularly where ecological constraints are applied. Derivation of sustainable yield using conservation of mass principles leads to expressions for basin sustainable, partial (non-sustainable) mining and total (non-sustainable) mining yields that can be readily determined using numerical modelling methods and selected on the basis of applied constraints. For some cases there has to be recognition that the groundwater resource is not renewable and its use cannot therefore be sustainable. In these cases, its destiny should be the best equitable use.
High-yield expression in Escherichia coli, purification and application of budding yeast K2 killer protein.

PubMed

Podoliankaitė, Monika; Lukša, Juliana; Vyšniauskis, Gintautas; Sereikaitė, Jolanta; Melvydas, Vytautas; Serva, Saulius; Servienė, Elena

2014-07-01

Saccharomyces cerevisiae K2 toxin is a highly active extracellular protein, important as a biocontrol agent for biotechnological applications in the wine industry. This protein is produced at negligible levels in yeast, making difficult to isolate it in amounts sufficient for investigation and generation of analysis tools. In this work, we demonstrate the use of a bacterial system for expression of the recombinant K2 protein, suitable for generation of antibodies specific for toxin of the yeast origin. Synthesis of the full-length S. cerevisiae K2 preprotoxin in Escherichia coli was found to be toxic to the host cell, resulting in diminished growth. Such effect was abolished by the introduction of the C-terminal truncation into K2 protein, directing it into non-toxic inclusion body fraction. The obtained protein is of limited solubility thus, facilitating the purification by simple and efficient chromatography-free procedure. The protein aggregates were successfully refolded into a soluble form yielding sufficient amounts of a tag-less truncated K2 protein suitable for polyclonal antibody production. Antibodies were raised in rabbit and found to be specific for detection of both antigen and native S. cerevisiae K2 toxin.
Heterologous Expression of ATG8c from Soybean Confers Tolerance to Nitrogen Deficiency and Increases Yield in Arabidopsis

PubMed Central

Liu, Dong; Chai, Wenting; Gong, Qingqiu; Wang, Ning Ning

2012-01-01

Nitrogen is an essential element for plant growth and yield. Improving Nitrogen Use Efficiency (NUE) of crops could potentially reduce the application of chemical fertilizer and alleviate environmental damage. To identify new NUE genes is therefore an important task in molecular breeding. Macroautophagy (autophagy) is an intracellular process in which damaged or obsolete cytoplasmic components are encapsulated in double membraned vesicles termed autophagosomes, then delivered to the vacuole for degradation and nutrient recycling. One of the core components of autophagosome formation, ATG8, has been shown to directly mediate autophagosome expansion, and the transcript of which is highly inducible upon starvation. Therefore, we postulated that certain homologs of Saccharomyces cerevisiae ATG8 (ScATG8) from crop species could have potential for NUE crop breeding. A soybean (Glycine max, cv. Zhonghuang-13) ATG8, GmATG8c, was selected from the 11 family members based on transcript analysis upon nitrogen deprivation. GmATG8c could partially complement the yeast atg8 mutant. Constitutive expression of GmATG8c in soybean callus cells not only enhanced nitrogen starvation tolerance of the cells but accelerated the growth of the calli. Transgenic Arabidopsis over-expressing GmATG8c performed better under extended nitrogen and carbon starvation conditions. Meanwhile, under optimum growth conditions, the transgenic plants grew faster, bolted earlier, produced larger primary and axillary inflorescences, eventually produced more seeds than the wild-type. In average, the yield was improved by 12.9%. We conclude that GmATG8c may serve as an excellent candidate for breeding crops with enhanced NUE and better yield. PMID:22629371
Constitutive expression of CaPLA1 conferred enhanced growth and grain yield in transgenic rice plants.

PubMed

Park, Ki Youl; Kim, Eun Yu; Seo, Young Sam; Kim, Woo Taek

2016-03-01

Phospholipids are not only important components of cell membranes, but participate in diverse processes in higher plants. In this study, we generated Capsicum annuum phospholipiase A1 (CaPLA1) overexpressing transgenic rice (Oryza sativa L.) plants under the control of the maize ubiquitin promoter. The T4 CaPLA1-overexpressing rice plants (Ubi:CaPLA1) had a higher root:shoot mass ratio than the wild-type plants in the vegetative stage. Leaf epidermal cells from transgenic plants had more cells than wild-type plants. Genes that code for cyclin and lipid metabolic enzymes were up-regulated in the transgenic lines. When grown under typical paddy field conditions, the transgenic plants produced more tillers, longer panicles and more branches per panicle than the wild-type plants, all of which resulted in greater grain yield. Microarray analysis suggests that gene expressions that are related with cell proliferation, lipid metabolism, and redox state were widely altered in CaPLA1-overexpressing transgenic rice plants. Ubi:CaPLA1 plants had a reduced membrane peroxidation state, as determined by malondialdehyde and conjugated diene levels and higher peroxidase activity than wild-type rice plants. Furthermore, three isoprenoid synthetic genes encoding terpenoid synthase, hydroxysteroid dehydrogenase and 3-hydroxy-3-methyl-glutaryl-CoA reductase were up-regulated in CaPLA1-overexpressing plants. We suggest that constitutive expression of CaPLA1 conferred increased grain yield with enhanced growth in transgenic rice plants by alteration of gene activities related with cell proliferation, lipid metabolism, membrane peroxidation state and isoprenoid biosynthesis.
RBSDesigner: software for designing synthetic ribosome binding sites that yields a desired level of protein expression.

PubMed

Na, Dokyun; Lee, Doheon

2010-10-15

RBSDesigner predicts the translation efficiency of existing mRNA sequences and designs synthetic ribosome binding sites (RBSs) for a given coding sequence (CDS) to yield a desired level of protein expression. The program implements the mathematical model for translation initiation described in Na et al. (Mathematical modeling of translation initiation for the estimation of its efficiency to computationally design mRNA sequences with a desired expression level in prokaryotes. BMC Syst. Biol., 4, 71). The program additionally incorporates the effect on translation efficiency of the spacer length between a Shine-Dalgarno (SD) sequence and an AUG codon, which is crucial for the incorporation of fMet-tRNA into the ribosome. RBSDesigner provides a graphical user interface (GUI) for the convenient design of synthetic RBSs. RBSDesigner is written in Python and Microsoft Visual Basic 6.0 and is publicly available as precompiled stand-alone software on the web (http://rbs.kaist.ac.kr). dhlee@kaist.ac.kr
Dual-component video image analysis system (VIASCAN) as a predictor of beef carcass red meat yield percentage and for augmenting application of USDA yield grades.

PubMed

Cannell, R C; Tatum, J D; Belk, K E; Wise, J W; Clayton, R P; Smith, G C

1999-11-01

An improved ability to quantify differences in the fabrication yields of beef carcasses would facilitate the application of value-based marketing. This study was conducted to evaluate the ability of the Dual-Component Australian VIASCAN to 1) predict fabricated beef subprimal yields as a percentage of carcass weight at each of three fat-trim levels and 2) augment USDA yield grading, thereby improving accuracy of grade placement. Steer and heifer carcasses (n = 240) were evaluated using VIASCAN, as well as by USDA expert and online graders, before fabrication of carcasses to each of three fat-trim levels. Expert yield grade (YG), online YG, VIASCAN estimates, and VIASCAN estimated ribeye area used to augment actual and expert grader estimates of the remaining YG factors (adjusted fat thickness, percentage of kidney-pelvic-heart fat, and hot carcass weight), respectively, 1) accounted for 51, 37, 46, and 55% of the variation in fabricated yields of commodity-trimmed subprimals, 2) accounted for 74, 54, 66, and 75% of the variation in fabricated yields of closely trimmed subprimals, and 3) accounted for 74, 54, 71, and 75% of the variation in fabricated yields of very closely trimmed subprimals. The VIASCAN system predicted fabrication yields more accurately than current online yield grading and, when certain VIASCAN-measured traits were combined with some USDA yield grade factors in an augmentation system, the accuracy of cutability prediction was improved, at packing plant line speeds, to a level matching that of expert graders applying grades at a comfortable rate.
Ectopic expression of Arabidopsis Target of Rapamycin (AtTOR) improves water-use efficiency and yield potential in rice

NASA Astrophysics Data System (ADS)

Bakshi, Achala; Moin, Mazahar; Kumar, M. Udaya; Reddy, Aramati Bindu Madhava; Ren, Maozhi; Datla, Raju; Siddiq, E. A.; Kirti, P. B.

2017-02-01

The target of Rapamycin (TOR) present in all eukaryotes is a multifunctional protein, regulating growth, development, protein translation, ribosome biogenesis, nutrient, and energy signaling. In the present study, ectopic expression of TOR gene of Arabidopsis thaliana in a widely cultivated indica rice resulted in enhanced plant growth under water-limiting conditions conferring agronomically important water-use efficiency (WUE) trait. The AtTOR high expression lines of rice exhibited profuse tillering, increased panicle length, increased plant height, high photosynthetic efficiency, chlorophyll content and low Δ13C. Δ13C, which is inversely related to high WUE, was as low as 17‰ in two AtTOR high expression lines. These lines were also insensitive to the ABA-mediated inhibition of seed germination. The significant upregulation of 15 stress-specific genes in high expression lines indicates their contribution to abiotic stress tolerance. The constitutive expression of AtTOR is also associated with significant transcriptional upregulation of putative TOR complex-1 components, OsRaptor and OsLST8. Glucose-mediated transcriptional activation of AtTOR gene enhanced lateral root formation. Taken together, our findings indicate that TOR, in addition to its multiple cellular functions, also plays an important role in response to abiotic stress and potentially enhances WUE and yield related attributes.
Material and methods to increase plant growth and yield

DOEpatents

Kirst, Matias

2015-09-15

The present invention relates to materials and methods for modulating growth rates, yield, and/or resistance to drought conditions in plants. In one embodiment, a method of the invention comprises increasing expression of an hc1 gene (or a homolog thereof that provides for substantially the same activity), or increasing expression or activity of the protein encoded by an hc1 gene thereof, in a plant, wherein expression of the hc1 gene or expression or activity of the protein encoded by an hc1 gene results in increased growth rate, yield, and/or drought resistance in the plant.
Materials and methods to increase plant growth and yield

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

Kirst, Matias

The present invention relates to materials and methods for modulating growth rates, yield, and/or resistance to drought conditions in plants. In one embodiment, a method of the invention comprises increasing expression of an hc1 gene (or a homolog thereof that provides for substantially the same activity), or increasing expression or activity of the protein encoded by an hc1 gene thereof, in a plant, wherein expression of the hc1 gene or expression or activity of the protein encoded by an hc1 gene results in increased growth rate, yield, and/or drought resistance in the plant.
The LIKE system, a novel protein expression toolbox for Bacillus subtilis based on the liaI promoter

PubMed Central

2012-01-01

Background Bacillus subtilis is a very important Gram-positive model organism of high biotechnological relevance, which is widely used as a host for the production of both secreted and cytoplasmic proteins. We developed a novel and efficient expression system, based on the liaI promoter (PliaI) from B. subtilis, which is under control of the LiaRS antibiotic-inducible two-component system. In the absence of a stimulus, this promoter is kept tightly inactive. Upon induction by cell wall antibiotics, it shows an over 100-fold increase in activity within 10 min. Results Based on these traits of PliaI, we developed a novel LiaRS-controlled gene expression system for B. subtilis (the “LIKE" system). Two expression vectors, the integrative pLIKE-int and the replicative pLIKE-rep, were constructed. To enhance the performance of the PliaI-derived system, site-directed mutagenesis was employed to optimize the ribosome binding site and alter its spacing to the initiation codon used for the translational fusion. The impact of these genetic modifications on protein production yield was measured using GFP as a model protein. Moreover, a number of tailored B. subtilis expression strains containing different markerless chromosomal deletions of the liaIH region were constructed to circumvent undesired protein production, enhance the positive autoregulation of the LiaRS system and thereby increase target gene expression strength from the PliaI promoter. Conclusions The LIKE protein expression system is a novel protein expression system, which offers a number of advantages over existing systems. Its major advantages are (i) a tightly switched-off promoter during exponential growth in the absence of a stimulus, (ii) a concentration-dependent activation of PliaI in the presence of suitable inducers, (iii) a very fast but transient response with a very high dynamic range of over 100-fold (up to 1,000-fold) induction, (iv) a choice from a range of well-defined, commercially available
System dynamics approach for modeling of sugar beet yield considering the effects of climatic variables.

PubMed

Pervin, Lia; Islam, Md Saiful

2015-02-01

The aim of this study was to develop a system dynamics model for computation of yields and to investigate the dependency of yields on some major climatic parameters, i.e. temperature and rainfall, for Beta vulgaris subsp. (sugar beet crops) under future climate change scenarios. A system dynamics model was developed which takes account of the effects of rainfall and temperature on sugar beet yields under limited irrigation conditions. A relationship was also developed between the seasonal evapotranspiration and seasonal growing degree days for sugar beet crops. The proposed model was set to run for the present time period of 1993-2012 and for the future period 2013-2040 for Lethbridge region (Alberta, Canada). The model provides sugar beet yields on a yearly basis which are comparable to the present field data. It was found that the future average yield will be increased at about 14% with respect to the present average yield. The proposed model can help to improve the understanding of soil water conditions and irrigation water requirements of an area under certain climatic conditions and can be used for future prediction of yields for any crops in any region (with the required information to be provided). The developed system dynamics model can be used as a supporting tool for decision making, for improvement of agricultural management practice of any region. © 2014 Society of Chemical Industry.
Yield response and economics of shallow subsurface drip irrigation systems

USDA-ARS?s Scientific Manuscript database

Field tests were conducted using shallow subsurface drip irrigation (S3DI) on cotton (Gossypium hirsutum, L.), corn (Zea mays, L.), and peanut (Arachis hypogeae, L.) in rotation to investigate yield potential and economic sustainability of this irrigation system technique over a six year period. Dri...
Transgenic Cotton Plants Expressing the HaHR3 Gene Conferred Enhanced Resistance to Helicoverpa armigera and Improved Cotton Yield

PubMed Central

Han, Qiang; Wang, Zhenzhen; He, Yunxin; Xiong, Yehui; Lv, Shun; Li, Shupeng; Zhang, Zhigang; Qiu, Dewen; Zeng, Hongmei

2017-01-01

RNA interference (RNAi) has been developed as an efficient technology. RNAi insect-resistant transgenic plants expressing double-stranded RNA (dsRNA) that is ingested into insects to silence target genes can affect the viability of these pests or even lead to their death. HaHR3, a molt-regulating transcription factor gene, was previously selected as a target expressed in bacteria and tobacco plants to control Helicoverpa armigera by RNAi technology. In this work, we selected the dsRNA-HaHR3 fragment to silence HaHR3 in cotton bollworm for plant mediated-RNAi research. A total of 19 transgenic cotton lines expressing HaHR3 were successfully cultivated, and seven generated lines were used to perform feeding bioassays. Transgenic cotton plants expressing dsHaHR3 were shown to induce high larval mortality and deformities of pupation and adult eclosion when used to feed the newly hatched larvae, and 3rd and 5th instar larvae of H. armigera. Moreover, HaHR3 transgenic cotton also demonstrated an improved cotton yield when compared with controls. PMID:28867769
Lumber Grade Yields for Graded Aspen Logs and Trees

Treesearch

Leland F. Hanks; Robert L. Brisbin

1978-01-01

Green lumber grade yields for aspen were determined for use with the U.S. Forest Service hardwood log and tree grades. The yields for logs are expressed in percent of total lumber tally volume, and those for trees are expressed in board feet. Overruns for the International 1/4-inch and Scribner log rules along with lumber recovery factors are shown by log grade.
Development of an optimized tetracycline-inducible expression system to increase the accumulation of interleukin-10 in tobacco BY-2 suspension cells.

PubMed

Bortesi, Luisa; Rademacher, Thomas; Schiermeyer, Andreas; Schuster, Flora; Pezzotti, Mario; Schillberg, Stefan

2012-07-11

Plant cell suspension cultures can be used for the production of valuable pharmaceutical and industrial proteins. When the recombinant protein is secreted into the culture medium, restricting expression to a defined growth phase can improve both the quality and quantity of the recovered product by minimizing proteolytic activity. Temporal restriction is also useful for recombinant proteins whose constitutive expression affects cell growth and viability, such as viral interleukin-10 (vIL-10). We have developed a novel, tetracycline-inducible system suitable for tobacco BY-2 suspension cells which increases the yields of vIL-10. The new system is based on a binary vector that is easier to handle than conventional vectors, contains an enhanced inducible promoter and 5'-UTR to improve yields, and incorporates a constitutively-expressed visible marker gene to allow the rapid and straightforward selection of the most promising transformed clones. Stable transformation of BY-2 cells with this vector, without extensive optimization of the induction conditions, led to a 3.5 fold increase in vIL-10 levels compared to constitutive expression in the same host. We have developed an effective and straightforward molecular farming platform technology that improves both the quality and the quantity of recombinant proteins produced in plant cells, particularly those whose constitutive expression has a negative impact on plant growth and development. Although we tested the platform using vIL-10 produced in BY-2 cells, it can be applied to other host/product combinations and is also useful for basic research requiring strictly controlled transgene expression.
Development of an optimized tetracycline-inducible expression system to increase the accumulation of interleukin-10 in tobacco BY-2 suspension cells

PubMed Central

2012-01-01

Background Plant cell suspension cultures can be used for the production of valuable pharmaceutical and industrial proteins. When the recombinant protein is secreted into the culture medium, restricting expression to a defined growth phase can improve both the quality and quantity of the recovered product by minimizing proteolytic activity. Temporal restriction is also useful for recombinant proteins whose constitutive expression affects cell growth and viability, such as viral interleukin-10 (vIL-10). Results We have developed a novel, tetracycline-inducible system suitable for tobacco BY-2 suspension cells which increases the yields of vIL-10. The new system is based on a binary vector that is easier to handle than conventional vectors, contains an enhanced inducible promoter and 5′-UTR to improve yields, and incorporates a constitutively-expressed visible marker gene to allow the rapid and straightforward selection of the most promising transformed clones. Stable transformation of BY-2 cells with this vector, without extensive optimization of the induction conditions, led to a 3.5 fold increase in vIL-10 levels compared to constitutive expression in the same host. Conclusions We have developed an effective and straightforward molecular farming platform technology that improves both the quality and the quantity of recombinant proteins produced in plant cells, particularly those whose constitutive expression has a negative impact on plant growth and development. Although we tested the platform using vIL-10 produced in BY-2 cells, it can be applied to other host/product combinations and is also useful for basic research requiring strictly controlled transgene expression. PMID:22784336
High-yield secretion of recombinant proteins expressed in tobacco cell culture with a designer glycopeptide tag: Process development.

PubMed

Zhang, Ningning; Gonzalez, Maria; Savary, Brett; Xu, Jianfeng

2016-03-01

Low-yield protein production remains the most significant economic hurdle with plant cell culture technology. Fusions of recombinant proteins with hydroxyproline-O-glycosylated designer glycopeptide tags have consistently boosted secreted protein yields. This prompted us to study the process development of this technology aiming to achieve productivity levels necessary for commercial viability. We used a tobacco BY-2 cell culture expressing EGFP as fusion with a glycopeptide tag comprised of 32 repeat of "Ser-Pro" dipeptide, or (SP)32 , to study cell growth and protein secretion, culture scale-up, and establishment of perfusion cultures for continuous production. The BY-2 cells accumulated low levels of cell biomass (~7.5 g DW/L) in Schenk & Hildebrandt medium, but secreted high yields of (SP)32 -tagged EGFP (125 mg/L). Protein productivity of the cell culture has been stable for 6.0 years. The BY-2 cells cultured in a 5-L bioreactor similarly produced high secreted protein yield at 131 mg/L. Successful operation of a cell perfusion culture for 30 days was achieved under the perfusion rate of 0.25 and 0.5 day(-1) , generating a protein volumetric productivity of 17.6 and 28.9 mg/day/L, respectively. This research demonstrates the great potential of the designer glycopeptide technology for use in commercial production of valuable proteins with plant cell cultures. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Freebies for Investors--Precise Incremental Yield Value

ERIC Educational Resources Information Center

Michelson, Irving

1977-01-01

Competition for savings dollars has led to free gift bonus offers as incentive for new deposits. A concise new formula presented here permits calculation of the total yield using an inexpensive minicomputer. Yield is expressed in terms of interest rate, effective discount value of gift bonus, and period of deposit. (Author/MA)
Expression systems for therapeutic glycoprotein production.

PubMed

Durocher, Yves; Butler, Michael

2009-12-01

There are slightly over 165 recombinant pharmaceuticals currently approved for human use. Another 500 protein candidates are in preclinical and clinical development, about 70% of these being glycosylated proteins. The need for expression systems allowing the efficient manufacturing of high quality glycoproteins is thus becoming imperative. Recent developments with CHO cells, the predominant mammalian expression system, have focused on either increasing cell specific productivity or prolonging the life span of cells in culture that translates to high integrated viable cell densities. These two factors have allowed volumetric productivities in excess of 5 g/L under conditions of controlled nutrient feeding. In addition to glycoengineering strategies, which are offering considerable advantage in producing proteins with enhanced therapeutic properties, several alternative expression systems are being developed for their manufacture, each with their advantages and limitations.

Using FACE systems to screen wheat cultivars for yield increases at elevated CO2

USDA-ARS?s Scientific Manuscript database

Because of continuing increases in atmospheric CO2, identifying cultivars of crops with larger yield increases at elevated CO2 may provide an avenue to increase crop yield potential in future climates. Free-air CO2 enrichment (FACE) systems have most often been used with multiple replications of ea...
Sex Roles and Yielded/Expressed Self-Control.

ERIC Educational Resources Information Center

Ganong, Lawrence H.; Coleman, Marilyn

1987-01-01

Results of a study of the impact of sex and sex role orientation on reported self-control behaviors showed that sex did not affect self-control or satisfaction with self-control, but sex role orientation did. Androgynous persons reported using more expressed self-control than others. (PS)
Effect of tillage system on yield and weed populations of soybean ( Glycin Max L.).

PubMed

Hosseini, Seyed Z; Firouzi, Saeed; Aminpanah, Hashem; Sadeghnejhad, Hamid R

2016-03-01

Field experiment was conducted at Agricultural and Natural Resources Research Center of Golestan Province, Iran, to determine the effects of tillage system and weed management regime on yield and weed populations in soybean ( Glycin max L.). The experimental design was a split plot where the whole plot portion was a randomized complete block with three replicates. Main plots were tillage system: 1- No-till row crop seeding, 2- No-till seed drilling, 3- Tillage with disc harrow and drill planting, 4- Tillage with chisel packer and drill planting. The subplots were weed management regimes: 1-Weed control with herbicide application, 2- Hand weeding, 3- Herbicide application plus hand weeding, and 4- Non-weeding. Results indicated that the main effects of tillage system and weed management regime were significant for seed yield, pod number per plant, seed number per pod, weed density and biomass, while their interaction were significant only for weed density, weed biomass, and seed number per pod. The highest grain yields (3838 kg ha-1) were recorded for No-till row crop seeding. The highest seed yield (3877 kg ha-1) also was recorded for weed control with herbicide and hand weeding treatment, followed by hand weeding (3379 kg ha-1).
Statistical modeling of yield and variance instability in conventional and organic cropping systems

USDA-ARS?s Scientific Manuscript database

Cropping systems research was undertaken to address declining crop diversity and verify competitiveness of alternatives to the predominant conventional cropping system in the northern Corn Belt. To understand and capitalize on temporal yield variability within corn and soybean fields, we quantified ...
Recombinant expression of extracellular domain of mutant Epidermal Growth Factor Receptor in prokaryotic and baculovirus expression systems.

PubMed

Vettath, Sunitha Kodengil; Shivashankar, Gaganashree; Menon, Krishnakumar N; Vijayachandran, Lakshmi S

2018-04-15

Epidermal Growth Factor Receptor variant III (EGFRvIII) is a tumor specific antigen detected in various tumors including gliomas, breast cancer, lung cancer, head and neck squamous cell carcinoma (HNSCC). Screening of EGFRvIII targeting drug molecules can be accelerated by developing drug screening platforms using recombinantly expressed protein. Choice of expression system is one of the major factors deciding the success of recombinant expression of a protein. In our study, we have tried to express and purify the extracellular domain (ECD) of this highly unstable protein using bacterial and baculovirus expression systems to select the expression system suited for our purpose. Even though the protein was successfully expressed in prokaryotic system, purification could be done only under denaturing conditions. But in the baculovirus expression system, the protein was expressed in soluble form and could be purified under native conditions, with single step of purification. Based on our results, we conclude that insect cells are better choice over E. coli cells for expressing EGFRvIII ECD in soluble form. This study provides insights for other researchers involved in expression of similar unstable membrane proteins, on selecting the best expression system and challenges involved. Copyright © 2018 Elsevier B.V. All rights reserved.
Surprising yields with no-till cropping systems

USDA-ARS?s Scientific Manuscript database

Producers using no-till practices have observed that crop yields can greatly exceed expectations based on nutrient and water supply. For example, Ralph Holzwarth, who farms near Gettysburg, SD, has averaged 150 bu/ac of corn on his farm for the past 6 years. We were surprised with this yield, as c...
Improved Production Efficiency of Virus-Like Particles by the Baculovirus Expression Vector System.

PubMed

López-Vidal, Javier; Gómez-Sebastián, Silvia; Bárcena, Juan; Nuñez, Maria del Carmen; Martínez-Alonso, Diego; Dudognon, Benoit; Guijarro, Eva; Escribano, José M

2015-01-01

Vaccines based on virus-like particles (VLPs) have proven effective in humans and animals. In this regard, the baculovirus expression vector system (BEVS) is one of the technologies of choice to generate such highly immunogenic vaccines. The extended use of these vaccines for human and animal populations is constrained because of high production costs, therefore a significant improvement in productivity is crucial to ensure their commercial viability. Here we describe the use of the previously described baculovirus expression cassette, called TB, to model the production of two VLP-forming vaccine antigens in insect cells. Capsid proteins from porcine circovirus type 2 (PCV2 Cap) and from the calicivirus that causes rabbit hemorrhagic disease (RHDV VP60) were expressed in insect cells using baculoviruses genetically engineered with the TB expression cassette. Productivity was compared to that obtained using standard counterpart vectors expressing the same proteins under the control of the polyhedrin promoter. Our results demonstrate that the use of the TB expression cassette increased the production yields of these vaccine antigens by around 300% with respect to the standard vectors. The recombinant proteins produced by TB-modified vectors were fully functional, forming VLPs identical in size and shape to those generated by the standard baculoviruses, as determined by electron microscopy analysis. The use of the TB expression cassette implies a simple modification of the baculovirus vectors that significantly improves the cost efficiency of VLP-based vaccine production, thereby facilitating the commercial viability and broad application of these vaccines for human and animal health.
Improved Production Efficiency of Virus-Like Particles by the Baculovirus Expression Vector System

PubMed Central

Bárcena, Juan; Nuñez, Maria del Carmen; Martínez-Alonso, Diego; Dudognon, Benoit; Guijarro, Eva; Escribano, José M.

2015-01-01

Vaccines based on virus-like particles (VLPs) have proven effective in humans and animals. In this regard, the baculovirus expression vector system (BEVS) is one of the technologies of choice to generate such highly immunogenic vaccines. The extended use of these vaccines for human and animal populations is constrained because of high production costs, therefore a significant improvement in productivity is crucial to ensure their commercial viability. Here we describe the use of the previously described baculovirus expression cassette, called TB, to model the production of two VLP-forming vaccine antigens in insect cells. Capsid proteins from porcine circovirus type 2 (PCV2 Cap) and from the calicivirus that causes rabbit hemorrhagic disease (RHDV VP60) were expressed in insect cells using baculoviruses genetically engineered with the TB expression cassette. Productivity was compared to that obtained using standard counterpart vectors expressing the same proteins under the control of the polyhedrin promoter. Our results demonstrate that the use of the TB expression cassette increased the production yields of these vaccine antigens by around 300% with respect to the standard vectors. The recombinant proteins produced by TB-modified vectors were fully functional, forming VLPs identical in size and shape to those generated by the standard baculoviruses, as determined by electron microscopy analysis. The use of the TB expression cassette implies a simple modification of the baculovirus vectors that significantly improves the cost efficiency of VLP-based vaccine production, thereby facilitating the commercial viability and broad application of these vaccines for human and animal health. PMID:26458221
Heterologous expression of VHb can improve the yield and quality of biocontrol fungus Paecilomyces lilacinus, during submerged fermentation.

PubMed

Zhang, Shumeng; Wang, Jieping; Wei, Yale; Tang, Qing; Ali, Maria Kanwal; He, Jin

2014-10-10

Paecilomyces lilacinus is an egg-parasitic fungus which is effective against plant-parasitic nematodes and it has been successfully commercialized for the control of many plant-parasitic nematodes. However, during the large-scale industrial fermentation process of the filamentous fungus, the dissolved oxygen supply is a limiting factor, which influences yield, product quality and production cost. To solve this problem, we intended to heterologously express VHb in P. lilacinus ACSS. After optimizing the vgb gene, we fused it with a selection marker gene nptII, a promoter PgpdA and a terminator TtrpC. The complete expression cassette PgpdA-nptII-vgb-TtrpC was transferred into P. lilacinus ACSS by Agrobacterium tumefaciens-mediated transformation. Consequently, we successfully screened an applicable fungus strain PNVT8 which efficiently expressed VHb. The submerged fermentation experiments demonstrated that the expression of VHb not only increased the production traits of P. lilacinus such as biomass and spore production, but also improved the beneficial product quality and application value, due to the secretion of more protease and chitinase. It can be speculated that the recombinant strain harboring vgb gene will have a growth advantage over the original strain under anaerobic conditions in soil and therefore will possess higher biocontrol efficiency against plant-parasitic nematodes. Copyright © 2014 Elsevier B.V. All rights reserved.
FGF-2 deficiency does not influence FGF ligand and receptor expression during development of the nigrostriatal system.

PubMed

Ratzka, Andreas; Baron, Olga; Grothe, Claudia

2011-01-01

Secreted proteins of the fibroblast growth factor (FGF) family play important roles during development of various organ systems. A detailed knowledge of their temporal and spatial expression profiles, especially of closely related FGF family members, are essential to further identification of specific functions in distinct tissues. In the central nervous system dopaminergic neurons of the substantia nigra and their axonal projections into the striatum progressively degenerate in Parkinson's disease. In contrast, FGF-2 deficient mice display increased numbers of dopaminergic neurons. In this study, we determined the expression profiles of all 22 FGF-ligands and 10 FGF-receptor isoforms, in order to clarify, if FGF-2 deficiency leads to compensatory up-regulation of other FGFs in the nigrostriatal system. Three tissues, ventral mesencephalon (VM), striatum (STR) and as reference tissue spinal cord (SC) of wild-type and FGF-2 deficient mice at four developmental stages E14.5, P0, P28, and adult were comparatively analyzed by quantitative RT-PCR. As no differences between the genotypes were observed, a compensatory up-regulation can be excluded. Moreover, this analysis revealed that the majority of FGF-ligands (18/22) and FGF-receptors (9/10) are expressed during normal development of the nigrostriatal system and identified dynamic changes for some family members. By comparing relative expression level changes to SC reference tissue, general alterations in all 3 tissues, such as increased expression of FGF-1, -2, -22, FgfR-2c, -3c and decreased expression of FGF-13 during postnatal development were identified. Further, specific changes affecting only one tissue, such as increased FGF-16 (STR) or decreased FGF-17 (VM) expression, or two tissues, such as decreased expression of FGF-8 (VM, STR) and FGF-15 (SC, VM) were found. Moreover, 3 developmentally down-regulated FGFs (FGF-8b, FGF-15, FGF-17a) were functionally characterized by plasmid-based over-expression in
Systems Biophysics of Gene Expression

PubMed Central

Vilar, Jose M.G.; Saiz, Leonor

2013-01-01

Gene expression is a process central to any form of life. It involves multiple temporal and functional scales that extend from specific protein-DNA interactions to the coordinated regulation of multiple genes in response to intracellular and extracellular changes. This diversity in scales poses fundamental challenges to the use of traditional approaches to fully understand even the simplest gene expression systems. Recent advances in computational systems biophysics have provided promising avenues to reliably integrate the molecular detail of biophysical process into the system behavior. Here, we review recent advances in the description of gene regulation as a system of biophysical processes that extend from specific protein-DNA interactions to the combinatorial assembly of nucleoprotein complexes. There is now basic mechanistic understanding on how promoters controlled by multiple, local and distal, DNA binding sites for transcription factors can actively control transcriptional noise, cell-to-cell variability, and other properties of gene regulation, including precision and flexibility of the transcriptional responses. PMID:23790365
Tombusvirus-based vector systems to permit over-expression of genes or that serve as sensors of antiviral RNA silencing in plants.

PubMed

Shamekova, Malika; Mendoza, Maria R; Hsieh, Yi-Cheng; Lindbo, John; Omarov, Rustem T; Scholthof, Herman B

2014-03-01

A next generation Tomato bushy stunt virus (TBSV) coat protein gene replacement vector system is described that can be applied by either RNA inoculation or through agroinfiltration. A vector expressing GFP rapidly yields high levels of transient gene expression in inoculated leaves of various plant species, as illustrated for Nicotiana benthamiana, cowpea, tomato, pepper, and lettuce. A start-codon mutation to down-regulate the dose of the P19 silencing suppressor reduces GFP accumulation, whereas mutations that result in undetectable levels of P19 trigger rapid silencing of GFP. Compared to existing virus vectors the TBSV system has a unique combination of a very broad host range, rapid and high levels of replication and gene expression, and the ability to regulate its suppressor. These features are attractive for quick transient assays in numerous plant species for over-expression of genes of interest, or as a sensor to monitor the efficacy of antiviral RNA silencing. Copyright © 2014. Published by Elsevier Inc.
Expression of Arabidopsis glycine-rich RNA-binding protein AtGRP2 or AtGRP7 improves grain yield of rice (Oryza sativa) under drought stress conditions.

PubMed

Yang, Deok Hee; Kwak, Kyung Jin; Kim, Min Kyung; Park, Su Jung; Yang, Kwang-Yeol; Kang, Hunseung

2014-01-01

Although posttranscriptional regulation of RNA metabolism is increasingly recognized as a key regulatory process in plant response to environmental stresses, reports demonstrating the importance of RNA metabolism control in crop improvement under adverse environmental stresses are severely limited. To investigate the potential use of RNA-binding proteins (RBPs) in developing stress-tolerant transgenic crops, we generated transgenic rice plants (Oryza sativa) that express Arabidopsis thaliana glycine-rich RBP (AtGRP) 2 or 7, which have been determined to harbor RNA chaperone activity and confer stress tolerance in Arabidopsis, and analyzed the response of the transgenic rice plants to abiotic stresses. AtGRP2- or AtGRP7-expressing transgenic rice plants displayed similar phenotypes comparable with the wild-type plants under high salt or cold stress conditions. By contrast, AtGRP2- or AtGRP7-expressing transgenic rice plants showed much higher recovery rates and grain yields compared with the wild-type plants under drought stress conditions. The higher grain yield of the transgenic rice plants was due to the increases in filled grain numbers per panicle. Collectively, the present results show the importance of posttranscriptional regulation of RNA metabolism in plant response to environmental stress and suggest that GRPs can be utilized to improve the yield potential of crops under stress conditions. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Pyramiding genes and alleles for improving energy cane biomass yield

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

Ming, Ray; Nagai, Chifumi; Yu, Qingyi

The overall goal of this project is to identify genes and gene interaction networks contributed to the extreme segregants with 30 folds biomass yield difference in sugarcane F2 populations. Towards achieving this goal, yield trials of 108 F2 extreme segregants from S. officinarum LA Purple and S. robustum MOL5829 (LM population) were carried out in two locations in three years. A yield trial of the second F2 population from S. officinarum LA Purple and S. spontaneum US56-14-4 (LU population) was installed in the summer of 2014 and the first set of yield component data was collected. For genotyping, transcriptomes frommore » leaves and stalks of 70 extreme segregants of the LM F2 population and 119 individuals of the LU F2 populations were sequenced. The genomes of 91 F1 individuals from the LM populations are being sequenced to construct ultra-high density genetic maps for each of the two parents for both assisting the LA Purple genome assembling and for testing a hypothesis of female restitution. The genomes of 110 F2 individuals from single F1 in the LU population, a different set from the 119 F2 individuals used for transcriptome sequencing, are being sequenced for mapping genes and QTLs affecting biomass yield and for testing a hypothesis of female restitution. Gene expression analysis between extreme segregants of high and low biomass yield showed up-regulation of cellulose synthase, cellulose, and xylan synthase in high biomass yield segregants among 3,274 genes differentially expressed between the two extremes. Our transcriptome results revealed not only the increment of cell wall biosynthesis pathway is essential, but the rapid turnover of certain cell wall polymers as well as carbohydrate partitioning are also important for recycling and energy conservation during rapid cell growth in high biomass sugarcane. Seventeen differentially expressed genes in auxin, one in ethylene and one in gibberellin related signaling and biosynthesis pathways were
Development of a European Ensemble System for Seasonal Prediction: Application to crop yield

NASA Astrophysics Data System (ADS)

Terres, J. M.; Cantelaube, P.

2003-04-01

Western European agriculture is highly intensive and the weather is the main source of uncertainty for crop yield assessment and for crop management. In the current system, at the time when a crop yield forecast is issued, the weather conditions leading up to harvest time are unknown and are therefore a major source of uncertainty. The use of seasonal weather forecast would bring additional information for the remaining crop season and has valuable benefit for improving the management of agricultural markets and environmentally sustainable farm practices. An innovative method for supplying seasonal forecast information to crop simulation models has been developed in the frame of the EU funded research project DEMETER. It consists in running a crop model on each individual member of the seasonal hindcasts to derive a probability distribution of crop yield. Preliminary results of cumulative probability function of wheat yield provides information on both the yield anomaly and the reliability of the forecast. Based on the spread of the probability distribution, the end-user can directly quantify the benefits and risks of taking weather-sensitive decisions.
Development and validation of equations utilizing lamb vision system output to predict lamb carcass fabrication yields.

PubMed

Cunha, B C N; Belk, K E; Scanga, J A; LeValley, S B; Tatum, J D; Smith, G C

2004-07-01

This study was performed to validate previous equations and to develop and evaluate new regression equations for predicting lamb carcass fabrication yields using outputs from a lamb vision system-hot carcass component (LVS-HCC) and the lamb vision system-chilled carcass LM imaging component (LVS-CCC). Lamb carcasses (n = 149) were selected after slaughter, imaged hot using the LVS-HCC, and chilled for 24 to 48 h at -3 to 1 degrees C. Chilled carcasses yield grades (YG) were assigned on-line by USDA graders and by expert USDA grading supervisors with unlimited time and access to the carcasses. Before fabrication, carcasses were ribbed between the 12th and 13th ribs and imaged using the LVS-CCC. Carcasses were fabricated into bone-in subprimal/primal cuts. Yields calculated included 1) saleable meat yield (SMY); 2) subprimal yield (SPY); and 3) fat yield (FY). On-line (whole-number) USDA YG accounted for 59, 58, and 64%; expert (whole-number) USDA YG explained 59, 59, and 65%; and expert (nearest-tenth) USDA YG accounted for 60, 60, and 67% of the observed variation in SMY, SPY, and FY, respectively. The best prediction equation developed in this trial using LVS-HCC output and hot carcass weight as independent variables explained 68, 62, and 74% of the variation in SMY, SPY, and FY, respectively. Addition of output from LVS-CCC improved predictive accuracy of the equations; the combined output equations explained 72 and 66% of the variability in SMY and SPY, respectively. Accuracy and repeatability of measurement of LM area made with the LVS-CCC also was assessed, and results suggested that use of LVS-CCC provided reasonably accurate (R2 = 0.59) and highly repeatable (repeatability = 0.98) measurements of LM area. Compared with USDA YG, use of the dual-component lamb vision system to predict cut yields of lamb carcasses improved accuracy and precision, suggesting that this system could have an application as an objective means for pricing carcasses in a value
Differential expression of CURS gene during various growth stages, climatic condition and soil nutrients in turmeric (Curcuma longa): Towards site specific cultivation for high curcumin yield.

PubMed

Sandeep, I Sriram; Das, Suryasnata; Nasim, Noohi; Mishra, Antaryami; Acharya, Laxmikanta; Joshi, Raj Kumar; Nayak, Sanghamitra; Mohanty, Sujata

2017-09-01

Curcuma longa L., accumulates substantial amount of curcumin and essential oil. Little is known about the differential expression of curcumin synthase (CURS) gene and consequent curcumin content variations at different agroclimatic zones. The present study aimed to evaluate the effect of climate, soil and harvesting phase on expression of CURS gene for curcumin yield in two high yielding turmeric cultivars. Expression of CURS gene at different experimental zones as well as at different harvesting phase was studied through transcriptional analysis by qRT-PCR. Curcumin varied from 1.5 to 5% and 1.4-5% in Surama and Roma respectively. The expression of CURS also varied from 0.402 to 5.584 fold in Surama and 0.856-5.217 fold in Roma. Difference in curcumin content at a particular zone varied among different harvesting period from 3.95 to 4.31% in Surama and 3.57-3.83% in Roma. Expression of CURS gene was also effected by harvesting time of the rhizome which varied from 7.389 to 16.882 fold in Surama and 4.41-8.342 fold in Roma. The CURS gene expression was found regardless of variations in curcumin content at different experimental zones. This may be due to the effects of soil and environmental variables. Expression was positively correlated with curcumin content with different harvesting time at a particular zone. This find indicates effect of soil and environment on molecular and biochemical dynamics of curcumin biosynthesis and could be useful in genetic improvement of turmeric. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Gene expression systems in corynebacteria.

PubMed

Srivastava, Preeti; Deb, J K

2005-04-01

Corynebacterium belongs to a group of gram-positive bacteria having moderate to high G+C content, the other members being Mycobacterium, Nocardia, and Rhodococcus. Considerable information is now available on the plasmids, gene regulatory elements, and gene expression in corynebacteria, especially in soil corynebacteria such as Corynebacterium glutamicum. These bacteria are non-pathogenic and, unlike Bacillus and Streptomyces, are low in proteolytic activity and thus have the potential of becoming attractive systems for expression of heterologous proteins. This review discusses recent advances in our understanding of the organization of various regulatory elements, such as promoters, transcription terminators, and development of vectors for cloning and gene expression.
High-yield expression and purification of isotopically labeled cytochrome P450 monooxygenases for solid-state NMR spectroscopy

PubMed Central

Rupasinghe, Sanjeewa G.; Duan, Hui; Frericks Schmidt, Heather L.; Berthold, Deborah A.; Rienstra, Chad M.; Schuler, Mary A.

2008-01-01

Cytochrome P450 monooxygenases (P450s), which represent the major group of drug metabolizing enzymes in humans, also catalyze important synthetic and detoxicative reactions in insects, plants and many microbes. Flexibilities in their catalytic sites and membrane associations are thought to play central roles in substrate binding and catalytic specificity. To date, E. coli expression strategies for structural analysis of eukaryotic membrane-bound P450s by X-ray crystallography have necessitated full or partial removal of their N-terminal signal anchor domain (SAD) and, often, replacement of residues more peripherally associated with the membrane (such as the F-G loop region). Even with these modifications, investigations of P450 structural flexibility remain challenging with multiple single crystal conditions needed to identify spatial variations between substrate-free and different substrate-bound forms. To overcome these limitations, we have developed methods for the efficient expression of 13C- and 15N-labeled P450s and analysis of their structures by magic-angle spinning solid-state NMR (SSNMR) spectroscopy. In the presence of co-expressed GroEL and GroES chaperones, full-length (53 kDa) Arabidopsis 13C,15N-labeled CYP98A3 is expressed at yields of 2–4 mg per liter of minimal media without the necessity of generating side chain modifications or N-terminal deletions. Precipitated CYP98A3 generates high quality SSNMR spectra consistent with a homogeneous, folded protein. These data highlight the potential of these methodologies to contribute to the structural analysis of membrane-bound proteins. PMID:18005930
Implementation of the agmatine-controlled expression system for inducible gene expression in Lactococcus lactis.

PubMed

Linares, Daniel M; Alvarez-Sieiro, Patricia; del Rio, Beatriz; Ladero, Victor; Redruello, Begoña; Martin, Ma Cruz; Fernandez, Maria; Alvarez, Miguel A

2015-12-30

Lactococcus lactis has been safely consumed in fermented foods for millennia. This Gram-positive bacterium has now become of industrial importance as an expression host for the overproduction of lipopolysaccharide-free recombinant proteins used as food ingredients, therapeutic proteins and biotechnological enzymes. This paper reports an agmatine-controlled expression (ACE) system for L. lactis, comprising the lactococcal agmatine-sensor/transcriptional activator AguR and its target promoter P(aguB). The usefulness and efficiency of this system was checked via the reporter gene gfp and by producing PEP (Myxococcus xanthus prolyl-endopeptidase), an enzyme of biomedical interest able to degrade the immunotoxic peptides produced during the gastrointestinal breakdown of gluten. The ACE system developed in this work was suitable for the efficient expression of the functional recombinant proteins GFP and PEP. The expression system was tightly regulated by the agmatine concentration and allowed high protein production without leakiness.

Absolute gene expression patterns of thioredoxin and glutaredoxin redox systems in mouse.

PubMed

Jurado, Juan; Prieto-Alamo, María-José; Madrid-Rísquez, José; Pueyo, Carmen

2003-11-14

This work provides the first absolute expression patterns of genes coding for all known components of both thioredoxin (Trx) and glutaredoxin (Grx) systems in mouse: Trx1, Trx2, Grx1, Grx2, TrxR1, TrxR2, thioredoxin/glutathione reductase, and glutathione reductase. We devised a novel assay that, combining the advantages of multiplex and real-time PCR, streamlines the quantitation of the actual mRNA copy numbers in whole-animal experiments. Quantitations reported establish differences among adult organs and embryonic stages, compare mRNA decay rates, explore the significance of alternative mRNA isoforms derived from TrxR1 and Grx2 genes, and examine the time-course expression upon superoxide stress promoted by paraquat. Collectively, these quantitations show: i) unique expression profiles for each transcript and mouse organ examined, yet with some general trends like the higher amounts of mRNA species coding for thioredoxins than those coding for the reductases that control their redox states and activities; ii) continuous expression during embryogenesis with outstanding up-regulations of Trx1 and TrxR1 mRNAs in specific temporal sequences; iii) drastic differences in mRNA stability, liver decay rates range from 2.8 h (thioredoxin/glutathione reductase) to >/= 35 h (Trx1 and Trx2), and directly correlate with mRNA steady-state values; iv) testis-specific differences in the amounts (relative to total isoforms) of transcripts yielding the mitochondrial Grx2a and 67-kDa TrxR1 variants; and v) coordinated up-regulation of TrxR1 and glutathione reductase mRNAs in response to superoxide stress in an organ-specific manner. Further insights into in vivo roles of these redox systems should be gained from more focused studies of the mechanisms underlying the vast differences reported here at the transcript level.
An evaluation of the lamb vision system as a predictor of lamb carcass red meat yield percentage.

PubMed

Brady, A S; Belk, K E; LeValley, S B; Dalsted, N L; Scanga, J A; Tatum, J D; Smith, G C

2003-06-01

An objective method for predicting red meat yield in lamb carcasses is needed to accurately assess true carcass value. This study was performed to evaluate the ability of the lamb vision system (LVS; Research Management Systems USA, Fort Collins, CO) to predict fabrication yields of lamb carcasses. Lamb carcasses (n = 246) were evaluated using LVS and hot carcass weight (HCW), as well as by USDA expert and on-line graders, before fabrication of carcass sides to either bone-in or boneless cuts. On-line whole number, expert whole-number, and expert nearest-tenth USDA yield grades and LVS + HCW estimates accounted for 53, 52, 58, and 60%, respectively, of the observed variability in boneless, saleable meat yields, and accounted for 56, 57, 62, and 62%, respectively, of the variation in bone-in, saleable meat yields. The LVS + HCW system predicted 77, 65, 70, and 87% of the variation in weights of boneless shoulders, racks, loins, and legs, respectively, and 85, 72, 75, and 86% of the variation in weights of bone-in shoulders, racks, loins, and legs, respectively. Addition of longissimus muscle area (REA), adjusted fat thickness (AFT), or both REA and AFT to LVS + HCW models resulted in improved prediction of boneless saleable meat yields by 5, 3, and 5 percentage points, respectively. Bone-in, saleable meat yield estimations were improved in predictive accuracy by 7.7, 6.6, and 10.1 percentage points, and in precision, when REA alone, AFT alone, or both REA and AFT, respectively, were added to the LVS + HCW output models. Use of LVS + HCW to predict boneless red meat yields of lamb carcasses was more accurate than use of current on-line whole-number, expert whole-number, or expert nearest-tenth USDA yield grades. Thus, LVS + HCW output, when used alone or in combination with AFT and/or REA, improved on-line estimation of boneless cut yields from lamb carcasses. The ability of LVS + HCW to predict yields of wholesale cuts suggests that LVS could be used as an objective
Identifying seedling root architectural traits associated with yield and yield components in wheat.

PubMed

Xie, Quan; Fernando, Kurukulasuriya M C; Mayes, Sean; Sparkes, Debbie L

2017-05-01

Plant roots growing underground are critical for soil resource acquisition, anchorage and plant-environment interactions. In wheat ( Triticum aestivum ), however, the target root traits to improve yield potential still remain largely unknown. This study aimed to identify traits of seedling root system architecture (RSA) associated with yield and yield components in 226 recombinant inbred lines (RILs) derived from a cross between the bread wheat Triticum aestivum 'Forno' (small, wide root system) and spelt Triticum spelta 'Oberkulmer' (large, narrow root system). A 'pouch and wick' high-throughput phenotyping pipeline was used to determine the RSA traits of 13-day-old RIL seedlings. Two field experiments and one glasshouse experiment were carried out to investigate the yield, yield components and phenology, followed by identification of quantitative trait loci (QTLs). There was substantial variation in RSA traits between genotypes. Seminal root number and total root length were both positively associated with grains m -2 , grains per spike, above-ground biomass m -2 and grain yield. More seminal roots and longer total root length were also associated with delayed maturity and extended grain filling, likely to be a consequence of more grains being defined before anthesis. Additionally, the maximum width of the root system displayed positive relationships with spikes m -2 , grains m -2 and grain yield. Ten RILs selected for the longest total roots exhibited the same effects on yield and phenology as described above, compared with the ten lines with the shortest total roots. Genetic analysis revealed 38 QTLs for the RSA, and QTL coincidence between the root and yield traits was frequently observed, indicating tightly linked genes or pleiotropy, which concurs with the results of phenotypic correlation analysis. Based on the results from the Forno × Oberkulmer population, it is proposed that vigorous early root growth, particularly more seminal roots and longer total
High yield cell-free production of integral membrane proteins without refolding or detergents.

PubMed

Wuu, Jessica J; Swartz, James R

2008-05-01

Integral membrane proteins act as critical cellular components and are important drug targets. However, difficulties in producing membrane proteins have hampered investigations of structure and function. In vivo production systems are often limited by cell toxicity, and previous in vitro approaches have required unnatural folding pathways using detergents or lipid solutions. To overcome these limitations, we present an improved cell-free expression system which produces high yields of integral membrane proteins without the use of detergents or refolding steps. Our cell-free reaction activates an Escherichia coli-derived cell extract for transcription and translation. Purified E. coli inner membrane vesicles supply membrane-bound components and the lipid environment required for insertion and folding. Using this system, we demonstrated successful synthesis of two complex integral membrane transporters, the tetracycline pump (TetA) and mannitol permease (MtlA), in yields of 570+/-50 microg/mL and 130+/-30 microg/mL of vesicle-associated protein, respectively. These yields are up to 400 times typical in vivo concentrations. Insertion and folding of these proteins are verified by sucrose flotation, protease digestion, and activity assays. Whereas TetA incorporates efficiently into vesicle membranes with over two-thirds of the synthesized protein being inserted, MtlA yields appear to be limited by insufficient concentrations of a membrane-associated chaperone.
Integrating remote sensing, geographic information system and modeling for estimating crop yield

NASA Astrophysics Data System (ADS)

Salazar, Luis Alonso

This thesis explores various aspects of the use of remote sensing, geographic information system and digital signal processing technologies for broad-scale estimation of crop yield in Kansas. Recent dry and drought years in the Great Plains have emphasized the need for new sources of timely, objective and quantitative information on crop conditions. Crop growth monitoring and yield estimation can provide important information for government agencies, commodity traders and producers in planning harvest, storage, transportation and marketing activities. The sooner this information is available the lower the economic risk translating into greater efficiency and increased return on investments. Weather data is normally used when crop yield is forecasted. Such information, to provide adequate detail for effective predictions, is typically feasible only on small research sites due to expensive and time-consuming collections. In order for crop assessment systems to be economical, more efficient methods for data collection and analysis are necessary. The purpose of this research is to use satellite data which provides 50 times more spatial information about the environment than the weather station network in a short amount of time at a relatively low cost. Specifically, we are going to use Advanced Very High Resolution Radiometer (AVHRR) based vegetation health (VH) indices as proxies for characterization of weather conditions.
YorkieCA overexpression in the posterior silk gland improves silk yield in Bombyx mori.

PubMed

Zhang, Panli; Liu, Shumin; Song, Hong-Sheng; Zhang, Guozheng; Jia, Qiangqiang; Li, Sheng

2017-07-01

The traditional hybrid breeding techniques can no longer meet the increasing demands for silk production by the silkworm, Bombyx mori, and further improvement of the silk yield will depend on modern molecular breeding techniques. Here, we report improved silk yield in transgenic silkworms overexpressing the oncogene Yorkie CA specifically in the posterior silk gland (PSG). The Yorkie CA cDNA was ligated downstream of the hr3 enhancer and the fibroin L-chain (Fil) promoter, then inserted into a piggyBac vector for transgene. Overexpression of Yorkie CA in the PSG significantly increased the weight of the PSG, and also increased the weight of the cocoon, larval body, and pupal body to decreasing degrees. Overexpression of Yorkie CA up-regulated the Yorkie target genes resulting in increased cell size, endomitosis, the number of protein synthesis organelles, the expression of fibroin genes in the PSG, and eventually silk yield. Additionally, as we reported previously using the binary GAL4/UAS system, transgenic silkworms overexpressing Ras1 CA with the hr3 enhancer and the Fil promoter also showed improved silk yield. Unfortunately, the hybrid progeny of Yorkie CA -overexpressing silkworms and Ras1 CA -overexpressing silkworms did not show overlapping improved silk yield due to the failure to increase expression of both Yorkie and Ras1. Copyright © 2017. Published by Elsevier Ltd.
Enhanced Furfural Yields from Xylose Dehydration in the gamma-Valerolactone/Water Solvent System at Elevated Temperatures.

PubMed

Sener, Canan; Motagamwala, Ali Hussain; Alonso, David Martin; Dumesic, James

2018-05-18

High yields of furfural (>90%) were achieved from xylose dehydration in a sustainable solvent system composed of -valerolactone (GVL), a biomass derived solvent, and water. It is identified that high reaction temperatures (e.g., 498 K) are required to achieve high furfural yield. Additionally, it is shown that the furfural yield at these temperatures is independent of the initial xylose concentration, and high furfural yield is obtained for industrially relevant xylose concentrations (10 wt%). A reaction kinetics model is developed to describe the experimental data obtained with solvent system composed of 80 wt% GVL and 20 wt% water across the range of reaction conditions studied (473 - 523 K, 1-10 mM acid catalyst, 66 - 660 mM xylose concentration). The kinetic model demonstrates that furfural loss due to bimolecular condensation of xylose and furfural is minimized at elevated temperature, whereas carbon loss due to xylose degradation increases with increasing temperature. Accordingly, the optimal temperature range for xylose dehydration to furfural in the GVL/H2O solvent system is identified to be from 480 to 500 K. Under these reaction conditions, furfural yield of 93% is achieved at 97% xylan conversion from lignocellulosic biomass (maple wood). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Study on paddy rice yield estimation based on multisource data and the Grey system theory

NASA Astrophysics Data System (ADS)

Deng, Wensheng; Wang, Wei; Liu, Hai; Li, Chen; Ge, Yimin; Zheng, Xianghua

2009-10-01

The paddy rice is our important crops. In study of the paddy rice yield estimation, compared with the scholars who usually only take the remote sensing data or meteorology as the influence factors, we combine the remote sensing and the meteorological data to make the monitoring result closer reality. Although the gray system theory has used in many aspects, it is applied very little in paddy rice yield estimation. This study introduces it to the paddy rice yield estimation, and makes the yield estimation model. This can resolve small data sets problem that can not be solved by deterministic model. It selects some regions in Jianghan plain for the study area. The data includes multi-temporal remote sensing image, meteorological and statistic data. The remote sensing data is the 16-day composite images (250-m spatial resolution) of MODIS. The meteorological data includes monthly average temperature, sunshine duration and rain fall amount. The statistical data is the long-term paddy rice yield of the study area. Firstly, it extracts the paddy rice planting area from the multi-temporal MODIS images with the help of GIS and RS. Then taking the paddy rice yield as the reference sequence, MODIS data and meteorological data as the comparative sequence, computing the gray correlative coefficient, it selects the yield estimation factor based on the grey system theory. Finally, using the factors, it establishes the yield estimation model and does the result test. The result indicated that the method is feasible and the conclusion is credible. It can provide the scientific method and reference value to carry on the region paddy rice remote sensing estimation.
Estimating the potential intensification of global grazing systems based on climate adjusted yield gap analysis

NASA Astrophysics Data System (ADS)

Sheehan, J. J.

2016-12-01

We report here a first-of-its-kind analysis of the potential for intensification of global grazing systems. Intensification is calculated using the statistical yield gap methodology developed previously by others (Mueller et al 2012 and Licker et al 2010) for global crop systems. Yield gaps are estimated by binning global pasture land area into 100 equal area sized bins of similar climate (defined by ranges of rainfall and growing degree days). Within each bin, grid cells of pastureland are ranked from lowest to highest productivity. The global intensification potential is defined as the sum of global production across all bins at a given percentile ranking (e.g. performance at the 90th percentile) divided by the total current global production. The previous yield gap studies focused on crop systems because productivity data on these systems is readily available. Nevertheless, global crop land represents only one-third of total global agricultural land, while pasture systems account for the remaining two-thirds. Thus, it is critical to conduct the same kind of analysis on what is the largest human use of land on the planet—pasture systems. In 2013, Herrero et al announced the completion of a geospatial data set that augmented the animal census data with data and modeling about production systems and overall food productivity (Herrero et al, PNAS 2013). With this data set, it is now possible to apply yield gap analysis to global pasture systems. We used the Herrero et al data set to evaluate yield gaps for meat and milk production from pasture based systems for cattle, sheep and goats. The figure included with this abstract shows the intensification potential for kcal per hectare per year of meat and milk from global cattle, sheep and goats as a function of increasing levels of performance. Performance is measured as the productivity achieved at a given ranked percentile within each bin.We find that if all pasture land were raised to their 90th percentile of
Interpretation of quantum yields exceeding unity in photoelectrochemical systems

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

Szklarczyk, M.; Allen, R.E.

1986-10-20

In photoelectrochemical systems involving light shining on a semiconductor interfaced with an electrolyte, the quantum yield as a function of photon frequency ..nu.. is observed to exhibit a peak at h..nu..roughly-equal2E/sub g/, where E/sub g/ is the band gap of the semiconductor. The maximum in this peak is sometimes found to exceed unity. We provide an interpretation involving surface states and inelastic electron-electron scattering. The theory indicates that the effect should be observable for p-type semiconductors, but not n-type.
Efficient system of artificial oil bodies for functional expression and purification of recombinant nattokinase in Escherichia coli.

PubMed

Chiang, Chung-Jen; Chen, Hong-Chen; Chao, Yun-Peng; Tzen, Jason T C

2005-06-15

Nattokinase, a serine protease, and pronattokinase, when expressed in Escherichia coli, formed insoluble aggregates without enzymatic activity. For functional expression and purification, nattokinase or pronattokinase was first overexpressed in E. coli as an insoluble recombinant protein linked to the C terminus of oleosin, a structural protein of seed oil bodies, by an intein fragment. Artificial oil bodies were reconstituted with triacylglycerol, phospholipid, and the insoluble recombinant protein thus formed. Soluble nattokinase was subsequently released through self-splicing of intein induced by temperature alteration, with the remaining oleosin-intein residing in oil bodies and the leading propeptide of pronattokinase, when present, spontaneously cleaved in the process. Active nattokinase with fibrinolytic activity was harvested by concentrating the supernatant. Nattokinase released from oleosin-intein-pronattokinase exhibited 5 times higher activity than that released from oleosin-intein-nattokinase, although the production yields were similar in both cases. Furthermore, active nattokinase could be harvested in the same system by fusing pronattokinase to the N terminus of oleosin via a different intein linker, with self-splicing induced by 1,4-dithiothreitol. These results have shown a great potential of this system for bacterial expression and purification of functional recombinant proteins.
Grain yield response to poultry litter application under a wheat-soybean double cropping system

USDA-ARS?s Scientific Manuscript database

Poultry litter application and double cropping are management practices that could be used with conservation tillage systems to increase yields compared to conventional monocropping systems. The objective of this study was to evaluate wheat (Triticum aestivum L.) and soybean [Glycine max (L.) Merr.]...
Satellite-based assessment of yield variation and its determinants in smallholder African systems

PubMed Central

Lobell, David B.

2017-01-01

The emergence of satellite sensors that can routinely observe millions of individual smallholder farms raises possibilities for monitoring and understanding agricultural productivity in many regions of the world. Here we demonstrate the potential to track smallholder maize yield variation in western Kenya, using a combination of 1-m Terra Bella imagery and intensive field sampling on thousands of fields over 2 y. We find that agreement between satellite-based and traditional field survey-based yield estimates depends significantly on the quality of the field-based measures, with agreement highest (R2 up to 0.4) when using precise field measures of plot area and when using larger fields for which rounding errors are smaller. We further show that satellite-based measures are able to detect positive yield responses to fertilizer and hybrid seed inputs and that the inferred responses are statistically indistinguishable from estimates based on survey-based yields. These results suggest that high-resolution satellite imagery can be used to make predictions of smallholder agricultural productivity that are roughly as accurate as the survey-based measures traditionally used in research and policy applications, and they indicate a substantial near-term potential to quickly generate useful datasets on productivity in smallholder systems, even with minimal or no field training data. Such datasets could rapidly accelerate learning about which interventions in smallholder systems have the most positive impact, thus enabling more rapid transformation of rural livelihoods. PMID:28202728
Satellite-based assessment of yield variation and its determinants in smallholder African systems.

PubMed

Burke, Marshall; Lobell, David B

2017-02-28

The emergence of satellite sensors that can routinely observe millions of individual smallholder farms raises possibilities for monitoring and understanding agricultural productivity in many regions of the world. Here we demonstrate the potential to track smallholder maize yield variation in western Kenya, using a combination of 1-m Terra Bella imagery and intensive field sampling on thousands of fields over 2 y. We find that agreement between satellite-based and traditional field survey-based yield estimates depends significantly on the quality of the field-based measures, with agreement highest ([Formula: see text] up to 0.4) when using precise field measures of plot area and when using larger fields for which rounding errors are smaller. We further show that satellite-based measures are able to detect positive yield responses to fertilizer and hybrid seed inputs and that the inferred responses are statistically indistinguishable from estimates based on survey-based yields. These results suggest that high-resolution satellite imagery can be used to make predictions of smallholder agricultural productivity that are roughly as accurate as the survey-based measures traditionally used in research and policy applications, and they indicate a substantial near-term potential to quickly generate useful datasets on productivity in smallholder systems, even with minimal or no field training data. Such datasets could rapidly accelerate learning about which interventions in smallholder systems have the most positive impact, thus enabling more rapid transformation of rural livelihoods.
[Advance of heterologous expression study of eukaryote-origin laccases].

PubMed

Ning, Na; Tan, Huijun; Sun, Xinxin; Ni, Jinfeng

2017-04-25

Laccases are enzymes belonging to the group of multi-copper oxidases. These enzymes are widely distributed in insects, plants, fungi and bacteria. In general, laccases can oxidize an exceptionally high number of substrates, so they have broad applications in textile, pulp, food and the degradation of lignin. However, low yield, low activity and thermo-instability of laccase in nature limit the application of laccase. High efficient heterologous expression of the protein is an effective way for solving this problem. Here, we summarize the research advances of heterologous expression of eukaryote-origin laccases. We focus on the overexpression of eukaryote-origin laccases using different expression system and the method for improving the production yield and enzyme activity in yeast cells. Information provided in this review would be helpful for researchers in the field.
Yield and economic performance of organic and conventional cotton-based farming systems--results from a field trial in India.

PubMed

Forster, Dionys; Andres, Christian; Verma, Rajeev; Zundel, Christine; Messmer, Monika M; Mäder, Paul

2013-01-01

The debate on the relative benefits of conventional and organic farming systems has in recent time gained significant interest. So far, global agricultural development has focused on increased productivity rather than on a holistic natural resource management for food security. Thus, developing more sustainable farming practices on a large scale is of utmost importance. However, information concerning the performance of farming systems under organic and conventional management in tropical and subtropical regions is scarce. This study presents agronomic and economic data from the conversion phase (2007-2010) of a farming systems comparison trial on a Vertisol soil in Madhya Pradesh, central India. A cotton-soybean-wheat crop rotation under biodynamic, organic and conventional (with and without Bt cotton) management was investigated. We observed a significant yield gap between organic and conventional farming systems in the 1(st) crop cycle (cycle 1: 2007-2008) for cotton (-29%) and wheat (-27%), whereas in the 2(nd) crop cycle (cycle 2: 2009-2010) cotton and wheat yields were similar in all farming systems due to lower yields in the conventional systems. In contrast, organic soybean (a nitrogen fixing leguminous plant) yields were marginally lower than conventional yields (-1% in cycle 1, -11% in cycle 2). Averaged across all crops, conventional farming systems achieved significantly higher gross margins in cycle 1 (+29%), whereas in cycle 2 gross margins in organic farming systems were significantly higher (+25%) due to lower variable production costs but similar yields. Soybean gross margin was significantly higher in the organic system (+11%) across the four harvest years compared to the conventional systems. Our results suggest that organic soybean production is a viable option for smallholder farmers under the prevailing semi-arid conditions in India. Future research needs to elucidate the long-term productivity and profitability, particularly of cotton and
Climatically driven yield variability of major crops in Khakassia (South Siberia)

NASA Astrophysics Data System (ADS)

Babushkina, Elena A.; Belokopytova, Liliana V.; Zhirnova, Dina F.; Shah, Santosh K.; Kostyakova, Tatiana V.

2018-06-01

We investigated the variability of yield of the three main crop cultures in the Khakassia Republic: spring wheat, spring barley, and oats. In terms of yield values, variability characteristics, and climatic response, the agricultural territory of Khakassia can be divided into three zones: (1) the Northern Zone, where crops yield has a high positive response to the amount of precipitation, May-July, and a moderately negative one to the temperatures of the same period; (2) the Central Zone, where crops yield depends mainly on temperatures; and (3) the Southern Zone, where climate has the least expressed impact on yield. The dominant pattern in the crops yield is caused by water stress during periods of high temperatures and low moisture supply with heat stress as additional reason. Differences between zones are due to combinations of temperature latitudinal gradient, precipitation altitudinal gradient, and the presence of a well-developed hydrological network and the irrigational system as moisture sources in the Central Zone. More detailed analysis shows differences in the climatic sensitivity of crops during phases of their vegetative growth and grain development and, to a lesser extent, during harvesting period. Multifactor linear regression models were constructed to estimate climate- and autocorrelation-induced variability of the crops yield. These models allowed prediction of the possibility of yield decreasing by at least 2-11% in the next decade due to increasing of the regional summer temperatures.
Climatically driven yield variability of major crops in Khakassia (South Siberia)

NASA Astrophysics Data System (ADS)

Babushkina, Elena A.; Belokopytova, Liliana V.; Zhirnova, Dina F.; Shah, Santosh K.; Kostyakova, Tatiana V.

2017-12-01

We investigated the variability of yield of the three main crop cultures in the Khakassia Republic: spring wheat, spring barley, and oats. In terms of yield values, variability characteristics, and climatic response, the agricultural territory of Khakassia can be divided into three zones: (1) the Northern Zone, where crops yield has a high positive response to the amount of precipitation, May-July, and a moderately negative one to the temperatures of the same period; (2) the Central Zone, where crops yield depends mainly on temperatures; and (3) the Southern Zone, where climate has the least expressed impact on yield. The dominant pattern in the crops yield is caused by water stress during periods of high temperatures and low moisture supply with heat stress as additional reason. Differences between zones are due to combinations of temperature latitudinal gradient, precipitation altitudinal gradient, and the presence of a well-developed hydrological network and the irrigational system as moisture sources in the Central Zone. More detailed analysis shows differences in the climatic sensitivity of crops during phases of their vegetative growth and grain development and, to a lesser extent, during harvesting period. Multifactor linear regression models were constructed to estimate climate- and autocorrelation-induced variability of the crops yield. These models allowed prediction of the possibility of yield decreasing by at least 2-11% in the next decade due to increasing of the regional summer temperatures.
Proposal of Self-Learning and Recognition System of Facial Expression

NASA Astrophysics Data System (ADS)

Ogawa, Yukihiro; Kato, Kunihito; Yamamoto, Kazuhiko

We describe realization of more complicated function by using the information acquired from some equipped unripe functions. The self-learning and recognition system of the human facial expression, which achieved under the natural relation between human and robot, are proposed. The robot with this system can understand human facial expressions and behave according to their facial expressions after the completion of learning process. The system modelled after the process that a baby learns his/her parents’ facial expressions. Equipping the robot with a camera the system can get face images and equipping the CdS sensors on the robot’s head the robot can get the information of human action. Using the information of these sensors, the robot can get feature of each facial expression. After self-learning is completed, when a person changed his facial expression in front of the robot, the robot operates actions under the relevant facial expression.
Dual Luciferase Assay System for Rapid Assessment of Gene Expression in Saccharomyces cerevisiae

PubMed Central

McNabb, David S.; Reed, Robin; Marciniak, Robert A.

2005-01-01

A new reporter system has been developed for quantifying gene expression in the yeast Saccharomyces cerevisiae. The system relies on two different reporter genes, Renilla and firefly luciferase, to evaluate regulated gene expression. The gene encoding Renilla luciferase is fused to a constitutive promoter (PGK1 or SPT15) and integrated into the yeast genome at the CAN1 locus as a control for normalizing the assay. The firefly luciferase gene is fused to the test promoter and integrated into the yeast genome at the ura3 or leu2 locus. The dual luciferase assay is performed by sequentially measuring the firefly and Renilla luciferase activities of the same sample, with the results expressed as the ratio of firefly to Renilla luciferase activity (Fluc/Rluc). The yeast dual luciferase reporter (DLR) was characterized and shown to be very efficient, requiring approximately 1 minute to complete each assay, and has proven to yield data that accurately and reproducibly reflect promoter activity. A series of integrating plasmids were generated that contain either the firefly or Renilla luciferase gene preceded by a multicloning region in two different orientations and the three reading frames to make possible the generation of translational fusions. Additionally, each set of plasmids contains either the URA3 or LEU2 marker for genetic selection in yeast. A series of S288C-based yeast strains, including a two-hybrid strain, were developed to facilitate the use of the yeast DLR assay. This assay can be readily adapted to a high-throughput platform for studies requiring numerous measurements. PMID:16151247

Chapter 15. transforming lepidopteran insect cells for continuous recombinant protein expression

USDA-ARS?s Scientific Manuscript database

The baculovirus expression vector system (BEVS) is widely used to produce large quantities of recombinant proteins. However, yields of extracellular and membrane-bound proteins obtained with this system often are very low, possibly due to the adverse effects of baculovirus infection on the host ins...
Transgenic Arabidopsis Gene Expression System

NASA Technical Reports Server (NTRS)

Ferl, Robert; Paul, Anna-Lisa

2009-01-01

The Transgenic Arabidopsis Gene Expression System (TAGES) investigation is one in a pair of investigations that use the Advanced Biological Research System (ABRS) facility. TAGES uses Arabidopsis thaliana, thale cress, with sensor promoter-reporter gene constructs that render the plants as biomonitors (an organism used to determine the quality of the surrounding environment) of their environment using real-time nondestructive Green Fluorescent Protein (GFP) imagery and traditional postflight analyses.
The Expression of TaRca2-α Gene Associated with Net Photosynthesis Rate, Biomass and Grain Yield in Bread Wheat (Triticum aestivum L.) under Field Conditions

PubMed Central

Saeed, Iqbal; Bachir, Daoura Goudia; Chen, Liang; Hu, Yin-Gang

2016-01-01

Improvement in activation of Rubisco by Rubisco activase can potentially enhance CO2 assimilation and photosynthetic efficiency in plants. The three homoeologous copies of TaRca2-α were identified on chromosomes 4AL, 4BS and 4DS (TaRca2-α-4AL, TaRca2-α-4BS, and TaRca2-α-4DS) in bread wheat. Expression patterns of the three copies at heading (Z55), anthesis (Z67) and grain-filling (Z73) stages were investigated through qRT-PCR analyses in a panel of 59 bread wheat genotypes and their effects on net photosynthesis rate (Pn), biomass plant-1 (BMPP) and grain yield plant-1 (GYPP) were further explored. Different but similar expression patterns were observed for the three copies of TaRca2-α at the three growth stages with highest expression at grain-filling stage. TaRca2-α-4BS expressed higher at the three stages than TaRca2-α-4AL and TaRca2-α-4DS. The 59 genotypes could be clustered into three groups as high (7 genotypes), intermediate (41 genotypes) and low (11 genotypes) expression based on the expression of the three copies of TaRca2-α at three growth stages. Significant variations (P<0.01) were observed among the three groups of bread wheat genotypes for Pn, BMPP and GYPP. Generally, the genotypes with higher TaRca2-α expression also showed higher values for Pn, BMPP and GYPP. The expressions of the three copies of TaRca2-α at heading, anthesis and grain-filling stages were positively correlated with Pn, BMPP and GYPP (P<0.01) with stronger association for TaRca2-α-4BS at grain-filling stage. These results revealed that the expression of TaRca2-α contribute substantially to Pn, BMPP and GYPP, and suggested that manipulating TaRca-α expression may efficiently improve Pn, BMPP and GYPP in bread wheat and detecting TaRca-α expression levels with emphasis on TaRca2-α-4BS may be a positive strategy for selection in improving photosynthetic efficiency and grain yield of bread wheat. PMID:27548477
Cellulases for biomass degradation: comparing recombinant cellulase expression platforms.

PubMed

Garvey, Megan; Klose, Holger; Fischer, Rainer; Lambertz, Camilla; Commandeur, Ulrich

2013-10-01

Improvement of cellulase expression has the potential to change the nature of the biofuel industry. Increasing the economic feasibility of cellulase systems would significantly broaden the range of practicable biomass conversion, lowering the environmental impact of our civilisations' fuel needs. Cellulases are derived from certain fungi and bacteria, which are often difficult to culture on an industrial scale. Accordingly, methods to recombinantly express important cellulases and other glycosyl hydrolase (GH) enzymes are under serious investigation. Herein, we examine the latest developments in bacterial, yeast, plant, and fungal expression systems. We discuss current strategies for producing cellulases, and evaluate the benefits and drawbacks in yield, stability, and activity of enzymes from each system, and the overall progress in the field. Copyright © 2013 Elsevier Ltd. All rights reserved.
Human Ocular Epithelial Cells Endogenously Expressing SOX2 and OCT4 Yield High Efficiency of Pluripotency Reprogramming.

PubMed

Poon, Ming-Wai; He, Jia; Fang, Xiaowei; Zhang, Zhao; Wang, Weixin; Wang, Junwen; Qiu, Fangfang; Tse, Hung-Fat; Li, Wei; Liu, Zuguo; Lian, Qizhou

2015-01-01

A variety of pluripotency reprogramming frequencies from different somatic cells has been observed, indicating cell origin is a critical contributor for efficiency of pluripotency reprogramming. Identifying the cell sources for efficient induced pluripotent stem cells (iPSCs) generation, and defining its advantages or disadvantages on reprogramming, is therefore important. Human ocular tissue-derived conjunctival epithelial cells (OECs) exhibited endogenous expression of reprogramming factors OCT4A (the specific OCT 4 isoform on pluripotency reprogramming) and SOX2. We therefore determined whether OECs could be used for high efficiency of iPSCs generation. We compared the endogenous expression levels of four pluripotency factors and the pluripotency reprograming efficiency of human OECs with that of ocular stromal cells (OSCs). Real-time PCR, microarray analysis, Western blotting and immunostaining assays were employed to compare OECiPSCs with OSCiPSCs on molecular bases of reprogramming efficiency and preferred lineage-differentiation potential. Using the traditional KMOS (KLF4, C-MYC, OCT4 and SOX2) reprogramming protocol, we confirmed that OECs, endogenously expressing reprogramming factors OCT4A and SOX2, yield very high efficiency of iPSCs generation (~1.5%). Furthermore, higher efficiency of retinal pigmented epithelial differentiation (RPE cells) was observed in OECiPSCs compared to OSCiPSCs or skin fibroblast iMR90iPSCs. The findings in this study suggest that conjunctival-derived epithelial (OECs) cells can be easier converted to iPSCs than conjunctival-derived stromal cells (OSCs). This cell type may also have advantages in retinal pigmented epithelial differentiation.
Expression and purification of the matrix protein of Nipah virus in baculovirus insect cell system.

PubMed

Masoomi Dezfooli, Seyedehsara; Tan, Wen Siang; Tey, Beng Ti; Ooi, Chien Wei; Hussain, Siti Aslina

2016-01-01

Nipah virus (NiV) causes fatal respiratory illness and encephalitis in humans and animals. The matrix (M) protein of NiV plays an important role in the viral assembly and budding process. Thus, an access to the NiV M protein is vital to the design of viral antigens as diagnostic reagents. In this study, recombinant DNA technology was successfully adopted in the cloning and expression of NiV M protein. A recombinant expression cassette (baculovirus expression vector) was used to encode an N-terminally His-tagged NiV M protein in insect cells. A time-course study demonstrated that the highest yield of recombinant M protein (400-500 μg) was expressed from 107 infected cells 3 days after infection. A single-step purification method based on metal ion affinity chromatography was established to purify the NiV M protein, which successfully yielded a purity level of 95.67% and a purification factor of 3.39. The Western blotting and enzyme-linked immunosorbent assay (ELISA) showed that the purified recombinant M protein (48 kDa) was antigenic and reacted strongly with the serum of a NiV infected pig. © 2015 American Institute of Chemical Engineers.
The Z {yields} cc-bar {yields} {gamma}{gamma}*, Z {yields} bb-bar {yields} {gamma}{gamma}* triangle diagrams and the Z {yields} {gamma}{psi}, Z {yields} {gamma}Y decays

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

Achasov, N. N., E-mail: achasov@math.nsc.ru

2011-03-15

The approach to the Z {yields} {gamma}{psi} and Z {yields} {gamma}Y decay study is presented in detail, based on the sum rules for the Z {yields} cc-bar {yields} {gamma}{gamma}* and Z {yields} bb-bar {yields} {gamma}{gamma}* amplitudes and their derivatives. The branching ratios of the Z {yields} {gamma}{psi} and Z {yields} {gamma}Y decays are calculated for different hypotheses on saturation of the sum rules. The lower bounds of {Sigma}{sub {psi}} BR(Z {yields} {gamma}{psi}) = 1.95 Multiplication-Sign 10{sup -7} and {Sigma}{sub {upsilon}} BR(Z {yields} {gamma}Y) = 7.23 Multiplication-Sign 10{sup -7} are found. Deviations from the lower bounds are discussed, including the possibilitymore » of BR(Z {yields} {gamma}J/{psi}(1S)) {approx} BR(Z {yields} {gamma}Y(1S)) {approx} 10{sup -6}, that could be probably measured in LHC. The angular distributions in the Z {yields} {gamma}{psi} and Z {yields} {gamma}Y decays are also calculated.« less
OsPIN5b modulates rice (Oryza sativa) plant architecture and yield by changing auxin homeostasis, transport and distribution.

PubMed

Lu, Guangwen; Coneva, Viktoriya; Casaretto, José A; Ying, Shan; Mahmood, Kashif; Liu, Fang; Nambara, Eiji; Bi, Yong-Mei; Rothstein, Steven J

2015-09-01

Plant architecture attributes such as tillering, plant height and panicle size are important agronomic traits that determine rice (Oryza sativa) productivity. Here, we report that altered auxin content, transport and distribution affect these traits, and hence rice yield. Overexpression of the auxin efflux carrier-like gene OsPIN5b causes pleiotropic effects, mainly reducing plant height, leaf and tiller number, shoot and root biomass, seed-setting rate, panicle length and yield parameters. Conversely, reduced expression of OsPIN5b results in higher tiller number, more vigorous root system, longer panicles and increased yield. We show that OsPIN5b is an endoplasmic reticulum (ER) -localized protein that participates in auxin homeostasis, transport and distribution in vivo. This work describes an example of an auxin-related gene where modulating its expression can simultaneously improve plant architecture and yield potential in rice, and reveals an important effect of hormonal signaling on these traits. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.
Evaluation of detergents for the soluble expression of alpha-helical and beta-barrel-type integral membrane proteins by a preparative scale individual cell-free expression system.

PubMed

Klammt, Christian; Schwarz, Daniel; Fendler, Klaus; Haase, Winfried; Dötsch, Volker; Bernhard, Frank

2005-12-01

Cell-free expression has become a highly promising tool for the fast and efficient production of integral membrane proteins. The proteins can be produced as precipitates that solubilize in mild detergents usually without any prior denaturation steps. Alternatively, membrane proteins can be synthesized in a soluble form by adding detergents to the cell-free system. However, the effects of a representative variety of detergents on the production, solubility and activity of a wider range of membrane proteins upon cell-free expression are currently unknown. We therefore analyzed the cell-free expression of three structurally very different membrane proteins, namely the bacterial alpha-helical multidrug transporter, EmrE, the beta-barrel nucleoside transporter, Tsx, and the porcine vasopressin receptor of the eukaryotic superfamily of G-protein coupled receptors. All three membrane proteins could be produced in amounts of several mg per one ml of reaction mixture. In general, the detergent 1-myristoyl-2-hydroxy-sn-glycero-3-[phospho-rac-(1-glycerol)] was found to be most effective for the resolubilization of membrane protein precipitates, while long chain polyoxyethylene-alkyl-ethers proved to be most suitable for the soluble expression of all three types of membrane proteins. The yield of soluble expressed membrane protein remained relatively stable above a certain threshold concentration of the detergents. We report, for the first time, the high-level cell-free expression of a beta-barrel type membrane protein in a functional form. Structural and functional variations of the analyzed membrane proteins are evident that correspond with the mode of expression and that depend on the supplied detergent.
Facial expression system on video using widrow hoff

NASA Astrophysics Data System (ADS)

Jannah, M.; Zarlis, M.; Mawengkang, H.

2018-03-01

Facial expressions recognition is one of interesting research. This research contains human feeling to computer application Such as the interaction between human and computer, data compression, facial animation and facial detection from the video. The purpose of this research is to create facial expression system that captures image from the video camera. The system in this research uses Widrow-Hoff learning method in training and testing image with Adaptive Linear Neuron (ADALINE) approach. The system performance is evaluated by two parameters, detection rate and false positive rate. The system accuracy depends on good technique and face position that trained and tested.
Gene expression profiling in multipotent DFAT cells derived from mature adipocytes

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

Ono, Hiromasa; Database Center for Life Science; Oki, Yoshinao

2011-04-15

Highlights: {yields} Adipocyte dedifferentiation is evident in a significant decrease in typical genes. {yields} Cell proliferation is strongly related to adipocyte dedifferentiation. {yields} Dedifferentiated adipocytes express several lineage-specific genes. {yields} Comparative analyses using publicly available datasets boost the interpretation. -- Abstract: Cellular dedifferentiation signifies the withdrawal of cells from a specific differentiated state to a stem cell-like undifferentiated state. However, the mechanism of dedifferentiation remains obscure. Here we performed comparative transcriptome analyses during dedifferentiation in mature adipocytes (MAs) to identify the transcriptional signatures of multipotent dedifferentiated fat (DFAT) cells derived from MAs. Using microarray systems, we explored similarly expressed asmore » well as significantly differentially expressed genes in MAs during dedifferentiation. This analysis revealed significant changes in gene expression during this process, including a significant reduction in expression of genes for lipid metabolism concomitantly with a significant increase in expression of genes for cell movement, cell migration, tissue developmental processes, cell growth, cell proliferation, cell morphogenesis, altered cell shape, and cell differentiation. Our observations indicate that the transcriptional signatures of DFAT cells derived from MAs are summarized in terms of a significant decrease in functional phenotype-related genes and a parallel increase in cell proliferation, altered cell morphology, and regulation of the differentiation of related genes. A better understanding of the mechanisms involved in dedifferentiation may enable scientists to control and possibly alter the plasticity of the differentiated state, which may lead to benefits not only in stem cell research but also in regenerative medicine.« less
21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cardiac allograft gene expression profiling test... Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system. (a) Identification. A cardiac allograft gene expression profiling test system is a device that measures the...
Homologous expression of cytosolic dehydroascorbate reductase increases grain yield and biomass under paddy field conditions in transgenic rice (Oryza sativa L. japonica).

PubMed

Kim, Young-Saeng; Kim, Il-Sup; Bae, Mi-Jung; Choe, Yong-Hoe; Kim, Yul-Ho; Park, Hyang-Mi; Kang, Hong-Gyu; Yoon, Ho-Sung

2013-06-01

Dehydroascorbate reductase (DHAR, EC 1.8.5.1) maintains redox pools of ascorbate (AsA) by recycling oxidized AsA to reduced AsA. To investigate whether DHAR affects rice yield under normal environmental conditions, cDNA-encoding DHAR (OsDHAR1) was isolated from rice and used to develop OsDHAR1-overexpressing transgenic rice plants, under the regulation of a maize ubiquitin promoter. Incorporation and expression of the transgene in transgenic rice plants was confirmed by genomic polymerase chain reaction (PCR), semi-quantitative reverse transcription PCR (RT-PCR), western blot, and enzyme activity. The expression levels were at least twofold higher in transgenic (TG) rice plants than in control wild-type (WT) rice plants. In addition, OsDHAR1-overexpression in seven-independent homologous transgenic plants, as compared to WT plants, increased photosynthetic capacity and antioxidant enzyme activities under paddy field conditions, which led to an improved AsA pool and redox homeostasis. Furthermore, OsDHAR1 overexpression significantly improved grain yield and biomass due to the increase of culm and root weights and to enhance panicle and spikelet numbers in the same seven independent TG rice plants during the farming season (2010 and 2011) in South Korea. The OsDHAR protein contained the redox-active site (Cys20), as well as the conserved GSH-binding region, GSH-binding motif, glutathione-S-transferase (GST) N-terminal domain, C-terminal domain interface, and GST C-terminal domain. Therefore, our results indicate that OsDHAR1 overexpression, capable of functioning in AsA recycling, and protein folding increases environmental adaptation to paddy field conditions by the improving AsA pool and redox homeostasis, which enhances rice grain yield and biomass.
Recombinant protein expression for structural biology in HEK 293F suspension cells: a novel and accessible approach.

PubMed

Portolano, Nicola; Watson, Peter J; Fairall, Louise; Millard, Christopher J; Milano, Charles P; Song, Yun; Cowley, Shaun M; Schwabe, John W R

2014-10-16

The expression and purification of large amounts of recombinant protein complexes is an essential requirement for structural biology studies. For over two decades, prokaryotic expression systems such as E. coli have dominated the scientific literature over costly and less efficient eukaryotic cell lines. Despite the clear advantage in terms of yields and costs of expressing recombinant proteins in bacteria, the absence of specific co-factors, chaperones and post-translational modifications may cause loss of function, mis-folding and can disrupt protein-protein interactions of certain eukaryotic multi-subunit complexes, surface receptors and secreted proteins. The use of mammalian cell expression systems can address these drawbacks since they provide a eukaryotic expression environment. However, low protein yields and high costs of such methods have until recently limited their use for structural biology. Here we describe a simple and accessible method for expressing and purifying milligram quantities of protein by performing transient transfections of suspension grown HEK (Human Embryonic Kidney) 293 F cells.
Subplots facilitate assessment of corn yield losses from weed competition in a long-term systems experiment

USDA-ARS?s Scientific Manuscript database

Weeds can potentially limit crop yield, particularly in organic systems where herbicide technologies are unavailable. Weedy and weed-free subplots were established within full plots of a long-term cropping systems experiment, the Farming Systems Project, at Beltsville, Maryland, USA, to determine t...
Expression of the Nitrate Transporter Gene OsNRT1.1A/OsNPF6.3 Confers High Yield and Early Maturation in Rice.

PubMed

Wang, Wei; Hu, Bin; Yuan, Dingyang; Liu, Yongqiang; Che, Ronghui; Hu, Yingchun; Ou, Shujun; Liu, Yongxin; Zhang, Zhihua; Wang, Hongru; Li, Hua; Jiang, Zhimin; Zhang, Zhengli; Gao, Xiaokai; Qiu, Yahong; Meng, Xiangbing; Liu, Yongxin; Bai, Yang; Liang, Yan; Wang, Yiqin; Zhang, Lianhe; Li, Legong; Sodmergen; Jing, Haichun; Li, Jiayang; Chu, Chengcai

2018-03-01

Nitrogen (N) is a major driving force for crop yield improvement, but application of high levels of N delays flowering, prolonging maturation and thus increasing the risk of yield losses. Therefore, traits that enable utilization of high levels of N without delaying maturation will be highly desirable for crop breeding. Here, we show that OsNRT1.1A (OsNPF6.3), a member of the rice ( Oryza sativa ) nitrate transporter 1/peptide transporter family, is involved in regulating N utilization and flowering, providing a target to produce high yield and early maturation simultaneously. OsNRT.1A has functionally diverged from previously reported NRT1.1 genes in plants and functions in upregulating the expression of N utilization-related genes not only for nitrate but also for ammonium, as well as flowering-related genes. Relative to the wild type, osnrt1.1a mutants exhibited reduced N utilization and late flowering. By contrast, overexpression of OsNRT1.1A in rice greatly improved N utilization and grain yield, and maturation time was also significantly shortened. These effects were further confirmed in different rice backgrounds and also in Arabidopsis thaliana Our study paves a path for the use of a single gene to dramatically increase yield and shorten maturation time for crops, outcomes that promise to substantially increase world food security. © 2018 American Society of Plant Biologists. All rights reserved.
Maximum sustainable yield and species extinction in a prey-predator system: some new results.

PubMed

Ghosh, Bapan; Kar, T K

2013-06-01

Though the maximum sustainable yield (MSY) approach has been legally adopted for the management of world fisheries, it does not provide any guarantee against from species extinction in multispecies communities. In the present article, we describe the appropriateness of the MSY policy in a Holling-Tanner prey-predator system with different types of functional responses. It is observed that for both type I and type II functional responses, harvesting of either prey or predator species at the MSY level is a sustainable fishing policy. In the case of combined harvesting, both the species coexist at the maximum sustainable total yield (MSTY) level if the biotic potential of the prey species is greater than a threshold value. Further, increase of the biotic potential beyond the threshold value affects the persistence of the system.
High-level HIV-1 Nef transient expression in Nicotiana benthamiana using the P19 gene silencing suppressor protein of Artichoke Mottled Crinckle Virus

PubMed Central

2009-01-01

Background In recent years, different HIV antigens have been successfully expressed in plants by either stable transformation or transient expression systems. Among HIV proteins, Nef is considered a promising target for the formulation of a multi-component vaccine due to its implication in the first steps of viral infection. Attempts to express Nef as a single protein product (not fused to a stabilizing protein) in transgenic plants resulted in disappointingly low yields (about 0.5% of total soluble protein). In this work we describe a transient expression system based on co-agroinfiltration of plant virus gene silencing suppressor proteins in Nicotiana benthamiana, followed by a two-step affinity purification protocol of plant-derived Nef. Results The effect of three gene silencing viral suppressor proteins (P25 of Potato Virus X, P19 of either Artichoke Mottled Crinckle virus and Tomato Bushy Stunt virus) on Nef transient expression yield was evaluated. The P19 protein of Artichoke Mottled Crinckle virus (AMCV-P19) gave the highest expression yield in vacuum co-agroinfiltration experiments reaching 1.3% of total soluble protein, a level almost three times higher than that previously reported in stable transgenic plants. The high yield observed in the co-agroinfiltrated plants was correlated to a remarkable decrease of Nef-specific small interfering RNAs (siRNAs) indicating an effective modulation of RNA silencing mechanisms by AMCV-P19. Interestingly, we also showed that expression levels in top leaves of vacuum co-agroinfiltrated plants were noticeably reduced compared to bottom leaves. Moreover, purification of Nef from agroinfiltrated tissue was achieved by a two-step immobilized metal ion affinity chromatography protocol with yields of 250 ng/g of fresh tissue. Conclusion We demonstrated that expression level of HIV-1 Nef in plant can be improved using a transient expression system enhanced by the AMCV-P19 gene silencing suppressor protein. Moreover, plant
High-level HIV-1 Nef transient expression in Nicotiana benthamiana using the P19 gene silencing suppressor protein of Artichoke Mottled Crinckle Virus.

PubMed

Lombardi, Raffaele; Circelli, Patrizia; Villani, Maria Elena; Buriani, Giampaolo; Nardi, Luca; Coppola, Valentina; Bianco, Linda; Benvenuto, Eugenio; Donini, Marcello; Marusic, Carla

2009-11-20

In recent years, different HIV antigens have been successfully expressed in plants by either stable transformation or transient expression systems. Among HIV proteins, Nef is considered a promising target for the formulation of a multi-component vaccine due to its implication in the first steps of viral infection. Attempts to express Nef as a single protein product (not fused to a stabilizing protein) in transgenic plants resulted in disappointingly low yields (about 0.5% of total soluble protein). In this work we describe a transient expression system based on co-agroinfiltration of plant virus gene silencing suppressor proteins in Nicotiana benthamiana, followed by a two-step affinity purification protocol of plant-derived Nef. The effect of three gene silencing viral suppressor proteins (P25 of Potato Virus X, P19 of either Artichoke Mottled Crinckle virus and Tomato Bushy Stunt virus) on Nef transient expression yield was evaluated. The P19 protein of Artichoke Mottled Crinckle virus (AMCV-P19) gave the highest expression yield in vacuum co-agroinfiltration experiments reaching 1.3% of total soluble protein, a level almost three times higher than that previously reported in stable transgenic plants. The high yield observed in the co-agroinfiltrated plants was correlated to a remarkable decrease of Nef-specific small interfering RNAs (siRNAs) indicating an effective modulation of RNA silencing mechanisms by AMCV-P19. Interestingly, we also showed that expression levels in top leaves of vacuum co-agroinfiltrated plants were noticeably reduced compared to bottom leaves. Moreover, purification of Nef from agroinfiltrated tissue was achieved by a two-step immobilized metal ion affinity chromatography protocol with yields of 250 ng/g of fresh tissue. We demonstrated that expression level of HIV-1 Nef in plant can be improved using a transient expression system enhanced by the AMCV-P19 gene silencing suppressor protein. Moreover, plant-derived Nef was purified, with
Destiny-yield relationship for channel catfish reared in a biofloc technology production system

USDA-ARS?s Scientific Manuscript database

The effect of stocking density on yield of stocker channel catfish and water quality in a biofloc technology production system was studied in this completely randomized design experiment. Fingerling channel catfish (Ictalurus punctatus; 48.0 g/fish, 17.8 cm/fish) were stocked into nine continuously ...

Expression of the Nitrate Transporter Gene OsNRT1.1A/OsNPF6.3 Confers High Yield and Early Maturation in Rice[OPEN

PubMed Central

Wang, Wei; Hu, Bin; Liu, Yongqiang; Che, Ronghui; Hu, Yingchun; Zhang, Zhihua; Wang, Hongru; Li, Hua; Jiang, Zhimin; Zhang, Zhengli; Gao, Xiaokai; Qiu, Yahong; Meng, Xiangbing; Liu, Yongxin; Bai, Yang; Liang, Yan; Wang, Yiqin; Zhang, Lianhe; Li, Legong; Sodmergen; Jing, Haichun

2018-01-01

Nitrogen (N) is a major driving force for crop yield improvement, but application of high levels of N delays flowering, prolonging maturation and thus increasing the risk of yield losses. Therefore, traits that enable utilization of high levels of N without delaying maturation will be highly desirable for crop breeding. Here, we show that OsNRT1.1A (OsNPF6.3), a member of the rice (Oryza sativa) nitrate transporter 1/peptide transporter family, is involved in regulating N utilization and flowering, providing a target to produce high yield and early maturation simultaneously. OsNRT.1A has functionally diverged from previously reported NRT1.1 genes in plants and functions in upregulating the expression of N utilization-related genes not only for nitrate but also for ammonium, as well as flowering-related genes. Relative to the wild type, osnrt1.1a mutants exhibited reduced N utilization and late flowering. By contrast, overexpression of OsNRT1.1A in rice greatly improved N utilization and grain yield, and maturation time was also significantly shortened. These effects were further confirmed in different rice backgrounds and also in Arabidopsis thaliana. Our study paves a path for the use of a single gene to dramatically increase yield and shorten maturation time for crops, outcomes that promise to substantially increase world food security. PMID:29475937
The separation distance distribution in electron-donor-acceptor systems and the wavelength dependence of free ion yields

NASA Astrophysics Data System (ADS)

Zhou, Jinwei; Findley, Bret R.; Braun, Charles L.; Sutin, Norman

2001-06-01

We recently reported that free radical ion quantum yields for electron-donor-acceptor (EDA) systems of alkylbenzenes-tetracyanoethylene (TCNE) exhibit a remarkable wavelength dependence in dichloromethane, a medium polarity solvent. We proposed that weak absorption by long-distance, unassociated or "random" D⋯A pairs is mainly responsible for the free radical ion yield. Here a model for the wavelength dependence of the free ion yield is developed for four systems in which differing degrees of EDA complex formation are present: 1,3,5-tri-tert-butylbenzene-TCNE in which only random pairs exist due to the bulky groups on the electron donor, and toluene—TCNE, 1,3,5-triethylbenzene-TCNE and 1,3,5-trimethylbenzene-TCNE. Mulliken-Hush theory is used to determine the excitation distance distribution of unassociated, random pairs at different wavelengths. For each absorption distribution, free radical ion yields at different wavelengths are then calculated using Onsager's result for the ion separation probability. Encouraging agreement between the calculated yields and our experimental results is obtained. As far as we are aware, this is the first time that photoexcitation of unassociated donor/acceptor pairs has been invoked as the source of separated radical ion pairs.
Fission yield and criticality excursion code

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

Blanchard, A.

2000-06-30

The ANSI/ANS 8.3 standard allows a maximum yield not to exceed 2 x 10 fissions to calculate requiring the alarm system to be effective. It is common practice to use this allowance or to develop some other yield based on past criticality accident history or excursion experiments. The literature on the subject of yields discusses maximum yields larger and somewhat smaller than the ANS 8.3 permissive value. The ability to model criticality excursions and vary the various parameters to determine a credible maximum yield for operational specific cases has been available for some time but is not in common usemore » by criticality safety specialists. The topic of yields for various solution, metal, oxide powders, etc. in various geometry's and containers has been published by laboratory specialists or university staff and students for many decades but have not been available to practitioners. The need for best-estimate calculations of fission yields with a well-validated criticality excursion code has long been recognized. But no coordinated effort has been made so far to develop a generalized and well-validated excursion code for different types of systems. In this paper, the current practices to estimate fission yields are summarized along with its shortcomings for the 12-Rad zone (at SRS) and Criticality Alarm System (CAS) calculations. Finally the need for a user-friendly excursion code is reemphasized.« less
Cell-Free Optogenetic Gene Expression System.

PubMed

Jayaraman, Premkumar; Yeoh, Jing Wui; Jayaraman, Sudhaghar; Teh, Ai Ying; Zhang, Jingyun; Poh, Chueh Loo

2018-04-20

Optogenetic tools provide a new and efficient way to dynamically program gene expression with unmatched spatiotemporal precision. To date, their vast potential remains untapped in the field of cell-free synthetic biology, largely due to the lack of simple and efficient light-switchable systems. Here, to bridge the gap between cell-free systems and optogenetics, we studied our previously engineered one component-based blue light-inducible Escherichia coli promoter in a cell-free environment through experimental characterization and mathematical modeling. We achieved >10-fold dynamic expression and demonstrated rapid and reversible activation of the target gene to generate oscillatory response. The deterministic model developed was able to recapitulate the system behavior and helped to provide quantitative insights to optimize dynamic response. This in vitro optogenetic approach could be a powerful new high-throughput screening technology for rapid prototyping of complex biological networks in both space and time without the need for chemical induction.
A quality assessment of the MARS crop yield forecasting system for the European Union

NASA Astrophysics Data System (ADS)

van der Velde, Marijn; Bareuth, Bettina

2015-04-01

Timely information on crop production forecasts can become of increasing importance as commodity markets are more and more interconnected. Impacts across large crop production areas due to (e.g.) extreme weather and pest outbreaks can create ripple effects that may affect food prices and availability elsewhere. The MARS Unit (Monitoring Agricultural ResourceS), DG Joint Research Centre, European Commission, has been providing forecasts of European crop production levels since 1993. The operational crop production forecasting is carried out with the MARS Crop Yield Forecasting System (M-CYFS). The M-CYFS is used to monitor crop growth development, evaluate short-term effects of anomalous meteorological events, and provide monthly forecasts of crop yield at national and European Union level. The crop production forecasts are published in the so-called MARS bulletins. Forecasting crop yield over large areas in the operational context requires quality benchmarks. Here we present an analysis of the accuracy and skill of past crop yield forecasts of the main crops (e.g. soft wheat, grain maize), throughout the growing season, and specifically for the final forecast before harvest. Two simple benchmarks to assess the skill of the forecasts were defined as comparing the forecasts to 1) a forecast equal to the average yield and 2) a forecast using a linear trend established through the crop yield time-series. These reveal a variability in performance as a function of crop and Member State. In terms of production, the yield forecasts of 67% of the EU-28 soft wheat production and 80% of the EU-28 maize production have been forecast superior to both benchmarks during the 1993-2013 period. In a changing and increasingly variable climate crop yield forecasts can become increasingly valuable - provided they are used wisely. We end our presentation by discussing research activities that could contribute to this goal.
Expression of an Arabidopsis molybdenum cofactor sulphurase gene in soybean enhances drought tolerance and increases yield under field conditions.

PubMed

Li, Yajun; Zhang, Jiachang; Zhang, Juan; Hao, Ling; Hua, Jinping; Duan, Liusheng; Zhang, Mingcai; Li, Zhaohu

2013-08-01

LOS5/ABA3 gene encoding molybdenum cofactor sulphurase is involved in aldehyde oxidase (AO) activity in Arabidopsis, which indirectly regulates ABA biosynthesis and increased stress tolerance. Here, we used a constitutive super promoter to drive LOS5/ABA3 overexpression in soybean (Glycine max L.) to enhance drought tolerance in growth chamber and field conditions. Expression of LOS5/ABA3 was up-regulated by drought stress, which led to increasing AO activity and then a notable increase in ABA accumulation. Transgenic soybean under drought stress had reduced water loss by decreased stomatal aperture size and transpiration rate, which alleviated leaf wilting and maintained higher relative water content. Exposed to drought stress, transgenic soybean exhibited reduced cell membrane damage by reducing electrolyte leakage and production of malondialdehyde and promoting proline accumulation and antioxidant enzyme activities. Also, overexpression of LOS5/ABA3 enhanced expression of stress-up-regulated genes. Furthermore, the seed yield of transgenic plants is at least 21% higher than that of wide-type plants under drought stress conditions in the field. These data suggest that overexpression of LOS5/ABA3 could improve drought tolerance in transgenic soybean via enhanced ABA accumulation, which could activate expression of stress-up-regulated genes and cause a series of physiological and biochemical resistant responses. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.
Fungal Gene Expression on Demand: an Inducible, Tunable, and Metabolism-Independent Expression System for Aspergillus niger▿†

PubMed Central

Meyer, Vera; Wanka, Franziska; van Gent, Janneke; Arentshorst, Mark; van den Hondel, Cees A. M. J. J.; Ram, Arthur F. J.

2011-01-01

Filamentous fungi are the cause of serious human and plant diseases but are also exploited in biotechnology as production platforms. Comparative genomics has documented their genetic diversity, and functional genomics and systems biology approaches are under way to understand the functions and interaction of fungal genes and proteins. In these approaches, gene functions are usually inferred from deletion or overexpression mutants. However, studies at these extreme points give only limited information. Moreover, many overexpression studies use metabolism-dependent promoters, often causing pleiotropic effects and thus limitations in their significance. We therefore established and systematically evaluated a tunable expression system for Aspergillus niger that is independent of carbon and nitrogen metabolism and silent under noninduced conditions. The system consists of two expression modules jointly targeted to a defined genomic locus. One module ensures constitutive expression of the tetracycline-dependent transactivator rtTA2S-M2, and one module harbors the rtTA2S-M2-dependent promoter that controls expression of the gene of interest (the Tet-on system). We show here that the system is tight, responds within minutes after inducer addition, and allows fine-tuning based on the inducer concentration or gene copy number up to expression levels higher than the expression levels of the gpdA promoter. We also validate the Tet-on system for the generation of conditional overexpression mutants and demonstrate its power when combined with a gene deletion approach. Finally, we show that the system is especially suitable when the functions of essential genes must be examined. PMID:21378046
Secretory production of a beta-mannanase and a chitosanase using a Lactobacillus plantarum expression system.

PubMed

Sak-Ubol, Suttipong; Namvijitr, Peenida; Pechsrichuang, Phornsiri; Haltrich, Dietmar; Nguyen, Thu-Ha; Mathiesen, Geir; Eijsink, Vincent G H; Yamabhai, Montarop

2016-05-12

Heterologous production of hydrolytic enzymes is important for green and white biotechnology since these enzymes serve as efficient biocatalysts for the conversion of a wide variety of raw materials into value-added products. Lactic acid bacteria are interesting cell factories for the expression of hydrolytic enzymes as many of them are generally recognized as safe and require only a simple cultivation process. We are studying a potentially food-grade expression system for secretion of hydrolytic enzymes into the culture medium, since this enables easy harvesting and purification, while allowing direct use of the enzymes in food applications. We studied overexpression of a chitosanase (CsnA) and a β-mannanase (ManB), from Bacillus licheniformis and Bacillus subtilis, respectively, in Lactobacillus plantarum, using the pSIP system for inducible expression. The enzymes were over-expressed in three forms: without a signal peptide, with their natural signal peptide and with the well-known OmpA signal peptide from Escherichia coli. The total production levels and secretion efficiencies of CsnA and ManB were highest when using the native signal peptides, and both were reduced considerably when using the OmpA signal. At 20 h after induction with 12.5 ng/mL of inducing peptide in MRS media containing 20 g/L glucose, the yields and secretion efficiencies of the proteins with their native signal peptides were 50 kU/L and 84% for ManB, and 79 kU/L and 56% for CsnA, respectively. In addition, to avoid using antibiotics, the erythromycin resistance gene was replaced on the expression plasmid with the alanine racemase (alr) gene, which led to comparable levels of protein production and secretion efficiency in a suitable, alr-deficient L. plantarum host. ManB and CsnA were efficiently produced and secreted in L. plantarum using pSIP-based expression vectors containing either an erythromycin resistance or the alr gene as selection marker.
Yield and Economic Performance of Organic and Conventional Cotton-Based Farming Systems – Results from a Field Trial in India

PubMed Central

Forster, Dionys; Andres, Christian; Verma, Rajeev; Zundel, Christine; Messmer, Monika M.; Mäder, Paul

2013-01-01

The debate on the relative benefits of conventional and organic farming systems has in recent time gained significant interest. So far, global agricultural development has focused on increased productivity rather than on a holistic natural resource management for food security. Thus, developing more sustainable farming practices on a large scale is of utmost importance. However, information concerning the performance of farming systems under organic and conventional management in tropical and subtropical regions is scarce. This study presents agronomic and economic data from the conversion phase (2007–2010) of a farming systems comparison trial on a Vertisol soil in Madhya Pradesh, central India. A cotton-soybean-wheat crop rotation under biodynamic, organic and conventional (with and without Bt cotton) management was investigated. We observed a significant yield gap between organic and conventional farming systems in the 1st crop cycle (cycle 1: 2007–2008) for cotton (−29%) and wheat (−27%), whereas in the 2nd crop cycle (cycle 2: 2009–2010) cotton and wheat yields were similar in all farming systems due to lower yields in the conventional systems. In contrast, organic soybean (a nitrogen fixing leguminous plant) yields were marginally lower than conventional yields (−1% in cycle 1, −11% in cycle 2). Averaged across all crops, conventional farming systems achieved significantly higher gross margins in cycle 1 (+29%), whereas in cycle 2 gross margins in organic farming systems were significantly higher (+25%) due to lower variable production costs but similar yields. Soybean gross margin was significantly higher in the organic system (+11%) across the four harvest years compared to the conventional systems. Our results suggest that organic soybean production is a viable option for smallholder farmers under the prevailing semi-arid conditions in India. Future research needs to elucidate the long-term productivity and profitability, particularly of
Steroid biotransformations in biphasic systems with Yarrowia lipolytica expressing human liver cytochrome P450 genes

PubMed Central

2012-01-01

Background Yarrowia lipolytica efficiently metabolizes and assimilates hydrophobic compounds such as n-alkanes and fatty acids. Efficient substrate uptake is enabled by naturally secreted emulsifiers and a modified cell surface hydrophobicity and protrusions formed by this yeast. We were examining the potential of recombinant Y. lipolytica as a biocatalyst for the oxidation of hardly soluble hydrophobic steroids. Furthermore, two-liquid biphasic culture systems were evaluated to increase substrate availability. While cells, together with water soluble nutrients, are maintained in the aqueous phase, substrates and most of the products are contained in a second water-immiscible organic solvent phase. Results For the first time we have co-expressed the human cytochromes P450 2D6 and 3A4 genes in Y. lipolytica together with human cytochrome P450 reductase (hCPR) or Y. lipolytica cytochrome P450 reductase (YlCPR). These whole-cell biocatalysts were used for the conversion of poorly soluble steroids in biphasic systems. Employing a biphasic system with the organic solvent and Y. lipolytica carbon source ethyl oleate for the whole-cell bioconversion of progesterone, the initial specific hydroxylation rate in a 1.5 L stirred tank bioreactor was further increased 2-fold. Furthermore, the product formation was significantly prolonged as compared to the aqueous system. Co-expression of the human CPR gene led to a 4-10-fold higher specific activity, compared to the co-overexpression of the native Y. lipolytica CPR gene. Multicopy transformants showed a 50-70-fold increase of activity as compared to single copy strains. Conclusions Alkane-assimilating yeast Y. lipolytica, coupled with the described expression strategies, demonstrated its high potential for biotransformations of hydrophobic substrates in two-liquid biphasic systems. Especially organic solvents which can be efficiently taken up and/or metabolized by the cell might enable more efficient bioconversion as compared
Effects of prebiotics on immune system and cytokine expression.

PubMed

Shokryazdan, Parisa; Faseleh Jahromi, Mohammad; Navidshad, Bahman; Liang, Juan Boo

2017-02-01

Nowadays, use of prebiotics as feed and food additives has received increasing interest because of the beneficial effects of prebiotics on the health of animals and humans. One of the beneficial effects of prebiotics is stimulation of immune system, which can be direct or indirect through increasing population of beneficial microbes or probiotics, especially lactic acid bacteria and bifidobacteria, in the gut. An important mechanism of action of probiotics and prebiotics, by which they can affect the immune system, is changing the expression of cytokines. The present review tried to summarize the findings of studies that investigated the effects of prebiotics on immune system with focusing on their effects on cytokine expression. Generally, most of reviewed studies indicated beneficial effects for prebiotics in terms of improving immune system, by increasing the expression of anti-inflammatory cytokines, while reducing the expressions of proinflammatory cytokines. However, most of studies mainly considered the indirect effects of prebiotics on the immune system (through changing the composition and population of gut microbiota), and their direct effects still need to be further studied using prebiotics with different degree of polymerization in different hosts.
Expression of the human blood coagulation protein factor XIIIa in Saccharomyces cerevisiae: dependence of the expression levels from host-vector systems and medium conditions.

PubMed

Bröker, M; Bäuml, O; Göttig, A; Ochs, J; Bodenbenner, M; Amann, E

1991-03-01

The human blood coagulation protein Factor XIIIa (FXIIIa) was expressed in Saccharomyces cerevisiae employing Escherichia coli-yeast shuttle vectors based on a 2-mu plasmid. Several factors affecting high production yield of recombinant FXIIIa were analysed. The use of the regulatable GAL-CYC1 hybrid promoter resulted in higher FXIIIa expression when compared with the constitutive ADCI promoter. Screening for suitable yeast strains for expression of FXIIIa under the transcriptional control of the GAL-CYC1 hybrid promoter revealed a broad spectrum of productivity. No obvious correlation between the expression rate and the genetic markers of the strains could be identified. The medium composition markedly influenced the FXIIIa expression rates. The expression of FXIIIa was strictly regulated by the carbon source. Glucose as the only sugar and energy source repressed the synthesis of FXIIIa, whereas addition of galactose induced FXIIIa expression. Special feeding schemes resulted in a productivity of up to 100 mg FXIIIa/l in shake flasks.
Engineering low-temperature expression systems for heterologous production of cold-adapted enzymes.

PubMed

Bjerga, Gro Elin Kjæreng; Lale, Rahmi; Williamson, Adele Kim

2016-01-01

Production of psychrophilic enzymes in the commonly used mesophilic expression systems is hampered by low intrinsic stability of the recombinant enzymes at the optimal host growth temperatures. Unless strategies for low-temperature expression are advanced, research on psychrophilic enzymes may end up being biased toward those that can be stably produced in commonly used mesophilic host systems. Two main strategies are currently being explored for the development of low-temperature expression in bacterial hosts: (i) low-temperature adaption of existing mesophilic expression systems, and (ii) development of new psychrophilic hosts. These developments include genetic engineering of the expression cassettes to optimize the promoter/operator systems that regulate heterologous expression. In this addendum we present our efforts in the development of such low-temperature expression systems, and speculate about future advancements in the field and potential applications.
A toy model for the yield of a tamped fission bomb

NASA Astrophysics Data System (ADS)

Reed, B. Cameron

2018-02-01

A simple expression is developed for estimating the yield of a tamped fission bomb, that is, a basic nuclear weapon comprising a fissile core jacketed by a surrounding neutron-reflecting tamper. This expression is based on modeling the nuclear chain reaction as a geometric progression in combination with a previously published expression for the threshold-criticality condition for such a core. The derivation is especially straightforward, as it requires no knowledge of diffusion theory and should be accessible to students of both physics and policy. The calculation can be set up as a single page spreadsheet. Application to the Little Boy and Fat Man bombs of World War II gives results in reasonable accord with published yield estimates for these weapons.
Maize ARGOS1 (ZAR1) transgenic alleles increase hybrid maize yield.

PubMed

Guo, Mei; Rupe, Mary A; Wei, Jun; Winkler, Chris; Goncalves-Butruille, Marymar; Weers, Ben P; Cerwick, Sharon F; Dieter, Jo Ann; Duncan, Keith E; Howard, Richard J; Hou, Zhenglin; Löffler, Carlos M; Cooper, Mark; Simmons, Carl R

2014-01-01

Crop improvement for yield and drought tolerance is challenging due to the complex genetic nature of these traits and environmental dependencies. This study reports that transgenic over-expression of Zea mays AR GOS1 (ZAR1) enhanced maize organ growth, grain yield, and drought-stress tolerance. The ZAR1 transgene exhibited environmental interactions, with yield increase under Temperate Dry and yield reduction under Temperate Humid or High Latitude environments. Native ZAR1 allele variation associated with drought-stress tolerance. Two founder alleles identified in the mid-maturity germplasm of North America now predominate in Pioneer's modern breeding programme, and have distinct proteins, promoters and expression patterns. These two major alleles show heterotic group partitioning, with one predominant in Pioneer's female and the other in the male heterotic groups, respectively. These two alleles also associate with favourable crop performance when heterozygous. Allele-specific transgene testing showed that, of the two alleles discussed here, each allele differed in their impact on yield and environmental interactions. Moreover, when transgenically stacked together the allelic pair showed yield and environmental performance advantages over either single allele, resembling heterosis effects. This work demonstrates differences in transgenic efficacy of native alleles and the differences reflect their association with hybrid breeding performance.
Maize ARGOS1 (ZAR1) transgenic alleles increase hybrid maize yield

PubMed Central

Guo, Mei

2014-01-01

Crop improvement for yield and drought tolerance is challenging due to the complex genetic nature of these traits and environmental dependencies. This study reports that transgenic over-expression of Zea mays ARGOS1 (ZAR1) enhanced maize organ growth, grain yield, and drought-stress tolerance. The ZAR1 transgene exhibited environmental interactions, with yield increase under Temperate Dry and yield reduction under Temperate Humid or High Latitude environments. Native ZAR1 allele variation associated with drought-stress tolerance. Two founder alleles identified in the mid-maturity germplasm of North America now predominate in Pioneer’s modern breeding programme, and have distinct proteins, promoters and expression patterns. These two major alleles show heterotic group partitioning, with one predominant in Pioneer’s female and the other in the male heterotic groups, respectively. These two alleles also associate with favourable crop performance when heterozygous. Allele-specific transgene testing showed that, of the two alleles discussed here, each allele differed in their impact on yield and environmental interactions. Moreover, when transgenically stacked together the allelic pair showed yield and environmental performance advantages over either single allele, resembling heterosis effects. This work demonstrates differences in transgenic efficacy of native alleles and the differences reflect their association with hybrid breeding performance. PMID:24218327
Effect of chemical and mechanical weed control on cassava yield, soil quality and erosion under cassava cropping system

NASA Astrophysics Data System (ADS)

Islami, Titiek; Wisnubroto, Erwin; Utomo, Wani

2016-04-01

Three years field experiments were conducted to study the effect of chemical and mechanical weed control on soil quality and erosion under cassava cropping system. The experiment were conducted at University Brawijaya field experimental station, Jatikerto, Malang, Indonesia. The experiments were carried out from 2011 - 2014. The treatments consist of three cropping system (cassava mono culture; cassava + maize intercropping and cassava + peanut intercropping), and two weed control method (chemical and mechanical methods). The experimental result showed that the yield of cassava first year and second year did not influenced by weed control method and cropping system. However, the third year yield of cassava was influence by weed control method and cropping system. The cassava yield planted in cassava + maize intercropping system with chemical weed control methods was only 24 t/ha, which lower compared to other treatments, even with that of the same cropping system used mechanical weed control. The highest cassava yield in third year was obtained by cassava + peanuts cropping system with mechanical weed control method. After three years experiment, the soil of cassava monoculture system with chemical weed control method possessed the lowest soil organic matter, and soil aggregate stability. During three years of cropping soil erosion in chemical weed control method, especially on cassava monoculture, was higher compared to mechanical weed control method. The soil loss from chemical control method were 40 t/ha, 44 t/ha and 54 t/ha for the first, second and third year crop. The soil loss from mechanical weed control method for the same years was: 36 t/ha, 36 t/ha and 38 t/ha. Key words: herbicide, intercropping, soil organic matter, aggregate stability.
Estimating daily fat yield from a single milking on test day for herds with a robotic milking system.

PubMed

Peeters, R; Galesloot, P J B

2002-03-01

The objective of this study was to estimate the daily fat yield and fat percentage from one sampled milking per cow per test day in an automatic milking system herd, when the milking times and milk yields of all individual milkings are recorded by the automatic milking system. Multiple regression models were used to estimate the 24-h fat percentage when only one milking is sampled for components and milk yields and milking times are known for all milkings in the 24-h period before the sampled milking. In total, 10,697 cow test day records, from 595 herd tests at 91 Dutch herds milked with an automatic milking system, were used. The best model to predict 24-h fat percentage included fat percentage, protein percentage, milk yield and milking interval of the sampled milking, milk yield, and milking interval of the preceding milking, and the interaction between milking interval and the ratio of fat and protein percentage of the sampled milking. This model gave a standard deviation of the prediction error (SE) for 24-h fat percentage of 0.321 and a correlation between the predicted and actual 24-h fat percentage of 0.910. For the 24-h fat yield, we found SE = 90 g and correlation = 0.967. This precision is slightly better than that of present a.m.-p.m. testing schemes. Extra attention must be paid to correctly matching the sample jars and the milkings. Furthermore, milkings with an interval of less than 4 h must be excluded from sampling as well as milkings that are interrupted or that follow an interrupted milking. Under these restrictions (correct matching, interval of at least 4 h, and no interrupted milking), one sampled milking suffices to get a satisfactory estimate for the test-day fat yield.
A cohort study of a general surgery electronic consultation system: safety implications and impact on surgical yield.

PubMed

Ulloa, Jesus G; Russell, Marika D; Chen, Alice Hm; Tuot, Delphine S

2017-06-23

Electronic consultation (eConsult) systems have enhanced access to specialty expertise and enhanced care coordination among primary care and specialty care providers, while maintaining high primary care provider (PCP), specialist and patient satisfaction. Little is known about their impact on the efficiency of specialty care delivery, in particular surgical yield (percent of ambulatory visits resulting in a scheduled surgical case). Retrospective cohort of a random selection of 150 electronic consults from PCPs to a safety-net general surgery clinic for the three most common general surgery procedures (herniorrhaphy, cholecystectomy, anorectal procedures) in 2014. Electronic consultation requests were reviewed for the presence/absence of consult domains: symptom acuity/severity, diagnostic evaluation, concurrent medical conditions, and attempted diagnosis. Logic regression was used to examine the association between completeness of consult requests and scheduling an ambulatory clinic visit. Surgical yield was also calculated, as was the percentage of patients requiring unanticipated healthcare visits. In 2014, 1743 electronic consultations were submitted to general surgery. Among the 150 abstracted, the presence of consult domains ranged from 49% to 99%. Consult completeness was not associated with greater likelihood of scheduling an ambulatory visit. Seventy-six percent of consult requests (114/150) were scheduled for a clinic appointment and surgical yield was 46%; without an eConsult system, surgical yield would have been 35% (p=0.07). Among patients not scheduled for a clinic visit (n=36), 4 had related unanticipated emergency department visits. Econsult systems can be used to safely optimize the surgical yield of a safety-net general surgery service.
Enhancing digestibility and ethanol yield of Populus wood via expression of an engineered monolignol 4-O-methyltransferase

PubMed Central

Cai, Yuanheng; Zhang, Kewei; Kim, Hoon; Hou, Guichuan; Zhang, Xuebin; Yang, Huijun; Feng, Huan; Miller, Lisa; Ralph, John; Liu, Chang-Jun

2016-01-01

Producing cellulosic biofuels and bio-based chemicals from woody biomass is impeded by the presence of lignin polymer in the plant cell wall. Manipulating the monolignol biosynthetic pathway offers a promising approach to improved processability, but often impairs plant growth and development. Here, we show that expressing an engineered 4-O-methyltransferase that chemically modifies the phenolic moiety of lignin monomeric precursors, thus preventing their incorporation into the lignin polymer, substantially alters hybrid aspens' lignin content and structure. Woody biomass derived from the transgenic aspens shows a 62% increase in the release of simple sugars and up to a 49% increase in the yield of ethanol when the woody biomass is subjected to enzymatic digestion and yeast-mediated fermentation. Moreover, the cell wall structural changes do not affect growth and biomass production of the trees. Our study provides a useful strategy for tailoring woody biomass for bio-based applications. PMID:27349324

Direct multiplexed measurement of gene expression with color-coded probe pairs.

PubMed

Geiss, Gary K; Bumgarner, Roger E; Birditt, Brian; Dahl, Timothy; Dowidar, Naeem; Dunaway, Dwayne L; Fell, H Perry; Ferree, Sean; George, Renee D; Grogan, Tammy; James, Jeffrey J; Maysuria, Malini; Mitton, Jeffrey D; Oliveri, Paola; Osborn, Jennifer L; Peng, Tao; Ratcliffe, Amber L; Webster, Philippa J; Davidson, Eric H; Hood, Leroy; Dimitrov, Krassen

2008-03-01

We describe a technology, the NanoString nCounter gene expression system, which captures and counts individual mRNA transcripts. Advantages over existing platforms include direct measurement of mRNA expression levels without enzymatic reactions or bias, sensitivity coupled with high multiplex capability, and digital readout. Experiments performed on 509 human genes yielded a replicate correlation coefficient of 0.999, a detection limit between 0.1 fM and 0.5 fM, and a linear dynamic range of over 500-fold. Comparison of the NanoString nCounter gene expression system with microarrays and TaqMan PCR demonstrated that the nCounter system is more sensitive than microarrays and similar in sensitivity to real-time PCR. Finally, a comparison of transcript levels for 21 genes across seven samples measured by the nCounter system and SYBR Green real-time PCR demonstrated similar patterns of gene expression at all transcript levels.
Expression of recombinant antibacterial lactoferricin-related peptides from Pichia pastoris expression system.

PubMed

Chen, Gen-Hung; Chen, Wei-Ming; Huang, Guo-Ting; Chen, Yu-Wen; Jiang, Shann-Tzong

2009-10-28

Four recombinant antimicrobial peptide (rAMP) cDNAs, constructed from two goat lactoferricin-related peptide cDNAs (GLFcin and GLFcin II) with/without (His)(6)-Tag, were cloned into pPICZalphaC and transformed into Pichia pastoris SMD1168H. After methanol induction, these rAMPs were expressed and secreted into broth. They were purified after CM-Sepharose (without His-tg), HisTrap (with His-tg) and Sephadex G-25 chromatographies. The yield of purified rAMP was 0.15 mg/mL of broth. These 4 rAMPs were thermal-stable and with high antibacterial activity against Escherichia coli BCRC 11549, Pseudomonas aeruginosa BCRC 12450, Bacillus cereus BCRC 10603, Staphylococcus aureus BCRC 25923, Propioni bacterium acnes BCRC 10723, and Listera monocytogenes BCRC 14845. The minimum inhibitory concentration (MIC) of rAMPs against these indicators ranged from 4.07 to 16.00 mg/mL.
Genotype x environment interactions in milk yield and quality in Angus, Brahman, and reciprocal-cross cows on different forage systems.

PubMed

Brown, M A; Brown, A H; Jackson, W G; Miesner, J R

2001-07-01

Milk yield and quality were observed on 93 Angus, Brahman, and reciprocal-cross cows over 3 yr to evaluate the interactions of direct and maternal breed effects and heterosis with forage environment. Forage environments were common bermudagrass (BG), endophyte-infected tall fescue (E+), and a rotational system (ROT) of both forages, in which each forage (BG or E+) was grazed during its appropriate season, usually June through October for BG and November through May for E+. Milk yield was estimated each of 6 mo (April through September) via milking machine and converted to a 24-h basis. Milk fat, milk protein, and somatic cell count were analyzed by a commercial laboratory. Heterosis for milk yield was similar among forages, averaging 2.4 kg (P < 0.01). Expressed as percentages of purebred means, heterosis for milk yield was largest on E+ (52.8%), intermediate on ROT (39.3%), and smallest on BG (23.7%). Direct breed effects for milk yield favored Brahman, and they were similar among forages but tended to be larger for E+ (2.5 kg) and ROT (2.8 kg) than for BG (1.3 kg). Direct breed effects for milk fat favored Brahman and were similar among forages but tended to be larger for E+ (1.0%) and ROT (1.0%) than for BG (0.6%). Purebred cows exceeded crossbreds in milk protein by 0.1% on ROT (P < 0.10). Crossbred cows had lower somatic cell counts than purebreds on BG (P < 0.05), E+ (P < 0.01), or ROT (P > 0.30). Heterosis for somatic cell counts as percentages of purebred means was similar for BG (-68.3%) and E+ (-68.9%) and less favorable for ROT (-31.6%). Maternal breed effects for somatic cell count favored Angus on ROT (P < 0.10) with a similar nonsignificant trend on BG and E+. Direct breed effects for somatic cell count favored Brahman on ROT (P < 0.10) with similar nonsignificant trends on BG and E+. These results suggested that a rotation of cows from E+ to BG in the summer can partially alleviate negative effects of E+ on milk yield. Conclusions also indicated an
A new yield and failure theory for composite materials under static and dynamic loading

DOE PAGES

Daniel, Isaac M.; Daniel, Sam M.; Fenner, Joel S.

2017-09-12

In order to facilitate and accelerate the process of introducing, evaluating and adopting new material systems, it is important to develop/establish comprehensive and effective procedures of characterization, modeling and failure prediction of composite structures based on the properties of the constituent materials, e. g., fibers, matrix, and the single ply or lamina. A new yield/failure theory is proposed for predicting lamina yielding and failure under multi-axial states of stress including strain rate effects. It is based on the equivalent stress concept derived from energy principles and is expressed in terms of a single criterion. It is presented in the formmore » of master yield and failure envelopes incorporating strain rate effects. The theory can be further adapted and extended to the prediction of in situ first ply yielding and failure (FPY and FPF) and progressive damage of multi-directional laminates under static and dynamic loadings. The significance of this theory is that it allows for rapid screening of new composite materials without extensive testing and offers easily implemented design tools.« less
A new yield and failure theory for composite materials under static and dynamic loading

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

Daniel, Isaac M.; Daniel, Sam M.; Fenner, Joel S.

In order to facilitate and accelerate the process of introducing, evaluating and adopting new material systems, it is important to develop/establish comprehensive and effective procedures of characterization, modeling and failure prediction of composite structures based on the properties of the constituent materials, e. g., fibers, matrix, and the single ply or lamina. A new yield/failure theory is proposed for predicting lamina yielding and failure under multi-axial states of stress including strain rate effects. It is based on the equivalent stress concept derived from energy principles and is expressed in terms of a single criterion. It is presented in the formmore » of master yield and failure envelopes incorporating strain rate effects. The theory can be further adapted and extended to the prediction of in situ first ply yielding and failure (FPY and FPF) and progressive damage of multi-directional laminates under static and dynamic loadings. The significance of this theory is that it allows for rapid screening of new composite materials without extensive testing and offers easily implemented design tools.« less
A new maltose-inducible high-performance heterologous expression system in Bacillus subtilis.

PubMed

Yue, Jie; Fu, Gang; Zhang, Dawei; Wen, Jianping

2017-08-01

To improve heterologous proteins production, we constructed a maltose-inducible expression system in Bacillus subtilis. An expression system based on the promoter for maltose utilization constructed in B. subtilis. Successively, to improve the performance of the P malA -derived system, mutagenesis was employed by gradually shortening the length of P malA promoter and altering the spacing between the predicted MalR binding site and the -35 region. Furthermore, deletion of the maltose utilization genes (malL and yvdK) improved the P malA promoter activity. Finally, using this efficient maltose-inducible expression system, we enhanced the production of luciferase and D-aminoacylase, compared with the P hpaII system. A maltose-inducible expression system was constructed and evaluated. It could be used for high level expression of heterologous proteins production.
ROI on yield data analysis systems through a business process management strategy

NASA Astrophysics Data System (ADS)

Rehani, Manu; Strader, Nathan; Hanson, Jeff

2005-05-01

The overriding motivation for yield engineering is profitability. This is achieved through application of yield management. The first application is to continually reduce waste in the form of yield loss. New products, new technologies and the dynamic state of the process and equipment keep introducing new ways to cause yield loss. In response, the yield management efforts have to continually come up with new solutions to minimize it. The second application of yield engineering is to aid in accurate product pricing. This is achieved through predicting future results of the yield engineering effort. The more accurate the yield prediction, the more accurate the wafer start volume, the more accurate the wafer pricing. Another aspect of yield prediction pertains to gauging the impact of a yield problem and predicting how long that will last. The ability to predict such impacts again feeds into wafer start calculations and wafer pricing. The question then is that if the stakes on yield management are so high why is it that most yield management efforts are run like science and engineering projects and less like manufacturing? In the eighties manufacturing put the theory of constraints1 into practice and put a premium on stability and predictability in manufacturing activities, why can't the same be done for yield management activities? This line of introspection led us to define and implement a business process to manage the yield engineering activities. We analyzed the best known methods (BKM) and deployed a workflow tool to make them the standard operating procedure (SOP) for yield managment. We present a case study in deploying a Business Process Management solution for Semiconductor Yield Engineering in a high-mix ASIC environment. We will present a description of the situation prior to deployment, a window into the development process and a valuation of the benefits.
Tunable Control of an Escherichia coli Expression System for the Overproduction of Membrane Proteins by Titrated Expression of a Mutant lac Repressor.

PubMed

Kim, Seong Keun; Lee, Dae-Hee; Kim, Oh Cheol; Kim, Jihyun F; Yoon, Sung Ho

2017-09-15

Most inducible expression systems suffer from growth defects, leaky basal induction, and inhomogeneous expression levels within a host cell population. These difficulties are most prominent with the overproduction of membrane proteins that are toxic to host cells. Here, we developed an Escherichia coli inducible expression system for membrane protein production based on titrated expression of a mutant lac repressor (mLacI). Performance of the mLacI inducible system was evaluated in conjunction with commonly used lac operator-based expression vectors using a T7 or tac promoter. Remarkably, expression of a target gene can be titrated by the dose-dependent addition of l-rhamnose, and the expression levels were homogeneous in the cell population. The developed system was successfully applied to overexpress three membrane proteins that were otherwise difficult to produce in E. coli. This gene expression control system can be easily applied to a broad range of existing protein expression systems and should be useful in constructing genetic circuits that require precise output signals.
The TCP4 transcription factor of Arabidopsis blocks cell division in yeast at G1 {yields} S transition

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

Aggarwal, Pooja; Padmanabhan, Bhavna; Bhat, Abhay

2011-07-01

Highlights: {yields} TCP4 is a class II TCP transcription factor, that represses cell division in Arabidopsis. {yields} TCP4 expression in yeast retards cell division by blocking G1 {yields} S transition. {yields} Genome-wide expression studies and Western analysis reveals stabilization of cell cycle inhibitor Sic1, as possible mechanism. -- Abstract: The TCP transcription factors control important aspects of plant development. Members of class I TCP proteins promote cell cycle by regulating genes directly involved in cell proliferation. In contrast, members of class II TCP proteins repress cell division. While it has been postulated that class II proteins induce differentiation signal, theirmore » exact role on cell cycle has not been studied. Here, we report that TCP4, a class II TCP protein from Arabidopsis that repress cell proliferation in developing leaves, inhibits cell division by blocking G1 {yields} S transition in budding yeast. Cells expressing TCP4 protein with increased transcriptional activity fail to progress beyond G1 phase. By analyzing global transcriptional status of these cells, we show that expression of a number of cell cycle genes is altered. The possible mechanism of G1 {yields} S arrest is discussed.« less
Holographic lens spectrum splitting photovoltaic system for increased diffuse collection and annual energy yield

NASA Astrophysics Data System (ADS)

Vorndran, Shelby D.; Wu, Yuechen; Ayala, Silvana; Kostuk, Raymond K.

2015-09-01

Concentrating and spectrum splitting photovoltaic (PV) modules have a limited acceptance angle and thus suffer from optical loss under off-axis illumination. This loss manifests itself as a substantial reduction in energy yield in locations where a significant portion of insulation is diffuse. In this work, a spectrum splitting PV system is designed to efficiently collect and convert light in a range of illumination conditions. The system uses a holographic lens to concentrate shortwavelength light onto a smaller, more expensive indium gallium phosphide (InGaP) PV cell. The high efficiency PV cell near the axis is surrounded with silicon (Si), a less expensive material that collects a broader portion of the solar spectrum. Under direct illumination, the device achieves increased conversion efficiency from spectrum splitting. Under diffuse illumination, the device collects light with efficiency comparable to a flat-panel Si module. Design of the holographic lens is discussed. Optical efficiency and power output of the module under a range of illumination conditions from direct to diffuse are simulated with non-sequential raytracing software. Using direct and diffuse Typical Metrological Year (TMY3) irradiance measurements, annual energy yield of the module is calculated for several installation sites. Energy yield of the spectrum splitting module is compared to that of a full flat-panel Si reference module.
Enhancing digestibility and ethanol yield of Populus wood via expression of an engineered monolignol 4-O-methyltransferase

DOE PAGES

Cai, Yuanheng; Zhang, Kewei; Kim, Hoon; ...

2016-06-28

Producing cellulosic biofuels and bio-based chemicals from woody biomass is impeded by the presence of lignin polymer in the plant cell wall. Manipulating the monolignol biosynthetic pathway offers a promising approach to improved processability, but often impairs plant growth and development. Here, we show that expressing an engineered 4-O-methyltransferase that chemically modifies the phenolic moiety of lignin monomeric precursors, thus preventing their incorporation into the lignin polymer, substantially alters hybrid aspens’ lignin content and structure. Woody biomass derived from the transgenic aspens shows a 62% increase in the release of simple sugars and up to a 49% increase in themore » yield of ethanol when the woody biomass is subjected to enzymatic digestion and yeast-mediated fermentation. Furthermore, the cell wall structural changes do not affect growth and biomass production of the trees. Our study provides a useful strategy for tailoring woody biomass for bio-based applications.« less
Arabidopsis Enhanced Drought Tolerance1/HOMEODOMAIN GLABROUS11 Confers Drought Tolerance in Transgenic Rice without Yield Penalty1[W][OA

PubMed Central

Yu, Linhui; Chen, Xi; Wang, Zhen; Wang, Shimei; Wang, Yuping; Zhu, Qisheng; Li, Shigui; Xiang, Chengbin

2013-01-01

Enhancing drought tolerance without yield decrease has been a great challenge in crop improvement. Here, we report the Arabidopsis (Arabidopsis thaliana) homodomain-leucine zipper transcription factor Enhanced Drought Tolerance/HOMEODOMAIN GLABROUS11 (EDT1/HDG11) was able to confer drought tolerance and increase grain yield in transgenic rice (Oryza sativa) plants. The improved drought tolerance was associated with a more extensive root system, reduced stomatal density, and higher water use efficiency. The transgenic rice plants also had higher levels of abscisic acid, proline, soluble sugar, and reactive oxygen species-scavenging enzyme activities during stress treatments. The increased grain yield of the transgenic rice was contributed by improved seed setting, larger panicle, and more tillers as well as increased photosynthetic capacity. Digital gene expression analysis indicated that AtEDT1/HDG11 had a significant influence on gene expression profile in rice, which was consistent with the observed phenotypes of transgenic rice plants. Our study shows that AtEDT1/HDG11 can improve both stress tolerance and grain yield in rice, demonstrating the efficacy of AtEDT1/HDG11 in crop improvement. PMID:23735506
Construction and development of an auto-regulatory gene expression system in Bacillus subtilis.

PubMed

Guan, Chengran; Cui, Wenjing; Cheng, Jintao; Zhou, Li; Guo, Junling; Hu, Xu; Xiao, Guoping; Zhou, Zhemin

2015-09-21

Bacillus subtilis is an all-important Gram-positive bacterium of valuable biotechnological utility that has been widely used to over-produce industrially and pharmaceutically relevant proteins. There are a variety of expression systems in terms of types of transcriptional patterns, among which the auto-inducible and growth-phase-dependent promoters are gaining increasing favor due to their inducer-independent feature, allowing for the potential to industrially scale-up. To expand the applicability of the auto-inducible expression system, a novel auto-regulatory expression system coupled with cell density was constructed and developed in B. subtilis using the quorum-sensing related promoter srfA (PsrfA). The promoter of the srf operon was used to construct an expression plasmid with the green fluorescent protein (GFP) downstream of PsrfA. The expression displayed a cell-density-dependent pattern in that GFP had a fairly low expression level at the early exponential stage and was highly expressed at the late exponential as well as the stationary stages. Moreover, the recombinant system had a similar expression pattern in wild-type B. subtilis 168, WB600, and WB800, as well as in B. subtilis 168 derivative strain 1681, with the complete deletion of PsrfA, indicating the excellent compatibility of this system. Noticeably, the expression strength of PsrfA was enhanced by optimizing the -10 and -35 core sequence by substituting both sequences with consensus sequences. Importantly, the expression pattern was successfully developed in an auto-regulatory cell-density coupling system by the simple addition of glucose in which GFP could not be strongly expressed until glucose was depleted, resulting in a greater amount of the GFP product and increased cell density. The expression system was eventually tested by the successful over-production of aminopeptidase to a desired level. The auto-regulatory cell density coupling system that is mediated by PsrfA is a novel expression
Transient Expression and Purification of Horseradish Peroxidase C in Nicotiana benthamiana.

PubMed

Huddy, Suzanne M; Hitzeroth, Inga I; Meyers, Ann E; Weber, Brandon; Rybicki, Edward P

2018-01-01

Horseradish peroxidase (HRP) is a commercially important reagent enzyme used in molecular biology and in the diagnostic product industry. It is typically purified from the roots of the horseradish ( Armoracia rusticana ); however, this crop is only available seasonally, yields are variable and often low, and the product is a mixture of isoenzymes. Engineering high-level expression in transiently transformed tobacco may offer a solution to these problems. In this study, a synthetic Nicotiana benthamiana codon-adapted full-length HRP isoenzyme gene as well as C-terminally truncated and both N- and C-terminally truncated versions of the HRP C gene were synthesized, and their expression in N. benthamiana was evaluated using an Agrobacterium tumefaciens -mediated transient expression system. The influence on HRP C expression levels of co-infiltration with a silencing suppressor (NSs) construct was also evaluated. Highest HRP C levels were consistently obtained using either the full length or C-terminally truncated HRP C constructs. HRP C purification by ion exchange chromatography gave an overall yield of 54% with a Reinheitszahl value of >3 and a specific activity of 458 U/mg. The high level of HRP C production in N. benthamiana in just five days offers an alternative, viable, and scalable system for production of this commercially significant enzyme.
Transient Expression and Purification of Horseradish Peroxidase C in Nicotiana benthamiana

PubMed Central

Huddy, Suzanne M.; Hitzeroth, Inga I.; Weber, Brandon; Rybicki, Edward P.

2018-01-01

Horseradish peroxidase (HRP) is a commercially important reagent enzyme used in molecular biology and in the diagnostic product industry. It is typically purified from the roots of the horseradish (Armoracia rusticana); however, this crop is only available seasonally, yields are variable and often low, and the product is a mixture of isoenzymes. Engineering high-level expression in transiently transformed tobacco may offer a solution to these problems. In this study, a synthetic Nicotiana benthamiana codon-adapted full-length HRP isoenzyme gene as well as C-terminally truncated and both N- and C-terminally truncated versions of the HRP C gene were synthesized, and their expression in N. benthamiana was evaluated using an Agrobacterium tumefaciens-mediated transient expression system. The influence on HRP C expression levels of co-infiltration with a silencing suppressor (NSs) construct was also evaluated. Highest HRP C levels were consistently obtained using either the full length or C-terminally truncated HRP C constructs. HRP C purification by ion exchange chromatography gave an overall yield of 54% with a Reinheitszahl value of >3 and a specific activity of 458 U/mg. The high level of HRP C production in N. benthamiana in just five days offers an alternative, viable, and scalable system for production of this commercially significant enzyme. PMID:29301255
A gene expression system offering multiple levels of regulation: the Dual Drug Control (DDC) system.

PubMed

Sudomoina, Marina; Latypova, Ekaterina; Favorova, Olga O; Golemis, Erica A; Serebriiskii, Ilya G

2004-04-29

Whether for cell culture studies of protein function, construction of mouse models to enable in vivo analysis of disease epidemiology, or ultimately gene therapy of human diseases, a critical enabling step is the ability to achieve finely controlled regulation of gene expression. Previous efforts to achieve this goal have explored inducible drug regulation of gene expression, and construction of synthetic promoters based on two-hybrid paradigms, among others. In this report, we describe the combination of dimerizer-regulated two-hybrid and tetracycline regulatory elements in an ordered cascade, placing expression of endpoint reporters under the control of two distinct drugs. In this Dual Drug Control (DDC) system, a first plasmid expresses fusion proteins to DBD and AD, which interact only in the presence of a small molecule dimerizer; a second plasmid encodes a cassette transcriptionally responsive to the first DBD, directing expression of the Tet-OFF protein; and a third plasmid encodes a reporter gene transcriptionally responsive to binding by Tet-OFF. We evaluate the dynamic range and specificity of this system in comparison to other available systems. This study demonstrates the feasibility of combining two discrete drug-regulated expression systems in a temporally sequential cascade, without loss of dynamic range of signal induction. The efficient layering of control levels allowed by this combination of elements provides the potential for the generation of complex control circuitry that may advance ability to regulate gene expression in vivo.
Simultaneous Breast Expression in Breastfeeding Women Is More Efficacious Than Sequential Breast Expression

PubMed Central

Garbin, Catherine P.; Hartmann, Peter E.; Kent, Jacqueline C.

2012-01-01

Abstract Introduction Simultaneous (SIM) breast expression saves mothers time compared with sequential (SEQ) expression, but it remains unclear whether the two methods differ in milk output efficiency and efficacy. Subjects and Methods The Showmilk device (Medela AG, Baar, Switzerland) was used to measure milk output and milk ejection during breast expression (electric pump) in 31 Australian breastfeeding mothers of term infants (median age, 19 weeks [interquartile range, 10–33 weeks]). The order of expression type (SIM/SEQ) and breast (left/right) was randomized. Results SIM expression yielded more milk ejections (p≤0.001) and greater amounts of milk at 2, 5, and 10 minutes (p≤0.01) and removed a greater total amount of milk (p≤0.01) and percentage of available milk (p<0.05) than SEQ expression. After SIM expression the cream content of both the overall (8.3% [p≤0.05]) and postexpression (12.6% [p≤0.001]) milk were greater. During SEQ expression, the breast expressed first had a shorter time to 50% and 80% of the total amount of milk than the breast expressed second (p≤0.05), but, overall, a similar percentage of available milk was removed from both breasts. Conclusions SIM expression stimulated more milk ejections and was a more efficient and efficacious method of expression, yielding milk with a higher energy content. PMID:23039397
Expression of proteins in Escherichia coli as fusions with maltose-binding protein to rescue non-expressed targets in a high-throughput protein-expression and purification pipeline

PubMed Central

Hewitt, Stephen N.; Choi, Ryan; Kelley, Angela; Crowther, Gregory J.; Napuli, Alberto J.; Van Voorhis, Wesley C.

2011-01-01

Despite recent advances, the expression of heterologous proteins in Escherichia coli for crystallization remains a nontrivial challenge. The present study investigates the efficacy of maltose-binding protein (MBP) fusion as a general strategy for rescuing the expression of target proteins. From a group of sequence-verified clones with undetectable levels of protein expression in an E. coli T7 expression system, 95 clones representing 16 phylogenetically diverse organisms were selected for recloning into a chimeric expression vector with an N-terminal histidine-tagged MBP. PCR-amplified inserts were annealed into an identical ligation-independent cloning region in an MBP-fusion vector and were analyzed for expression and solubility by high-throughput nickel-affinity binding. This approach yielded detectable expression of 72% of the clones; soluble expression was visible in 62%. However, the solubility of most proteins was marginal to poor upon cleavage of the MBP tag. This study offers large-scale evidence that MBP can improve the soluble expression of previously non-expressing proteins from a variety of eukaryotic and prokaryotic organisms. While the behavior of the cleaved proteins was disappointing, further refinements in MBP tagging may permit the more widespread use of MBP-fusion proteins in crystallographic studies. PMID:21904041
Factors Affecting Firm Yield and the Estimation of Firm Yield for Selected Streamflow-Dominated Drinking-Water-Supply Reservoirs in Massachusetts

USGS Publications Warehouse

Waldron, Marcus C.; Archfield, Stacey A.

2006-01-01

historical record is not valid. For multiple-reservoir systems, the firm-yield estimate was dependent on the reservoir system's configuration. The firm yield of a system is sensitive to how the water is transferred from one reservoir to another, the capacity of the connection between the reservoirs, and how seasonal variations in demand are represented in the FYE model. Firm yields for 25 (14 single-reservoir systems and 11 multiple-reservoir systems) reservoir systems were determined by using the historical records of streamflow and precipitation. Current water-use data indicate that, on average, 20 of the 25 reservoir systems in the study were operating below their estimated firm yield; during months with peak demands, withdrawals exceeded the firm yield for 8 reservoir systems.
A nonlinear dynamical system approach for the yielding behaviour of a viscoplastic material.

PubMed

Burghelea, Teodor; Moyers-Gonzalez, Miguel; Sainudiin, Raazesh

2017-03-08

A nonlinear dynamical system model that approximates a microscopic Gibbs field model for the yielding of a viscoplastic material subjected to varying external stresses recently reported in R. Sainudiin, M. Moyers-Gonzalez and T. Burghelea, Soft Matter, 2015, 11(27), 5531-5545 is presented. The predictions of the model are in fair agreement with microscopic simulations and are in very good agreement with the micro-structural semi-empirical model reported in A. M. V. Putz and T. I. Burghelea, Rheol. Acta, 2009, 48, 673-689. With only two internal parameters, the nonlinear dynamical system model captures several key features of the solid-fluid transition observed in experiments: the effect of the interactions between microscopic constituents on the yield point, the abruptness of solid-fluid transition and the emergence of a hysteresis of the micro-structural states upon increasing/decreasing external forces. The scaling behaviour of the magnitude of the hysteresis with the degree of the steadiness of the flow is consistent with previous experimental observations. Finally, the practical usefulness of the approach is demonstrated by fitting a rheological data set measured with an elasto-viscoplastic material.

High-yield maize with large net energy yield and small global warming intensity

PubMed Central

Grassini, Patricio; Cassman, Kenneth G.

2012-01-01

Addressing concerns about future food supply and climate change requires management practices that maximize productivity per unit of arable land while reducing negative environmental impact. On-farm data were evaluated to assess energy balance and greenhouse gas (GHG) emissions of irrigated maize in Nebraska that received large nitrogen (N) fertilizer (183 kg of N⋅ha−1) and irrigation water inputs (272 mm or 2,720 m3 ha−1). Although energy inputs (30 GJ⋅ha−1) were larger than those reported for US maize systems in previous studies, irrigated maize in central Nebraska achieved higher grain and net energy yields (13.2 Mg⋅ha−1 and 159 GJ⋅ha−1, respectively) and lower GHG-emission intensity (231 kg of CO2e⋅Mg−1 of grain). Greater input-use efficiencies, especially for N fertilizer, were responsible for better performance of these irrigated systems, compared with much lower-yielding, mostly rainfed maize systems in previous studies. Large variation in energy inputs and GHG emissions across irrigated fields in the present study resulted from differences in applied irrigation water amount and imbalances between applied N inputs and crop N demand, indicating potential to further improve environmental performance through better management of these inputs. Observed variation in N-use efficiency, at any level of applied N inputs, suggests that an N-balance approach may be more appropriate for estimating soil N2O emissions than the Intergovernmental Panel on Climate Change approach based on a fixed proportion of applied N. Negative correlation between GHG-emission intensity and net energy yield supports the proposition that achieving high yields, large positive energy balance, and low GHG emissions in intensive cropping systems are not conflicting goals. PMID:22232684
Maximized exoEarth candidate yields for starshades

NASA Astrophysics Data System (ADS)

Stark, Christopher C.; Shaklan, Stuart; Lisman, Doug; Cady, Eric; Savransky, Dmitry; Roberge, Aki; Mandell, Avi M.

2016-10-01

The design and scale of a future mission to directly image and characterize potentially Earth-like planets will be impacted, to some degree, by the expected yield of such planets. Recent efforts to increase the estimated yields, by creating observation plans optimized for the detection and characterization of Earth-twins, have focused solely on coronagraphic instruments; starshade-based missions could benefit from a similar analysis. Here we explore how to prioritize observations for a starshade given the limiting resources of both fuel and time, present analytic expressions to estimate fuel use, and provide efficient numerical techniques for maximizing the yield of starshades. We implemented these techniques to create an approximate design reference mission code for starshades and used this code to investigate how exoEarth candidate yield responds to changes in mission, instrument, and astrophysical parameters for missions with a single starshade. We find that a starshade mission operates most efficiently somewhere between the fuel- and exposuretime-limited regimes and, as a result, is less sensitive to photometric noise sources as well as parameters controlling the photon collection rate in comparison to a coronagraph. We produced optimistic yield curves for starshades, assuming our optimized observation plans are schedulable and future starshades are not thrust-limited. Given these yield curves, detecting and characterizing several dozen exoEarth candidates requires either multiple starshades or an η≳0.3.
Reduced product yield in chemical processes by second law effects

NASA Technical Reports Server (NTRS)

England, C.; Funk, J. E.

1980-01-01

An analysis of second law effects in chemical processes, where product yield is explicitly related to the individual irreversibilities within the process to indicate a maximum theoretical yield, is presented. Examples are given that indicate differences between first and second law approaches toward process efficiency and process yield. This analysis also expresses production capacity in terms of the heating value of a product. As a result, it is particularly convenient in analyzing fuel conversion plants and their potential for improvement. Relationships are also given for the effects of irreversibilities on requirements for process heat and for feedstocks.
Some correlations between sugar maple tree characteristics and sap and sugar yields

Treesearch

Barton M. Blum

1971-01-01

Simple correlation coefficients between various characteristics of sugar maple trees and sap sugar concentration, sap volume yield, and total sugar production are given for the 1968 sap season. Correlation coefficients in general indicated that individual tree characteristics that express tree and crown size are significantly related to sap volume yield and total sugar...
Challenges in breeding for yield increase for drought.

PubMed

Sinclair, Thomas R

2011-06-01

Crop genetic improvement for environmental stress at the molecular and physiological level is very complex and challenging. Unlike the example of the current major commercial transgenic crops for which biotic stress tolerance is based on chemicals alien to plants, the complex, redundant and homeostatic molecular and physiological systems existing in plants must be altered for drought tolerance improvement. Sophisticated tools must be developed to monitor phenotype expression at the crop level to characterize variation among genotypes across a range of environments. Once stress-tolerant cultivars are developed, regional probability distributions describing yield response across years will be necessary. This information can then aid in identifying environmental conditions for positive and negative responses to genetic modification to guide farmer selection of stress-tolerant cultivars. Copyright © 2011 Elsevier Ltd. All rights reserved.
Novel, high-yield red blood cell production methods from CD34-positive cells derived from human embryonic stem, yolk sac, fetal liver, cord blood, and peripheral blood.

PubMed

Olivier, Emmanuel; Qiu, Caihong; Bouhassira, Eric E

2012-08-01

The current supply of red blood cells expressing rare blood groups is not sufficient to cover all the existing transfusion needs for chronically transfused patients, such as sickle cell disease homozygous carriers, because of alloimmunization. In vitro production of cultured red blood cells is slowly emerging as a possible complement to the existing collection-based red blood cell procurement system. The yield of cultured red blood cells can theoretically be maximized by amplifying the stem, progenitor, or precursor compartment. Here, we combined methods designed to expand these three compartments to optimize the yield of cultured red blood cells and found that exposing CD34(+) cells to a short pulse of cytokines favorable for erythroid differentiation prior to stem cell expansion followed by progenitor expansion produced the highest yield of erythroid cells. This novel serum-free red blood cell production protocol was efficient on CD34(+) cells derived from human embryonic stem cells, 6-8-week yolk sacs, 16-18-week fetal livers, cord blood, and peripheral blood. The yields of cells obtained with these new protocols were larger by an order of magnitude than the yields observed previously. Globin expression analysis by high-performance liquid chromatography revealed that these expansion protocols generally yielded red blood cells that expressed a globin profile similar to that expected for the developmental age of the CD34(+) cells.
Transient, Inducible, Placenta-Specific Gene Expression in Mice

PubMed Central

Fan, Xiujun; Petitt, Matthew; Gamboa, Matthew; Huang, Mei; Dhal, Sabita; Druzin, Maurice L.; Wu, Joseph C.

2012-01-01

Molecular understanding of placental functions and pregnancy disorders is limited by the absence of methods for placenta-specific gene manipulation. Although persistent placenta-specific gene expression has been achieved by lentivirus-based gene delivery methods, developmentally and physiologically important placental genes have highly stage-specific functions, requiring controllable, transient expression systems for functional analysis. Here, we describe an inducible, placenta-specific gene expression system that enables high-level, transient transgene expression and monitoring of gene expression by live bioluminescence imaging in mouse placenta at different stages of pregnancy. We used the third generation tetracycline-responsive tranactivator protein Tet-On 3G, with 10- to 100-fold increased sensitivity to doxycycline (Dox) compared with previous versions, enabling unusually sensitive on-off control of gene expression in vivo. Transgenic mice expressing Tet-On 3G were created using a new integrase-based, site-specific approach, yielding high-level transgene expression driven by a ubiquitous promoter. Blastocysts from these mice were transduced with the Tet-On 3G-response element promoter-driving firefly luciferase using lentivirus-mediated placenta-specific gene delivery and transferred into wild-type pseudopregnant recipients for placenta-specific, Dox-inducible gene expression. Systemic Dox administration at various time points during pregnancy led to transient, placenta-specific firefly luciferase expression as early as d 5 of pregnancy in a Dox dose-dependent manner. This system enables, for the first time, reliable pregnancy stage-specific induction of gene expression in the placenta and live monitoring of gene expression during pregnancy. It will be widely applicable to studies of both placental development and pregnancy, and the site-specific Tet-On G3 mouse will be valuable for studies in a broad range of tissues. PMID:23011919
Development of a plasmid-based expression system in Clostridium thermocellum and its use to screen heterologous expression of bifunctional alcohol dehydrogenases (adhEs)

DOE PAGES

Hon, Shuen; Lanahan, Anthony; Tian, Liang; ...

2016-04-22

Clostridium thermocellum is a promising candidate for ethanol production from cellulosic biomass, but requires metabolic engineering to improve ethanol yield. A key gene in the ethanol production pathway is the bifunctional aldehyde and alcohol dehydrogenase, adhE. To explore the effects of overexpressing wild-type, mutant, and exogenous adhEs, we developed a new expression plasmid, pDGO144, that exhibited improved transformation efficiency and better gene expression than its predecessor, pDGO-66. This new expression plasmid will allow for many other metabolic engineering and basic research efforts in C. thermocellum. As proof of concept, we used this plasmid to express 12 different adhE genes (bothmore » wild type and mutant) from several organisms. Ethanol production varied between clones immediately after transformation, but tended to converge to a single value after several rounds of serial transfer. The previously described mutant C. thermocellum D494G adhE gave the best ethanol production, which is consistent with previously published results.« less
Development of a plasmid-based expression system in Clostridium thermocellum and its use to screen heterologous expression of bifunctional alcohol dehydrogenases (adhEs)

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

Hon, Shuen; Lanahan, Anthony; Tian, Liang

Clostridium thermocellum is a promising candidate for ethanol production from cellulosic biomass, but requires metabolic engineering to improve ethanol yield. A key gene in the ethanol production pathway is the bifunctional aldehyde and alcohol dehydrogenase, adhE. To explore the effects of overexpressing wild-type, mutant, and exogenous adhEs, we developed a new expression plasmid, pDGO144, that exhibited improved transformation efficiency and better gene expression than its predecessor, pDGO-66. This new expression plasmid will allow for many other metabolic engineering and basic research efforts in C. thermocellum. As proof of concept, we used this plasmid to express 12 different adhE genes (bothmore » wild type and mutant) from several organisms. Ethanol production varied between clones immediately after transformation, but tended to converge to a single value after several rounds of serial transfer. The previously described mutant C. thermocellum D494G adhE gave the best ethanol production, which is consistent with previously published results.« less
Development of a plasmid-based expression system in Clostridium thermocellum and its use to screen heterologous expression of bifunctional alcohol dehydrogenases (adhEs).

PubMed

Hon, Shuen; Lanahan, Anthony A; Tian, Liang; Giannone, Richard J; Hettich, Robert L; Olson, Daniel G; Lynd, Lee R

2016-12-01

Clostridium thermocellum is a promising candidate for ethanol production from cellulosic biomass, but requires metabolic engineering to improve ethanol yield. A key gene in the ethanol production pathway is the bifunctional aldehyde and alcohol dehydrogenase, adhE . To explore the effects of overexpressing wild-type, mutant, and exogenous adhE s, we developed a new expression plasmid, pDGO144, that exhibited improved transformation efficiency and better gene expression than its predecessor, pDGO-66. This new expression plasmid will allow for many other metabolic engineering and basic research efforts in C. thermocellum . As proof of concept, we used this plasmid to express 12 different adhE genes (both wild type and mutant) from several organisms. Ethanol production varied between clones immediately after transformation, but tended to converge to a single value after several rounds of serial transfer. The previously described mutant C. thermocellum D494G adhE gave the best ethanol production, which is consistent with previously published results.
Systemic spread of an RNA insect virus in plants expressing plant viral movement protein genes

PubMed Central

Dasgupta, Ranjit; Garcia, Bradley H.; Goodman, Robert M.

2001-01-01

Flock house virus (FHV), a single-stranded RNA insect virus, has previously been reported to cross the kingdom barrier and replicate in barley protoplasts and in inoculated leaves of several plant species [Selling, B. H., Allison, R. F. & Kaesberg, P. (1990) Proc. Natl. Acad. Sci. USA 87, 434–438]. There was no systemic movement of FHV in plants. We tested the ability of movement proteins (MPs) of plant viruses to provide movement functions and cause systemic spread of FHV in plants. We compared the growth of FHV in leaves of nontransgenic and transgenic plants expressing the MP of tobacco mosaic virus or red clover necrotic mosaic virus (RCNMV). Both MPs mobilized cell-to-cell and systemic movement of FHV in Nicotiana benthamiana plants. The yield of FHV was more than 100-fold higher in the inoculated leaves of transgenic plants than in the inoculated leaves of nontransgenic plants. In addition, FHV accumulated in the noninoculated upper leaves of both MP-transgenic plants. RCNMV MP was more efficient in mobilizing FHV to noninoculated upper leaves. We also report here that FHV replicates in inoculated leaves of six additional plant species: alfalfa, Arabidopsis, Brassica, cucumber, maize, and rice. Our results demonstrate that plant viral MPs cause cell-to-cell and long-distance movement of an animal virus in plants and offer approaches to the study of the evolution of viruses and mechanisms governing mRNA trafficking in plants as well as to the development of promising vectors for transient expression of foreign genes in plants. PMID:11296259
pOsNAR2.1:OsNAR2.1 expression enhances nitrogen uptake efficiency and grain yield in transgenic rice plants.

PubMed

Chen, Jingguang; Fan, Xiaoru; Qian, Kaiyun; Zhang, Yong; Song, Miaoquan; Liu, Yu; Xu, Guohua; Fan, Xiaorong

2017-10-01

The nitrate (NO3-) transporter has been selected as an important gene maker in the process of environmental adoption in rice cultivars. In this work, we transferred another native OsNAR2.1 promoter with driving OsNAR2.1 gene into rice plants. The transgenic lines with exogenous pOsNAR2.1:OsNAR2.1 constructs showed enhanced OsNAR2.1 expression level, compared with wild type (WT), and 15 N influx in roots increased 21%-32% in response to 0.2 mm and 2.5 mm 15NO3- and 1.25 mm 15 NH 4 15 NO 3 . Under these three N conditions, the biomass of the pOsNAR2.1:OsNAR2.1 transgenic lines increased 143%, 129% and 51%, and total N content increased 161%, 242% and 69%, respectively, compared to WT. Furthermore in field experiments we found the grain yield, agricultural nitrogen use efficiency (ANUE), and dry matter transfer of pOsNAR2.1:OsNAR2.1 plants increased by about 21%, 22% and 21%, compared to WT. We also compared the phenotypes of pOsNAR2.1:OsNAR2.1 and pOsNAR2.1:OsNRT2.1 transgenic lines in the field, found that postanthesis N uptake differed significantly between them, and in comparison with the WT. Postanthesis N uptake (PANU) increased approximately 39% and 85%, in the pOsNAR2.1:OsNAR2.1 and pOsNAR2.1:OsNRT2.1 transgenic lines, respectively, possibly because OsNRT2.1 expression was less in the pOsNAR2.1:OsNAR2.1 lines than in the pOsNAR2.1:OsNRT2.1 lines during the late growth stage. These results show that rice NO 3 - uptake, yield and NUE were improved by increased OsNAR2.1 expression via its native promoter. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.
Immunohistochemical Expression of Matrix Metalloproteinase-7 in Human Colorectal Adenomas Using Specified Automated Cellular Image Analysis System: A Clinicopathological Study

PubMed Central

Qasim, Ban J.; Ali, Hussam H.; Hussein, Alaa G.

2013-01-01

Background/Aim: To evaluate the immunohistochemical expression of matrix metalloproteinase-7 (MMP-7) in colorectal adenomas, and to correlate this expression with different clinicopathological parameters. Patients and Methods: The study was retrospectively designed. Thirty three paraffin blocks from patients with colorectal adenoma and 20 samples of non-tumerous colonic tissue taken as control group were included in the study. MMP-7 expression was assessed by immunohistochemistry method. The scoring of immunohistochemical staining was conducted utilizing a specified automated cellular image analysis system (Digimizer). Results: The frequency of positive immunohistochemical expression of MMP-7 was significantly higher in adenoma than control group (45.45% versus 10%) (P value < 0.001). Strong MMP-7 staining was mainly seen in adenoma cases (30.30%) in comparison with control (0%) the difference is significant (P < 0.001). The three digital parameters of MMP-7 immunohistochemical expression (Area (A), Number of objects (N), and intensity (I)) were significantly higher in adenoma than control. Mean (A and I) of MMP-7 showed a significant correlation with large sized adenoma (≥ 1cm) (P < 0.05), also a significant positive correlation of the three digital parameters (A, N, and I) of MMP-7 expression with villous configuration and severe dysplasia in colorectal adenoma had been identified (P < 0.05). Conclusion: MMP-7 plays an important role in the growth and malignant conversion of colorectal adenomas as it is more likely to be expressed in advanced colorectal adenomatous polyps with large size, severe dysplasia and villous histology. The use of automated cellular image analysis system (Digmizer) to quantify immunohistochemical staining yields more consistent assay results, converts semi-quantitative assay to a truly quantitative assay, and improves assay objectivity and reproducibility. PMID:23319034
Regularization strategies for hyperplane classifiers: application to cancer classification with gene expression data.

PubMed

Andries, Erik; Hagstrom, Thomas; Atlas, Susan R; Willman, Cheryl

2007-02-01

Linear discrimination, from the point of view of numerical linear algebra, can be treated as solving an ill-posed system of linear equations. In order to generate a solution that is robust in the presence of noise, these problems require regularization. Here, we examine the ill-posedness involved in the linear discrimination of cancer gene expression data with respect to outcome and tumor subclasses. We show that a filter factor representation, based upon Singular Value Decomposition, yields insight into the numerical ill-posedness of the hyperplane-based separation when applied to gene expression data. We also show that this representation yields useful diagnostic tools for guiding the selection of classifier parameters, thus leading to improved performance.
Double promoter expression systems for recombinant protein production by industrial microorganisms.

PubMed

Öztürk, Sibel; Ergün, Burcu Gündüz; Çalık, Pınar

2017-10-01

Using double promoter expression systems is a promising approach to increase heterologous protein production. In this review, current double promoter expression systems for the production of recombinant proteins (r-proteins) by industrially important bacteria, Bacillus subtilis and Escherichia coli; and yeasts, Saccharomyces cerevisiae and Pichia pastoris, are discussed by assessing their potentials and drawbacks. Double promoter expression systems need to be designed to maintain a higher specific product formation rate within the production domain. While bacterial double promoter systems have been constructed as chimeric tandem promoters, yeast dual promoter systems have been developed as separate expression cassettes. To increase production and productivity, the optimal transcriptional activity should be justified either by simultaneously satisfying the requirements of both promoters, or by consecutively stimulating the changeover from one to another in a biphasic process or via successive-iterations. Thus, considering the dynamics of a fermentation process, double promoters can be classified according to their operational mechanisms, as: i) consecutively operating double promoter systems, and ii) simultaneously operating double promoter systems. Among these metabolic design strategies, extending the expression period with two promoters activated under different conditions, or enhancing the transcriptional activity with two promoters activated under similar conditions within the production domain, can be applied independently from the host. Novel studies with new insights, which aim a rational systematic design and construction of dual promoter expression vectors with tailored transcriptional activity, will empower r-protein production with enhanced production and productivity. Finally, the current state-of-the-art review emphasizes the advantages of double promoter systems along with the necessity for discovering new promoters for the development of more
Sodium nitrite induces acute central nervous system toxicity in guinea pigs exposed to systemic cell-free hemoglobin

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

Buehler, Paul W.; Butt, Omer I.; D'Agnillo, Felice, E-mail: felice.dagnillo@fda.hhs.gov

Highlights: {yields} Toxicological implications associated with the use of NaNO{sub 2} therapy to treat systemic cell-free Hb exposure are not well-defined. {yields} Systemic Hb exposure followed by NaNO{sub 2} infusion induces acute CNS toxicities in guinea pigs. {yields} These CNS effects were not reproduced by the infusion of cell-free Hb or NaNO{sub 2} alone. {yields} NaNO{sub 2}-mediated oxidation of cell-free Hb may play a causative role in the observed CNS changes. -- Abstract: Systemic cell-free hemoglobin (Hb) released via hemolysis disrupts vascular homeostasis, in part, through the scavenging of nitric oxide (NO). Sodium nitrite (NaNO{sub 2}) therapy can attenuate themore » hypertensive effects of Hb. However, the chemical reactivity of NaNO{sub 2} with Hb may enhance heme- or iron-mediated toxicities. Here, we investigate the effect of NaNO{sub 2} on the central nervous system (CNS) in guinea pigs exposed to systemic cell-free Hb. Intravascular infusion of NaNO{sub 2}, at doses sufficient to alleviate Hb-mediated blood pressure changes, reduced the expression of occludin, but not zona occludens-1 (ZO-1) or claudin-5, in cerebral tight junctions 4 h after Hb infusion. This was accompanied by increased perivascular heme oxygenase-1 expression, neuronal iron deposition, increased astrocyte and microglial activation, and reduced expression of neuron-specific nuclear protein (NeuN). These CNS changes were not observed in animals treated with Hb or NaNO{sub 2} alone. Taken together, these findings suggest that the use of nitrite salts to treat systemic Hb exposure may promote acute CNS toxicity.« less
[Pichia pastoris as an expression system for recombinant protein production].

PubMed

Ciarkowska, Anna; Jakubowska, Anna

2013-01-01

Pichia pastoris has become increasingly popular as a host for recombinant protein production in recent years. P. pastoris is more cost effective and allows achieving higher expression levels than insect and mammalian cells. It also offers some significant advantages over E. coli expression systems, such as avoiding problems with proper protein folding. Also, P. pastoris as an eukaryotic organism can carry out posttranslational modifications of produced proteins. Additionally, P. pastoris can produce high levels of recombinant proteins in extracellular medium which simplifies protein purification. Having many advantages over other expression systems makes P. pastoris an organism of choice for industrial protein production.
Hepatic steatosis inhibits autophagic proteolysis via impairment of autophagosomal acidification and cathepsin expression

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

Inami, Yoshihiro; Yamashina, Shunhei, E-mail: syamashi@juntendo.ac.jp; Izumi, Kousuke

2011-09-09

Highlights: {yields} Acidification of autophagosome was blunted in steatotic hepatocytes. {yields} Hepatic steatosis did not disturb fusion of isolated autophagosome and lysosome. {yields} Proteinase activity of cathepsin B and L in autolysosomes was inhibited by steatosis. {yields} Hepatic expression of cathepsin B and L was suppressed by steatosis. -- Abstract: Autophagy, one of protein degradation system, contributes to maintain cellular homeostasis and cell defense. Recently, some evidences indicated that autophagy and lipid metabolism are interrelated. Here, we demonstrate that hepatic steatosis impairs autophagic proteolysis. Though accumulation of autophagosome is observed in hepatocytes from ob/ob mice, expression of p62 was augmentedmore » in liver from ob/ob mice more than control mice. Moreover, degradation of the long-lived protein leucine was significantly suppressed in hepatocytes isolated from ob/ob mice. More than 80% of autophagosomes were stained by LysoTracker Red (LTR) in hepatocytes from control mice; however, rate of LTR-stained autophagosomes in hepatocytes were suppressed in ob/ob mice. On the other hand, clearance of autolysosomes loaded with LTR was blunted in hepatocytes from ob/ob mice. Although fusion of isolated autophagosome and lysosome was not disturbed, proteinase activity of cathepsin B and L in autolysosomes and cathepsin B and L expression of liver were suppressed in ob/ob mice. These results indicate that lipid accumulation blunts autophagic proteolysis via impairment of autophagosomal acidification and cathepsin expression.« less
A meteorologically-driven yield reduction model for spring and winter wheat

NASA Technical Reports Server (NTRS)

Ravet, F. W.; Cremins, W. J.; Taylor, T. W.; Ashburn, P.; Smika, D.; Aaronson, A. (Principal Investigator)

1983-01-01

A yield reduction model for spring and winter wheat was developed for large-area crop condition assessment. Reductions are expressed in percentage from a base yield and are calculated on a daily basis. The algorithm contains two integral components: a two-layer soil water budget model and a crop calendar routine. Yield reductions associated with hot, dry winds (Sukhovey) and soil moisture stress are determined. Input variables include evapotranspiration, maximum temperature and precipitation; subsequently crop-stage, available water holding percentage and stress duration are evaluated. No specific base yield is required and may be selected by the user; however, it may be generally characterized as the maximum likely to be produced commercially at a location.
Using heterologous expression systems to characterize potassium and sodium transport activities.

PubMed

Rodríguez, Alonso; Benito, Begoña; Cagnac, Olivier

2012-01-01

The expression of plant transporters in simple well-characterized cell systems is an irreplaceable technique for gaining insights into the kinetic and energetic features of plant transporters. Among all the available expression systems, yeast cells offer the highest simplicity and have the capacity to mimic the in vivo properties of plant transporters. Here, we describe the use of yeast mutants to express K(+) and Na(+) plant transporters and discuss some experimental problems that can produce misleading results.

Diverse rotations and poultry litter improves soybean yield

USDA-ARS?s Scientific Manuscript database

Continuous cropping systems without rotations or cover crops are perceived as unsustainable for long-term yield and soil health. Continuous systems, defined as continually producing a crop on the same parcel of land for more than three years, is thought to reduce yields. Given that crop rotations a...
Development and characterization of a high yield transportable pulsed neutron source with efficient and compact pulsed power system

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

Verma, Rishi, E-mail: rishiv9@gmail.com, E-mail: rishiv@barc.gov.in; Mishra, Ekansh; Dhang, Prosenjit

2016-09-15

The results of characterization experiments carried out on a newly developed dense plasma focus device based intense pulsed neutron source with efficient and compact pulsed power system are reported. Its high current sealed pseudospark switch based low inductance capacitor bank with maximum stored energy of ∼10 kJ is segregated into four modules of ∼2.5 kJ each and it cumulatively delivers peak current in the range of 400 kA–600 kA (corresponding to charging voltage range of 14 kV–18 kV) in a quarter time period of ∼2 μs. The neutron yield performance of this device has been optimized by discretely varying deuteriummore » filling gas pressure in the range of 6 mbar–11 mbar at ∼17 kV/550 kA discharge. At ∼7 kJ/8.5 mbar operation, the average neutron yield has been measured to be in the order of ∼4 × 10{sup 9} neutrons/pulse which is the highest ever reported neutron yield from a plasma focus device with the same stored energy. The average forward to radial anisotropy in neutron yield is found to be ∼2. The entire system is contained on a moveable trolley having dimensions 1.5 m × 1 m × 0.7 m and its operation and control (up to the distance of 25 m) are facilitated through optically isolated handheld remote console. The overall compactness of this system provides minimum proximity to small as well as large samples for irradiation. The major intended application objective of this high neutron yield dense plasma focus device development is to explore the feasibility of active neutron interrogation experiments by utilization of intense pulsed neutron sources.« less
Development and characterization of a high yield transportable pulsed neutron source with efficient and compact pulsed power system.

PubMed

Verma, Rishi; Mishra, Ekansh; Dhang, Prosenjit; Sagar, Karuna; Meena, Manraj; Shyam, Anurag

2016-09-01

The results of characterization experiments carried out on a newly developed dense plasma focus device based intense pulsed neutron source with efficient and compact pulsed power system are reported. Its high current sealed pseudospark switch based low inductance capacitor bank with maximum stored energy of ∼10 kJ is segregated into four modules of ∼2.5 kJ each and it cumulatively delivers peak current in the range of 400 kA-600 kA (corresponding to charging voltage range of 14 kV-18 kV) in a quarter time period of ∼2 μs. The neutron yield performance of this device has been optimized by discretely varying deuterium filling gas pressure in the range of 6 mbar-11 mbar at ∼17 kV/550 kA discharge. At ∼7 kJ/8.5 mbar operation, the average neutron yield has been measured to be in the order of ∼4 × 10 9 neutrons/pulse which is the highest ever reported neutron yield from a plasma focus device with the same stored energy. The average forward to radial anisotropy in neutron yield is found to be ∼2. The entire system is contained on a moveable trolley having dimensions 1.5 m × 1 m × 0.7 m and its operation and control (up to the distance of 25 m) are facilitated through optically isolated handheld remote console. The overall compactness of this system provides minimum proximity to small as well as large samples for irradiation. The major intended application objective of this high neutron yield dense plasma focus device development is to explore the feasibility of active neutron interrogation experiments by utilization of intense pulsed neutron sources.
Regional crop yield forecasting: a probabilistic approach

NASA Astrophysics Data System (ADS)

de Wit, A.; van Diepen, K.; Boogaard, H.

2009-04-01

Information on the outlook on yield and production of crops over large regions is essential for government services dealing with import and export of food crops, for agencies with a role in food relief, for international organizations with a mandate in monitoring the world food production and trade, and for commodity traders. Process-based mechanistic crop models are an important tool for providing such information, because they can integrate the effect of crop management, weather and soil on crop growth. When properly integrated in a yield forecasting system, the aggregated model output can be used to predict crop yield and production at regional, national and continental scales. Nevertheless, given the scales at which these models operate, the results are subject to large uncertainties due to poorly known weather conditions and crop management. Current yield forecasting systems are generally deterministic in nature and provide no information about the uncertainty bounds on their output. To improve on this situation we present an ensemble-based approach where uncertainty bounds can be derived from the dispersion of results in the ensemble. The probabilistic information provided by this ensemble-based system can be used to quantify uncertainties (risk) on regional crop yield forecasts and can therefore be an important support to quantitative risk analysis in a decision making process.
Positive Bioluminescence Imaging of MicroRNA Expression in Small Animal Models Using an Engineered Genetic-Switch Expression System, RILES.

PubMed

Baril, Patrick; Pichon, Chantal

2016-01-01

MicroRNAs (miRNAs) are a class of small, noncoding RNAs which regulate gene expression by directing their target mRNA for degradation or translational repression. Since their discovery in the early 1990s, miRNAs have emerged as key components in the posttranscriptional regulation of gene networks, shaping many biological processes from development, morphogenesis, differentiation, proliferation and apoptosis. Although understanding of the molecular basis of miRNA biology is improving, methods to monitor the dynamic and the spatiotemporal aspects of miRNA expression under physiopathological conditions are required. However, monitoring of miRNAs is difficult due to their small size, low abundance, high degree of sequence similarity, and their dynamic expression pattern which is subjected to tight transcriptional and post-transcriptional controls. Recently, we developed a miRNA monitoring system called RILES, standing for RNAi-inducible expression system, which relies on an engineered regulatable expression system, to switch on the expression of the luciferase gene when the targeted miRNA is expressed in cells. We demonstrated that RILES is a specific, sensitive, and robust method to determine the fine-tuning of miRNA expression during the development of an experimental pathological process in mice. Because RILES offers the possibility for longitudinal studies on individual subjects, sharper insights into miRNA regulation can be generated, with applications in physiology, pathophysiology and development of RNAi-based therapies. This chapter describes methods and protocols to monitor the expression of myomiR-206, -1, and -133 in the tibialis anterior muscle of mice. These protocols can be used and adapted to monitor the expression of other miRNAs in other biological processes.
MicroRNAs expression in ox-LDL treated HUVECs: MiR-365 modulates apoptosis and Bcl-2 expression

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

Qin, Bing; Xiao, Bo; Liang, Desheng

Highlights: {yields} We evaluated the role of miRNAs in ox-LDL induced apoptosis in ECs. {yields} We found 4 up-regulated and 11 down-regulated miRNAs in apoptotic ECs. {yields} Target genes of the dysregulated miRNAs regulate ECs apoptosis and atherosclerosis. {yields} MiR-365 promotes ECs apoptosis via suppressing Bcl-2 expression. {yields} MiR-365 inhibitor alleviates ECs apoptosis induced by ox-LDL. -- Abstract: Endothelial cells (ECs) apoptosis induced by oxidized low-density lipoprotein (ox-LDL) is thought to play a critical role in atherosclerosis. MicroRNAs (miRNAs) are a class of noncoding RNAs that posttranscriptionally regulate the expression of genes involved in diverse cell functions, including differentiation, growth,more » proliferation, and apoptosis. However, whether miRNAs are associated with ox-LDL induced apoptosis and their effect on ECs is still unknown. Therefore, this study evaluated potential miRNAs and their involvement in ECs apoptosis in response to ox-LDL stimulation. Microarray and qRT-PCR analysis performed on human umbilical vein endothelial cells (HUVECs) exposed to ox-LDL identified 15 differentially expressed (4 up- and 11 down-regulated) miRNAs. Web-based query tools were utilized to predict the target genes of the differentially expressed miRNAs, and the potential target genes were classified into different function categories with the gene ontology (GO) term and KEGG pathway annotation. In particular, bioinformatics analysis suggested that anti-apoptotic protein B-cell CLL/lymphoma 2 (Bcl-2) is a target gene of miR-365, an apoptomir up-regulated by ox-LDL stimulation in HUVECs. We further showed that transfection of miR-365 inhibitor partly restored Bcl-2 expression at both mRNA and protein levels, leading to a reduction of ox-LDL-mediated apoptosis in HUVECs. Taken together, our findings indicate that miRNAs participate in ox-LDL-mediated apoptosis in HUVECs. MiR-365 potentiates ox-LDL-induced ECs apoptosis by regulating the
High-yield production of herbicidal thaxtomins and analogs in a nonpathogenic Streptomyces strain.

PubMed

Jiang, Guangde; Zhang, Yucheng; Powell, Magan M; Zhang, Peilan; Zuo, Ran; Zhang, Yi; Kallifidas, Dimitrios; Tieu, Albert M; Luesch, Hendrik; Loria, Rosemary; Ding, Yousong

2018-03-30

Thaxtomins are virulence factors of most plant pathogenic Streptomyces strains. Due to their potent herbicidal activity, attractive environmental compatibility and inherent biodegradability, thaxtomins are key active ingredients of bioherbicides approved by the United States Environmental Protection Agency. However, the low yield of thaxtomins in native Streptomyces producers limits their wide agricultural applications. Here, we describe the high-yield production of thaxtomins in a heterologous host. The thaxtomin gene cluster from S. scabiei 87.22 was cloned and expressed in S. albus J1074 after chromosomal integration. The production of thaxtomins and nitro-tryptophan analogs were observed using LC-MS analysis. When culturing the engineered S. albus J1074 in the minimal medium TMDc, the yield of the most abundant and herbicidal analog, thaxtomin A, was 10 times higher than S. scabiei 87.22, and optimization of the medium resulted in the highest yield of thaxtomin analogs at about 222 mg/L. Further engineering of the thaxtomin biosynthetic gene cluster through gene deletion led to the production of multiple biosynthetic intermediates important to the chemical synthesis of new analogs. Additionally, the versatility of the thaxtomin biosynthetic system in S. albus J1074 was capitalized to produce one unnatural fluorinated analog 5-F-thaxtomin A, whose structure was elucidated by a combination of MS and 1D and 2D NMR analyses. Natural and unnatural thaxtomins demonstrated potent herbicidal activity in radish seedling assays. These results indicated that S. albus J1074 has the potential to produce thaxtomins and thereof with high yield, fostering their agricultural applications. IMPORTANCE Thaxtomins are agriculturally valuable herbicidal natural products but the productivity of native producers is limiting. Heterologous expression of thaxtomin gene cluster in S. albus J1074 resulted in the highest yield of thaxtomins ever reported, representing a significant leap
The Importance of Juvenile Root Traits for Crop Yields

NASA Astrophysics Data System (ADS)

White, Philip; Adu, Michael; Broadley, Martin; Brown, Lawrie; Dupuy, Lionel; George, Timothy; Graham, Neil; Hammond, John; Hayden, Rory; Neugebauer, Konrad; Nightingale, Mark; Ramsay, Gavin; Thomas, Catherine; Thompson, Jacqueline; Wishart, Jane; Wright, Gladys

2014-05-01

Genetic variation in root system architecture (RSA) is an under-exploited breeding resource. This is partly a consequence of difficulties in the rapid and accurate assessment of subterranean root systems. However, although the characterisation of root systems of large plants in the field are both time-consuming and labour-intensive, high-throughput (HTP) screens of root systems of juvenile plants can be performed in the field, glasshouse or laboratory. It is hypothesised that improving the root systems of juvenile plants can accelerate access to water and essential mineral elements, leading to rapid crop establishment and, consequently, greater yields. This presentation will illustrate how aspects of the juvenile root systems of potato (Solanum tuberosum L.) and oilseed rape (OSR; Brassica napus L.) correlate with crop yields and examine the reasons for such correlations. It will first describe the significant positive relationships between early root system development, phosphorus acquisition, canopy establishment and eventual yield among potato genotypes. It will report the development of a glasshouse assay for root system architecture (RSA) of juvenile potato plants, the correlations between root system architectures measured in the glasshouse and field, and the relationships between aspects of the juvenile root system and crop yields under drought conditions. It will then describe the development of HTP systems for assaying RSA of OSR seedlings, the identification of genetic loci affecting RSA in OSR, the development of mathematical models describing resource acquisition by OSR, and the correlations between root traits recorded in the HTP systems and yields of OSR in the field.
Automated Purification of Recombinant Proteins: Combining High-throughput with High Yield

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

Lin, Chiann Tso; Moore, Priscilla A.; Auberry, Deanna L.

2006-05-01

Protein crystallography, mapping protein interactions and other approaches of current functional genomics require not only purifying large numbers of proteins but also obtaining sufficient yield and homogeneity for downstream high-throughput applications. There is a need for the development of robust automated high-throughput protein expression and purification processes to meet these requirements. We developed and compared two alternative workflows for automated purification of recombinant proteins based on expression of bacterial genes in Escherichia coli: First - a filtration separation protocol based on expression of 800 ml E. coli cultures followed by filtration purification using Ni2+-NTATM Agarose (Qiagen). Second - a smallermore » scale magnetic separation method based on expression in 25 ml cultures of E.coli followed by 96-well purification on MagneHisTM Ni2+ Agarose (Promega). Both workflows provided comparable average yields of proteins about 8 ug of purified protein per unit of OD at 600 nm of bacterial culture. We discuss advantages and limitations of the automated workflows that can provide proteins more than 90 % pure in the range of 100 ug – 45 mg per purification run as well as strategies for optimization of these protocols.« less
Brazilian Soybean Yields and Yield Gaps Vary with Farm Size

NASA Astrophysics Data System (ADS)

Jeffries, G. R.; Cohn, A.; Griffin, T. S.; Bragança, A.

2017-12-01

Understanding the farm size-specific characteristics of crop yields and yield gaps may help to improve yields by enabling better targeting of technical assistance and agricultural development programs. Linking remote sensing-based yield estimates with property boundaries provides a novel view of the relationship between farm size and yield structure (yield magnitude, gaps, and stability over time). A growing literature documents variations in yield gaps, but largely ignores the role of farm size as a factor shaping yield structure. Research on the inverse farm size-productivity relationship (IR) theory - that small farms are more productive than large ones all else equal - has documented that yield magnitude may vary by farm size, but has not considered other yield structure characteristics. We examined farm size - yield structure relationships for soybeans in Brazil for years 2001-2015. Using out-of-sample soybean yield predictions from a statistical model, we documented 1) gaps between the 95th percentile of attained yields and mean yields within counties and individual fields, and 2) yield stability defined as the standard deviation of time-detrended yields at given locations. We found a direct relationship between soy yields and farm size at the national level, while the strength and the sign of the relationship varied by region. Soybean yield gaps were found to be inversely related to farm size metrics, even when yields were only compared to farms of similar size. The relationship between farm size and yield stability was nonlinear, with mid-sized farms having the most stable yields. The work suggests that farm size is an important factor in understanding yield structure and that opportunities for improving soy yields in Brazil are greatest among smaller farms.
Yielding of a model glass former: An interpretation with an effective system of icosahedra

NASA Astrophysics Data System (ADS)

Pinney, Rhiannon; Liverpool, Tanniemola B.; Royall, C. Patrick

2018-03-01

We consider the yielding under simple shear of a binary Lennard-Jones glass former whose super-Arrhenius dynamics are correlated with the formation of icosahedral structures. We recast this glass former as an effective system of icosahedra [Pinney et al., J. Chem. Phys. 143, 244507 (2015), 10.1063/1.4938424]. Looking at the small-strain region of sheared simulations, we observe that shear rates affect the shear localization behavior particularly at temperatures below the glass transition as defined with a fit to the Vogel-Fulcher-Tamman equation. At higher temperature, shear localization starts immediately on shearing for all shear rates. At lower temperatures, faster shear rates can result in a delayed start in shear localization, which begins close to the yield stress. Building from a previous work which considered steady-state shear [Pinney et al., J. Chem. Phys. 143, 244507 (2015), 10.1063/1.4938424], we interpret the response to shear and the shear localization in terms of a local effective temperature with our system of icosahedra. We find that the effective temperatures of the regions undergoing shear localization increase significantly with increasing strain (before reaching a steady-state plateau).
Evaluation of novel inducible promoter/repressor systems for recombinant protein expression in Lactobacillus plantarum.

PubMed

Heiss, Silvia; Hörmann, Angelika; Tauer, Christopher; Sonnleitner, Margot; Egger, Esther; Grabherr, Reingard; Heinl, Stefan

2016-03-10

Engineering lactic acid bacteria (LAB) is of growing importance for food and feed industry as well as for in vivo vaccination or the production of recombinant proteins in food grade organisms. Often, expression of a transgene is only desired at a certain time point or period, e.g. to minimize the metabolic burden for the host cell or to control the expression time span. For this purpose, inducible expression systems are preferred, though cost and availability of the inducing agent must be feasible. We selected the plasmid free strain Lactobacillus plantarum 3NSH for testing and characterization of novel inducible promoters/repressor systems. Their feasibility in recombinant protein production was evaluated. Expression of the reporter protein mCherry was monitored with the BioLector(®) micro-fermentation system. Reporter gene mCherry expression was compared under the control of different promoter/repressor systems: PlacA (an endogenous promoter/repressor system derived from L. plantarum 3NSH), PxylA (a promoter/repressor system derived from Bacillus megaterium DSMZ 319) and PlacSynth (synthetic promoter and codon-optimized repressor gene based on the Escherichia coli lac operon). We observed that PlacA was inducible solely by lactose, but not by non-metabolizable allolactose analoga. PxylA was inducible by xylose, yet showed basal expression under non-induced conditions. Growth on galactose (as compared to exponential growth phase on glucose) reduced basal mCherry expression at non-induced conditions. PlacSynth was inducible with TMG (methyl β-D-thiogalactopyranoside) and IPTG (isopropyl β-D-1-thiogalactopyranoside), but also showed basal expression without inducer. The promoter PlacSynth was used for establishment of a dual plasmid expression system, based on T7 RNA polymerase driven expression in L. plantarum. Comparative Western blot supported BioLector(®) micro-fermentation measurements. Conclusively, overall expression levels were moderate (compared to a
A whole stand growth and yield system for young longleaf pine plantations in Southwest Georgia

Treesearch

John R. Brooks; Steven B. Jack

2006-01-01

A whole stand growth and yield system for planted longleaf pine (Pinus palustris Mill.) was developed from permanent plot data collected annually over an 8 year period. The dataset consists of 12 intensively-managed longleaf pine plantations that are located in Lee, Worth, Mitchell, and Baker counties in southwest Georgia. Stand survival, dominant...
Using fluorometry and ion-sensitive microelectrodes to study the functional expression of heterologously-expressed ion channels and transporters in Xenopus oocytes

PubMed Central

Musa-Aziz, Raif; Boron, Walter F.; Parker, Mark D.

2010-01-01

The Xenopus laevis oocyte is a model system for the electrophysiological study of exogenous ion transporters. Three main reasons make the oocyte suitable for this purpose: (a) it has a large cell size (~1 mm diameter), (b) it has an established capacity to produce—from microinjected mRNAs or cRNAs—exogenous ion transporters with close-to-physiological post-translational modifications and actions, and (c) its membranes contain endogenous ion-transport activities which are usually smaller in magnitude than the activities of exogenously-expressed ion transporters. The expression of ion-transporters as green-fluorescent-protein fusions allows the fluorometric assay of transporter yield in living oocytes. Monitoring of transporter-mediated movement of ions such as Cl−, H+ (and hence base equivalents like OH−1 and HCO3−), K+, and Na+ is achieved by positioning the tips of ion-sensitive microelectrodes inside the oocyte and/or at the surface of the oocyte plasma membrane. The use of ion-sensitive electrodes is critical for studying net ion-movements mediated by electroneutral transporters. The combined use of fluorometry and electrophysiology expedites transporter study by allowing measurement of transporter yield prior to electrophysiological study and correlation of relative transporter yield with transport rates. PMID:20051266
Expression of codon-optmized phosphoenolpyruvate carboxylase gene from Glaciecola sp. HTCC2999 in Escherichia coli and its application for C4 chemical production.

PubMed

Park, Soohyun; Pack, Seung Pil; Lee, Jinwon

2012-08-01

We examined the expression of the phosphoenolpyruvate carboxylase (PEPC) gene from marine bacteria in Escherichia coli using codon optimization. The codon-optimized PEPC gene was expressed in the E. coli K-12 strain W3110. SDS-PAGE analysis revealed that the codon-optimized PEPC gene was only expressed in E. coli, and measurement of enzyme activity indicated the highest PEPC activity in the E. coli SGJS112 strain that contained the codon-optimized PEPC gene. In fermentation assays, the E. coli SGJS112 produced the highest yield of oxaloacetate using glucose as the source and produced a 20-times increase in the yield of malate compared to the control. We concluded that the codon optimization enabled E. coli to express the PEPC gene derived from the Glaciecola sp. HTCC2999. Also, the expressed protein exhibited an enzymatic activity similar to that of E. coli PEPC and increased the yield of oxaloacetate and malate in an E. coli system.
Quantitative self-assembly prediction yields targeted nanomedicines

NASA Astrophysics Data System (ADS)

Shamay, Yosi; Shah, Janki; Işık, Mehtap; Mizrachi, Aviram; Leibold, Josef; Tschaharganeh, Darjus F.; Roxbury, Daniel; Budhathoki-Uprety, Januka; Nawaly, Karla; Sugarman, James L.; Baut, Emily; Neiman, Michelle R.; Dacek, Megan; Ganesh, Kripa S.; Johnson, Darren C.; Sridharan, Ramya; Chu, Karen L.; Rajasekhar, Vinagolu K.; Lowe, Scott W.; Chodera, John D.; Heller, Daniel A.

2018-02-01

Development of targeted nanoparticle drug carriers often requires complex synthetic schemes involving both supramolecular self-assembly and chemical modification. These processes are generally difficult to predict, execute, and control. We describe herein a targeted drug delivery system that is accurately and quantitatively predicted to self-assemble into nanoparticles based on the molecular structures of precursor molecules, which are the drugs themselves. The drugs assemble with the aid of sulfated indocyanines into particles with ultrahigh drug loadings of up to 90%. We devised quantitative structure-nanoparticle assembly prediction (QSNAP) models to identify and validate electrotopological molecular descriptors as highly predictive indicators of nano-assembly and nanoparticle size. The resulting nanoparticles selectively targeted kinase inhibitors to caveolin-1-expressing human colon cancer and autochthonous liver cancer models to yield striking therapeutic effects while avoiding pERK inhibition in healthy skin. This finding enables the computational design of nanomedicines based on quantitative models for drug payload selection.
Visual tree grading systems for estimating lumber yields in young and mature southern pine

Treesearch

Alexander Clark; Robert H. McAlister

1998-01-01

New visual tree grading systems for mature southern pine ? 35 years old and young pine ? 35 years old based on number and size of branches in the lower bole are described. A series of lumber grade yield studies was conducted to test the new grading rules. A total of 214 natural loblolly pine (Pinus taeda L.) and shortleaf pine (P. echinata Mill) trees 9 to 20 inches...
Orbital Express fluid transfer demonstration system

NASA Astrophysics Data System (ADS)

Rotenberger, Scott; SooHoo, David; Abraham, Gabriel

2008-04-01

Propellant resupply of orbiting spacecraft is no longer in the realm of high risk development. The recently concluded Orbital Express (OE) mission included a fluid transfer demonstration that operated the hardware and control logic in space, bringing the Technology Readiness Level to a solid TRL 7 (demonstration of a system prototype in an operational environment). Orbital Express (funded by the Defense Advanced Research Projects Agency, DARPA) was launched aboard an Atlas-V rocket on March 9th, 2007. The mission had the objective of demonstrating technologies needed for routine servicing of spacecraft, namely autonomous rendezvous and docking, propellant resupply, and orbital replacement unit transfer. The demonstration system used two spacecraft. A servicing vehicle (ASTRO) performed multiple dockings with the client (NextSat) spacecraft, and performed a variety of propellant transfers in addition to exchanges of a battery and computer. The fluid transfer and propulsion system onboard ASTRO, in addition to providing the six degree-of-freedom (6 DOF) thruster system for rendezvous and docking, demonstrated autonomous transfer of monopropellant hydrazine to or from the NextSat spacecraft 15 times while on orbit. The fluid transfer system aboard the NextSat vehicle was designed to simulate a variety of client systems, including both blowdown pressurization and pressure regulated propulsion systems. The fluid transfer demonstrations started with a low level of autonomy, where ground controllers were allowed to review the status of the demonstration at numerous points before authorizing the next steps to be performed. The final transfers were performed at a full autonomy level where the ground authorized the start of a transfer sequence and then monitored data as the transfer proceeded. The major steps of a fluid transfer included the following: mate of the coupling, leak check of the coupling, venting of the coupling, priming of the coupling, fluid transfer, gauging
Heterologous Production and Yield Improvement of Epothilones in Burkholderiales Strain DSM 7029.

PubMed

Bian, Xiaoying; Tang, Biao; Yu, Yucong; Tu, Qiang; Gross, Frank; Wang, Hailong; Li, Aiying; Fu, Jun; Shen, Yuemao; Li, Yue-Zhong; Stewart, A Francis; Zhao, Guoping; Ding, Xiaoming; Müller, Rolf; Zhang, Youming

2017-07-21

The cloning of microbial natural product biosynthetic gene clusters and their heterologous expression in a suitable host have proven to be a feasible approach to improve the yield of valuable natural products and to begin mining cryptic natural products in microorganisms. Myxobacteria are a prolific source of novel bioactive natural products with only limited choices of heterologous hosts that have been exploited. Here, we describe the use of Burkholderiales strain DSM 7029 as a potential heterologous host for the functional expression of myxobacterial secondary metabolites. Using a newly established electroporation procedure, the 56 kb epothilone biosynthetic gene cluster from the myxobacterium Sorangium cellulosum was introduced into the chromosome of strain DSM 7029 by transposition. Production of epothilones A, B, C, and D was detected despite their yields being low. Optimization of the medium, introduction of the exogenous methylmalonyl-CoA biosynthetic pathway, and overexpression of rare tRNA genes resulted in an approximately 75-fold increase in the total yields of epothilones to 307 μg L -1 . These results show that strain DSM 7029 has the potential to produce epothilones with reasonable titers and might be a broadly applicable host for the heterologous expression of other myxobacterial polyketide synthases and nonribosomal peptide synthetases, expediting the process of genome mining.
Hierarchical Recognition Scheme for Human Facial Expression Recognition Systems

PubMed Central

Siddiqi, Muhammad Hameed; Lee, Sungyoung; Lee, Young-Koo; Khan, Adil Mehmood; Truc, Phan Tran Ho

2013-01-01

Over the last decade, human facial expressions recognition (FER) has emerged as an important research area. Several factors make FER a challenging research problem. These include varying light conditions in training and test images; need for automatic and accurate face detection before feature extraction; and high similarity among different expressions that makes it difficult to distinguish these expressions with a high accuracy. This work implements a hierarchical linear discriminant analysis-based facial expressions recognition (HL-FER) system to tackle these problems. Unlike the previous systems, the HL-FER uses a pre-processing step to eliminate light effects, incorporates a new automatic face detection scheme, employs methods to extract both global and local features, and utilizes a HL-FER to overcome the problem of high similarity among different expressions. Unlike most of the previous works that were evaluated using a single dataset, the performance of the HL-FER is assessed using three publicly available datasets under three different experimental settings: n-fold cross validation based on subjects for each dataset separately; n-fold cross validation rule based on datasets; and, finally, a last set of experiments to assess the effectiveness of each module of the HL-FER separately. Weighted average recognition accuracy of 98.7% across three different datasets, using three classifiers, indicates the success of employing the HL-FER for human FER. PMID:24316568

Non-conventional expression systems for the production of vaccine proteins and immunotherapeutic molecules

PubMed Central

Legastelois, Isabelle; Buffin, Sophie; Peubez, Isabelle; Mignon, Charlotte; Sodoyer, Régis; Werle, Bettina

2017-01-01

ABSTRACT The increasing demand for recombinant vaccine antigens or immunotherapeutic molecules calls into question the universality of current protein expression systems. Vaccine production can require relatively low amounts of expressed materials, but represents an extremely diverse category consisting of different target antigens with marked structural differences. In contrast, monoclonal antibodies, by definition share key molecular characteristics and require a production system capable of very large outputs, which drives the quest for highly efficient and cost-effective systems. In discussing expression systems, the primary assumption is that a universal production platform for vaccines and immunotherapeutics will unlikely exist. This review provides an overview of the evolution of traditional expression systems, including mammalian cells, yeast and E.coli, but also alternative systems such as other bacteria than E. coli, transgenic animals, insect cells, plants and microalgae, Tetrahymena thermophila, Leishmania tarentolae, filamentous fungi, cell free systems, and the incorporation of non-natural amino acids. PMID:27905833
Development of an efficient E. coli expression and purification system for a catalytically active, human Cullin3-RINGBox1 protein complex and elucidation of its quaternary structure with Keap1

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

Small, Evan; Eggler, Aimee; Mesecar, Andrew D., E-mail: amesecar@purdue.edu

2010-10-01

Research highlights: {yields} A novel expression strategy was used to purify Cul3-Rbx1 from E. coli. {yields} The Cul3-Rbx1 complex is fully active and catalyzes ubiquitination of Nrf2 in vitro. {yields} Cul3, Rbx1, and Keap1 form a complex with unique stoichiometry of 1:1:2. -- Abstract: The Cullin3-based E3 ubiquitin ligase complex is thought to play an important role in the cellular response to oxidative stress and xenobiotic assault. While limited biochemical studies of the ligase's role in these complex signaling pathways are beginning to emerge, structural studies are lagging far behind due to the inability to acquire sufficient quantities of full-length,more » highly pure and active Cullin3. Here we describe the design and construction of an optimized expression and purification system for the full-length, human Cullin3-RINGBox 1 (Rbx1) protein complex from Escherichia coli. The dual-expression system is comprised of codon-optimized Cullin3 and Rbx1 genes co-expressed from a single pET-Duet-1 plasmid. Rapid purification of the Cullin3-Rbx1 complex is achieved in two steps via an affinity column followed by size-exclusion chromatography. Approximately 15 mg of highly pure and active Cullin3-Rbx1 protein from 1 L of E. coli culture can be achieved. Analysis of the quaternary structure of the Cullin3-Rbx1 and Cullin3-Rbx1-Keap1 complexes by size-exclusion chromatography and analytical ultracentrifugation indicates a 1:1 stoichiometry for the Cullin3-Rbx1 complex (MW = 111 kDa), and a 1:1:2 stoichiometry for the Cullin3-Rbx1-Keap1 complex (MW = 280 kDa). This latter complex has a novel quaternary structural organization for cullin E3 ligases, and it is fully active based on an in vitro Cullin3-Rbx1-Keap1-Nrf2 ubiquitination activity assay that was developed and optimized in this study.« less
Improved expression of recombinant plant-made hEGF.

PubMed

Thomas, David Rhys; Walmsley, Amanda Maree

2014-11-01

The yield of recombinant hEGF was increased approximately tenfold through a range of optimisations. Further, the recombinant protein was found to have biological activity comparable to commercial hEGF. Human epidermal growth factor (hEGF) is a powerful mitogen that can enhance the healing of a wide range of injuries, including burns, cuts, diabetic ulcers and gastric ulcers. However, despite its clinical value, hEGF is only consistently used for the treatment of chronic diabetic ulcers due to its high cost. In this study, hEGF was transiently expressed in Nicotiana benthamiana plants and targeted to the apoplast, ER and vacuole. Several other approaches were also included in a stepwise fashion to identify the optimal conditions for the expression of recombinant hEGF. Expression was found to be highest in the vacuole, while targeting hEGF to the ER caused a decrease in total soluble protein (TSP). Using a codon optimised sequence was found to increase vacuolar targeted hEGF yield by ~34 %, while it was unable to increase the yield of ER targeted hEGF. The use of the P19 silencing inhibitor was able to further increase expression by over threefold, and using 5-week-old plants significantly increased expression compared to 4- or 6-week-old-plants. The combined effect of these optimisations increased expression tenfold over the initial apoplast targeted construct to an average yield of 6.24 % of TSP. The plant-made hEGF was then shown to be equivalent to commercial E. coli derived hEGF in its ability to promote the proliferation of mouse keratinocytes. This study supports the potential for plants to be used for the commercial production of hEGF, and identifies a potential limitation for the further improvement of recombinant protein yields.
Molecular cloning, sequence characterization and recombinant expression of Nanog gene in goat fibroblast cells using lentiviral based expression system.

PubMed

Singhal, Dinesh K; Singhal, Raxita; Malik, Hruda N; Kumar, Surender; Kumar, Sudarshan; Mohanty, Ashok K; Kaushik, Jai K; Malakar, Dhruba

2014-01-01

Nanog is a homeodomain containing protein which plays important roles in regulation of signaling pathways for maintenance and induction of pluripotency in stem cells. Because of its unique expression in stem cells it is also regarded as pluripotency marker. In this study goat Nanog (gNanog) gene has been amplified, cloned and characterized at sequence level with successful over-expression in CHO-K1 cell line using a lentiviral based system. gNanog ORF is 903 bp long which codes for Nanog protein of size 300 amino acids (aas). Complete nucleotide sequence shows some evolutionary mutation in goat in comparision to other species. Protein sequence of goat is highly similar to other species. Overall, gNanog nucleotide sequence and predicted protein sequence showed high similarity and minimum divergence with cattle (96 % identity/4 % divergence) and buffalo (94/5 %) while low similarity and high divergence with pig (84/15 %), human (81/23 %) and mouse (69/40 %) indicating evolutionary closeness of gNanog to cattle and buffalo. gNanog lentiviral expression construct was prepared for over-expression of Nanog gene in adult goat fibroblast cells. Lentiviral expression construct of Nanog enabled continuous protein expression for induction and maintenance of pluripotency. Western blotting revealed the expression of Nanog gene at protein level which supported that the lentiviral expression system is highly promising for Nanog protein expression in differentiated goat cell.
ATNT: an enhanced system for expression of polycistronic secondary metabolite gene clusters in Aspergillus niger.

PubMed

Geib, Elena; Brock, Matthias

2017-01-01

Fungi are treasure chests for yet unexplored natural products. However, exploitation of their real potential remains difficult as a significant proportion of biosynthetic gene clusters appears silent under standard laboratory conditions. Therefore, elucidation of novel products requires gene activation or heterologous expression. For heterologous gene expression, we previously developed an expression platform in Aspergillus niger that is based on the transcriptional regulator TerR and its target promoter P terA . In this study, we extended this system by regulating expression of terR by the doxycycline inducible Tet-on system. Reporter genes cloned under the control of the target promoter P terA remained silent in the absence of doxycycline, but were strongly expressed when doxycycline was added. Reporter quantification revealed that the coupled system results in about five times higher expression rates compared to gene expression under direct control of the Tet-on system. As production of secondary metabolites generally requires the expression of several biosynthetic genes, the suitability of the self-cleaving viral peptide sequence P2A was tested in this optimised expression system. P2A allowed polycistronic expression of genes required for Asp-melanin formation in combination with the gene coding for the red fluorescent protein tdTomato. Gene expression and Asp-melanin formation was prevented in the absence of doxycycline and strongly induced by addition of doxycycline. Fluorescence studies confirmed the correct subcellular localisation of the respective enzymes. This tightly regulated but strongly inducible expression system enables high level production of secondary metabolites most likely even those with toxic potential. Furthermore, this system is compatible with polycistronic gene expression and, thus, suitable for the discovery of novel natural products.
Expression, Purification, and Structural Insights for the Human Uric Acid Transporter, GLUT9, Using the Xenopus laevis Oocytes System

PubMed Central

Clémençon, Benjamin; Lüscher, Benjamin P.; Fine, Michael; Baumann, Marc U.; Surbek, Daniel V.; Bonny, Olivier; Hediger, Matthias A.

2014-01-01

The urate transporter, GLUT9, is responsible for the basolateral transport of urate in the proximal tubule of human kidneys and in the placenta, playing a central role in uric acid homeostasis. GLUT9 shares the least homology with other members of the glucose transporter family, especially with the glucose transporting members GLUT1-4 and is the only member of the GLUT family to transport urate. The recently published high-resolution structure of XylE, a bacterial D-xylose transporting homologue, yields new insights into the structural foundation of this GLUT family of proteins. While this represents a huge milestone, it is unclear if human GLUT9 can benefit from this advancement through subsequent structural based targeting and mutagenesis. Little progress has been made toward understanding the mechanism of GLUT9 since its discovery in 2000. Before work can begin on resolving the mechanisms of urate transport we must determine methods to express, purify and analyze hGLUT9 using a model system adept in expressing human membrane proteins. Here, we describe the surface expression, purification and isolation of monomeric protein, and functional analysis of recombinant hGLUT9 using the Xenopus laevis oocyte system. In addition, we generated a new homology-based high-resolution model of hGLUT9 from the XylE crystal structure and utilized our purified protein to generate a low-resolution single particle reconstruction. Interestingly, we demonstrate that the functional protein extracted from the Xenopus system fits well with the homology-based model allowing us to generate the predicted urate-binding pocket and pave a path for subsequent mutagenesis and structure-function studies. PMID:25286413
Negative regulation of parathyroid hormone-related protein expression by steroid hormones

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

Kajitani, Takashi; Tamamori-Adachi, Mimi; Okinaga, Hiroko

Highlights: {yields} Steroid hormones repress expression of PTHrP in the cell lines where the corresponding nuclear receptors are expressed. {yields} Nuclear receptors are required for suppression of PTHrP expression by steroid hormones, except for androgen receptor. {yields} Androgen-induced suppression of PTHrP expression appears to be mediated by estrogen receptor. -- Abstract: Elevated parathyroid hormone-related protein (PTHrP) is responsible for humoral hypercalcemia of malignancy (HHM), which is of clinical significance in treatment of terminal patients with malignancies. Steroid hormones were known to cause suppression of PTHrP expression. However, detailed studies linking multiple steroid hormones to PTHrP expression are lacking. Here wemore » studied PTHrP expression in response to steroid hormones in four cell lines with excessive PTHrP production. Our study established that steroid hormones negatively regulate PTHrP expression. Vitamin D receptor, estrogen receptor {alpha}, glucocorticoid receptor, and progesterone receptor, were required for repression of PTHrP expression by the cognate ligands. A notable exception was the androgen receptor, which was dispensable for suppression of PTHrP expression in androgen-treated cells. We propose a pathway(s) involving nuclear receptors to suppress PTHrP expression.« less
Quantitative generalizations for catchment sediment yield following forest logging

Treesearch

James C. Bathurst; Andrés Iroumé

2014-01-01

Published data for temperate forests across the world are analyzed to investigate the potential for generalized quantitative expressions of catchment sediment yield impact in the years immediately following logging. Such generalizations would be useful in a variety of forestry and engineering tasks and would aid the spread of knowledge amongst both relevant...
Functional evaluation of candidate ice structuring proteins using cell-free expression systems.

PubMed

Brödel, A K; Raymond, J A; Duman, J G; Bier, F F; Kubick, S

2013-02-10

Ice structuring proteins (ISPs) protect organisms from damage or death by freezing. They depress the non-equilibrium freezing point of water and prevent recrystallization, probably by binding to the surface of ice crystals. Many ISPs have been described and it is likely that many more exist in nature that have not yet been identified. ISPs come in many forms and thus cannot be reliably identified by their structure or consensus ice-binding motifs. Recombinant protein expression is the gold standard for proving the activity of a candidate ISP. Among existing expression systems, cell-free protein expression is the simplest and gives the fastest access to the protein of interest, but selection of the appropriate cell-free expression system is crucial for functionality. Here we describe cell-free expression methods for three ISPs that differ widely in structure and glycosylation status from three organisms: a fish (Macrozoarces americanus), an insect (Dendroides canadensis) and an alga (Chlamydomonas sp. CCMP681). We use both prokaryotic and eukaryotic expression systems for the production of ISPs. An ice recrystallization inhibition assay is used to test functionality. The techniques described here should improve the success of cell-free expression of ISPs in future applications. Copyright © 2012 Elsevier B.V. All rights reserved.
Comparison of two eukaryotic systems for the expression of VP6 protein of rotavirus specie A: transient gene expression in HEK293-T cells and insect cell-baculovirus system.

PubMed

da Silva Junior, Haroldo Cid; da Silva E Mouta Junior, Sérgio; de Mendonça, Marcos César Lima; de Souza Pereira, Mirian Claudia; da Rocha Nogueira, Alanderson; de Azevedo, Maria Luiza Borges; Leite, José Paulo Gagliardi; de Moraes, Márcia Terezinha Baroni

2012-09-01

The VP6 protein of rotavirus A (RVA) is a target antigen used for diagnostic assays and also for the development of new RVA vaccines. We have compared the expression of VP6 protein in human embryonic kidney (HEK293-T) cells with results obtained using a well-established insect cell-baculovirus system. The recombinant VP6 (rVP6) expressed in HEK293-T cells did not present degradation and also retained the ability to form trimers. In the insect cell-baculovirus system, rVP6 was expressed at higher levels and with protein degradation as well as partial loss of ability to form trimers was observed. Therefore, HEK293-T cells represent a less laborious alternative system than insect cells for expression of rVP6 from human RVA.
Dependence of Initial Oxygen Concentration on Ozone Yield Using Inductive Energy Storage System Pulsed Power Generator

NASA Astrophysics Data System (ADS)

Go, Tomio; Tanaka, Yasushi; Yamazaki, Nobuyuki; Mukaigawa, Seiji; Takaki, Koichi; Fujiwara, Tamiya

Dependence of initial oxygen concentration on ozone yield using streamer discharge reactor driven by an inductive energy storage system pulsed power generator is described in this paper. Fast recovery type diodes were employed as semiconductor opening switch to interrupt a circuit current within 100 ns. This rapid current change produced high-voltage short pulse between a secondary energy storage inductor. The repetitive high-voltage short pulse was applied to a 1 mm diameter center wire electrode placed in a cylindrical pulse corona reactor. The streamer discharge successfully occurred between the center wire electrode and an outer cylinder ground electrode of 2 cm inner diameter. The ozone was produced with the streamer discharge and increased with increasing pulse repetition rate. The ozone yield changed in proportion to initial oxygen concentration contained in the injected gas mixture at 800 ns forward pumping time of the current. However, the decrease of the ozone yield by decreasing oxygen concentration in the gas mixture at 180 ns forward pumping time of the current was lower than the decrease at 800 ns forward pumping time of the current. This dependence of the initial oxygen concentration on ozone yield at 180 ns forward pumping time is similar to that of dielectric barrier discharge reactor.
Stable long-term indigo production by overexpression of dioxygenase genes using a chromosomal integrated cascade expression circuit.

PubMed

Royo, Jose Luis; Moreno-Ruiz, Emilia; Cebolla, Angel; Santero, Eduardo

2005-03-16

In our laboratory we have analyzed different factors to maximize the yield in heterologous protein expression for long-term cultivation, by combination of an efficient cascade expression system and stable integration in the bacterial chromosome. In this work, we have explored this system for the production of indigo dye as a model for biotechnological production, by expressing in Escherichia coli the thnA1A2A3A4 genes from Sphingomonas macrogolitabida strain TFA, which encode the components of a tetralin dioxygenase activity. We compared Ptac, and the Pm-based cascade expression circuit in a multicopy plasmid and stably integrated into the bacterial chromosome. Plasmid-based expression systems resulted in instability of indigo production when serially diluted batch experiments were performed without a selective pressure. This problem was solved by integrating the expression module in the chromosome. Despite the gene dosage reduction, the synergic effect of the cascade expression system produced comparable expression to the dioxygenase activity in the plasmid configuration but could be stably maintained for at least 5 days. Here, we show that the cascade amplification circuit integrated in the chromosome could be an excellent system for tight control and stable production of recombinant products.
Screening Fusion Tags for Improved Recombinant Protein Expression in E. coli with the Expresso® Solubility and Expression Screening System.

PubMed

Steinmetz, Eric J; Auldridge, Michele E

2017-11-01

The simplicity, speed, and low cost of bacterial culture make E. coli the system of choice for most initial trials of recombinant protein expression. However, many heterologous proteins are either poorly expressed in bacteria, or are produced as incorrectly folded, insoluble aggregates that lack the activity of the native protein. In many cases, fusion to a partner protein can allow for improved expression and/or solubility of a difficult target protein. Although several different fusion partners have gained favor, none are universally effective, and identifying the one that best improves soluble expression of a given target protein is an empirical process. This unit presents a strategy for parallel screening of fusion partners for enhanced expression or solubility. The Expresso® Solubility and Expression Screening System includes a panel of seven distinct fusion partners and utilizes an extremely simple cloning strategy to enable rapid screening and identification of the most effective fusion partner. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.
Os11Gsk gene from a wild rice, Oryza rufipogon improves yield in rice.

PubMed

Thalapati, Sudhakar; Batchu, Anil K; Neelamraju, Sarla; Ramanan, Rajeshwari

2012-06-01

Chromosomal segments from wild rice species Oryza rufipogon, introgressed into an elite indica rice restorer line (KMR3) using molecular markers, resulted in significant increase in yield. Here we report the transcriptome analysis of flag leaves and fully emerged young panicles of one of the high yielding introgression lines IL50-7 in comparison to KMR3. A 66-fold upregulated gene Os11Gsk, which showed no transcript in KMR3 was highly expressed in O. rufipogon and IL50-7. A 5-kb genomic region including Os11Gsk and its flanking regions could be PCR amplified only from IL50-7, O. rufipogon, japonica varieties of rice-Nipponbare and Kitaake but not from the indica varieties, KMR3 and Taichung Native-1. Three sister lines of IL50-7 yielding higher than KMR3 showed presence of Os11Gsk, whereas the gene was absent in three other ILs from the same cross having lower yield than KMR3, indicating an association of the presence of Os11Gsk with high yield. Southern analysis showed additional bands in the genomic DNA of O. rufipogon and IL50-7 with Os11Gsk probe. Genomic sequence analysis of ten highly co-expressed differentially regulated genes revealed that two upregulated genes in IL50-7 were derived from O. rufipogon and most of the downregulated genes were either from KMR3 or common to KMR3, IL50-7, and O. rufipogon. Thus, we show that Os11Gsk is a wild rice-derived gene introduced in KMR3 background and increases yield either by regulating expression of functional genes sharing homology with it or by causing epigenetic modifications in the introgression line.
The Facial Expression Coding System (FACES): Development, Validation, and Utility

ERIC Educational Resources Information Center

Kring, Ann M.; Sloan, Denise M.

2007-01-01

This article presents information on the development and validation of the Facial Expression Coding System (FACES; A. M. Kring & D. Sloan, 1991). Grounded in a dimensional model of emotion, FACES provides information on the valence (positive, negative) of facial expressive behavior. In 5 studies, reliability and validity data from 13 diverse…
Duplication of an upstream silencer of FZP increases grain yield in rice.

PubMed

Bai, Xufeng; Huang, Yong; Hu, Yong; Liu, Haiyang; Zhang, Bo; Smaczniak, Cezary; Hu, Gang; Han, Zhongmin; Xing, Yongzhong

2017-11-01

Transcriptional silencer and copy number variants (CNVs) are associated with gene expression. However, their roles in generating phenotypes have not been well studied. Here we identified a rice quantitative trait locus, SGDP7 (Small Grain and Dense Panicle 7). SGDP7 is identical to FZP (FRIZZY PANICLE), which represses the formation of axillary meristems. The causal mutation of SGDP7 is an 18-bp fragment, named CNV-18bp, which was inserted ~5.3 kb upstream of FZP and resulted in a tandem duplication in the cultivar Chuan 7. The CNV-18bp duplication repressed FZP expression, prolonged the panicle branching period and increased grain yield by more than 15% through substantially increasing the number of spikelets per panicle (SPP) and slightly decreasing the 1,000-grain weight (TGW). The transcription repressor OsBZR1 binds the CGTG motifs in CNV-18bp and thereby represses FZP expression, indicating that CNV-18bp is the upstream silencer of FZP. These findings showed that the silencer CNVs coordinate a trade-off between SPP and TGW by fine-tuning FZP expression, and balancing the trade-off could enhance yield potential.
An updated whole stand growth and yield system for planted longleaf pine in southwest Georgia

Treesearch

John R. Brooks; Steven B. Jack

2016-01-01

An updated whole stand growth and yield system for planted longleaf pine (Pinus palustris) wasÂ developed from permanent plot data collected annually over a 13 to 16 year period. The data set consists ofÂ 15 intensively managed longleaf pine plantations that are located in Lee, Worth, Mitchell, and Baker countiesÂ in southwest Georgia. Stand survival, dominant height,...
Co-expression of AaPMT and AaTRI effectively enhances the yields of tropane alkaloids in Anisodus acutangulus hairy roots

PubMed Central

2011-01-01

Background Tropane alkaloids (TA) including anisodamine, anisodine, hyoscyamine and scopolamine are a group of important anticholinergic drugs with rapidly increasing market demand, so it is significant to improve TA production by biotechnological approaches. Putrescine N-methyltransferase (PMT) was considered as the first rate-limiting upstream enzyme while tropinone reductase I (TRI) was an important branch-controlling enzyme involved in TA biosynthesis. However, there is no report on simultaneous introduction of PMT and TRI genes into any TA-producing plant including Anisodus acutangulus (A. acutangulus), which is a Solanaceous perennial plant that is endemic to China and is an attractive resource plant for production of TA. Results In this study, 21 AaPMT and AaTRI double gene transformed lines (PT lines), 9 AaPMT single gene transformed lines (P lines) and 5 AaTRI single gene transformed lines (T lines) were generated. RT-PCR and real-time fluorescence quantitative analysis results revealed that total AaPMT (AaPMT T) and total AaTRI (AaTRI T) gene transcripts in transgenic PT, P and T lines showed higher expression levels than native AaPMT (AaPMT E) and AaTRI (AaTRI E) gene transcripts. As compared to the control and single gene transformed lines (P or T lines), PT transgenic hairy root lines produced significantly higher levels of TA. The highest yield of TA was detected as 8.104 mg/g dw in line PT18, which was 8.66, 4.04, and 3.11-times higher than those of the control (0.935 mg/g dw), P3 (highest in P lines, 2.004 mg/g dw) and T12 (highest in T lines, 2.604 mg/g dw), respectively. All the tested samples were found to possess strong radical scavenging capacity, which were similar to control. Conclusion In the present study, the co-expression of AaPMT and AaTRI genes in A. acutangulus hairy roots significantly improved the yields of TA and showed higher antioxidant activity than control because of higher total TA content, which is the first report on
A highly tunable system for the simultaneous expression of multiple enzymes in Saccharomyces cerevisiae.

PubMed

Ito, Yoichiro; Yamanishi, Mamoru; Ikeuchi, Akinori; Matsuyama, Takashi

2015-01-16

Control of the expression levels of multiple enzymes in transgenic yeasts is essential for the effective production of complex molecules through fermentation. Here, we propose a tunable strategy for the control of expression levels based on the design of terminator regions and other gene-expression control elements in Saccharomyces cerevisiae. Our genome-integrated system, which is capable of producing high expression levels over a wide dynamic range, will broadly enable metabolic engineering and synthetic biology. We demonstrated that the activities of multiple cellulases and the production of ethanol were doubled in a transgenic yeast constructed with our system compared with those achieved with a standard expression system.
Polyelectrolyte scaling laws for microgel yielding near jamming.

PubMed

Bhattacharjee, Tapomoy; Kabb, Christopher P; O'Bryan, Christopher S; Urueña, Juan M; Sumerlin, Brent S; Sawyer, W Gregory; Angelini, Thomas E

2018-02-28

Micro-scale hydrogel particles, known as microgels, are used in industry to control the rheology of numerous different products, and are also used in experimental research to study the origins of jamming and glassy behavior in soft-sphere model systems. At the macro-scale, the rheological behaviour of densely packed microgels has been thoroughly characterized; at the particle-scale, careful investigations of jamming, yielding, and glassy-dynamics have been performed through experiment, theory, and simulation. However, at low packing fractions near jamming, the connection between microgel yielding phenomena and the physics of their constituent polymer chains has not been made. Here we investigate whether basic polymer physics scaling laws predict macroscopic yielding behaviours in packed microgels. We measure the yield stress and cross-over shear-rate in several different anionic microgel systems prepared at packing fractions just above the jamming transition, and show that our data can be predicted from classic polyelectrolyte physics scaling laws. We find that diffusive relaxations of microgel deformation during particle re-arrangements can predict the shear-rate at which microgels yield, and the elastic stress associated with these particle deformations predict the yield stress.

Photosensitized electron transfer processes in SiO2 colloids and sodium lauryl sulfate micellar systems: Correlation of quantum yields with interfacial surface potentials

PubMed Central

Laane, Colja; Willner, Itamar; Otvos, John W.; Calvin, Melvin

1981-01-01

The effectiveness of negatively charged colloidal SiO2 particles in controlling photosensitized electron transfer reactions has been studied and compared with that of the negatively charged sodium lauryl sulfate (NaLauSO4) micellar system. In particular, the photosensitized reduction of the zwitterionic electron acceptor propylviologen sulfonate (PVS0) with tris(2,2′-bipyridinium)ruthenium(II) [Ru(bipy)32+] as the sensitizer and triethanolamine as the electron donor is found to have a quantum yield of 0.033 for formation of the radical anion (PVS[unk]) in the SiO2 colloid compared with 0.005 in the homogeneous system and 0.0086 in a NaLauSO4 micellar solution. The higher quantum yields obtained with the SiO2 colloidal system are attributed to substantial stabilization against back reaction of the intermediate photoproducts—i.e., Ru(bipy)33+ and PVS[unk]—by electrostatic repulsion of the reduced electron acceptor from the negatively charged particle surface. The binding properties of the SiO2 particles and NaLauSO4 micelles were investigated by flow dialysis. The results show that the sensitizer binds to both interfaces and that the SiO2 interface is characterized by a much higher surface potential than the micellar interface (≈-170 mV vs. -85 mV). The effect of ionic strength on the surface potential was estimated from the Gouy-Chapman theory, and the measured quantum yields of photosensitized electron transfer were correlated with surface potential at different ionic strengths. This correlation shows that the quantum yield is not affected by surface potentials smaller than ≈-40 mV. At larger potentials, the quantum yield increases rapidly. The quantum yield obtained in the micellar system at different strengths fits nicely on the correlation curve for the colloid SiO2 system. These results indicate that the surface potential is the dominant factor in the quantum yield improvement for PVS0 reduction. PMID:16593095
Effects of Management Practices on Meloidogyne incognita and Snap Bean Yield.

PubMed

Smittle, D A; Johnson, A W

1982-01-01

Phenamiphos applied at 6.7 kg ai/ha through a solid set or a center pivot irrigation system with 28 mm of water effectively controlled root-knot nematodes, Meloidogyne incognita, and resulted in greater snap bean growth and yields irrespective of growing season, tillage method, or cover crop system. The percentage yield increases attributed to this method of M. incognita control over nontreated controls were 45% in the spring crop, and 90% and 409% in the fall crops following winter rye and fallow, respectively. Root galling was not affected by tillage systems or cover crop, but disk tillage resulted in over 50% reduction in bean yield compared with yields from the subsoil-bed tillage system.
PAY1 improves plant architecture and enhances grain yield in rice.

PubMed

Zhao, Lei; Tan, Lubin; Zhu, Zuofeng; Xiao, Langtao; Xie, Daoxin; Sun, Chuanqing

2015-08-01

Plant architecture, a complex of the important agronomic traits that determine grain yield, is a primary target of artificial selection of rice domestication and improvement. Some important genes affecting plant architecture and grain yield have been isolated and characterized in recent decades; however, their underlying mechanism remains to be elucidated. Here, we report genetic identification and functional analysis of the PLANT ARCHITECTURE AND YIELD 1 (PAY1) gene in rice, which affects plant architecture and grain yield in rice. Transgenic plants over-expressing PAY1 had twice the number of grains per panicle and consequently produced nearly 38% more grain yield per plant than control plants. Mechanistically, PAY1 could improve plant architecture via affecting polar auxin transport activity and altering endogenous indole-3-acetic acid distribution. Furthermore, introgression of PAY1 into elite rice cultivars, using marker-assisted background selection, dramatically increased grain yield compared with the recipient parents. Overall, these results demonstrated that PAY1 could be a new beneficial genetic resource for shaping ideal plant architecture and breeding high-yielding rice varieties. © 2015 The Authors The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.
Method for improving product yields in an anionic metalloporphyrin-based artificial photosynthesis system

DOEpatents

Shelnutt, John A.

1986-01-01

A method for improving product yields in an anionic metalloporphyrin-based artificial photosynthesis system for hydrogen generation which comprises forming an aqueous solution comprising an electron donor, methylviologen, and certain metalloporphyrins and metallochlorins, and irradiating said aqueous solution with light in the presence of a catalyst. In the photosynthesis process, solar energy is collected and stored in the form of a gas hydrogen. Ligands attached above and below the metalloporphyrin and metallochlorin plane are capable of sterically blocking photochemically inactive electrostatically bound .pi.--.pi. complexes which can develop.
Method for improving product yields in an anionic metalloporphyrin-based artificial photosynthesis system

DOEpatents

Shelnutt, J.A.

1984-11-29

A method is disclosed improving product yields in an anionic metalloporphyrin-based artificial photosynthesis system for hydrogen generation. The method comprises forming an aqueous solution comprising an electron donor, methylviologen, and certain metalloporphyrins and metallochlorins, and irradiating said aqueous solution with light in the presence of a catalyst. In the photosynthesis process, solar energy is collected and stored in the form of a hydrogen. Ligands attached above and below the metalloporphyrin and metallochlorin plane are capable of sterically blocking photochemically inactive electrostatically bound ..pi..-..pi.. complexes which can develop.
Efficient expression and purification of recombinant therapeutic protein candidates, human midkine and pleiotrophin.

PubMed

Murasugi, Akira

2013-01-01

Midkine is a heparin-binding growth factor that promotes cell growth, survival, and migration. Externally added midkine prevents ventricular remodeling and improves long-term survival after myocardial infarction in the mouse. Preclinical testing of this protein is in progress. Externally added pleiotrophin, a member of the midkine protein family, promotes functional recovery after neural transplantation in rats. Thus, pleiotrophin is also a candidate therapeutic protein. Large amounts of these proteins were obtained by using the heterologous protein expression system of Pichia pastoris, and the recombinant P. pastoris clones were cultured in a controlled fermentor. Intracellular expression yielded about 300 mg/L recombinant human (rh)-midkine, which was extracted, renatured, and purified. From 1 L of the culture, 64 mg of rh-midkine was purified. Secretory expression induced by the midkine secretion signal resulted in about 100 mg of rhmidkine in 1 L of the culture supernatant, but over 70% of the rh-midkine had yeast-specific glycosylation. Three threonyl residues that are targets for glycosylation were substituted with alanyl residues, and nonglycosylated, active rh-midkine was obtained. In secretory expression using α-mating factor prepro-sequence, about 640 mg/L rh-midkine was obtained, but it was partially truncated. Therefore, a protease-deficient host was used, and about 360 mg/L intact rh-midkine was then obtained. The rh-midkine was recovered and purified, with 70% final yield. All purified rh-midkine, regardless of expression method, was able to promote mammalian cell proliferation. In secretory expression of rh-pleiotrophin using α- mating factor prepro-sequence, 260 mg/L rh-pleiotrophin could be secreted. The rh-pleiotrophin was recovered and efficiently purified with 72% final yield.
Diagnostic Yield and Safety of Brain Biopsy for Suspected Primary Central Nervous System Angiitis.

PubMed

Torres, Jose; Loomis, Caitlin; Cucchiara, Brett; Smith, Michelle; Messé, Steven

2016-08-01

The utility and safety of brain biopsy for suspected primary angiitis of the central nervous system (PACNS) are uncertain. Factors predictive of a positive biopsy have not been well described. Our aim was to evaluate the diagnostic yield and safety of brain biopsy in suspected PACNS and determine whether any prebiopsy variables are associated with a positive biopsy. This is a retrospective study of consecutive patients who underwent diagnostic brain biopsy for PACNS at a single institution. The relationship between biopsy yield and patient demographics, surgical technique, laboratory testing, neuroimaging, biopsy characteristics, and prebiopsy immunosuppressive therapy were examined. PACNS was confirmed in 9 of 79 patients (11%). Biopsy identified alternative diagnoses in 24 patients (30%), with cerebral amyloid angiopathy (8 patients), encephalitis (5 patients), demyelination (3 patients), and CNS lymphoma (3 patients) most commonly found. There was no correlation between a positive biopsy and cerebrospinal fluid results, neuroimaging, surgical technique, biopsy characteristics, or preoperative immunosuppressive therapy. Smaller biopsies (P=0.02) and closed procedures (P=0.013) were less likely to yield a diagnosis. Postoperative complications occurred in 13 patients (16%), 3 (4%) of which were serious. Brain biopsy leads to pathological confirmation of vasculitis in a minority of suspected PACNS cases but alternative diagnoses are often identified. Importantly, rare but meaningful complications may occur. © 2016 American Heart Association, Inc.
The effect of lactation number, stage, length, and milking frequency on milk yield in Korean Holstein dairy cows using automatic milking system

PubMed Central

Vijayakumar, Mayakrishnan; Park, Ji Hoo; Ki, Kwang Seok; Lim, Dong Hyun; Kim, Sang Bum; Park, Seong Min; Jeong, Ha Yeon; Park, Beom Young; Kim, Tae Il

2017-01-01

Objective The aim of the current study was to describe the relationship between milk yield and lactation number, stage, length and milking frequency in Korean Holstein dairy cows using an automatic milking system (AMS). Methods The original data set consisted of observations from April to October 2016 of 780 Holstein cows, with a total of 10,751 milkings. Each time a cow was milked by an AMS during the 24 h, the AMS management system recorded identification numbers of the AMS unit, the cow being milking, date and time of the milking, and milk yield (kg) as measured by the milk meters installed on each AMS unit, date and time of the lactation, lactation stage, milking frequency (NoM). Lactation stage is defined as the number of days milking per cows per lactation. Milk yield was calculated per udder quarter in the AMS and was added to 1 record per cow and trait for each milking. Milking frequency was measured the number of milkings per cow per 24 hour. Results From the study results, a significant relationship was found between the milk yield and lactation number (p<0.001), with the maximum milk yield occurring in the third lactation cows. We recorded the highest milk yield, in a greater lactation length period of early stage (55 to 90 days) at a 4× milking frequency/d, and the lowest milk yield was observed in the later stage (>201 days) of cows. Also, milking frequency had a significant influence on milk yield (p<0.001) in Korean Holstein cows using AMS. Conclusion Detailed knowledge of these factors such as lactation number, stage, length, and milking frequency associated with increasing milk yield using AMS will help guide future recommendations to producers for maximizing milk yield in Korean Dairy industries. PMID:28423887
Towards Better Simulation of US Maize Yield Responses to Climate in the Community Earth System Model

NASA Astrophysics Data System (ADS)

Peng, B.; Guan, K.; Chen, M.; Lawrence, D. M.; Jin, Z.; Bernacchi, C.; Ainsworth, E. A.; DeLucia, E. H.; Lombardozzi, D. L.; Lu, Y.

2017-12-01

Global food security is undergoing continuing pressure from increased population and climate change despites the potential advancement in breeding and management technologies. Earth system models (ESMs) are essential tools to study the impacts of historical and future climate on regional and global food production, as well as to assess the effectiveness of possible adaptations and their potential feedback to climate. Here we developed an improved maize representation within the Community Earth System Model (CESM) by combining the strengths of both the Community Land Model version 4.5 (CLM4.5) and the Agricultural Production Systems sIMulator (APSIM) models. Specifically, we modified the maize planting scheme, incorporated the phenology scheme adopted from the APSIM model, added a new carbon allocation scheme into CLM4.5, and improved the estimation of canopy structure parameters including leaf area index (LAI) and canopy height. Unique features of the new model (CLM-APSIM) include more detailed phenology stages, an explicit implementation of the impacts of various abiotic environmental stresses (including nitrogen, water, temperature and heat stresses) on maize phenology and carbon allocation, as well as an explicit simulation of grain number and grain size. We conducted a regional simulation of this new model over the US Corn Belt during 1990 to 2010. The simulated maize yield as well as its responses to climate (growing season mean temperature and precipitation) are benchmarked with data from UADA NASS statistics. Our results show that the CLM-APSIM model outperforms the CLM4.5 in simulating county-level maize yield production and reproduces more realistic yield responses to climate variations than CLM4.5. However, some critical processes (such as crop failure due to frost and inundation and suboptimal growth condition due to biotic stresses) are still missing in both CLM-APSIM and CLM4.5, making the simulated yield responses to climate slightly deviate from the
Tradeoffs between vigor and yield for crops grown under different management systems

NASA Astrophysics Data System (ADS)

Simic Milas, Anita; Keller Vincent, Robert; Romanko, Matthew; Feitl, Melina; Rupasinghe, Prabha

2016-04-01

Remote sensing can provide an effective means for rapid and non-destructive monitoring of crop status and biochemistry. Monitoring pattern of traditional vigor algorithms generated from Landsat 8 OLI satellite data represents a robust method that can be widely used to differentiate the status of crops, as well as to monitor nutrient uptake functionality of differently treated seeds grown under different managements. This study considers 24 factorial parcels of winter wheat in 2013, corn in 2014, and soybeans in 2015, grown under four different types of agricultural management. The parcels are located at the Kellogg Biological Station, Long-Term Ecological Research site in the State of Michigan USA. At maturity, the organic crops exhibit significantly higher vigor and significantly lower yield than conventionally managed crops under different treatments. While organic crops invest in their metabolism at the expense of their yield, the conventional crops manage to increase their yield at the expense of their vigor. Landsat 8 OLI is capable of 1) differentiating the biochemical status of crops under different treatments at maturity, and 2) monitoring the tradeoff between crop yield and vigor that can be controlled by the seed treatments and proper conventional applications, with the ultimate goal of increasing food yield and food availability, and 3) distinguishing between organic and conventionally treated crops. Timing, quantity and types of herbicide applications have a great impact on early and pre-harvest vigor, maturity and yield of conventionally treated crops. Satellite monitoring using Landsat 8 is an optimal tool for coordinating agricultural applications, soil practices and genetic coding of the crop to produce higher yield as well as have early crop maturity, desirable in northern climates.
[Contrast of Z-Pinch X-Ray Yield Measure Technique].

PubMed

Li, Mo; Wang, Liang-ping; Sheng, Liang; Lu, Yi

2015-03-01

Resistive bolometer and scintillant detection system are two mainly Z-pinch X-ray yield measure techniques which are based on different diagnostic principles. Contrasting the results from two methods can help with increasing precision of X-ray yield measurement. Experiments with different load material and shape were carried out on the "QiangGuang-I" facility. For Al wire arrays, X-ray yields measured by the two techniques were largely consistent. However, for insulating coating W wire arrays, X-ray yields taken from bolometer changed with load parameters while data from scintillant detection system hardly changed. Simulation and analysis draw conclusions as follows: (1) Scintillant detection system is much more sensitive to X-ray photons with low energy and its spectral response is wider than the resistive bolometer. Thus, results from the former method are always larger than the latter. (2) The responses of the two systems are both flat to Al plasma radiation. Thus, their results are consistent for Al wire array loads. (3) Radiation form planar W wire arrays is mainly composed of sub-keV soft X-ray. X-ray yields measured by the bolometer is supposed to be accurate because of the nickel foil can absorb almost all the soft X-ray. (4) By contrast, using planar W wire arrays, data from scintillant detection system hardly change with load parameters. A possible explanation is that while the distance between wires increases, plasma temperature at stagnation reduces and spectra moves toward the soft X-ray region. Scintillator is much more sensitive to the soft X-ray below 200 eV. Thus, although the total X-ray yield reduces with large diameter load, signal from the scintillant detection system is almost the same. (5) Both Techniques affected by electron beams produced by the loads.
Sustainable yield of a karst aquifer system: a case study of Jinan springs in northern China

NASA Astrophysics Data System (ADS)

Kang, Fengxin; Jin, Menggui; Qin, Pinrui

2011-06-01

Based on the long-term monitoring data of rainfall, groundwater levels, groundwater abstraction, spring flow rates and groundwater quality, an assessment has been undertaken of the sustainable yield of a karst aquifer system in Shandong Province, northern China, to maintain perennial outflow of the karst springs while meeting water demands. One of the fundamental indicators for sustainable yield of groundwater is identified as maximum allowable water-level drawdown. A regional three-dimensional finite-difference numerical model has been developed to optimize the schemes associated with well fields and their locations and sustainable yields, in the Jinan spring catchment and its adjacent karst groundwater catchments, with the aim of maintaining the water level higher than the allowable lowest water level of 27.5 m above sea level. Furthermore, measures necessary to move towards sustainable use of the karst groundwater are outlined, drawing on contingency plans of water-source replacement and artificial recharge, dual water supply (based in water quality), use of the spring waters themselves, and groundwater quality protection.
Absolute quantum yield measurement of powder samples.

PubMed

Moreno, Luis A

2012-05-12

Measurement of fluorescence quantum yield has become an important tool in the search for new solutions in the development, evaluation, quality control and research of illumination, AV equipment, organic EL material, films, filters and fluorescent probes for bio-industry. Quantum yield is calculated as the ratio of the number of photons absorbed, to the number of photons emitted by a material. The higher the quantum yield, the better the efficiency of the fluorescent material. For the measurements featured in this video, we will use the Hitachi F-7000 fluorescence spectrophotometer equipped with the Quantum Yield measuring accessory and Report Generator program. All the information provided applies to this system. Measurement of quantum yield in powder samples is performed following these steps: 1. Generation of instrument correction factors for the excitation and emission monochromators. This is an important requirement for the correct measurement of quantum yield. It has been performed in advance for the full measurement range of the instrument and will not be shown in this video due to time limitations. 2. Measurement of integrating sphere correction factors. The purpose of this step is to take into consideration reflectivity characteristics of the integrating sphere used for the measurements. 3. Reference and Sample measurement using direct excitation and indirect excitation. 4. Quantum Yield calculation using Direct and Indirect excitation. Direct excitation is when the sample is facing directly the excitation beam, which would be the normal measurement setup. However, because we use an integrating sphere, a portion of the emitted photons resulting from the sample fluorescence are reflected by the integrating sphere and will re-excite the sample, so we need to take into consideration indirect excitation. This is accomplished by measuring the sample placed in the port facing the emission monochromator, calculating indirect quantum yield and correcting the direct
Effect of agitation and terminal subcultures on yield and speed of detection of the Oxoid Signal blood culture system versus the BACTEC radiometric system

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

Weinstein, M.P.; Mirrett, S.; Reimer, L.G.

1989-03-01

In an initial evaluation, we found the Oxoid Signal blood culture system inferior to the BACTEC radiometric system for detection of some microorganisms causing septicemia. To determine whether modified processing of the Oxoid Signal blood culture system could improve its yield and speed of detecting positive cultures relative to the BACTEC radiometric system, we agitated all Oxoid bottles during the first 24 to 48 h of incubation and performed aerobic and anaerobic subcultures of all Oxoid bottles negative after 7 days of incubation. These modifications improved the overall performance of the Oxoid system, particularly with regard to the yield ofmore » streptococci, members of the family Enterobacteriaceae, and Haemophilus, Neisseria, and Acinetobacter spp. The speed of detecting positive cultures also was improved, especially within the first 24 h of incubation. However, the BACTEC system still detected more positive cultures (P less than 0.005), especially of obligate aerobes such as Pseudomonas aeruginosa (P less than 0.05) and yeasts (P less than 0.005). The BACTEC system also detected positive cultures earlier than the Oxoid system (e.g., at 24 h of incubation, 70.5% of BACTEC positive cultures detected versus 62.1% of Oxoid positive cultures detected). Further modifications of the Oxoid system which might include a revised medium, additional processing modifications, altered headspace atmosphere, or a complementary second broth medium should be considered, since the system is attractive in concept and is easy to use in the clinical laboratory.« less
Impact of age and vector construct on striatal and nigral transgene expression

PubMed Central

Polinski, Nicole K; Manfredsson, Fredric P; Benskey, Matthew J; Fischer, D Luke; Kemp, Christopher J; Steece-Collier, Kathy; Sandoval, Ivette M; Paumier, Katrina L; Sortwell, Caryl E

2016-01-01

Therapeutic protein delivery using viral vectors has shown promise in preclinical models of Parkinson’s disease (PD) but clinical trial success remains elusive. This may partially be due to a failure to include advanced age as a covariate despite aging being the primary risk factor for PD. We investigated transgene expression following intracerebral injections of recombinant adeno-associated virus pseudotypes 2/2 (rAAV2/2), 2/5 (rAAV2/5), 2/9 (rAAV2/9), and lentivirus (LV) expressing green fluorescent protein (GFP) in aged versus young adult rats. Both rAAV2/2 and rAAV2/5 yielded lower GFP expression following injection to either the aged substantia nigra or striatum. rAAV2/9-mediated GFP expression was deficient in the aged striatonigral system but displayed identical transgene expression between ages in the nigrostriatal system. Young and aged rats displayed equivalent GFP levels following LV injection to the striatonigral system but LV-delivered GFP was deficient in delivering GFP to the aged nigrostriatal system. Notably, age-related transgene expression deficiencies revealed by protein quantitation were poorly predicted by GFP-immunoreactive cell counts. Further, in situ hybridization for the viral CβA promoter revealed surprisingly limited tropism for astrocytes compared to neurons. Our results demonstrate that aging is a critical covariate to consider when designing gene therapy approaches for PD. PMID:27933309
Induction of Systemic Resistance against Aphids by Endophytic Bacillus velezensis YC7010 via Expressing PHYTOALEXIN DEFICIENT4 in Arabidopsis

PubMed Central

Rashid, Md. Harun-Or-; Khan, Ajmal; Hossain, Mohammad T.; Chung, Young R.

2017-01-01

Aphids are the most destructive insect pests. They suck the sap and transmit plant viruses, causing widespread yield loss of many crops. A multifunctional endophytic bacterial strain Bacillus velezensis YC7010 has been found to induce systemic resistance against bacterial and fungal pathogens of rice. However, its activity against insects attack and underlying cellular and molecular defense mechanisms are not elucidated yet. Here, we show that root drenching of Arabidopsis seedlings with B. velezensis YC7010 can induce systemic resistance against green peach aphid (GPA), Myzus persicae. Treatment of bacterial suspension of B. velezensis YC7010 at 2 × 107 CFU/ml to Arabidopsis rhizosphere induced higher accumulation of hydrogen peroxide, cell death, and callose deposition in leaves compared to untreated plants at 6 days after infestation of GPA. Salicylic acid, jasmonic acid, ethylene, and abscisic acid were not required to confer defense against GPA in Arabidopsis plants treated by B. velezensis YC7010. Bacterial treatment with B. velezensis YC7010 significantly reduced settling, feeding and reproduction of GPA on Arabidopsis leaves via strongly expressing senescence-promoting gene PHYTOALEXIN DEFICIENT4 (PAD4) while suppressing BOTRYTIS-INDUCED KINASE1 (BIK1). These results indicate that B. velezensis YC7010-induced systemic resistance to the GPA is a hypersensitive response mainly dependent on higher expression of PAD4 with suppression of BIK1, resulting in more accumulation of hydrogen peroxide, cell death, and callose deposition in Arabidopsis. PMID:28261260
[Effects of reduced N application rate on yield and nutrient uptake and utilization in maize-soybean relay strip intercropping system].

PubMed

Yong, Tai-Wen; Liu, Xiao-Ming; Wen-Yu, Liu; Su, Ben-Ying; Song, Chun; Yang, Feng; Wang, Xiao-Chun; Yang, Wen-Yu

2014-02-01

A field experiment with three N application rates (0, 180, 240 N kg x hm(-2), representing zero, reduced and conventional N application, respectively) and three planting patterns (maize monoculture, soybean monoculture and maize-soybean relay strip intercropping) was conducted to reveal the effects of cropping patterns and N application rates on yield, nutrient uptake and nitrogen use efficiency of maize and soybean. The results showed that the grain yield, N, P and K uptake and harvest index of the intercropped maize reduced slightly compared with the monoculture maize, however these indices of the intercropped soybean increased significantly compared with the monoculture. With the increase in nitrogen fertilizer application, the excellence of relay strip intercropping was weakened in the maize-soybean intercropping system. The grain yield, economic coefficient, N, P and K uptake, harvest index, N agronomy efficiency and N uptake efficiency of maize and soybean increased significantly at the reduced nitrogen rate (180 N kg x hm(-2)), but the rate of soil N contribution declined, compared with the conventional rate of N application by local farmers (240 N kg x hm(-2)). In the reduced nitrogen rate treatment, total soil N and P contents of the maize strip reduced, whereas the total soil N, P and K contents of soybean strip and the total K content of maize strip increased compared with the zero N application treatment. With the reduced N application, the annual total grain yield, N, P and K uptake of above-ground biomass in the maize-soybean relay strip intercropping system were higher than in the monoculture, and the land equivalent ratio (LER) was 2.28. N uptake efficiency of maize in the relay strip intercropping system was 20.2% higher than in the maize monoculture, and the index of soybean was 30.5% lower than in the monoculture. The rate of soil N contribution in the relay strip intercropping system was 20.0% and 8.8% lower than in the maize and soybean
21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system. (a...
21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system. (a...
21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system. (a...

21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system. (a...
Benefits of seasonal forecasts of crop yields

NASA Astrophysics Data System (ADS)

Sakurai, G.; Okada, M.; Nishimori, M.; Yokozawa, M.

2017-12-01

Major factors behind recent fluctuations in food prices include increased biofuel production and oil price fluctuations. In addition, several extreme climate events that reduced worldwide food production coincided with upward spikes in food prices. The stabilization of crop yields is one of the most important tasks to stabilize food prices and thereby enhance food security. Recent development of technologies related to crop modeling and seasonal weather forecasting has made it possible to forecast future crop yields for maize and soybean. However, the effective use of these technologies remains limited. Here we present the potential benefits of seasonal crop-yield forecasts on a global scale for choice of planting day. For this purpose, we used a model (PRYSBI-2) that can well replicate past crop yields both for maize and soybean. This model system uses a Bayesian statistical approach to estimate the parameters of a basic process-based model of crop growth. The spatial variability of model parameters was considered by estimating the posterior distribution of the parameters from historical yield data by using the Markov-chain Monte Carlo (MCMC) method with a resolution of 1.125° × 1.125°. The posterior distributions of model parameters were estimated for each spatial grid with 30 000 MCMC steps of 10 chains each. By using this model and the estimated parameter distributions, we were able to estimate not only crop yield but also levels of associated uncertainty. We found that the global average crop yield increased about 30% as the result of the optimal selection of planting day and that the seasonal forecast of crop yield had a large benefit in and near the eastern part of Brazil and India for maize and the northern area of China for soybean. In these countries, the effects of El Niño and Indian Ocean dipole are large. The results highlight the importance of developing a system to forecast global crop yields.
Highly repressible expression system for cloning genes that specify potentially toxic proteins.

PubMed Central

O'Connor, C D; Timmis, K N

1987-01-01

A highly repressible expression vector system that allows the cloning of potentially deleterious genes has been constructed. Undesired expression of a cloned gene was prevented (i) at the level of initiation of transcription, by the presence of the strong but highly repressible leftward promoter of bacteriophage lambda, lambda pL, and (ii) at the level of transcript elongation or translation, through synthesis of antisense RNA complementary to the mRNA of the cloned gene. The system was tested by measuring the inhibition of expression of traT, the gene for the TraT major outer membrane lipoprotein. Direct detection and functional assays indicated that an essentially complete inhibition of traT expression was obtained. As a further test of the system, the gene encoding the EcoRI restriction endonuclease was cloned in the absence of the gene of the corresponding protective EcoRI modification methylase. Transformants harboring this construct were only viable when both repression controls were operational. Images PMID:2443481
PARP-1 regulates the expression of caspase-11

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

Yoo, Lang; Hong, Seokheon; Shin, Ki Soon

2011-05-13

Highlights: {yields} Knockdown of PARP-1 suppresses the LPS-induced expression of caspase-11. {yields} Knockdown of PARP-1 suppresses the caspase-11 promoter activity following LPS stimulation. {yields} PARP-1 is recruited to the caspase-11 promoter region containing NF-{kappa}B-binding sites following LPS stimulation. {yields} PARP-1 inhibitors cannot suppress the caspase-11 induction. {yields} PARP-1 does not suppress IFN-{gamma}-induced expression of caspase-11. -- Abstract: Poly(ADP-ribose) polymerase-1 (PARP-1) is a multifunctional enzyme that regulates DNA repair, cell death and transcription of inflammatory proteins. In the present study, we present evidence that PARP-1 regulates the expression of caspase-11 following lipopolysaccharide (LPS) stimulation. Knockdown of PARP-1 suppressed the LPS-induced expressionmore » of caspase-11 at both mRNA and protein levels as well as caspase-11 promoter activity. Importantly, PARP-1 was recruited to the caspase-11 promoter region containing predicted nuclear factor (NF)-{kappa}B-binding sites when examined by chromatin immunoprecipitation assay. However, knockdown of PARP-1 did not suppress the expression of caspase-11 induced by interferon-{gamma} that activates signal transducer and activator of transcription 1 but not NF-{kappa}B. PARP-1 enzymatic activity was not required for the caspase-11 upregulation since pharmacological inhibitors of PARP-1 did not suppress the induction of caspase-11. Our results suggest that PARP-1, as a transcriptional cofactor for NF-{kappa}B, regulates the induction of caspase-11 at a transcriptional level.« less
Yield performance and stability of CMS-based triticale hybrids.

PubMed

Mühleisen, Jonathan; Piepho, Hans-Peter; Maurer, Hans Peter; Reif, Jochen Christoph

2015-02-01

CMS-based triticale hybrids showed only marginal midparent heterosis for grain yield and lower dynamic yield stability compared to inbred lines. Hybrids of triticale (×Triticosecale Wittmack) are expected to possess outstanding yield performance and increased dynamic yield stability. The objectives of the present study were to (1) examine the optimum choice of the biometrical model to compare yield stability of hybrids versus lines, (2) investigate whether hybrids exhibit a more pronounced grain yield performance and yield stability, and (3) study optimal strategies to predict yield stability of hybrids. Thirteen female and seven male parental lines and their 91 factorial hybrids as well as 30 commercial lines were evaluated for grain yield in up to 20 environments. Hybrids were produced using a cytoplasmic male sterility (CMS)-inducing cytoplasm that originated from Triticumtimopheevii Zhuk. We found that the choice of the biometrical model can cause contrasting results and concluded that a group-by-environment interaction term should be added to the model when estimating stability variance of hybrids and lines. midparent heterosis for grain yield was on average 3 % with a range from -15.0 to 11.5 %. No hybrid outperformed the best inbred line. Hybrids had, on average, lower dynamic yield stability compared to the inbred lines. Grain yield performance of hybrids could be predicted based on midparent values and general combining ability (GCA)-predicted values. In contrast, stability variance of hybrids could be predicted only based on GCA-predicted values. We speculated that negative effects of the used CMS cytoplasm might be the reason for the low performance and yield stability of the hybrids. For this purpose a detailed study on the reasons for the drawback of the currently existing CMS system in triticale is urgently required comprising also the search of potentially alternative hybridization systems.
Dynamic Visualization of Co-expression in Systems Genetics Data

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

New, Joshua Ryan; Huang, Jian; Chesler, Elissa J

2008-01-01

Biologists hope to address grand scientific challenges by exploring the abundance of data made available through modern microarray technology and other high-throughput techniques. The impact of this data, however, is limited unless researchers can effectively assimilate such complex information and integrate it into their daily research; interactive visualization tools are called for to support the effort. Specifically, typical studies of gene co-expression require novel visualization tools that enable the dynamic formulation and fine-tuning of hypotheses to aid the process of evaluating sensitivity of key parameters. These tools should allow biologists to develop an intuitive understanding of the structure of biologicalmore » networks and discover genes which reside in critical positions in networks and pathways. By using a graph as a universal data representation of correlation in gene expression data, our novel visualization tool employs several techniques that when used in an integrated manner provide innovative analytical capabilities. Our tool for interacting with gene co-expression data integrates techniques such as: graph layout, qualitative subgraph extraction through a novel 2D user interface, quantitative subgraph extraction using graph-theoretic algorithms or by querying an optimized b-tree, dynamic level-of-detail graph abstraction, and template-based fuzzy classification using neural networks. We demonstrate our system using a real-world workflow from a large-scale, systems genetics study of mammalian gene co-expression.« less
Yield surfaces for frictional sphere assemblages

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

Goddard, J.D.; Didwania, A.K.

1995-12-31

By means of a recently developed computer algorithm for simulation of the quasi-static I mechanics of sphere assemblages, we have performed extensive computations of the dilatancy and plasticity of such systems for various proportional loading histories. We have investigated the effect of initial packing density or void ratio, size polydispersity, friction coefficient and plastic strain on the evolution of the yield surface. We find that all the yield surfaces tend to an asymptotic form which is well represented by the Lade-Duncan yield surface, developed originally for sand, suggesting that the Lade-Duncan form may reflect some universality in the behavior ofmore » assemblages of rigid frictional particles.« less
Increasing crop diversity mitigates weather variations and improves yield stability.

PubMed

Gaudin, Amélie C M; Tolhurst, Tor N; Ker, Alan P; Janovicek, Ken; Tortora, Cristina; Martin, Ralph C; Deen, William

2015-01-01

Cropping sequence diversification provides a systems approach to reduce yield variations and improve resilience to multiple environmental stresses. Yield advantages of more diverse crop rotations and their synergistic effects with reduced tillage are well documented, but few studies have quantified the impact of these management practices on yields and their stability when soil moisture is limiting or in excess. Using yield and weather data obtained from a 31-year long term rotation and tillage trial in Ontario, we tested whether crop rotation diversity is associated with greater yield stability when abnormal weather conditions occur. We used parametric and non-parametric approaches to quantify the impact of rotation diversity (monocrop, 2-crops, 3-crops without or with one or two legume cover crops) and tillage (conventional or reduced tillage) on yield probabilities and the benefits of crop diversity under different soil moisture and temperature scenarios. Although the magnitude of rotation benefits varied with crops, weather patterns and tillage, yield stability significantly increased when corn and soybean were integrated into more diverse rotations. Introducing small grains into short corn-soybean rotation was enough to provide substantial benefits on long-term soybean yields and their stability while the effects on corn were mostly associated with the temporal niche provided by small grains for underseeded red clover or alfalfa. Crop diversification strategies increased the probability of harnessing favorable growing conditions while decreasing the risk of crop failure. In hot and dry years, diversification of corn-soybean rotations and reduced tillage increased yield by 7% and 22% for corn and soybean respectively. Given the additional advantages associated with cropping system diversification, such a strategy provides a more comprehensive approach to lowering yield variability and improving the resilience of cropping systems to multiple environmental
Increasing Crop Diversity Mitigates Weather Variations and Improves Yield Stability

PubMed Central

Gaudin, Amélie C. M.; Tolhurst, Tor N.; Ker, Alan P.; Janovicek, Ken; Tortora, Cristina; Martin, Ralph C.; Deen, William

2015-01-01

Cropping sequence diversification provides a systems approach to reduce yield variations and improve resilience to multiple environmental stresses. Yield advantages of more diverse crop rotations and their synergistic effects with reduced tillage are well documented, but few studies have quantified the impact of these management practices on yields and their stability when soil moisture is limiting or in excess. Using yield and weather data obtained from a 31-year long term rotation and tillage trial in Ontario, we tested whether crop rotation diversity is associated with greater yield stability when abnormal weather conditions occur. We used parametric and non-parametric approaches to quantify the impact of rotation diversity (monocrop, 2-crops, 3-crops without or with one or two legume cover crops) and tillage (conventional or reduced tillage) on yield probabilities and the benefits of crop diversity under different soil moisture and temperature scenarios. Although the magnitude of rotation benefits varied with crops, weather patterns and tillage, yield stability significantly increased when corn and soybean were integrated into more diverse rotations. Introducing small grains into short corn-soybean rotation was enough to provide substantial benefits on long-term soybean yields and their stability while the effects on corn were mostly associated with the temporal niche provided by small grains for underseeded red clover or alfalfa. Crop diversification strategies increased the probability of harnessing favorable growing conditions while decreasing the risk of crop failure. In hot and dry years, diversification of corn-soybean rotations and reduced tillage increased yield by 7% and 22% for corn and soybean respectively. Given the additional advantages associated with cropping system diversification, such a strategy provides a more comprehensive approach to lowering yield variability and improving the resilience of cropping systems to multiple environmental
Loblolly Pine Growth and Yield Prediction for Managed West Gulf Plantations

Treesearch

V. Clark Baldwin; D.P. Feduccia

1987-01-01

Complete description, including tables, graphs, computer output, of a growth and yield prediction system providing volume and weight yields in stand and stock table format. An example of system use is given along with information about the computer program, COMPUTE P-LOB, that operates the system.
Signal Peptide and Denaturing Temperature are Critical Factors for Efficient Mammalian Expression and Immunoblotting of Cannabinoid Receptors*

PubMed Central

WANG, Chenyun; WANG, Yingying; WANG, Miao; CHEN, Jiankui; YU, Nong; SONG, Shiping; KAMINSKI, Norbert E.; ZHANG, Wei

2013-01-01

Summary Many researchers employed mammalian expression system to artificially express cannabinoid receptors, but immunoblot data that directly prove efficient protein expression can hardly be seen in related research reports. In present study, we demonstrated cannabinoid receptor protein was not able to be properly expressed with routine mammalian expression system. This inefficient expression was rescued by endowing an exogenous signal peptide ahead of cannabinoid receptor peptide. In addition, the artificially synthesized cannabinoid receptor was found to aggregate under routine sample denaturing temperatures (i.e., ≥95°C), forming a large molecular weight band when analyzed by immunoblotting. Only denaturing temperatures ≤75°C yielded a clear band at the predicted molecular weight. Collectively, we showed that efficient mammalian expression of cannabinoid receptors need a signal peptide sequence, and described the requirement for a low sample denaturing temperature in immunoblot analysis. These findings provide very useful information for efficient mammalian expression and immunoblotting of membrane receptors. PMID:22528237
MicroRNA profile of silk gland reveals different silk yields of three silkworm strains.

PubMed

Qin, Sheng; Danso, Blessing; Zhang, Jing; Li, Juan; Liu, Na; Sun, Xia; Hou, Chengxiang; Luo, Heng; Chen, Keping; Zhang, Guozheng; Li, Muwang

2018-05-05

Silk proteins are synthesized and secreted by the silk gland. The differential gene expression in it leads to different silk yield among various silkworm strains. As crucial factors, microRNAs (miRNAs) regulate protein synthesis at post-transcriptional level in silk gland. MiRNAs expression level in the silk gland of three silkworm strains (Jingsong, Lan10 and Dazao) was analyzed and 33 differentially expressed miRNAs (DEMs) were discovered between JingSong (JS) and Lan10 (L10), 60 DEMs between JS and Dazao, 54 DEMs between L10 and Dazao respectively. The DEMs target genes were predicted combing with two different methods and their functions were annotated according to gene ontology. Our previous studies showed that a batch of genes related to silk yield were identified in JS and L10 strains by comparative transcriptome and quantitative trait loci (QTL) method. Thirteen DEMs whose target genes are related to protein biosynthesis processes were screened by combining with these researches. Twelve DEMs potentially regulate nineteen genes which exist in our QTL results. Six common DEMs potentially regulate the genes in both of previous results. Finally, five DEMs were selected to verify their expression levels between JS and L10 by qRT-PCR, which showed similar difference as the results of small RNA-sequencing. MiRNAs in the silk gland may directly affect silk protein biosynthesis in different silkworm strains. In current work, we identified a batch of DEMs which potentially regulate the genes related to silk yield. Further functionally study of these miRNAs will contribute to improve varieties and boost the silk yield. Our research provides a basis for studying these miRNAs and their functions in silk production. Copyright © 2018 Elsevier B.V. All rights reserved.
Systemic bioinformatics analysis of skeletal muscle gene expression profiles of sepsis

PubMed Central

Yang, Fang; Wang, Yumei

2018-01-01

Sepsis is a type of systemic inflammatory response syndrome with high morbidity and mortality. Skeletal muscle dysfunction is one of the major complications of sepsis that may also influence the outcome of sepsis. The aim of the present study was to explore and identify potential mechanisms and therapeutic targets of sepsis. Systemic bioinformatics analysis of skeletal muscle gene expression profiles from the Gene Expression Omnibus was performed. Differentially expressed genes (DEGs) in samples from patients with sepsis and control samples were screened out using the limma package. Differential co-expression and coregulation (DCE and DCR, respectively) analysis was performed based on the Differential Co-expression Analysis package to identify differences in gene co-expression and coregulation patterns between the control and sepsis groups. Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways of DEGs were identified using the Database for Annotation, Visualization and Integrated Discovery, and inflammatory, cancer and skeletal muscle development-associated biological processes and pathways were identified. DCE and DCR analysis revealed several potential therapeutic targets for sepsis, including genes and transcription factors. The results of the present study may provide a basis for the development of novel therapeutic targets and treatment methods for sepsis. PMID:29805480
Effects of reduced nitrogen inputs on crop yield and nitrogen use efficiency in a long-term maize-soybean relay strip intercropping system.

PubMed

Chen, Ping; Du, Qing; Liu, Xiaoming; Zhou, Li; Hussain, Sajad; Lei, Lu; Song, Chun; Wang, Xiaochun; Liu, Weiguo; Yang, Feng; Shu, Kai; Liu, Jiang; Du, Junbo; Yang, Wenyu; Yong, Taiwen

2017-01-01

The blind pursuit of high yields via increased fertilizer inputs increases the environmental costs. Relay intercropping has advantages for yield, but a strategy for N management is urgently required to decrease N inputs without yield loss in maize-soybean relay intercropping systems (IMS). Experiments were conducted with three levels of N and three planting patterns, and dry matter accumulation, nitrogen uptake, nitrogen use efficiency (NUE), competition ratio (CR), system productivity index (SPI), land equivalent ratio (LER), and crop root distribution were investigated. Our results showed that the CR of soybean was greater than 1, and that the change in root distribution in space and time resulted in an interspecific facilitation in IMS. The maximum yield of maize under monoculture maize (MM) occurred with conventional nitrogen (CN), whereas under IMS, the maximum yield occurred with reduced nitrogen (RN). The yield of monoculture soybean (MS) and of soybean in IMS both reached a maximum under RN. The LER of IMS varied from 1.85 to 2.36, and the SPI peaked under RN. Additionally, the NUE of IMS increased by 103.7% under RN compared with that under CN. In conclusion, the separation of the root ecological niche contributed to a positive interspecific facilitation, which increased the land productivity. Thus, maize-soybean relay intercropping with reduced N input provides a very useful approach to increase land productivity and avert environmental pollution.
Endoribonuclease-Based Two-Component Repressor Systems for Tight Gene Expression Control in Plants

DOE PAGES

Liang, Yan; Richardson, Sarah; Yan, Jingwei; ...

2017-01-17

Tight control and multifactorial regulation of gene expression are important challenges in genetic engineering and are critical for the development of regulatory circuits. In meeting these challenges we will facilitate transgene expression regulation and support the fine-tuning of metabolic pathways to avoid the accumulation of undesired intermediates. By employing the endoribonuclease Csy4 and its recognition sequence from Pseudomonas aeruginosa and manipulating 5'UTR of mRNA, we developed a two-component expression–repression system to tightly control synthesis of transgene products. We demonstrated that this regulatory device was functional in monocotyledonous and dicotyledonous plant species, and showed that it can be used to repressmore » transgene expression by >400-fold and to synchronize transgene repression. In addition to tissue-specific transgene repression, this system offers stimuli-dependent expression control. Here, we identified 54 orthologous systems from various bacteria, using a bioinformatics approach and then validated in planta the activity for a few of those systems, demonstrating the potential diversity of such a two-component repressor system.« less
Endoribonuclease-Based Two-Component Repressor Systems for Tight Gene Expression Control in Plants

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

Liang, Yan; Richardson, Sarah; Yan, Jingwei

Tight control and multifactorial regulation of gene expression are important challenges in genetic engineering and are critical for the development of regulatory circuits. In meeting these challenges we will facilitate transgene expression regulation and support the fine-tuning of metabolic pathways to avoid the accumulation of undesired intermediates. By employing the endoribonuclease Csy4 and its recognition sequence from Pseudomonas aeruginosa and manipulating 5'UTR of mRNA, we developed a two-component expression–repression system to tightly control synthesis of transgene products. We demonstrated that this regulatory device was functional in monocotyledonous and dicotyledonous plant species, and showed that it can be used to repressmore » transgene expression by >400-fold and to synchronize transgene repression. In addition to tissue-specific transgene repression, this system offers stimuli-dependent expression control. Here, we identified 54 orthologous systems from various bacteria, using a bioinformatics approach and then validated in planta the activity for a few of those systems, demonstrating the potential diversity of such a two-component repressor system.« less
Plant development and yield of four sugarcane varieties irrigated by a subsurface drip irrigation system in Campinas, Brazil

NASA Astrophysics Data System (ADS)

Silva, André Luiz Barros de O.; Célia de Matos Pires, Regina; Yukitaka Pessinati Ohashi, Augusto; Vasconcelos Ribeiro, Rafael; Landell, Marcos Guimarães de Andrade; Aparecida Creste Dias de Souza, Silvana

2013-04-01

The biofuel production is a growing concern on modern society due to the agricultural sustainability, in which both food and energy supply should be taken into account. The agroclimatic zoning indicates that sugarcane expansion in Brazil can only take place in marginal lands, where water deficit occurs and irrigation is necessary. The use of subsurface drip irrigation (SDI) in sugarcane cultivation is an interesting cultural practice to improve production and allow cultivation in marginal lands due to water deficit conditions or to attain high yield and to increase longevity of plants. In this context it is necessary to investigate responses of different varieties to water supply. The aim of this work was to evaluate the plant development and yield of four sugarcane varieties irrigated by a subsurface drip irrigation system in Campinas, Brazil in the 1st cane ratoon cycle. The field experiment was carried out in Campinas SP Brazil, with IACSP95-5000, IACSP94-2094, IACSP94-2101 and SP79-1011 cultivars in the 1st cane ratoon cycle, from January (after the harvest of cane plant cycle) to October (harvest the 1st cane ratoon cycle). The plant spacing was 1.5 m between rows. Each cultivar was planted in an area of 0.4 hectares. The irrigation was done by a subsuperficial drip system with one drip line in each plant row installed at 0.25 m deep. During the 1st cane ratoon cycle the parameters were analysed on the 33rd, 123rd, 185th and 277th day. The analysed parameters were: plant yield (m), leaf area index (LAI) and yield (tons per hectare). According to the results from the second sampling (123rd day) the varieties IACSP95-5000 and IACSP94-2101 showed higher plant height when compared to the other varieties. However, from the third sampling (185th day) on the IACSP95-5000 variety grew considerably taller than the other varieties. The varieties SP79-1011and IACSP94-2101 presented lower values of LAI throughout the crop cycle when compared to other varieties. But on the
Increased phytochrome B alleviates density effects on tuber yield of field potato crops.

PubMed

Boccalandro, Hernán E; Ploschuk, Edmundo L; Yanovsky, Marcelo J; Sánchez, Rodolfo A; Gatz, Christiane; Casal, Jorge J

2003-12-01

The possibility that reduced photomorphogenic responses could increase field crop yield has been suggested often, but experimental support is still lacking. Here, we report that ectopic expression of the Arabidopsis PHYB (phytochrome B) gene, a photoreceptor involved in detecting red to far-red light ratio associated with plant density, can increase tuber yield in field-grown transgenic potato (Solanum tuberosum) crops. Surprisingly, this effect was larger at very high densities, despite the intense reduction in the red to far-red light ratios and the concomitant narrowed differences in active phytochrome B levels between wild type and transgenics at these densities. Increased PHYB expression not only altered the ability of plants to respond to light signals, but they also modified the light environment itself. This combination resulted in larger effects of enhanced PHYB expression on tuber number and crop photosynthesis at high planting densities. The PHYB transgenics showed higher maximum photosynthesis in leaves of all strata of the canopy, and this effect was largely due to increased leaf stomatal conductance. We propose that enhanced PHYB expression could be used in breeding programs to shift optimum planting densities to higher levels.
Whole blood transcriptional profiling comparison between different milk yield of Chinese Holstein cows using RNA-seq data.

PubMed

Bai, Xue; Zheng, Zhuqing; Liu, Bin; Ji, Xiaoyang; Bai, Yongsheng; Zhang, Wenguang

2016-08-22

The objective of this research was to investigate the variation of gene expression in the blood transcriptome profile of Chinese Holstein cows associated to the milk yield traits. We used RNA-seq to generate the bovine transcriptome from the blood of 23 lactating Chinese Holstein cows with extremely high and low milk yield. A total of 100 differentially expressed genes (DEGs) (p < 0.05, FDR < 0.05) were revealed between the high and low groups. Gene ontology (GO) analysis demonstrated that the 100 DEGs were enriched in specific biological processes with regard to defense response, immune response, inflammatory response, icosanoid metabolic process, and fatty acid metabolic process (p < 0.05). The KEGG pathway analysis with 100 DEGs revealed that the most statistically-significant metabolic pathway was related with Toll-like receptor signaling pathway (p < 0.05). The expression level of four selected DEGs was analyzed by qRT-PCR, and the results indicated that the expression patterns were consistent with the deep sequencing results by RNA-Seq. Furthermore, alternative splicing analysis of 100 DEGs demonstrated that there were different splicing pattern between high and low yielders. The alternative 3' splicing site was the major splicing pattern detected in high yielders. However, in low yielders the major type was exon skipping. This study provides a non-invasive method to identify the DEGs in cattle blood using RNA-seq for milk yield. The revealed 100 DEGs between Holstein cows with extremely high and low milk yield, and immunological pathway are likely involved in milk yield trait. Finally, this study allowed us to explore associations between immune traits and production traits related to milk production.
Integrated analysis of phenome, genome, and transcriptome of hybrid rice uncovered multiple heterosis-related loci for yield increase

PubMed Central

Li, Dayong; Huang, Zhiyuan; Song, Shuhui; Xin, Yeyun; Mao, Donghai; Lv, Qiming; Zhou, Ming; Tian, Dongmei; Tang, Mingfeng; Wu, Qi; Liu, Xue; Chen, Tingting; Song, Xianwei; Fu, Xiqin; Zhao, Bingran; Liang, Chengzhi; Li, Aihong; Liu, Guozhen; Li, Shigui; Hu, Songnian; Cao, Xiaofeng; Yu, Jun; Yuan, Longping; Chen, Caiyan; Zhu, Lihuang

2016-01-01

Hybrid rice is the dominant form of rice planted in China, and its use has extended worldwide since the 1970s. It offers great yield advantages and has contributed greatly to the world’s food security. However, the molecular mechanisms underlying heterosis have remained a mystery. In this study we integrated genetics and omics analyses to determine the candidate genes for yield heterosis in a model two-line rice hybrid system, Liang-you-pei 9 (LYP9) and its parents. Phenomics study revealed that the better parent heterosis (BPH) of yield in hybrid is not ascribed to BPH of all the yield components but is specific to the BPH of spikelet number per panicle (SPP) and paternal parent heterosis (PPH) of effective panicle number (EPN). Genetic analyses then identified multiple quantitative trait loci (QTLs) for these two components. Moreover, a number of differentially expressed genes and alleles in the hybrid were mapped by transcriptome profiling to the QTL regions as possible candidate genes. In parallel, a major QTL for yield heterosis, rice heterosis 8 (RH8), was found to be the DTH8/Ghd8/LHD1 gene. Based on the shared allelic heterozygosity of RH8 in many hybrid rice cultivars, a common mechanism for yield heterosis in the present commercial hybrid rice is proposed. PMID:27663737

Enhanced Gene Expression Rather than Natural Polymorphism in Coding Sequence of the OsbZIP23 Determines Drought Tolerance and Yield Improvement in Rice Genotypes

PubMed Central

Dey, Avishek; Samanta, Milan Kumar; Gayen, Srimonta; Sen, Soumitra K.; Maiti, Mrinal K.

2016-01-01

Drought is one of the major limiting factors for productivity of crops including rice (Oryza sativa L.). Understanding the role of allelic variations of key regulatory genes involved in stress-tolerance is essential for developing an effective strategy to combat drought. The bZIP transcription factors play a crucial role in abiotic-stress adaptation in plants via abscisic acid (ABA) signaling pathway. The present study aimed to search for allelic polymorphism in the OsbZIP23 gene across selected drought-tolerant and drought-sensitive rice genotypes, and to characterize the new allele through overexpression (OE) and gene-silencing (RNAi). Analyses of the coding DNA sequence (CDS) of the cloned OsbZIP23 gene revealed single nucleotide polymorphism at four places and a 15-nucleotide deletion at one place. The single-copy OsbZIP23 gene is expressed at relatively higher level in leaf tissues of drought-tolerant genotypes, and its abundance is more in reproductive stage. Cloning and sequence analyses of the OsbZIP23-promoter from drought-tolerant O. rufipogon and drought-sensitive IR20 cultivar showed variation in the number of stress-responsive cis-elements and a 35-nucleotide deletion at 5’-UTR in IR20. Analysis of the GFP reporter gene function revealed that the promoter activity of O. rufipogon is comparatively higher than that of IR20. The overexpression of any of the two polymorphic forms (1083 bp and 1068 bp CDS) of OsbZIP23 improved drought tolerance and yield-related traits significantly by retaining higher content of cellular water, soluble sugar and proline; and exhibited decrease in membrane lipid peroxidation in comparison to RNAi lines and non-transgenic plants. The OE lines showed higher expression of target genes-OsRab16B, OsRab21 and OsLEA3-1 and increased ABA sensitivity; indicating that OsbZIP23 is a positive transcriptional-regulator of the ABA-signaling pathway. Taken together, the present study concludes that the enhanced gene expression rather
Orbital express capture system: concept to reality

NASA Astrophysics Data System (ADS)

Stamm, Shane; Motaghedi, Pejmun

2004-08-01

The development of autonomous servicing of on-orbit spacecraft has been a sought after objective for many years. A critical component of on-orbit servicing involves the ability to successfully capture, institute mate, and perform electrical and fluid transfers autonomously. As part of a Small Business Innovation Research (SBIR) grant, Starsys Research Corporation (SRC) began developing such a system. Phase I of the grant started in 1999, with initial work focusing on simultaneously defining the parameters associated with successful docking while designing to those parameters. Despite the challenge of working without specific requirements, SRC completed development of a prototype design in 2000. Throughout the following year, testing was conducted on the prototype to characterize its performance. Having successfully completed work on the prototype, SRC began a Phase II SBIR effort in mid-2001. The focus of the second phase was a commercialization effort designed to augment the prototype model into a more flight-like design. The technical requirements, however, still needed clear definition for the design to progress. The advent of the Orbital Express (OE) program provided much of that definition. While still in the proposal stages of the OE program, SRC began tailoring prototype redesign efforts to the OE program requirements. A primary challenge involved striking a balance between addressing the technical requirements of OE while designing within the scope of the SBIR. Upon award of the OE contract, the Phase II SBIR design has been fully developed. This new design, designated the Mechanical Docking System (MDS), successfully incorporated many of the requirements of the OE program. SRC is now completing dynamic testing on the MDS hardware, with a parallel effort of developing a flight design for OE. As testing on the MDS progresses, the design path that was once common to both SBIR effort and the OE program begins to diverge. The MDS will complete the scope of the
Differential expression of neuroligin genes in the nervous system of zebrafish.

PubMed

Davey, Crystal; Tallafuss, Alexandra; Washbourne, Philip

2010-02-01

The establishment and maturation of appropriate synaptic connections is crucial in the development of neuronal circuits. Cellular adhesion is believed to play a central role in this process. Neuroligins are neuronal cell adhesion molecules that are hypothesized to act in the initial formation and maturation of synaptic connections. In order to establish the zebrafish as a model to investigate the in vivo role of Neuroligin proteins in nervous system development, we identified the zebrafish orthologs of neuroligin family members and characterized their expression. Zebrafish possess seven neuroligin genes. Synteny analysis and sequence comparisons show that NLGN2, NLGN3, and NLGN4X are duplicated in zebrafish, but NLGN1 has a single zebrafish ortholog. All seven zebrafish neuroligins are expressed in complex patterns in the developing nervous system and in the adult brain. The spatial and temporal expression patterns of these genes suggest that they occupy a role in nervous system development and maintenance.
Contribution of morphoagronomic traits to grain yield and earliness in grain sorghum.

PubMed

da Silva, K J; Teodoro, P E; de Menezes, C B; Júlio, M P M; de Souza, V F; da Silva, M J; Pimentel, L D; Borém, A

2017-05-04

Given the importance of selecting lines to obtain hybrids, we aimed to verify the relationship between morphological traits that can be used as the criteria for the selection of sorghum lines with high grain yield and earliness. A total of 18 traits were evaluated in 160 sorghum elite lines, in an incomplete block design with two replicates. A correlation network was used to graphically express the estimates of phenotypic and genotypic correlations between the traits. Two path analyses were processed, the first considering grain yield and the second considering flowering as the principle dependent variable. In general, most of the variation in the grain yield and flowering of sorghum lines was explained by the traits evaluated. Selecting sorghum lines with greater width of the third leaf blade from flag leaf, panicle weight, and panicle harvest index might lead to increased grain yield, and selecting sorghum genotypes with higher plant height might lead to reduced earliness and increased grain yield. Thus, the results suggest the establishment of selection indices aiming at simultaneously increasing the grain yield and earliness in sorghum genotypes.
[Progress in expression and molecular modification of microbial transglutaminase].

PubMed

Liu, Song; Zhang, Dongxu; Du, Guocheng; Chen, Jian

2011-12-01

Microbial transglutaminase, which could catalyze the cross-linking of many proteins or non-protein materials, has been widely used in food, pharmaceutical and textile industry. To enhance the yield of the enzyme and establish corresponding platform for molecular modification, the researchers of Japanese Ajinomoto began to construct the recombinant strain producing transglutaminase in the 1990s. So far, the enzyme has been successfully expressed in different expression systems. Some of the recombinant strains are more productive than wild strains. Recently, progress has been made in the molecular modification of microbial transglutaminase, and the activity, thermo-stability and specificity of the enzyme are improved. This review briefly summarized and analyzed the strategies involved in these studies, and noted its trends.
Expression of adhA from different organisms in Clostridium thermocellum.

PubMed

Zheng, Tianyong; Cui, Jingxuan; Bae, Hye Ri; Lynd, Lee R; Olson, Daniel G

2017-01-01

Clostridium thermocellum is a cellulolytic anaerobic thermophile that is a promising candidate for consolidated bioprocessing of lignocellulosic biomass into biofuels such as ethanol. It was previously shown that expressing Thermoanaerobacterium saccharolyticum adhA in C. thermocellum increases ethanol yield.In this study, we investigated expression of adhA genes from different organisms in Clostridium thermocellum . Based on sequence identity to T. saccharolyticum adhA , we chose adhA genes from 10 other organisms: Clostridium botulinum , Methanocaldococcus bathoardescens , Thermoanaerobacterium ethanolicus , Thermoanaerobacter mathranii , Thermococcus strain AN1, Thermoanaerobacterium thermosaccharolyticum , Caldicellulosiruptor saccharolyticus , Fervidobacterium nodosum , Marinitoga piezophila , and Thermotoga petrophila . All 11 adhA genes (including T. saccharolyticum adhA ) were expressed in C. thermocellum and fermentation end products were analyzed. All 11 adhA genes increased C. thermocellum ethanol yield compared to the empty-vector control. C. botulinum and T. ethanolicus adhA genes generated significantly higher ethanol yield than T. saccharolyticum adhA . Our results indicated that expressing adhA is an effective method of increasing ethanol yield in wild-type C. thermocellum , and that this appears to be a general property of adhA genes.
Co-expression of interleukin 12 enhances antitumor effects of a novel chimeric promoter-mediated suicide gene therapy in an immunocompetent mouse model

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

Xu, Yu, E-mail: xuyu1001@gmail.com; Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, 169 Donghu Road, Wuhan 430071; Liu, Zhengchun, E-mail: l135027@126.com

Highlights: {yields} A novel chimeric promoter consisting of CArG element and hTERT promoter was developed. {yields} The promoter was characterized with radiation-inducibility and tumor-specificity. {yields} Suicide gene system driven by the promoter showed remarkable cytotoxicity in vitro. {yields} Co-expression of IL12 enhanced the promoter mediated suicide gene therapy in vivo. -- Abstract: The human telomerase reverse transcriptase (hTERT) promoter has been widely used in target gene therapy of cancer. However, low transcriptional activity limited its clinical application. Here, we designed a novel dual radiation-inducible and tumor-specific promoter system consisting of CArG elements and the hTERT promoter, resulting in increased expressionmore » of reporter genes after gamma-irradiation. Therapeutic and side effects of adenovirus-mediated horseradish peroxidase (HRP)/indole-3-acetic (IAA) system downstream of the chimeric promoter were evaluated in mice bearing Lewis lung carcinoma, combining with or without adenovirus-mediated interleukin 12 (IL12) gene driven by the cytomegalovirus promoter. The combination treatment showed more effective suppression of tumor growth than those with single agent alone, being associated with pronounced intratumoral T-lymphocyte infiltration and minor side effects. Our results suggest that the combination treatment with HRP/IAA system driven by the novel chimeric promoter and the co-expression of IL12 might be an effective and safe target gene therapy strategy of cancer.« less
Dependency of global primary bioenergy crop potentials in 2050 on food systems, yields, biodiversity conservation and political stability.

PubMed

Erb, Karl-Heinz; Haberl, Helmut; Plutzar, Christoph

2012-08-01

The future bioenergy crop potential depends on (1) changes in the food system (food demand, agricultural technology), (2) political stability and investment security, (3) biodiversity conservation, (4) avoidance of long carbon payback times from deforestation, and (5) energy crop yields. Using a biophysical biomass-balance model, we analyze how these factors affect global primary bioenergy potentials in 2050. The model calculates biomass supply and demand balances for eleven world regions, eleven food categories, seven food crop types and two livestock categories, integrating agricultural forecasts and scenarios with a consistent global land use and NPP database. The TREND scenario results in a global primary bioenergy potential of 77 EJ/yr, alternative assumptions on food-system changes result in a range of 26-141 EJ/yr. Exclusion of areas for biodiversity conservation and inaccessible land in failed states reduces the bioenergy potential by up to 45%. Optimistic assumptions on future energy crop yields increase the potential by up to 48%, while pessimistic assumptions lower the potential by 26%. We conclude that the design of sustainable bioenergy crop production policies needs to resolve difficult trade-offs such as food vs. energy supply, renewable energy vs. biodiversity conservation or yield growth vs. reduction of environmental problems of intensive agriculture.
Dependency of global primary bioenergy crop potentials in 2050 on food systems, yields, biodiversity conservation and political stability

PubMed Central

Erb, Karl-Heinz; Haberl, Helmut; Plutzar, Christoph

2012-01-01

The future bioenergy crop potential depends on (1) changes in the food system (food demand, agricultural technology), (2) political stability and investment security, (3) biodiversity conservation, (4) avoidance of long carbon payback times from deforestation, and (5) energy crop yields. Using a biophysical biomass-balance model, we analyze how these factors affect global primary bioenergy potentials in 2050. The model calculates biomass supply and demand balances for eleven world regions, eleven food categories, seven food crop types and two livestock categories, integrating agricultural forecasts and scenarios with a consistent global land use and NPP database. The TREND scenario results in a global primary bioenergy potential of 77 EJ/yr, alternative assumptions on food-system changes result in a range of 26–141 EJ/yr. Exclusion of areas for biodiversity conservation and inaccessible land in failed states reduces the bioenergy potential by up to 45%. Optimistic assumptions on future energy crop yields increase the potential by up to 48%, while pessimistic assumptions lower the potential by 26%. We conclude that the design of sustainable bioenergy crop production policies needs to resolve difficult trade-offs such as food vs. energy supply, renewable energy vs. biodiversity conservation or yield growth vs. reduction of environmental problems of intensive agriculture. PMID:23576836
Local yield stress statistics in model amorphous solids

NASA Astrophysics Data System (ADS)

Barbot, Armand; Lerbinger, Matthias; Hernandez-Garcia, Anier; García-García, Reinaldo; Falk, Michael L.; Vandembroucq, Damien; Patinet, Sylvain

2018-03-01

We develop and extend a method presented by Patinet, Vandembroucq, and Falk [Phys. Rev. Lett. 117, 045501 (2016), 10.1103/PhysRevLett.117.045501] to compute the local yield stresses at the atomic scale in model two-dimensional Lennard-Jones glasses produced via differing quench protocols. This technique allows us to sample the plastic rearrangements in a nonperturbative manner for different loading directions on a well-controlled length scale. Plastic activity upon shearing correlates strongly with the locations of low yield stresses in the quenched states. This correlation is higher in more structurally relaxed systems. The distribution of local yield stresses is also shown to strongly depend on the quench protocol: the more relaxed the glass, the higher the local plastic thresholds. Analysis of the magnitude of local plastic relaxations reveals that stress drops follow exponential distributions, justifying the hypothesis of an average characteristic amplitude often conjectured in mesoscopic or continuum models. The amplitude of the local plastic rearrangements increases on average with the yield stress, regardless of the system preparation. The local yield stress varies with the shear orientation tested and strongly correlates with the plastic rearrangement locations when the system is sheared correspondingly. It is thus argued that plastic rearrangements are the consequence of shear transformation zones encoded in the glass structure that possess weak slip planes along different orientations. Finally, we justify the length scale employed in this work and extract the yield threshold statistics as a function of the size of the probing zones. This method makes it possible to derive physically grounded models of plasticity for amorphous materials by directly revealing the relevant details of the shear transformation zones that mediate this process.
ADAM15 expression is downregulated in melanoma metastasis compared to primary melanoma

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

Ungerer, Christopher; Doberstein, Kai; Buerger, Claudia

2010-10-22

Research highlights: {yields} Strong ADAM15 expression is found in normal melanocytes. {yields} ADAM15 expression is significantly downregulated in patients with melanoma metastasis. {yields} TGF-{beta} can downregulate ADAM15 expression in melanoma cells. {yields} Overexpression of ADAM15 in melanoma cells inhibits migration, proliferation and invasion of melanoma cells. {yields} Conclusion: ADAM15 represents an tumor suppressor protein in melanoma. -- Abstract: In a mouse melanoma metastasis model it has been recently shown that ADAM15 overexpression in melanoma cells significantly reduced the number of metastatic nodules on the lung. Unfortunately, the expression of ADAM15 in human melanoma tissue has not been determined so far.more » In our study, we characterized the expression of ADAM15 in tissue micro-arrays of patients with primary melanoma with melanoma metastasis. ADAM15 was expressed in melanocytes and endothelial cells of benign nevi and melanoma tissue. Importantly, ADAM15 was significantly downregulated in melanoma metastasis compared to primary melanoma. We further demonstrate that IFN-{gamma} and TGF-{beta} downregulate ADAM15 protein levels in melanoma cells. To investigate the role of ADAM15 in melanoma progression, we overexpressed ADAM15 in melanoma cells. Importantly, overexpression of ADAM15 in melanoma cells reduced the migration, invasion and the anchorage dependent and independent cell growth of melanoma cells. In summary, the downregulation of ADAM15 plays an important role in melanoma progression and ADAM15 act as a tumorsuppressor in melanoma.« less
Optimization of a nonviral transfection system to evaluate Cox-2 controlled interleukin-4 expression for osteoarthritis gene therapy in vitro.

PubMed

Lang, Annemarie; Neuhaus, Johannes; Pfeiffenberger, Moritz; Schröder, Erik; Ponomarev, Igor; Weber, Yvonne; Gaber, Timo; Schmidt, Michael F G

2014-01-01

Gene therapy appears to have the potential for achieving a long-term remedy for osteoarthritis (OA). However, there is a risk of adverse reactions, especially when using cytomegalovirus-controlled expression. To provide a safe application, we focused on the expression of therapeutic cytokines [e.g. interleukin (IL)-4] in a disease-responsive manner by use of the previously cloned Cox-2 promoter as 'genetic switch'. In the present study, we report the functionality of a controlled gene therapeutic system in an equine osteoarthritic cell model. Different nonviral transfection reagents were tested for their efficiency on equine chondrocytes stimulated with equine IL-1β or lipopolysaccharide to create an inflammatory environment. To optimize the transfection, we successfully redesigned the vector by excluding the internal ribosomal entry site (IRES). The functionality of our Cox-2 promoter construct with respect to expressing IL-4 was proven at the mRNA and protein levels and the anti-inflammatory potential of IL-4 was confirmed by analyzing the expression of IL-1β, IL-6, IL-8, matrix metalloproteinase (MMP)-1, MMP-3 and tumor necrosis factor (TNF)-α using a quantitative polymerase chain reaction. Nonviral transfection reagents yielded transfection rates from 21% to 44% with control vectors with and without IRES, respectively. Stimulation of equine chondrocytes resulted in a 20-fold increase of mRNA expression of IL-1β. Such exogenous stimulation of chondrocytes transfected with pNCox2-IL4 led to an increase of IL-4 mRNA expression, whereas expression of inflammatory mediators decreased. The timely link between these events confirms the anti-inflammatory potential of synthesized IL-4. We consider that this approach has significant potential for translation into a useful anti-inflammation therapy. Molecular tools such as the described therapeutic plasmid pave the way for a local-controlled, self-limiting gene therapy. Copyright © 2014 John Wiley & Sons, Ltd.
High yield bacterial expression, purification and characterisation of bioactive Human Tousled-like Kinase 1B involved in cancer.

PubMed

Bhoir, Siddhant; Shaik, Althaf; Thiruvenkatam, Vijay; Kirubakaran, Sivapriya

2018-03-19

Human Tousled-like kinases (TLKs) are highly conserved serine/threonine protein kinases responsible for cell proliferation, DNA repair, and genome surveillance. Their possible involvement in cancer via efficient DNA repair mechanisms have made them clinically relevant molecular targets for anticancer therapy. Innovative approaches in chemical biology have played a key role in validating the importance of kinases as molecular targets. However, the detailed understanding of the protein structure and the mechanisms of protein-drug interaction through biochemical and biophysical techniques demands a method for the production of an active protein of exceptional stability and purity on a large scale. We have designed a bacterial expression system to express and purify biologically active, wild-type Human Tousled-like Kinase 1B (hTLK1B) by co-expression with the protein phosphatase from bacteriophage λ. We have obtained remarkably high amounts of the soluble and homogeneously dephosphorylated form of biologically active hTLK1B with our unique, custom-built vector design strategy. The recombinant hTLK1B can be used for the structural studies and may further facilitate the development of new TLK inhibitors for anti-cancer therapy using a structure-based drug design approach.
Validation of the Unthinned Loblolly Pine Plantation Yield Model-USLYCOWG

Treesearch

V. Clark Baldwin; D.P. Feduccia

1982-01-01

Yield and stand structure predictions from an unthinned loblolly pine plantation yield prediction system (USLYCOWG computer program) were compared with observations from 80 unthinned loblolly pine plots. Overall, the predicted estimates were reasonable when compared to observed values, but predictions based on input data at or near the system's limits may be in...
Three-dimensional spheroid culture of human umbilical cord mesenchymal stem cells promotes cell yield and stemness maintenance.

PubMed

Li, Yi; Guo, Gang; Li, Li; Chen, Fei; Bao, Ji; Shi, Yu-Jun; Bu, Hong

2015-05-01

Mesenchymal stem cell (MSC) transplantation is a promising treatment of many diseases. However, conventional techniques with cells being cultured as a monolayer result in slow cell proliferation and insufficient yield to meet clinical demands. Three-dimensional (3D) culture systems are gaining attention with regard to recreating a complex microenvironment and to understanding the conditions experienced by cells. Our aim is to establish a novel 3D system for the culture of human umbilical cord MSCs (hUC-MSCs) within a real 3D microenvironment but with no digestion or passaging. Primary hUC-MSCs were isolated and grown in serum-free medium (SFM) on a suspension Rocker system. Cell characteristics including proliferation, phenotype and multipotency were recorded. The therapeutic effects of 3D-cultured hUC-MSCs on carbon tetrachloride (CCl4)-induced acute liver failure in mouse models were examined. In the 3D Rocker system, hUC-MSCs formed spheroids in SFM and maintained high viability and active proliferation. Compared with monolayer culture, the 3D-culture system yielded more hUC-MSCs cells within the same volume. The spheroids expressed higher levels of stem cell markers and displayed stronger multipotency. After transplantation into mouse, 3D hUC-MSCs significantly promoted the secretion of interferon-γ and interleukin-6 but inhibited that of tumor necrosis factor-α, thereby alleviating liver necrosis and promoting regeneration following CCl4 injury. The 3D culture of hUC-MSCs thus promotes cell yield and stemness maintenance and represents a promising strategy for hUC-MSCs expansion on an industrial scale with great potential for cell therapy and biotechnology.
A Priori Estimation of Organic Reaction Yields

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

Emami, Fateme S.; Vahid, Amir; Wylie, Elizabeth K.

2015-07-21

A thermodynamically guided calculation of free energies of substrate and product molecules allows for the estimation of the yields of organic reactions. The non-ideality of the system and the solvent effects are taken into account through the activity coefficients calculated at the molecular level by perturbed-chain statistical associating fluid theory (PC-SAFT). The model is iteratively trained using a diverse set of reactions with yields that have been reported previously. This trained model can then estimate a priori the yields of reactions not included in the training set with an accuracy of ca. ±15 %. This ability has the potential tomore » translate into significant economic savings through the selection and then execution of only those reactions that can proceed in good yields.« less
Engineering of a green-light inducible gene expression system in Synechocystis sp. PCC6803.

PubMed

Abe, Koichi; Miyake, Kotone; Nakamura, Mayumi; Kojima, Katsuhiro; Ferri, Stefano; Ikebukuro, Kazunori; Sode, Koji

2014-03-01

In order to construct a green-light-regulated gene expression system for cyanobacteria, we characterized a green-light sensing system derived from Synechocystis sp. PCC6803, consisting of the green-light sensing histidine kinase CcaS, the cognate response regulator CcaR, and the promoter of cpcG2 (PcpcG 2 ). CcaS and CcaR act as a genetic controller and activate gene expression from PcpcG 2 with green-light illumination. The green-light induction level of the native PcpcG 2 was investigated using GFPuv as a reporter gene inserted in a broad-host-range vector. A clear induction of protein expression from native PcpcG 2 under green-light illumination was observed; however, the expression level was very low compared with Ptrc , which was reported to act as a constitutive promoter in cyanobacteria. Therefore, a Shine-Dalgarno-like sequence derived from the cpcB gene was inserted in the 5' untranslated region of the cpcG2 gene, and the expression level of CcaR was increased. Thus, constructed engineered green-light sensing system resulted in about 40-fold higher protein expression than with the wild-type promoter with a high ON/OFF ratio under green-light illumination. The engineered green-light gene expression system would be a useful genetic tool for controlling gene expression in the emergent cyanobacterial bioprocesses. © 2013 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.
Analysis of a Plant Transcriptional Regulatory Network Using Transient Expression Systems.

PubMed

Díaz-Triviño, Sara; Long, Yuchen; Scheres, Ben; Blilou, Ikram

2017-01-01

In plant biology, transient expression systems have become valuable approaches used routinely to rapidly study protein expression, subcellular localization, protein-protein interactions, and transcriptional activity prior to in vivo studies. When studying transcriptional regulation, luciferase reporter assays offer a sensitive readout for assaying promoter behavior in response to different regulators or environmental contexts and to confirm and assess the functional relevance of predicted binding sites in target promoters. This chapter aims to provide detailed methods for using luciferase reporter system as a rapid, efficient, and versatile assay to analyze transcriptional regulation of target genes by transcriptional regulators. We describe a series of optimized transient expression systems consisting of Arabidopsis thaliana protoplasts, infiltrated Nicotiana benthamiana leaves, and human HeLa cells to study the transcriptional regulations of two well-characterized transcriptional regulators SCARECROW (SCR) and SHORT-ROOT (SHR) on one of their targets, CYCLIN D6 (CYCD6).Here, we illustrate similarities and differences in outcomes when using different systems. The plant-based systems revealed that the SCR-SHR complex enhances CYCD6 transcription, while analysis in HeLa cells showed that the complex is not sufficient to strongly induce CYCD6 transcription, suggesting that additional, plant-specific regulators are required for full activation. These results highlight the importance of the system and suggest that including heterologous systems, such as HeLa cells, can provide a more comprehensive analysis of a complex gene regulatory network.
Expression of cyanobacterial FBP/SBPase in soybean prevents yield depression under future climate conditions

USDA-ARS?s Scientific Manuscript database

Predictions suggest that current crop production needs to double by 2050 to meet global food and energy demands. Based on theory and experimental studies, overexpression of the photosynthetic enzyme sedoheptulose-1,7-bisphosphatase (SBPase) is expected to enhance C3 crop photosynthesis and yields. H...
High-yield soluble expression, purification and characterization of human steroidogenic acute regulatory protein (StAR) fused to a cleavable Maltose-Binding Protein (MBP).

PubMed

Sluchanko, Nikolai N; Tugaeva, Kristina V; Faletrov, Yaroslav V; Levitsky, Dmitrii I

2016-03-01

Steroidogenic acute regulatory protein (StAR) is responsible for the rapid delivery of cholesterol to mitochondria where the lipid serves as a source for steroid hormones biosynthesis in adrenals and gonads. Despite many successful investigations, current understanding of the mechanism of StAR action is far from being completely clear. StAR was mostly obtained using denaturation/renaturation or in minor quantities in a soluble form at decreased temperatures that, presumably, limited the possibilities for its consequent detailed exploration. In our hands, existing StAR expression constructs could be bacterially expressed almost exclusively as insoluble forms, even upon decreased expression temperatures and in specific strains of Escherichia coli, and isolated protein tended to aggregate and was difficult to handle. To maximize the yield of soluble protein, optimized StAR sequence encompassing functional domain STARD1 (residues 66-285) was fused to the C-terminus of His-tagged Maltose-Binding Protein (MBP) with the possibility to cleave off the whole tag by 3C protease. The developed protocol of expression and purification comprising of a combination of subtractive immobilized metal affinity chromatography (IMAC) and size-exclusion chromatography allowed us to obtain up to 25 mg/1 L culture of completely soluble StAR protein, which was (i) homogenous according to SDS-PAGE, (ii) gave a single symmetrical peak on a gel-filtration, (iii) showed the characteristic CD spectrum and (iv) pH-dependent ability to bind a fluorescently-labeled cholesterol analogue. We conclude that our strategy provides fully soluble and native StAR protein which in future could be efficiently used for biotechnology and drug discovery aimed at modulation of steroids production. Copyright © 2015 Elsevier Inc. All rights reserved.

Assimilating Remote Sensing Observations of Leaf Area Index and Soil Moisture for Wheat Yield Estimates: An Observing System Simulation Experiment

NASA Technical Reports Server (NTRS)

Nearing, Grey S.; Crow, Wade T.; Thorp, Kelly R.; Moran, Mary S.; Reichle, Rolf H.; Gupta, Hoshin V.

2012-01-01

Observing system simulation experiments were used to investigate ensemble Bayesian state updating data assimilation of observations of leaf area index (LAI) and soil moisture (theta) for the purpose of improving single-season wheat yield estimates with the Decision Support System for Agrotechnology Transfer (DSSAT) CropSim-Ceres model. Assimilation was conducted in an energy-limited environment and a water-limited environment. Modeling uncertainty was prescribed to weather inputs, soil parameters and initial conditions, and cultivar parameters and through perturbations to model state transition equations. The ensemble Kalman filter and the sequential importance resampling filter were tested for the ability to attenuate effects of these types of uncertainty on yield estimates. LAI and theta observations were synthesized according to characteristics of existing remote sensing data, and effects of observation error were tested. Results indicate that the potential for assimilation to improve end-of-season yield estimates is low. Limitations are due to a lack of root zone soil moisture information, error in LAI observations, and a lack of correlation between leaf and grain growth.
Candidate innate immune system gene expression in the ecological model Daphnia

PubMed Central

Decaestecker, Ellen; Labbé, Pierrick; Ellegaard, Kirsten; Allen, Judith E.; Little, Tom J.

2011-01-01

The last ten years have witnessed increasing interest in host–pathogen interactions involving invertebrate hosts. The invertebrate innate immune system is now relatively well characterised, but in a limited range of genetic model organisms and under a limited number of conditions. Immune systems have been little studied under real-world scenarios of environmental variation and parasitism. Thus, we have investigated expression of candidate innate immune system genes in the water flea Daphnia, a model organism for ecological genetics, and whose capacity for clonal reproduction facilitates an exceptionally rigorous control of exposure dose or the study of responses at many time points. A unique characteristic of the particular Daphnia clones and pathogen strain combinations used presently is that they have been shown to be involved in specific host–pathogen coevolutionary interactions in the wild. We choose five genes, which are strong candidates to be involved in Daphnia–pathogen interactions, given that they have been shown to code for immune effectors in related organisms. Differential expression of these genes was quantified by qRT-PCR following exposure to the bacterial pathogen Pasteuria ramosa. Constitutive expression levels differed between host genotypes, and some genes appeared to show correlated expression. However, none of the genes appeared to show a major modification of expression level in response to Pasteuria exposure. By applying knowledge from related genetic model organisms (e.g. Drosophila) to models for the study of evolutionary ecology and coevolution (i.e. Daphnia), the candidate gene approach is temptingly efficient. However, our results show that detection of only weak patterns is likely if one chooses target genes for study based on previously identified genome sequences by comparison to homologues from other related organisms. Future work on the Daphnia–Pasteuria system will need to balance a candidate gene approach with more
Candidate innate immune system gene expression in the ecological model Daphnia.

PubMed

Decaestecker, Ellen; Labbé, Pierrick; Ellegaard, Kirsten; Allen, Judith E; Little, Tom J

2011-10-01

The last ten years have witnessed increasing interest in host-pathogen interactions involving invertebrate hosts. The invertebrate innate immune system is now relatively well characterised, but in a limited range of genetic model organisms and under a limited number of conditions. Immune systems have been little studied under real-world scenarios of environmental variation and parasitism. Thus, we have investigated expression of candidate innate immune system genes in the water flea Daphnia, a model organism for ecological genetics, and whose capacity for clonal reproduction facilitates an exceptionally rigorous control of exposure dose or the study of responses at many time points. A unique characteristic of the particular Daphnia clones and pathogen strain combinations used presently is that they have been shown to be involved in specific host-pathogen coevolutionary interactions in the wild. We choose five genes, which are strong candidates to be involved in Daphnia-pathogen interactions, given that they have been shown to code for immune effectors in related organisms. Differential expression of these genes was quantified by qRT-PCR following exposure to the bacterial pathogen Pasteuria ramosa. Constitutive expression levels differed between host genotypes, and some genes appeared to show correlated expression. However, none of the genes appeared to show a major modification of expression level in response to Pasteuria exposure. By applying knowledge from related genetic model organisms (e.g. Drosophila) to models for the study of evolutionary ecology and coevolution (i.e. Daphnia), the candidate gene approach is temptingly efficient. However, our results show that detection of only weak patterns is likely if one chooses target genes for study based on previously identified genome sequences by comparison to homologues from other related organisms. Future work on the Daphnia-Pasteuria system will need to balance a candidate gene approach with more comprehensive
Thiamine supplementation facilitates thiamine transporter expression in the rumen epithelium and attenuates high-grain-induced inflammation in low-yielding dairy cows.

PubMed

Pan, X H; Yang, L; Beckers, Y; Xue, F G; Tang, Z W; Jiang, L S; Xiong, B H

2017-07-01

An experiment was conducted to uncover the effects of increasing dietary grain levels on expression of thiamine transporters in ruminal epithelium, and to assess the protective effects of thiamine against high-grain-induced inflammation in dairy cows. Six rumen-fistulated, lactating Holstein dairy cows (627 ± 16.9 kg of body weight, 180 ± 6 d in milk; mean ± standard deviation) were randomly assigned to a replicated 3 × 3 Latin square design trial. Three treatments were control (20% dietary starch, dry matter basis), high-grain diet (HG, 33.2% dietary starch, DM basis), and HG diet supplemented with 180 mg of thiamine/kg of dry matter intake. On d 19 and 20 of each period, milk performance was measured. On d 21, ruminal pH, endotoxic lipopolysaccharide (LPS), and thiamine contents in rumen and blood, and plasma inflammatory cytokines were detected; a rumen papillae biopsy was taken on d 21 to determine the gene and protein expression of toll-like receptor 4 (TLR4) signaling pathways. The HG diet decreased ruminal pH (5.93 vs. 6.49), increased milk yield from 17.9 to 20.2 kg/d, and lowered milk fat and protein from 4.28 to 3.83%, and from 3.38 to 3.11%, respectively. The HG feeding reduced thiamine content in rumen (2.89 vs. 8.97 μg/L) and blood (11.66 vs. 17.63 μg/L), and the relative expression value of thiamine transporter-2 (0.37-fold) and mitochondrial thiamine pyrophosphate transporter (0.33-fold) was downregulated by HG feeding. The HG-fed cows exhibited higher endotoxin LPS in rumen fluid (134,380 vs. 11,815 endotoxin units/mL), and higher plasma concentrations of lipopolysaccharide binding protein and pro-inflammatory cytokines when compared with the control group. The gene and protein expression of tumor necrosis factor α (TNFα), IL1B, and IL6 in rumen epithelium increased when cows were fed the HG diet, indicating that local inflammation occurred. The depressions in ruminal pH, milk fat, and protein of HG-fed cows were reversed by thiamine
Gene and transcript abundances of bacterial type III secretion systems from the rumen microbiome are correlated with methane yield in sheep.

PubMed

Kamke, Janine; Soni, Priya; Li, Yang; Ganesh, Siva; Kelly, William J; Leahy, Sinead C; Shi, Weibing; Froula, Jeff; Rubin, Edward M; Attwood, Graeme T

2017-08-08

Ruminants are important contributors to global methane emissions via microbial fermentation in their reticulo-rumens. This study is part of a larger program, characterising the rumen microbiomes of sheep which vary naturally in methane yield (g CH 4 /kg DM/day) and aims to define differences in microbial communities, and in gene and transcript abundances that can explain the animal methane phenotype. Rumen microbiome metagenomic and metatranscriptomic data were analysed by Gene Set Enrichment, sparse partial least squares regression and the Wilcoxon Rank Sum test to estimate correlations between specific KEGG bacterial pathways/genes and high methane yield in sheep. KEGG genes enriched in high methane yield sheep were reassembled from raw reads and existing contigs and analysed by MEGAN to predict their phylogenetic origin. Protein coding sequences from Succinivibrio dextrinosolvens strains were analysed using Effective DB to predict bacterial type III secreted proteins. The effect of S. dextrinosolvens strain H5 growth on methane formation by rumen methanogens was explored using co-cultures. Detailed analysis of the rumen microbiomes of high methane yield sheep shows that gene and transcript abundances of bacterial type III secretion system genes are positively correlated with methane yield in sheep. Most of the bacterial type III secretion system genes could not be assigned to a particular bacterial group, but several genes were affiliated with the genus Succinivibrio, and searches of bacterial genome sequences found that strains of S. dextrinosolvens were part of a small group of rumen bacteria that encode this type of secretion system. In co-culture experiments, S. dextrinosolvens strain H5 showed a growth-enhancing effect on a methanogen belonging to the order Methanomassiliicoccales, and inhibition of a representative of the Methanobrevibacter gottschalkii clade. This is the first report of bacterial type III secretion system genes being associated with high
Compact liquid nitrogen storage system yielding high recoveries of gram-negative anaerobes.

PubMed Central

Gilmour, M N; Turner, G; Berman, R G; Krenzer, A K

1978-01-01

A simple and compact system suitable for the preservation of fragile gram negative anaerobes and other bacteria in liquid N2 has been developed. Polypropylene straws used as specimen containers can be used easily within glove bags of anaerobic chambers, and their small size greatly increases the number of cultures which can be stored. Ancillary equipment and methods developed are described. The overall system was tested, using Streptococcus mutans, Fusobacterium nucleatum, and Selenomonas sputigena. Various basal suspending fluids and cryoprotective supplements were studied. With fast rates of freezing and thawing, survival recoveries of the test microorganisms ranged from 80 to 100 percent of the input colony-forming units in a complex medium broth base without cryoprotective agent addition, and they consistently were 100 percent when 0.4 mM polyvinylpyrrolidine was used. Overall, cryoprotection by polyvinyl pyrrolidine was superior to that from glycerol or dimethyl sulfoxide, the latter yielding recoveries similar to or less than those obtained with no cryoprotectant additive. All microorganisms were recoverable after storage for 1 year. PMID:623475
Short-term complete submergence of rice at the tillering stage increases yield.

PubMed

Zhang, Yajie; Wang, Zhensheng; Li, Lei; Zhou, Qun; Xiao, Yao; Wei, Xing; Zhou, Mingyao

2015-01-01

Flooding is a major threat to agricultural production. Most studies have focused on the lower water storage limit in rice fields, whereas few studies have examined the upper water storage limit. This study aimed to explore the effect of waterlogging at the rice tillering stage on rice growth and yield. The early-ripening late japonica variety Yangjing 4227 was selected for this study. The treatments included different submergence depths (submergence depth/plant height: 1/2 (waist submergence), 2/3 (neck submergence), and 1/1 (complete submergence)) and durations (1, 3, and 5 d). The control group was treated with the conventional alternation of drying and wetting. The effects of waterlogging at the tillering stage on root characteristics, dry matter production, nitrogen and phosphorus accumulation, yield, yield components, and 1-aminocyclopropane-1-carboxylic acid synthase (ACS) gene expression were explored. Compared with the control group, the 1/1 group showed significant increases in yield, seed-setting rate, photosynthetically efficient leaf area, and OS-ACS3 gene expression after 1 d of submergence. The grain number per panicle, dry weight of the aboveground and belowground parts, and number of adventitious roots also increased. Correlation analysis revealed a significant positive correlation between the panicle number and nitrogen content; however, no significant correlation was found for phosphorus content. If a decrease in rice yield of less than 10% is acceptable, half, 2/3, and complete submergence of the plants can be performed at the tillering stage for 1-3 d; this treatment will increase the space available for rice field water management/control and will improve rainfall resource utilization.
Analytical expressions for the nonlinear interference in dispersion managed transmission coherent optical systems

NASA Astrophysics Data System (ADS)

Qiao, Yaojun; Li, Ming; Yang, Qiuhong; Xu, Yanfei; Ji, Yuefeng

2015-01-01

Closed-form expressions of nonlinear interference of dense wavelength-division-multiplexed (WDM) systems with dispersion managed transmission (DMT) are derived. We carry out a simulative validation by addressing an ample and significant set of the Nyquist-WDM systems based on polarization multiplexed quadrature phase-shift keying (PM-QPSK) subcarriers at a baud rate of 32 Gbaud per channel. Simulation results show the simple closed-form analytical expressions can provide an effective tool for the quick and accurate prediction of system performance in DMT coherent optical systems.
Yield and failure criteria for composite materials under static and dynamic loading

DOE PAGES

Daniel, Isaac M.

2015-12-23

To facilitate and accelerate the process of introducing, evaluating and adopting of new material systems, it is important to develop/establish comprehensive and effective procedures of characterization, modeling and failure prediction of structural laminates based on the properties of the constituent materials, e. g., fibers, matrix, and the single ply or lamina. A new failure theory, the Northwestern (NU-Daniel) theory, has been proposed for predicting lamina yielding and failure under multi-axial states of stress including strain rate effects. It is primarily applicable to matrix-dominated interfiber/interlaminar failures. It is based on micromechanical failure mechanisms but is expressed in terms of easily measuredmore » macroscopic lamina stiffness and strength properties. It is presented in the form of a master failure envelope incorporating strain rate effects. The theory was further adapted and extended to the prediction of in situ first ply yielding and failure (FPY and FPF) and progressive failure of multi-directional laminates under static and dynamic loadings. The significance of this theory is that it allows for rapid screening of new composite materials without very extensive testing and offers easily implemented design tools.« less
Stable expression and purification of a functional processed Fab' fragment from a single nascent polypeptide in CHO cells expressing the mCAT-1 retroviral receptor.

PubMed

Camper, Nicolas; Byrne, Teresa; Burden, Roberta E; Lowry, Jenny; Gray, Breena; Johnston, James A; Migaud, Marie E; Olwill, Shane A; Buick, Richard J; Scott, Christopher J

2011-09-30

Monoclonal antibodies and derivative formats such as Fab' fragments are used in a broad range of therapeutic, diagnostic and research applications. New systems and methodologies that can improve the production of these proteins are consequently of much interest. Here we present a novel approach for the rapid production of processed Fab' fragments in a CHO cell line that has been engineered to express the mouse cationic amino acid transporter receptor 1 (mCAT-1). This facilitated the introduction of the target antibody gene through retroviral transfection, rapidly producing stable expression. Using this system, we designed a single retroviral vector construct for the expression of a target Fab' fragment as a single polypeptide with a furin cleavage site and a FMDV 2A self-cleaving peptide introduced to bridge the light and truncated heavy chain regions. The introduction of these cleavage motifs ensured equimolar expression and processing of the heavy and light domains as exemplified by the production of an active chimeric Fab' fragment against the Fas receptor, routinely expressed in 1-2mg/L yield in spinner-flask cell cultures. These results demonstrate that this method could have application in the facile production of bioactive Fab' fragments. Copyright © 2011 Elsevier B.V. All rights reserved.
Separating out the influence of climatic trend, fluctuations, and extreme events on crop yield: a case study in Hunan Province, China

NASA Astrophysics Data System (ADS)

Wang, Zhu; Shi, Peijun; Zhang, Zhao; Meng, Yongchang; Luan, Yibo; Wang, Jiwei

2017-09-01

Separating out the influence of climatic trend, fluctuations and extreme events on crop yield is of paramount importance to climate change adaptation, resilience, and mitigation. Previous studies lack systematic and explicit assessment of these three fundamental aspects of climate change on crop yield. This research attempts to separate out the impacts on rice yields of climatic trend (linear trend change related to mean value), fluctuations (variability surpassing the "fluctuation threshold" which defined as one standard deviation (1 SD) of the residual between the original data series and the linear trend value for each climatic variable), and extreme events (identified by absolute criterion for each kind of extreme events related to crop yield). The main idea of the research method was to construct climate scenarios combined with crop system simulation model. Comparable climate scenarios were designed to express the impact of each climate change component and, were input to the crop system model (CERES-Rice), which calculated the related simulated yield gap to quantify the percentage impacts of climatic trend, fluctuations, and extreme events. Six Agro-Meteorological Stations (AMS) in Hunan province were selected to study the quantitatively impact of climatic trend, fluctuations and extreme events involving climatic variables (air temperature, precipitation, and sunshine duration) on early rice yield during 1981-2012. The results showed that extreme events were found to have the greatest impact on early rice yield (-2.59 to -15.89%). Followed by climatic fluctuations with a range of -2.60 to -4.46%, and then the climatic trend (4.91-2.12%). Furthermore, the influence of climatic trend on early rice yield presented "trade-offs" among various climate variables and AMS. Climatic trend and extreme events associated with air temperature showed larger effects on early rice yield than other climatic variables, particularly for high-temperature events (-2.11 to -12
Measurement of fission yields and isomeric yield ratios at IGISOL

NASA Astrophysics Data System (ADS)

Pomp, Stephan; Mattera, Andrea; Rakopoulos, Vasileios; Al-Adili, Ali; Lantz, Mattias; Solders, Andreas; Jansson, Kaj; Prokofiev, Alexander V.; Eronen, Tommi; Gorelov, Dimitri; Jokinen, Ari; Kankainen, Anu; Moore, Iain D.; Penttilä, Heikki; Rinta-Antila, Sami

2018-03-01

Data on fission yields and isomeric yield ratios (IYR) are tools to study the fission process, in particular the generation of angular momentum. We use the IGISOL facility with the Penning trap JYFLTRAP in Jyväskylä, Finland, for such measurements on 232Th and natU targets. Previously published fission yield data from IGISOL concern the 232Th(p,f) and 238U(p,f) reactions at 25 and 50 MeV. Recently, a neutron source, using the Be(p,n) reaction, has been developed, installed and tested. We summarize the results for (p,f) focusing on the first measurement of IYR by direct ion counting. We also present first results for IYR and relative yields for Sn and Sb isotopes in the 128-133 mass range from natU(n,f) based on γ-spectrometry. We find a staggering behaviour in the cumulative yields for Sn and a shift in the independent fission yields for Sb as compared to current evaluations. Plans for the future experimental program on fission yields and IYR measurements are discussed.
Identification and expression of the protein ubiquitination system in Giardia intestinalis.

PubMed

Gallego, Eva; Alvarado, Magda; Wasserman, Moises

2007-06-01

Giardia intestinalis is a single-cell eukaryotic microorganism, regarded as one of the earliest divergent eukaryotes and thus an attractive model to study the evolution of regulatory systems. Giardia has two different forms throughout its life cycle, cyst and trophozoite, and changes from one to the other in response to environmental signals. The two differentiation processes involve a differential gene expression as well as a quick and specific protein turnover that may be mediated by the ubiquitin/proteasome system. The aim of this work was to search for unreported components of the ubiquitination system and to experimentally demonstrate their expression in the parasite and during the two differentiation processes. We found activity of protein ubiquitination in G. intestinalis trophozoites and analyzed the transcription of the ubiquitin gene, as well as that of the activating (E1), conjugating (E2), and ligase (E3) ubiquitin enzymes during encystation and excystation. A constant ubiquitin expression persisted during the parasite's differentiation processes, whereas variation in transcription was observed in the other genes under study.
Bacterial-based systems for expression and purification of recombinant Lassa virus proteins of immunological relevance

PubMed Central

Branco, Luis M; Matschiner, Alex; Fair, Joseph N; Goba, Augustine; Sampey, Darryl B; Ferro, Philip J; Cashman, Kathleen A; Schoepp, Randal J; Tesh, Robert B; Bausch, Daniel G; Garry, Robert F; Guttieri, Mary C

2008-01-01

Background There is a significant requirement for the development and acquisition of reagents that will facilitate effective diagnosis, treatment, and prevention of Lassa fever. In this regard, recombinant Lassa virus (LASV) proteins may serve as valuable tools in diverse antiviral applications. Bacterial-based systems were engineered for expression and purification of recombinant LASV nucleoprotein (NP), glycoprotein 1 (GP1), and glycoprotein 2 (GP2). Results Full-length NP and the ectodomains of GP1 and GP2 were generated as maltose-binding protein (MBP) fusions in the Rosetta strains of Escherichia coli (E. coli) using pMAL-c2x vectors. Average fusion protein yields per liter of culture for MBP-NP, MBP-GP1, and MBP-GP2 were 10 mg, 9 mg, and 9 mg, respectively. Each protein was captured from cell lysates using amylose resin, cleaved with Factor Xa, and purified using size-exclusion chromatography (SEC). Fermentation cultures resulted in average yields per liter of 1.6 mg, 1.5 mg, and 0.7 mg of purified NP, GP1 and GP2, respectively. LASV-specific antibodies in human convalescent sera specifically detected each of the purified recombinant LASV proteins, highlighting their utility in diagnostic applications. In addition, mouse hyperimmune ascitic fluids (MHAF) against a panel of Old and New World arenaviruses demonstrated selective cross reactivity with LASV proteins in Western blot and enzyme-linked immunosorbent assay (ELISA). Conclusion These results demonstrate the potential for developing broadly reactive immunological assays that employ all three arenaviral proteins individually and in combination. PMID:18538016
Functional expression of an ajmaline pathway-specific esterase from Rauvolfia in a novel plant-virus expression system.

PubMed

Ruppert, Martin; Woll, Jörn; Giritch, Anatoli; Genady, Ezzat; Ma, Xueyan; Stöckigt, Joachim

2005-11-01

Acetylajmalan esterase (AAE) plays an essential role in the late stage of ajmaline biosynthesis. Based on the partial peptide sequences of AAE isolated and purified from Rauvolfia cell suspensions, a full-length AAE cDNA clone was isolated. The amino acid sequence of AAE has the highest level of identity of 40% to putative lipases known from the Arabidopsis thaliana genome project. Based on the primary structure AAE is a new member of the GDSL lipase superfamily. The expression in Escherichia coli failed although a wide range of conditions were tested. With a novel virus-based plant expression system, it was possible to express AAE functionally in leaves of Nicotiana benthamiana Domin. An extraordinarily high enzyme activity was detected in the Nicotiana tissue, which exceeded that in Rauvolfia serpentina (L.) Benth. ex Kurz cell suspension cultures about 20-fold. This expression allowed molecular analysis of AAE for the first time and increased the number of functionally expressed alkaloid genes from Rauvolfia now to eight, and the number of ajmaline pathway-specific cDNAs to a total of six.
GAPTrap: A Simple Expression System for Pluripotent Stem Cells and Their Derivatives.

PubMed

Kao, Tim; Labonne, Tanya; Niclis, Jonathan C; Chaurasia, Ritu; Lokmic, Zerina; Qian, Elizabeth; Bruveris, Freya F; Howden, Sara E; Motazedian, Ali; Schiesser, Jacqueline V; Costa, Magdaline; Sourris, Koula; Ng, Elizabeth; Anderson, David; Giudice, Antonietta; Farlie, Peter; Cheung, Michael; Lamande, Shireen R; Penington, Anthony J; Parish, Clare L; Thomson, Lachlan H; Rafii, Arash; Elliott, David A; Elefanty, Andrew G; Stanley, Edouard G

2016-09-13

The ability to reliably express fluorescent reporters or other genes of interest is important for using human pluripotent stem cells (hPSCs) as a platform for investigating cell fates and gene function. We describe a simple expression system, designated GAPTrap (GT), in which reporter genes, including GFP, mCherry, mTagBFP2, luc2, Gluc, and lacZ are inserted into the GAPDH locus in hPSCs. Independent clones harboring variations of the GT vectors expressed remarkably consistent levels of the reporter gene. Differentiation experiments showed that reporter expression was reliably maintained in hematopoietic cells, cardiac mesoderm, definitive endoderm, and ventral midbrain dopaminergic neurons. Similarly, analysis of teratomas derived from GT-lacZ hPSCs showed that β-galactosidase expression was maintained in a spectrum of cell types representing derivatives of the three germ layers. Thus, the GAPTrap vectors represent a robust and straightforward tagging system that enables indelible labeling of PSCs and their differentiated derivatives. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Main Strategies of Plant Expression System Glycoengineering for Producing Humanized Recombinant Pharmaceutical Proteins.

PubMed

Rozov, S M; Permyakova, N V; Deineko, E V

2018-03-01

Most the pharmaceutical proteins are derived not from their natural sources, rather their recombinant analogs are synthesized in various expression systems. Plant expression systems, unlike mammalian cell cultures, combine simplicity and low cost of procaryotic systems and the ability for posttranslational modifications inherent in eucaryotes. More than 50% of all human proteins and more than 40% of the currently used pharmaceutical proteins are glycosylated, that is, they are glycoproteins, and their biological activity, pharmacodynamics, and immunogenicity depend on the correct glycosylation pattern. This review examines in detail the similarities and differences between N- and O-glycosylation in plant and mammalian cells, as well as the effect of plant glycans on the activity, pharmacokinetics, immunity, and intensity of biosynthesis of pharmaceutical proteins. The main current strategies of glycoengineering of plant expression systems aimed at obtaining fully humanized proteins for pharmaceutical application are summarized.
Prognostic impact of MYC protein expression in central nervous system diffuse large B-cell lymphoma: comparison with MYC rearrangement and MYC mRNA expression.

PubMed

Son, Seung-Myoung; Ha, Sang-Yun; Yoo, Hae-Yong; Oh, Dongryul; Kim, Seok-Jin; Kim, Won-Seog; Ko, Young-Hyeh

2017-01-01

The prognostic role of MYC has been well documented in non-central nervous system diffuse large B-cell lymphoma; however, it remains controversial in central nervous system diffuse large B-cell lymphoma. To investigate the prognostic value of MYC, we analyzed the MYC protein expression by immunohistochemistry, mRNA expression by RNA in situ hybridization, and gene status by fluorescence in situ hybridization in 74 cases of central nervous system diffuse large B-cell lymphoma. Moreover, we examined the correlation between MYC translocation, mRNA expression, and protein expression. The mean percentage of MYC immunopositive cells was 49%. Using a 44% cutoff value, 49 (66%) cases showed MYC protein overexpression. The result of mRNA in situ hybridization using the RNA scope technology was obtained using the H-scoring system; the median value was 34.2. Using the cutoff value of 63.5, 16 (22%) cases showed MYC mRNA overexpression. MYC gene rearrangement was detected in five out of 68 (7%) cases. MYC translocation showed no statistically significant correlation with mRNA expression; however, all MYC translocation-positive cases showed MYC protein overexpression, with a higher mean percentage of MYC protein expression than that of translocation-negative cases (78 vs 48%, P=0.001). The level of MYC mRNA expression was moderately correlated with the level of MYC protein expression (P<0.001). The mean percentage of MYC protein expression in the high MYC mRNA group was higher than that in the low MYC mRNA group (70 vs 47%, P<0.001). A univariate analysis showed that age over 60 years, Eastern Cooperative Oncology Group (ECOG) performance status ≥2 and MYC protein overexpression were significantly associated with an increased risk of death. MYC translocation and MYC mRNA expression had no prognostic significance. On multivariate analysis, MYC protein overexpression and ECOG score retained prognostic significance.
Expression of glypican-3 is highly associated with pediatric hepatoblastoma: a systemic analysis.

PubMed

Xiong, Xiao-Li; Qin, Huan; Yan, Su-Qi; Zhou, Li-Shan; Chen, Peng; Zhao, Dong- Chi

2015-01-01

Glypican-3 (GPC3) is reported to be an oncofetal protein that is a useful diagnostic immunomarker for hepatoblastoma. However, the results are not inclusive. This study systemically investigated the association between expression of GPC3 and pediatric hepatoblastoma. Clinical studies evaluating the association were identified using a predefined search strategy. GPC3 immunohistochemistry was applied in the pathological diagnosis of hepatoblastoma using the monoclonal antibodies with formalin-fixed and paraffin-embedded specimens. Positive predictive rates for the association between expression of GPC3 and pediatric hepatoblastoma were calculated. Specimens from four clinical studies which including 134 patients with pediatric hepatoblastoma tested by GPC3 immunohistochemistry were considered eligible for inclusion. Systemic analysis showed that, in all patients, pooled positive predictive rate of the association between expression of GPC3 and pediatric hepatoblastoma was 95.5% (128/134). This systemic analysis suggests that the expression of glypican-3 is highly associated with the diagnosis of pediatric hepatoblastoma.
Systemic Sclerosis Patients Present Alterations in the Expression of Molecules Involved in B-Cell Regulation

PubMed Central

Soto, Lilian; Ferrier, Ashley; Aravena, Octavio; Fonseca, Elianet; Berendsen, Jorge; Biere, Andrea; Bueno, Daniel; Ramos, Verónica; Aguillón, Juan Carlos; Catalán, Diego

2015-01-01

The activation threshold of B cells is tightly regulated by an array of inhibitory and activator receptors in such a way that disturbances in their expression can lead to the appearance of autoimmunity. The aim of this study was to evaluate the expression of activating and inhibitory molecules involved in the modulation of B cell functions in transitional, naive, and memory B-cell subpopulations from systemic sclerosis patients. To achieve this, blood samples were drawn from 31 systemic sclerosis patients and 53 healthy individuals. Surface expression of CD86, MHC II, CD19, CD21, CD40, CD22, Siglec 10, CD35, and FcγRIIB was determined by flow cytometry. IL-10 production was evaluated by intracellular flow cytometry from isolated B cells. Soluble IL-6 and IL-10 levels were measured by ELISA from supernatants of stimulated B cells. Systemic sclerosis patients exhibit an increased frequency of transitional and naive B cells related to memory B cells compared with healthy controls. Transitional and naive B cells from patients express higher levels of CD86 and FcγRIIB than healthy donors. Also, B cells from patients show high expression of CD19 and CD40, whereas memory cells from systemic sclerosis patients show reduced expression of CD35. CD19 and CD35 expression levels associate with different autoantibody profiles. IL-10+ B cells and secreted levels of IL-10 were markedly reduced in patients. In conclusion, systemic sclerosis patients show alterations in the expression of molecules involved in B-cell regulation. These abnormalities may be determinant in the B-cell hyperactivation observed in systemic sclerosis. PMID:26483788

Slope Controls Grain Yield and Climatic Yield in Mountainous Yunnan province, China

NASA Astrophysics Data System (ADS)

Duan, X.; Rong, L.; Gu, Z.; Feng, D.

2017-12-01

Mountainous regions are increasingly vulnerable to food insecurity because of limited arable land, growing population pressure, and climate change. Development of sustainable mountain agriculture will require an increased understanding of the effects of environmental factors on grain and climatic yields. The objective of this study was to explore the relationships between actual grain yield, climatic yield, and environmental factors in a mountainous region in China. We collected data on the average grain yield per unit area in 119 counties in Yunnan province from 1985 to 2012, and chose 17 environmental factors for the same period. Our results showed that actual grain yield ranged from 1.43 to 6.92 t·ha-1, and the climatic yield ranged from -0.15 to -0.01 t·ha-1. Lower climatic yield but higher grain yield was generally found in central areas and at lower slopes and elevations in the western and southwestern counties of Yunnan province. Higher climatic yield but lower grain yield were found in northwestern parts of Yunnan province on steep slopes. Annual precipation and temperature had a weak influence on the climatic yield. Slope explained 44.62 and 26.29% of the variation in grain yield and climatic yield. The effects of topography on grain and climatic yields were greater than climatic factors. Slope was the most important environmental variable for the variability in climatic and grain yields in the mountainous Yunnan province due to the highly heterogeneous topographic conditions. Conversion of slopes to terraces in areas with higher climatic yields is an effective way to maintain grain production in response to climate variability. Additionally, soil amendments and soil and water conservation measures should be considered to maintain soil fertility and aid in sustainable development in central areas, and in counties at lower slopes and elevations in western and southwestern Yunnan province.
[Effects of irrigation using dairy effluent on grain yield, phosphorus utilization and distribu- tion in soil profile in winter wheat-summer maize rotation system].

PubMed

Du, Hui-ying; Feng, Jie; Guo, Hai-gang; Wang, Feng; Zhang, Ke-qiang

2015-08-01

Field experiments of winter wheat-summer maize rotation were conducted in North China Plain irrigation area to explore the effects of wheat season irrigation with dairy effluent on grain yield, phosphorus uptake, accumulative phosphorus usage efficiency and phosphorus accumulation in soil. The results showed that the irrigation with dairy effluent significantly improved the yields of winter wheat and summer maize. With the increasing of P2O5 carried by dairy effluent into soil, winter wheat yield increased at first and then decreased. When the P2O5 increased 137 kg · hm(-2), winter wheat yield increased to the maximum (7646.4 kg · hm(-2)) and the phosphorus utilization rate was the highest (24.8%). But excessive phosphorus decreased the winter wheat yield and phosphorus utilization efficiency. Summer maize yield and phosphorus uptake increased with the increase of P2O5 carried by dairy effluent. The summer maize yield increased by 2222.4-2628.6 kg · hm(-2) and the phosphorus uptake increased by 13.9-21.1 kg · hm(-2) in contrast to the control (CK). Under conventional phosphorus fertilization at 88 kg · hm(-2), and the summer maize yield increased by 2235.0 kg · hm(-2) compared with CK. As the time of irrigation with dairy effluent increasing, the grain yield increased more significantly. The cumulative phosphorus utilization in this rotation system increased year by year. After six seasons of crop harvest, the cumulative phosphorus utilization rate increased into 40.0%-47.7%. Under the experimental condition, two times of irrigation with the dairy effluents in the winter wheat-summer maize rotation system was the best operating mode.
A Rare Allele of GS2 Enhances Grain Size and Grain Yield in Rice.

PubMed

Hu, Jiang; Wang, Yuexing; Fang, Yunxia; Zeng, Longjun; Xu, Jie; Yu, Haiping; Shi, Zhenyuan; Pan, Jiangjie; Zhang, Dong; Kang, Shujing; Zhu, Li; Dong, Guojun; Guo, Longbiao; Zeng, Dali; Zhang, Guangheng; Xie, Lihong; Xiong, Guosheng; Li, Jiayang; Qian, Qian

2015-10-05

Grain size determines grain weight and affects grain quality. Several major quantitative trait loci (QTLs) regulating grain size have been cloned; however, our understanding of the underlying mechanism that regulates the size of rice grains remains fragmentary. Here, we report the cloning and characterization of a dominant QTL, grain size on chromosome 2 (GS2), which encodes Growth-Regulating Factor 4 (OsGRF4), a transcriptional regulator. GS2 localizes to the nucleus and may act as a transcription activator. A rare mutation of GS2 affecting the binding site of a microRNA, OsmiR396c, causes elevated expression of GS2/OsGRF4. The increase in GS2 expression leads to larger cells and increased numbers of cells, which thus enhances grain weight and yield. The introduction of this rare allele of GS2/OsGRF4 into rice cultivars could significantly enhance grain weight and increase grain yield, with possible applications in breeding high-yield rice varieties. Copyright © 2015 The Author. Published by Elsevier Inc. All rights reserved.
AMTEC radioisotope power system design and analysis for Pluto Express Fly-By

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

Hendricks, T.J.; Huang, C.; Sievers, R.K.

1997-12-31

The Pluto Express Fly-By program requires a Radioisotope Power System (RPS) to supply spacecraft power for various internal functions and mission instruments and experiments. AMTEC (Alkali-Metal Thermal-Electric Conversion) power conversion is the DOE-selected technology for an advanced, high-efficiency RPS to power the Pluto Express Fly-By spacecraft. An AMTEC-based RPS using the General Purpose Heat Source (GPHS) has been conceptually designed to satisfy the Pluto Express power requirements. Integrated AMTEC cell and system thermal/electrical design analyses, structural design analyses, and mass analyses were performed to define an optimum system design. Using fresh radioisotope fuel at beginning of mission, the RPS producesmore » 102 watts of power, has a mass of 8.35 kg (specific power density = 12.2 watts/kg), with a system conversion efficiency of 20.3%. Mass/power scale-up estimates have also been generated, indicating that a 150-watt version of this RPS would weigh approximately 11.3 kg. This paper presents and discusses the key features of this RPS design, the design and analysis methodology, and the numerous system and AMTEC cell tradeoff studies establishing the optimum AMTEC-based RPS.« less
Quantum Yields in Mixed-Conifer Forests and Ponderosa Pine Plantations

NASA Astrophysics Data System (ADS)

Wei, L.; Marshall, J. D.; Zhang, J.

2008-12-01

Most process-based physiological models require canopy quantum yield of photosynthesis as a starting point to simulate carbon sequestration and subsequently gross primary production (GPP). The quantum yield is a measure of photosynthetic efficiency expressed in moles of CO2 assimilated per mole of photons absorbed; the process is influenced by environmental factors. In the summer 2008, we measured quantum yields on both sun and shade leaves for four conifer species at five sites within Mica Creek Experimental Watershed (MCEW) in northern Idaho and one conifer species at three sites in northern California. The MCEW forest is typical of mixed conifer stands dominated by grand fir (Abies grandis (Douglas ex D. Don) Lindl.). In northern California, the three sites with contrasting site qualities are ponderosa pine (Pinus ponderosa C. Lawson var. ponderosa) plantations that were experimentally treated with vegetation control, fertilization, and a combination of both. We found that quantum yields in MCEW ranged from ~0.045 to ~0.075 mol CO2 per mol incident photon. However, there were no significant differences between canopy positions, or among sites or tree species. In northern California, the mean value of quantum yield of three sites was 0.051 mol CO2/mol incident photon. No significant difference in quantum yield was found between canopy positions, or among treatments or sites. The results suggest that these conifer species maintain relatively consistent quantum yield in both MCEW and northern California. This consistency simplifies the use of a process-based model to accurately predict forest productivity in these areas.
Coordinated regulation of photosynthesis in rice increases yield and tolerance to environmental stress

PubMed Central

Ambavaram, Madana M. R.; Basu, Supratim; Krishnan, Arjun; Ramegowda, Venkategowda; Batlang, Utlwang; Rahman, Lutfor; Baisakh, Niranjan; Pereira, Andy

2014-01-01

Plants capture solar energy and atmospheric carbon dioxide (CO2) through photosynthesis, which is the primary component of crop yield, and needs to be increased considerably to meet the growing global demand for food. Environmental stresses, which are increasing with climate change, adversely affect photosynthetic carbon metabolism (PCM) and limit yield of cereals such as rice (Oryza sativa) that feeds half the world. To study the regulation of photosynthesis, we developed a rice gene regulatory network and identified a transcription factor HYR (HIGHER YIELD RICE) associated with PCM, which on expression in rice enhances photosynthesis under multiple environmental conditions, determining a morpho-physiological programme leading to higher grain yield under normal, drought and high-temperature stress conditions. We show HYR is a master regulator, directly activating photosynthesis genes, cascades of transcription factors and other downstream genes involved in PCM and yield stability under drought and high-temperature environmental stress conditions. PMID:25358745
Geminivirus vectors for high-level expression of foreign proteins in plant cells.

PubMed

Mor, Tsafrir S; Moon, Yong-Sun; Palmer, Kenneth E; Mason, Hugh S

2003-02-20

Bean yellow dwarf virus (BeYDV) is a monopartite geminivirus that can infect dicotyledonous plants. We have developed a high-level expression system that utilizes elements of the replication machinery of this single-stranded DNA virus. The replication initiator protein (Rep) mediates release and replication of a replicon from a DNA construct ("LSL vector") that contains an expression cassette for a gene of interest flanked by cis-acting elements of the virus. We used tobacco NT1 cells and biolistic delivery of plasmid DNA for evaluation of replication and expression of reporter genes contained within an LSL vector. By codelivery of a GUS reporter-LSL vector and a Rep-supplying vector, we obtained up to 40-fold increase in expression levels compared to delivery of the reporter-LSL vectors alone. High-copy replication of the LSL vector was correlated with enhanced expression of GUS. Rep expression using a whole BeYDV clone, a cauliflower mosaic virus 35S promoter driving either genomic rep or an intron-deleted rep gene, or 35S-rep contained in the LSL vector all achieved efficient replication and enhancement of GUS expression. We anticipate that this system can be adapted for use in transgenic plants or plant cell cultures with appropriately regulated expression of Rep, with the potential to greatly increase yield of recombinant proteins. Copyright 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 81: 430-437, 2003.
Legume-Cereal Intercropping Improves Forage Yield, Quality and Degradability.

PubMed

Zhang, Jie; Yin, Binjie; Xie, Yuhuai; Li, Jing; Yang, Zaibin; Zhang, Guiguo

2015-01-01

Intercropping legume with cereal is an extensively applied planting pattern in crop cultivation. However, forage potential and the degradability of harvested mixtures from intercropping system remain unclear. To investigate the feasibility of applying an intercropping system as a forage supply source to ruminants, two consecutive experiments (experiments 1 and 2) involving a field cultivation trial and a subsequent in vivo degradable experiment were conducted to determine the forage production performance and the ruminally degradable characteristics of a harvested mixture from an alfalfa/corn-rye intercropping system. In experiment 1, the intercropping system was established by alternating alfalfa and corn or rye with a row ratio of 5:2. Dry matter (DM) and nutrient yields were determined. In experiment 2, forages harvested from the different treatments were used as feedstuff to identify nutrient degradation kinetics and distribution of components between the rapidly degradable (a), potentially degradable (b) and the degradation rate constant (c) of 'b' fraction by in sacco method in Small-Tail Han wether Sheep. The intercropping system of alfalfa and corn-rye provided higher forage production performance with net increases of 9.52% and 34.81% in DM yield, 42.13% and 16.74% in crude protein (CP) yield, 25.94% and 69.99% in degradable DM yield, and 16.96% and 5.50% in degradable CP yield than rotation and alfalfa sole cropping systems, respectively. In addition, the harvest mixture from intercropping system also had greater 'a' fraction, 'b' fraction, 'c' values, and effective degradability (E value) of DM and CP than corn or rye hay harvested from rotation system. After 48-h exposure to rumen microbes, intercropping harvest materials were degraded to a higher extent than separately degraded crop stems from the sole system as indicated by visual microscopic examination with more tissues disappeared. Thus, the intercropping of alfalfa and corn-rye exhibited a greater
Predicting meat yields and commercial meat cuts from carcasses of young bulls of Spanish breeds by the SEUROP method and an image analysis system.

PubMed

Oliver, A; Mendizabal, J A; Ripoll, G; Albertí, P; Purroy, A

2010-04-01

The SEUROP system is currently in use for carcass classification in Europe. Image analysis and other new technologies are being developed to enhance and supplement this classification system. After slaughtering, 91 carcasses of local Spanish beef breeds were weighed and classified according to the SEUROP system. Two digital photographs (a side and a dorsal view) were taken of the left carcass sides, and a total of 33 morphometric measurements (lengths, perimeters, areas) were made. Commercial butchering of these carcasses took place 24 h postmortem, and the different cuts were grouped according to four commercial meat cut quality categories: extra, first, second, and third. Multiple regression analysis of carcass weight and the SEUROP conformation score (x variables) on meat yield and the four commercial cut quality category yields (y variables) was performed as a measure of the accuracy of the SEUROP system. Stepwise regression analysis of carcass weight and the 33 morphometric image analysis measurements (x variables) and meat yield and yields of the four commercial cut quality categories (y variables) was carried out. Higher accuracy was achieved using image analysis than using only the current SEUROP conformation score. The regression coefficient values were between R(2)=0.66 and R(2)=0.93 (P<0.001) for the SEUROP system and between R(2)=0.81 and R(2)=0.94 (P<0.001) for the image analysis method. These results suggest that the image analysis method should be helpful as a means of supplementing and enhancing the SEUROP system for grading beef carcasses. 2009 Elsevier Ltd. All rights reserved.
On the use of the T-REx tetracycline-inducible gene expression system in vivo.

PubMed

Dobrovolsky, Vasily N; Heflich, Robert H

2007-10-15

Components of the commercially available T-REx system were used to create two types of transgenic mice. The first contained the tetracycline-repressor transgene under the control of the CMV promoter/enhancer; the second type contained a green fluorescent protein (GFP) reporter transgene under the control of the CMV promoter/enhancer with a tetracycline repressor operator sequence. Transgene expression was unpredictable in animals containing the individual transgenes. Animals with the reporter transgene expressed GFP in only some tissues (e.g., pancreas, kidney), and one line of reporter transgenic animals developed kidney disease, presumably due to expression of the transgene. The two types of transgenic animals were crossbred to produce double-transgenic animals with the object of regulating the expression of the reporter in vivo. When a similar double-transgenic system was constructed in cultured cells, the repressor protein suppressed the transcription of the reporter transgene. The presence of the repressor in double-transgenic animals had no effect on the expression of the reporter; double transgenic animals developed the same kidney disease that was seen in singly transgenic mice with the reporter. Our results indicate that transgenes under the control of the CMV promoter in the T-REx system express somewhat unpredictably and in only a limited number of tissues, making the use of this system for the development of in vivo models problematical. Copyright 2007 Wiley Periodicals, Inc.
Developing a Hybrid Solar/Wind Powered Drip Irrigation System for Dragon Fruit Yield

NASA Astrophysics Data System (ADS)

Widiastuti, I.; Wijayanto, D. S.

2017-03-01

Irrigation operations take a large amount of water and energy which impact to total costs of crop production. Development of an efficient irrigation supplying precise amount of water and conserving the use of energy can have benefits not only by reducing the operating costs but also by enhancing the farmland productivity. This article presents an irrigation method that promotes sustainable use of water and energy appropriate for a developing tropical country. It proposes a drip irrigation system supported by a combined solar-wind electric power generation system for efficient use of water in dragon fruit cultivation. The electric power generated is used to drive a water pump filling a storage tank for irrigating a 3000 m2 dragon fruit yield in Nguntoronadi, Wonogiri, Indonesia. In designing the irrigation system, the plant’s water requirement was identified based on the value of reference evapotranspiration of the area. A cost/benefit analysis was performed to evaluate the economic feasibility of the proposed scheme. The installation of this solar and wind drip irrigation helps provide sufficient quantity of water to each plant using renewable energy sources which reduce dependence on fossil fuel.
An analysis of yield stability in a conservation agriculture system

USDA-ARS?s Scientific Manuscript database

Climate models predict increasing growing-season weather variability, with negative consequences for crop production. Maintaining agricultural productivity despite variability in weather (i.e., crop yield stability) will be critical to meeting growing global demand. Conservation agriculture is an ...
Alternate Bearing in Citrus: Changes in the Expression of Flowering Control Genes and in Global Gene Expression in ON- versus OFF-Crop Trees

PubMed Central

Shalom, Liron; Samuels, Sivan; Zur, Naftali; Shlizerman, Lyudmila; Zemach, Hanita; Weissberg, Mira; Ophir, Ron; Blumwald, Eduardo; Sadka, Avi

2012-01-01

Alternate bearing (AB) is the process in fruit trees by which cycles of heavy yield (ON crop) one year are followed by a light yield (OFF crop) the next. Heavy yield usually reduces flowering intensity the following year. Despite its agricultural importance, how the developing crop influences the following year's return bloom and yield is not fully understood. It might be assumed that an ‘AB signal’ is generated in the fruit, or in another organ that senses fruit presence, and moves into the bud to determine its fate—flowering or vegetative growth. The bud then responds to fruit presence by altering regulatory and metabolic pathways. Determining these pathways, and when they are altered, might indicate the nature of this putative AB signal. We studied bud morphology, the expression of flowering control genes, and global gene expression in ON- and OFF-crop buds. In May, shortly after flowering and fruit set, OFF-crop buds were already significantly longer than ON-crop buds. The number of differentially expressed genes was higher in May than at the other tested time points. Processes differentially expressed between ON- and OFF-crop trees included key metabolic and regulatory pathways, such as photosynthesis and secondary metabolism. The expression of genes of trehalose metabolism and flavonoid metabolism was validated by nCounter technology, and the latter was confirmed by metabolomic analysis. Among genes induced in OFF-crop trees was one homologous to SQUAMOSA PROMOTER BINDING-LIKE (SPL), which controls juvenile-to-adult and annual phase transitions, regulated by miR156. The expression pattern of SPL-like, miR156 and other flowering control genes suggested that fruit load affects bud fate, and therefore development and metabolism, a relatively long time before the flowering induction period. Results shed light on some of the metabolic and regulatory processes that are altered in ON and OFF buds. PMID:23071667
Alternate bearing in citrus: changes in the expression of flowering control genes and in global gene expression in ON- versus OFF-crop trees.

PubMed

Shalom, Liron; Samuels, Sivan; Zur, Naftali; Shlizerman, Lyudmila; Zemach, Hanita; Weissberg, Mira; Ophir, Ron; Blumwald, Eduardo; Sadka, Avi

2012-01-01

Alternate bearing (AB) is the process in fruit trees by which cycles of heavy yield (ON crop) one year are followed by a light yield (OFF crop) the next. Heavy yield usually reduces flowering intensity the following year. Despite its agricultural importance, how the developing crop influences the following year's return bloom and yield is not fully understood. It might be assumed that an 'AB signal' is generated in the fruit, or in another organ that senses fruit presence, and moves into the bud to determine its fate-flowering or vegetative growth. The bud then responds to fruit presence by altering regulatory and metabolic pathways. Determining these pathways, and when they are altered, might indicate the nature of this putative AB signal. We studied bud morphology, the expression of flowering control genes, and global gene expression in ON- and OFF-crop buds. In May, shortly after flowering and fruit set, OFF-crop buds were already significantly longer than ON-crop buds. The number of differentially expressed genes was higher in May than at the other tested time points. Processes differentially expressed between ON- and OFF-crop trees included key metabolic and regulatory pathways, such as photosynthesis and secondary metabolism. The expression of genes of trehalose metabolism and flavonoid metabolism was validated by nCounter technology, and the latter was confirmed by metabolomic analysis. Among genes induced in OFF-crop trees was one homologous to SQUAMOSA PROMOTER BINDING-LIKE (SPL), which controls juvenile-to-adult and annual phase transitions, regulated by miR156. The expression pattern of SPL-like, miR156 and other flowering control genes suggested that fruit load affects bud fate, and therefore development and metabolism, a relatively long time before the flowering induction period. Results shed light on some of the metabolic and regulatory processes that are altered in ON and OFF buds.
Seasonal temperatures have more influence than nitrogen fertilizer rates on cucumber yield and nitrogen uptake in a double cropping system.

PubMed

Guo, Ruiying; Li, Xiaolin; Christie, Peter; Chen, Qing; Zhang, Fusuo

2008-02-01

Two-year greenhouse cucumber experiments were conducted to investigate seasonal effects on fruit yield, dry matter allocation, and N uptake in a double-cropping system with different fertilizer management. Seasonal effects were much greater than fertilizer effects, and winter-spring (WS) cucumber attained higher fruit yields and N uptake than autumn-winter (AW) cucumber due to lower cumulative air temperatures during fruit maturation in the AW season. Fertilizer N application and apparent N loss under recommended N management (Nmr) decreased by 40-78% and 33-48% without yield loss compared to conventional N management (Nmt) over four growing seasons. However, there were no seasonal differences in N recommendations, taking into consideration seasonal differences in crop N demand, critical nutrient supply in the root zone and N mineralization rate.
A fluorimetric study of the thorium-morin system

USGS Publications Warehouse

Milkey, R.G.; Fletcher, M.H.

1957-01-01

Thorium reacts with morin to yield a yellow complex that fluoresces when irradiated with ultraviolet light. The effect on the fluorescence of such variables as concentration of acid, alcohol, thorium, morin, and complex; time, temperature and wave length of exciting light are studied to determine experimental conditions yielding maximum fluorescence. The effects of Zr+4, Al+3, Fe+3, Ca+2 and La+3 are discussed. The fundamental relationships between light absorption and fluorescence are expressed in a general equation that applies to a three-component system when the fluorescence is measured in a transmission-type fluorimeter. This general equation is used to obtain an expression for the fluorescence of the thoriummorin system. Equations, derived from experimental data, relate both the fraction of thorium reacted to form complex and the fraction of unquenched fluorescence to the concentration of uncombined morin. These functions, when combined with the general equation, give an expression whichrelates the total net fluorescence to the amount of uncombined morin in the solution. This last equation can be used to determine the one region for the concentration of uncombined morin that gives maximum sensitivity for the system. Calculated standard curves are in good agreement with experimental curves.
FPGA-accelerated algorithm for the regular expression matching system

NASA Astrophysics Data System (ADS)

Russek, P.; Wiatr, K.

2015-01-01

This article describes an algorithm to support a regular expressions matching system. The goal was to achieve an attractive performance system with low energy consumption. The basic idea of the algorithm comes from a concept of the Bloom filter. It starts from the extraction of static sub-strings for strings of regular expressions. The algorithm is devised to gain from its decomposition into parts which are intended to be executed by custom hardware and the central processing unit (CPU). The pipelined custom processor architecture is proposed and a software algorithm explained accordingly. The software part of the algorithm was coded in C and runs on a processor from the ARM family. The hardware architecture was described in VHDL and implemented in field programmable gate array (FPGA). The performance results and required resources of the above experiments are given. An example of target application for the presented solution is computer and network security systems. The idea was tested on nearly 100,000 body-based viruses from the ClamAV virus database. The solution is intended for the emerging technology of clusters of low-energy computing nodes.
The combination of plant translational enhancers and terminator increase the expression of human glucocerebrosidase in Nicotiana benthamiana plants.

PubMed

Limkul, Juthamard; Misaki, Ryo; Kato, Ko; Fujiyama, Kazuhito

2015-11-01

Gaucher's disease is a lysosomal storage disorder caused by mutations in the gene encoding glucocerebrosidase (GCase). It is currently treated by enzyme replacement therapy using recombinant GCase expressed in mammalian cells. Plant production systems are among the most attractive alternatives for pharmaceutical protein production due to such advantages as low-cost, high-scalability, and safety from human pathogen contamination. Because of its high biomass yield, Nicotiana benthamiana could be an economical recombinant GCase production system. In this study, a translational enhancer and suitable terminator were utilized to obtain a powerful expression system for GCase production in N. benthamiana plants. Six plasmid constructs were used. The highest activity of 44.5units/mg protein (after subtraction of endogenous glucosidase activity of the wild-type plant) was observed in transgenic plants transformed with pAt-GC-HSP combined with a 5' untranslated region of the Arabidopsis alcohol dehydrogenase gene with the Arabidopsis heat shock protein terminator. These transgenic plant lines could pave the way to a stable plant-production system for low-cost, high-yield human GCase production. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
A triplex ribozyme expression system based on a single hairpin ribozyme.

PubMed

Aquino-Jarquin, Guillermo; Benítez-Hess, María Luisa; DiPaolo, Joseph A; Alvarez-Salas, Luis M

2008-09-01

Triplex ribozyme (RZ) configurations allow for the individual activity of trans-acting RZs in multiple expression cassettes (multiplex), thereby increasing target cleavage relative to conventionally expressed RZs. Although hairpin RZs have been advantageously compared to hammerhead RZs, their longer size and structural features complicated triplex design. We present a triplex expression system based on a single hairpin RZ with transcleavage capability and simple engineering. The system was tested in vitro using cis- and trans-cleavage kinetic assays against a known target RNA from HPV-16 E6/E7 mRNA. Single and multiplex triplex RZ constructs were more efficient in cleaving the target than tandem-cloned hairpin RZs, suggesting that the release of individual RZs enhanced trans-cleavage kinetics. Multiplex systems constructed with two different hairpin RZs resulted in better trans-cleavage compared to standard double-RZ constructs. In addition, the triplex RZ performed cis- and trans-cleavage in cervical cancer cells. The use of triplex configurations with multiplex RZs permit differential targeting of the same or different RNA, thus improving potential use against unstable targets. This prototype will provide the basis for the development of future RZ-based therapies and technologies.
Climate Change Impact on Rainfall: How will Threaten Wheat Yield?

NASA Astrophysics Data System (ADS)

Tafoughalti, K.; El Faleh, E. M.; Moujahid, Y.; Ouargaga, F.

2018-05-01

Climate change has a significant impact on the environmental condition of the agricultural region. Meknes has an agrarian economy and wheat production is of paramount importance. As most arable area are under rainfed system, Meknes is one of the sensitive regions to rainfall variability and consequently to climate change. Therefore, the use of changes in rainfall is vital for detecting the influence of climate system on agricultural productivity. This article identifies rainfall temporal variability and its impact on wheat yields. We used monthly rainfall records for three decades and wheat yields records of fifteen years. Rainfall variability is assessed utilizing the precipitation concentration index and the variation coefficient. The association between wheat yields and cumulative rainfall amounts of different scales was calculated based on a regression model. The analysis shown moderate seasonal and irregular annual rainfall distribution. Yields fluctuated from 210 to 4500 Kg/ha with 52% of coefficient of variation. The correlation results shows that wheat yields are strongly correlated with rainfall of the period January to March. This investigation concluded that climate change is altering wheat yield and it is crucial to adept the necessary adaptation to challenge the risk.

Combinatorial Screening for Transgenic Yeasts with High Cellulase Activities in Combination with a Tunable Expression System

PubMed Central

Ito, Yoichiro; Yamanishi, Mamoru; Ikeuchi, Akinori; Imamura, Chie; Matsuyama, Takashi

2015-01-01

Combinatorial screening used together with a broad library of gene expression cassettes is expected to produce a powerful tool for the optimization of the simultaneous expression of multiple enzymes. Recently, we proposed a highly tunable protein expression system that utilized multiple genome-integrated target genes to fine-tune enzyme expression in yeast cells. This tunable system included a library of expression cassettes each composed of three gene-expression control elements that in different combinations produced a wide range of protein expression levels. In this study, four gene expression cassettes with graded protein expression levels were applied to the expression of three cellulases: cellobiohydrolase 1, cellobiohydrolase 2, and endoglucanase 2. After combinatorial screening for transgenic yeasts simultaneously secreting these three cellulases, we obtained strains with higher cellulase expressions than a strain harboring three cellulase-expression constructs within one high-performance gene expression cassette. These results show that our method will be of broad use throughout the field of metabolic engineering. PMID:26692026
Goose parvovirus structural proteins expressed by recombinant baculoviruses self-assemble into virus-like particles with strong immunogenicity in goose

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

Ju, Huanyu; Wei, Na; Wang, Qian

Highlights: {yields} All three capsid proteins can be expressed in insect cells in baculovirus expression system. {yields} All three recombinant proteins were spontaneously self-assemble into virus-like particles whose size and appearance were similar to those of native purified GPV virions. {yields} The immunogenicity of GPV-VLPs was better than commercial inactivated vaccine and attenuated vaccine. -- Abstract: Goose parvovirus (GPV), a small non-enveloped ssDNA virus, can cause Derzsy's disease, and three capsid proteins of VP1, VP2, and VP3 are encoded by an overlapping nucleotide sequence. However, little is known on whether recombinant viral proteins (VPs) could spontaneously assemble into virus-like particlesmore » (VLPs) in insect cells and whether these VLPs could retain their immunoreactivity and immunogenicity in susceptible geese. To address these issues, genes for these GPV VPs were amplified by PCR, and the recombinant VPs proteins were expressed in insect cells using a baculovirus expression system for the characterization of their structures, immunoreactivity, and immunogenicity. The rVP1, rVP2, and rVP3 expressed in Sf9 cells were detected by anti-GPV sera, anti-VP3 sera, and anti-His antibodies, respectively. Electron microscopy revealed that these rVPs spontaneously assembled into VLPs in insect cells, similar to that of the purified wild-type GPV virions. In addition, vaccination with individual types of VLPs, particularly with the rVP2-VLPs, induced higher titers of antibodies and neutralized different strains of GPVs in primary goose and duck embryo fibroblast cells in vitro. These data indicated that these VLPs retained immunoreactivity and had strong immunogenicity in susceptible geese. Therefore, our findings may provide a framework for development of new vaccines for the prevention of Derzsy's disease and vehicles for the delivery of drugs.« less
The buffer value of groundwater when well yield is limited

NASA Astrophysics Data System (ADS)

Foster, T.; Brozović, N.; Speir, C.

2017-04-01

A large proportion of the total value of groundwater in conjunctive use systems is associated with the ability to smooth out shortfalls in surface water supply during droughts. Previous research has argued that aquifer depletion in these regions will impact farmers negatively by reducing the available stock of groundwater to buffer production in future periods, and also by increasing the costs of groundwater extraction. However, existing studies have not considered how depletion may impact the productivity of groundwater stocks in conjunctive use systems through reductions in well yields. In this work, we develop a hydro-economic modeling framework to quantify the effects of changes in well yields on the buffer value of groundwater, and apply this model to an illustrative case study of tomato production in California's Central Valley. Our findings demonstrate that farmers with low well yields are forced to forgo significant production and profits because instantaneous groundwater supply is insufficient to buffer surface water shortfalls in drought years. Negative economic impacts of low well yields are an increasing function of surface water variability, and are also greatest for farmers operating less efficient irrigation systems. These results indicate that impacts of well yield reductions on the productivity of groundwater are an important economic impact of aquifer depletion, and that failure to consider this feedback may lead to significant errors in estimates of the value of groundwater management in conjunctive use systems.
Generation of recombinant rotaviruses expressing fluorescent proteins using an optimized reverse genetics system.

PubMed

Komoto, Satoshi; Fukuda, Saori; Ide, Tomihiko; Ito, Naoto; Sugiyama, Makoto; Yoshikawa, Tetsushi; Murata, Takayuki; Taniguchi, Koki

2018-04-18

An entirely plasmid-based reverse genetics system for rotaviruses was established very recently. We improved the reverse genetics system to generate recombinant rotavirus by transfecting only 11 cDNA plasmids for its 11 gene segments under the condition of increasing the ratio of the cDNA plasmids for NSP2 and NSP5 genes. Utilizing this highly efficient system, we then engineered infectious recombinant rotaviruses expressing bioluminescent (NanoLuc luciferase) and fluorescent (EGFP and mCherry) reporters. These recombinant rotaviruses expressing reporters remained genetically stable during serial passages. Our reverse genetics approach and recombinant rotaviruses carrying reporter genes will be great additions to the tool kit for studying the molecular virology of rotavirus, and for developing future next-generation vaccines and expression vectors. IMPORTANCE Rotavirus is one of the most important pathogens causing severe gastroenteritis in young children worldwide. In this paper, we describe a robust and simple reverse genetics system based on only rotavirus cDNAs, and its application for engineering infectious recombinant rotaviruses harboring bioluminescent (NanoLuc) and fluorescent (EGFP and mCherry) protein genes. This highly efficient reverse genetics system and recombinant RVAs expressing reporters could be powerful tools for the study of different aspects of rotavirus replication. Furthermore, they may be useful for next-generation vaccine production for this medically important virus. Copyright © 2018 American Society for Microbiology.
A plasmid-based Escherichia coli gene expression system with cell-to-cell variation below the extrinsic noise limit

PubMed Central

2017-01-01

Experiments in synthetic biology and microbiology can benefit from protein expression systems with low cell-to-cell variability (noise) and expression levels precisely tunable across a useful dynamic range. Despite advances in understanding the molecular biology of microbial gene regulation, many experiments employ protein-expression systems exhibiting high noise and nearly all-or-none responses to induction. I present an expression system that incorporates elements known to reduce gene expression noise: negative autoregulation and bicistronic transcription. I show by stochastic simulation that while negative autoregulation can produce a more gradual response to induction, bicistronic expression of a repressor and gene of interest can be necessary to reduce noise below the extrinsic limit. I synthesized a plasmid-based system incorporating these principles and studied its properties in Escherichia coli cells, using flow cytometry and fluorescence microscopy to characterize induction dose-response, induction/repression kinetics and gene expression noise. By varying ribosome binding site strengths, expression levels from 55–10,740 molecules/cell were achieved with noise below the extrinsic limit. Individual strains are inducible across a dynamic range greater than 20-fold. Experimental comparison of different regulatory networks confirmed that bicistronic autoregulation reduces noise, and revealed unexpectedly high noise for a conventional expression system with a constitutively expressed transcriptional repressor. I suggest a hybrid, low-noise expression system to increase the dynamic range. PMID:29084263
A tetracycline expression system in combination with Sox9 for cartilage tissue engineering.

PubMed

Yao, Yi; He, Yu; Guan, Qian; Wu, Qiong

2014-02-01

Cartilage tissue engineering using controllable transcriptional therapy together with synthetic biopolymer scaffolds shows higher potential for overcoming chondrocyte degradation and constructing artificial cartilages both in vivo and in vitro. Here, the potential regulating tetracycline expression (Tet-on) system was used to express Sox9 both in vivo and in vitro. Chondrocyte degradation was measured in vitro and overcome by Soxf9 expression. Experiments confirmed the feasibility of the combined use of Sox9 and Tet-on system in cartilage tissue engineering. Engineered poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) scaffolds were seeded with recombinant chondrocytes which were transfected with Tet-induced Sox9 expression; the scaffolds were implanted under the skin of 8-week-old rats. The experimental group was injected with Dox in the abdomen, while the control group was injected with normal saline. After 4 or 8 days of implantation in vivo, the newly formed pieces of articular chondrocytes were taken out and measured. Dox injection in vivo showed positive effect on recombinant chondrocytes, in which Sox9 expression was up-regulated by an inducible system with specific matrix proteins. The results demonstrate this controllable transcriptional therapy is a potential approach for tissue engineering. Copyright © 2013 Elsevier Ltd. All rights reserved.
Trade-offs between high yields and greenhouse gas emissions in irrigation wheat cropland in China

NASA Astrophysics Data System (ADS)

Cui, Z. L.; Wu, L.; Ye, Y. L.; Ma, W. Q.; Chen, X. P.; Zhang, F. S.

2014-04-01

Although the concept of producing higher yields with reduced greenhouse gas (GHG) emissions is a goal that attracts increasing public and scientific attention, the trade-off between high yields and GHG emissions in intensive agricultural production is not well understood. Here, we hypothesize that there exists a mechanistic relationship between wheat grain yield and GHG emission, and that could be transformed into better agronomic management. A total 33 sites of on-farm experiments were investigated to evaluate the relationship between grain yield and GHG emissions using two systems (conventional practice, CP; high-yielding systems, HY) of intensive winter wheat (Triticum aestivum L.) in China. Furthermore, we discussed the potential to produce higher yields with lower GHG emissions based on a survey of 2938 farmers. Compared to the CP system, grain yield was 39% (2352 kg ha-1) higher in the HY system, while GHG emissions increased by only 10%, and GHG emission intensity was reduced by 21%. The current intensive winter wheat system with farmers' practice had a median yield and maximum GHG emission rate of 6050 kg ha-1 and 4783 kg CO2 eq ha-1, respectively; however, this system can be transformed to maintain yields while reducing GHG emissions by 26% (6077 kg ha-1, and 3555 kg CO2 eq ha-1). Further, the HY system was found to increase grain yield by 39% with a simultaneous reduction in GHG emissions by 18% (8429 kg ha-1, and 3905 kg CO2 eq ha-1, respectively). In the future, we suggest moving the trade-off relationships and calculations from grain yield and GHG emissions to new measures of productivity and environmental protection using innovative management technologies.
Effect of a free-range raising system on growth performance, carcass yield, and meat quality of slow-growing chicken.

PubMed

Wang, K H; Shi, S R; Dou, T C; Sun, H J

2009-10-01

Experiments were conducted to evaluate the effect of free-range raising systems on growth performance, carcass yield, and meat quality of slow-growing chickens. Slow-growing female chickens, Gushi chickens, were selected as the experimental birds. Two hundred 1-d-old female chicks were raised in a pen for 35 d. On d 36, ninety healthy birds, with similar BW (353.7+/-32.1g), were selected and randomly assigned to 2 treatments (indoor treatment and free-range treatment, P>0.05). Each treatment was represented by 3 groups containing 15 birds (45 birds per treatment). During the indoor treatment, the chickens were raised in floor pens in a conventional poultry research house (7 birds/m2). In the free-range treatment, the chickens were housed in a similar indoor house (7 birds/m2); in addition, they also had a free-range grass paddock (1 bird/m2). All birds were provided with the same starter and finisher diets and were raised for 112 d. Results showed that the BW and weight gain of the chickens in the free-range treatment were much lower than that of the chickens in the indoor floor treatments (P<0.05). There was no effect of the free-range raising system on eviscerated carcass, breast, thigh, and wing yield (P>0.05). However, the abdominal fat yield and tibia strength (P<0.05) significantly declined. The nutrient composition (water, protein, and fat), water-holding capacity, shear force, and pH of the muscle were largely unaffected (P>0.05) by the free-range raising system. The data indicated that the free-range raising system could significantly reduce growth performance, abdominal fat, and tibia strength, but with no effect on carcass traits and meat quality in slow-growing chickens.
Improving membrane protein expression by optimizing integration efficiency

PubMed Central

2017-01-01

The heterologous overexpression of integral membrane proteins in Escherichia coli often yields insufficient quantities of purifiable protein for applications of interest. The current study leverages a recently demonstrated link between co-translational membrane integration efficiency and protein expression levels to predict protein sequence modifications that improve expression. Membrane integration efficiencies, obtained using a coarse-grained simulation approach, robustly predicted effects on expression of the integral membrane protein TatC for a set of 140 sequence modifications, including loop-swap chimeras and single-residue mutations distributed throughout the protein sequence. Mutations that improve simulated integration efficiency were 4-fold enriched with respect to improved experimentally observed expression levels. Furthermore, the effects of double mutations on both simulated integration efficiency and experimentally observed expression levels were cumulative and largely independent, suggesting that multiple mutations can be introduced to yield higher levels of purifiable protein. This work provides a foundation for a general method for the rational overexpression of integral membrane proteins based on computationally simulated membrane integration efficiencies. PMID:28918393
Modulating secretory pathway pH by proton channel co-expression can increase recombinant protein stability in plants.

PubMed

Jutras, Philippe V; D'Aoust, Marc-André; Couture, Manon M-J; Vézina, Louis-Philippe; Goulet, Marie-Claire; Michaud, Dominique; Sainsbury, Frank

2015-09-01

Eukaryotic expression systems are used for the production of complex secreted proteins. However, recombinant proteins face considerable biochemical challenges along the secretory pathway, including proteolysis and pH variation between organelles. As the use of synthetic biology matures into solutions for protein production, various host-cell engineering approaches are being developed to ameliorate host-cell factors that can limit recombinant protein quality and yield. We report the potential of the influenza M2 ion channel as a novel tool to neutralize the pH in acidic subcellular compartments. Using transient expression in the plant host, Nicotiana benthamiana, we show that ion channel expression can significantly raise pH in the Golgi apparatus and that this can have a strong stabilizing effect on a fusion protein separated by an acid-susceptible linker peptide. We exemplify the utility of this effect in recombinant protein production using influenza hemagglutinin subtypes differentially stable at low pH; the expression of hemagglutinins prone to conformational change in mildly acidic conditions is considerably enhanced by M2 co-expression. The co-expression of a heterologous ion channel to stabilize acid-labile proteins and peptides represents a novel approach to increasing the yield and quality of secreted recombinant proteins in plants and, possibly, in other eukaryotic expression hosts. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Modelling Pasture-based Automatic Milking System Herds: The Impact of Large Herd on Milk Yield and Economics.

PubMed

Islam, M R; Clark, C E F; Garcia, S C; Kerrisk, K L

2015-07-01

The aim of this modelling study was to investigate the effect of large herd size (and land areas) on walking distances and milking interval (MI), and their impact on milk yield and economic penalties when 50% of the total diets were provided from home grown feed either as pasture or grazeable complementary forage rotation (CFR) in an automatic milking system (AMS). Twelve scenarios consisting of 3 AMS herds (400, 600, 800 cows), 2 levels of pasture utilisation (current AMS utilisation of 15.0 t dry matter [DM]/ha, termed as 'moderate'; optimum pasture utilisation of 19.7 t DM/ha, termed as 'high') and 2 rates of incorporation of grazeable complementary forage system (CFS: 0, 30%; CFS = 65% farm is CFR and 35% of farm is pasture) were investigated. Walking distances, energy loss due to walking, MI, reduction in milk yield and income loss were calculated for each treatment based on information available in the literature. With moderate pasture utilisation and 0% CFR, increasing the herd size from 400 to 800 cows resulted in an increase in total walking distances between the parlour and the paddock from 3.5 to 6.3 km. Consequently, MI increased from 15.2 to 16.4 h with increased herd size from 400 to 800 cows. High pasture utilisation (allowing for an increased stocking density) reduced the total walking distances up to 1 km, thus reduced the MI by up to 0.5 h compared to the moderate pasture, 800 cow herd combination. The high pasture utilisation combined with 30% of the farm in CFR in the farm reduced the total walking distances by up to 1.7 km and MI by up to 0.8 h compared to the moderate pasture and 800 cow herd combination. For moderate pasture utilisation, increasing the herd size from 400 to 800 cows resulted in more dramatic milk yield penalty as yield increasing from c.f. 2.6 and 5.1 kg/cow/d respectively, which incurred a loss of up to $AU 1.9/cow/d. Milk yield losses of 0.61 kg and 0.25 kg for every km increase in total walking distance (voluntary return
Tetracycline-inducible system for regulation of skeletal muscle-specific gene expression in transgenic mice

NASA Technical Reports Server (NTRS)

Grill, Mischala A.; Bales, Mark A.; Fought, Amber N.; Rosburg, Kristopher C.; Munger, Stephanie J.; Antin, Parker B.

2003-01-01

Tightly regulated control of over-expression is often necessary to study one aspect or time point of gene function and, in transgenesis, may help to avoid lethal effects and complications caused by ubiquitous over-expression. We have utilized the benefits of an optimized tet-on system and a modified muscle creatine kinase (MCK) promoter to generate a skeletal muscle-specific, doxycycline (Dox) controlled over-expression system in transgenic mice. A DNA construct was generated in which the codon optimized reverse tetracycline transactivator (rtTA) was placed under control of a skeletal muscle-specific version of the mouse MCK promoter. Transgenic mice containing this construct expressed rtTA almost exclusively in skeletal muscles. These mice were crossed to a second transgenic line containing a bi-directional promoter centered on a tet responder element driving both a luciferase reporter gene and a tagged gene of interest; in this case the calpain inhibitor calpastatin. Compound hemizygous mice showed high level, Dox dependent muscle-specific luciferase activity often exceeding 10,000-fold over non-muscle tissues of the same mouse. Western and immunocytochemical analysis demonstrated similar Dox dependent muscle-specific induction of the tagged calpastatin protein. These findings demonstrate the effectiveness and flexibility of the tet-on system to provide a tightly regulated over-expression system in adult skeletal muscle. The MCKrtTA transgenic lines can be combined with other transgenic responder lines for skeletal muscle-specific over-expression of any target gene of interest.
Analytical expressions for the evolution of many-body quantum systems quenched far from equilibrium

NASA Astrophysics Data System (ADS)

Santos, Lea F.; Torres-Herrera, E. Jonathan

2017-12-01

Possible strategies to describe analytically the dynamics of many-body quantum systems out of equilibrium include the use of solvable models and of full random matrices. None of the two approaches represent actual realistic systems, but they serve as references for the studies of these ones. We take the second path and obtain analytical expressions for the survival probability, density imbalance, and out-of-time-ordered correlator. Using these findings, we then propose an approximate expression that matches very well numerical results for the evolution of realistic finite quantum systems that are strongly chaotic and quenched far from equilibrium. In the case of the survival probability, the expression proposed covers all different time scales, from the moment the system is taken out of equilibrium to the moment it reaches a new equilibrium. The realistic systems considered are described by one-dimensional spin-1/2 models.
Cooperative working of bacterial chromosome replication proteins generated by a reconstituted protein expression system

PubMed Central

Fujiwara, Kei; Katayama, Tsutomu; Nomura, Shin-ichiro M.

2013-01-01

Replication of all living cells relies on the multirounds flow of the central dogma. Especially, expression of DNA replication proteins is a key step to circulate the processes of the central dogma. Here we achieved the entire sequential transcription–translation–replication process by autonomous expression of chromosomal DNA replication machineries from a reconstituted transcription–translation system (PURE system). We found that low temperature is essential to express a complex protein, DNA polymerase III, in a single tube using the PURE system. Addition of the 13 genes, encoding initiator, DNA helicase, helicase loader, RNA primase and DNA polymerase III to the PURE system gave rise to a DNA replication system by a coupling manner. An artificial genetic circuit demonstrated that the DNA produced as a result of the replication is able to provide genetic information for proteins, indicating the in vitro central dogma can sequentially undergo two rounds. PMID:23737447
Quantifying Soiling Loss Directly From PV Yield

DOE PAGES

Deceglie, Michael G.; Micheli, Leonardo; Muller, Matthew

2018-01-23

Soiling of photovoltaic (PV) panels is typically quantified through the use of specialized sensors. Here, we describe and validate a method for estimating soiling loss experienced by PV systems directly from system yield without the need for precipitation data. The method, termed the stochastic rate and recovery (SRR) method, automatically detects soiling intervals in a dataset, then stochastically generates a sample of possible soiling profiles based on the observed characteristics of each interval. In this paper, we describe the method, validate it against soiling station measurements, and compare it with other PV-yield-based soiling estimation methods. The broader application of themore » SRR method will enable the fleet scale assessment of soiling loss to facilitate mitigation planning and risk assessment.« less
Quantifying Soiling Loss Directly From PV Yield

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

Deceglie, Michael G.; Micheli, Leonardo; Muller, Matthew

Soiling of photovoltaic (PV) panels is typically quantified through the use of specialized sensors. Here, we describe and validate a method for estimating soiling loss experienced by PV systems directly from system yield without the need for precipitation data. The method, termed the stochastic rate and recovery (SRR) method, automatically detects soiling intervals in a dataset, then stochastically generates a sample of possible soiling profiles based on the observed characteristics of each interval. In this paper, we describe the method, validate it against soiling station measurements, and compare it with other PV-yield-based soiling estimation methods. The broader application of themore » SRR method will enable the fleet scale assessment of soiling loss to facilitate mitigation planning and risk assessment.« less
Expression, Identification and Purification of Dictyostelium Acetoacetyl-CoA Thiolase Expressed in Escherichia coli

PubMed Central

Tanaka, Takeshi; Shima, Yasuyuki; Ogawa, Naoki; Nagayama, Koki; Yoshida, Takashi; Ohmachi, Tetsuo

2011-01-01

Acetoacetyl-CoA thiolase (AT) is an enzyme that catalyses the CoA-dependent thiolytic cleavage of acetoacetyl-CoA to yield 2 molecules of acetyl-CoA, or the reverse condensation reaction. A full-length cDNA clone pBSGT-3, which has homology to known thiolases, was isolated from Dictyostelium cDNA library. Expression of the protein encoded in pBSGT-3 in Escherichia coli, its thiolase enzyme activity, and the amino acid sequence homology search revealed that pBSGT-3 encodes an AT. The recombinant AT (r-thiolase) was expressed in an active form in an E. coli expression system, and purified to homogeneity by selective ammonium sulfate fractionation and two steps of column chromatography. The purified enzyme exhibited a specific activity of 4.70 mU/mg protein. Its N-terminal sequence was (NH2)-Arg-Met-Tyr-Thr-Thr-Ala-Lys-Asn-Leu-Glu-, which corresponds to the sequence from positions 15 to 24 of the amino acid sequence deduced from pBSGT-3 clone. The r-thiolase in the inclusion body expressed highly in E. coli was the precursor form, which is slightly larger than the purified r-thiolase. When incubated with the cell-free extract of Dictyostelium cells, the precursor was converted to the same size to the purified r-thiolase, suggesting that the presequence at the N-terminus is removed by a Dictyostelium processing peptidase. PMID:21209787
Satellite-based assessment of grassland yields

NASA Astrophysics Data System (ADS)

Grant, K.; Siegmund, R.; Wagner, M.; Hartmann, S.

2015-04-01

Cutting date and frequency are important parameters determining grassland yields in addition to the effects of weather, soil conditions, plant composition and fertilisation. Because accurate and area-wide data of grassland yields are currently not available, cutting frequency can be used to estimate yields. In this project, a method to detect cutting dates via surface changes in radar images is developed. The combination of this method with a grassland yield model will result in more reliable and regional-wide numbers of grassland yields. For the test-phase of the monitoring project, a study area situated southeast of Munich, Germany, was chosen due to its high density of managed grassland. For determining grassland cutting robust amplitude change detection techniques are used evaluating radar amplitude or backscatter statistics before and after the cutting event. CosmoSkyMed and Sentinel-1A data were analysed. All detected cuts were verified according to in-situ measurements recorded in a GIS database. Although the SAR systems had various acquisition geometries, the amount of detected grassland cut was quite similar. Of 154 tested grassland plots, covering in total 436 ha, 116 and 111 cuts were detected using CosmoSkyMed and Sentinel-1A radar data, respectively. Further improvement of radar data processes as well as additional analyses with higher sample number and wider land surface coverage will follow for optimisation of the method and for validation and generalisation of the results of this feasibility study. The automation of this method will than allow for an area-wide and cost efficient cutting date detection service improving grassland yield models.
Prediction of the Dynamic Yield Strength of Metals Using Two Structural-Temporal Parameters

NASA Astrophysics Data System (ADS)

Selyutina, N. S.; Petrov, Yu. V.

2018-02-01

The behavior of the yield strength of steel and a number of aluminum alloys is investigated in a wide range of strain rates, based on the incubation time criterion of yield and the empirical models of Johnson-Cook and Cowper-Symonds. In this paper, expressions for the parameters of the empirical models are derived through the characteristics of the incubation time criterion; a satisfactory agreement of these data and experimental results is obtained. The parameters of the empirical models can depend on some strain rate. The independence of the characteristics of the incubation time criterion of yield from the loading history and their connection with the structural and temporal features of the plastic deformation process give advantage of the approach based on the concept of incubation time with respect to empirical models and an effective and convenient equation for determining the yield strength in a wider range of strain rates.
Regulatory systems for hypoxia-inducible gene expression in ischemic heart disease gene therapy.

PubMed

Kim, Hyun Ah; Rhim, Taiyoun; Lee, Minhyung

2011-07-18

Ischemic heart diseases are caused by narrowed coronary arteries that decrease the blood supply to the myocardium. In the ischemic myocardium, hypoxia-responsive genes are up-regulated by hypoxia-inducible factor-1 (HIF-1). Gene therapy for ischemic heart diseases uses genes encoding angiogenic growth factors and anti-apoptotic proteins as therapeutic genes. These genes increase blood supply into the myocardium by angiogenesis and protect cardiomyocytes from cell death. However, non-specific expression of these genes in normal tissues may be harmful, since growth factors and anti-apoptotic proteins may induce tumor growth. Therefore, tight gene regulation is required to limit gene expression to ischemic tissues, to avoid unwanted side effects. For this purpose, various gene expression strategies have been developed for ischemic-specific gene expression. Transcriptional, post-transcriptional, and post-translational regulatory strategies have been developed and evaluated in ischemic heart disease animal models. The regulatory systems can limit therapeutic gene expression to ischemic tissues and increase the efficiency of gene therapy. In this review, recent progresses in ischemic-specific gene expression systems are presented, and their applications to ischemic heart diseases are discussed. Copyright © 2011 Elsevier B.V. All rights reserved.

BRCA1 and BRCA2 expression patterns and prognostic significance in digestive system cancers.

PubMed

Wang, Gui-Hua; Zhao, Chun-Mei; Huang, Ying; Wang, Wei; Zhang, Shu; Wang, Xudong

2018-01-01

The role of BRCA1 and BRCA2 genes is mainly to maintain genome integrity in response to DNA damage through different mechanisms. Deregulation of BRCA1 and BRCA2 is associated with the development of tumor and altered sensitivity to chemotherapeutic agents. In this study, we determined protein expression of BRCA1 and BRCA2 in 4 digestive system cancers (gastric cancer, colorectal cancer, hepatocellular carcinoma, and pancreatic cancer) by immunohistochemistry on tissue microarrays. A total of 1546 samples of 4 types of cancer tissues, their matched adjacent nontumor tissues, and corresponding benign tissues were studied, respectively. Immunohistochemistry expression patterns of the 2 proteins and their correlation with patients' clinical parameters and overall survival were analyzed. The results showed that low expression of cytoplasmic BRCA1 and BRCA2 was commonly associated with advanced tumor-lymph node-metastasis stage, whereas high expression of nuclear BRCA1 was generally correlated with advanced tumor stages in these cancers. High expression of cytoplasmic BRCA1 and BRCA2 had significantly favorable overall survival in digestive system cancers; in contrast, BRCA1 nuclear expression usually predicted poor outcomes. We conclude that BRCA1 and BRCA2 could be used as clinicopathological biomarkers to evaluate the prognosis of digestive system cancers. Copyright © 2017 Elsevier Inc. All rights reserved.
Yield response to variable rate irrigation in corn

USDA-ARS?s Scientific Manuscript database

To investigate the impact of variable rate irrigation on corn yield, twenty plots of corn were laid out under a center pivot variable rate irrigation (VRI) system in an experimental field near Stoneville, MS. The VRI system is equipped with five VRI zone control units, a global positioning system (G...
Expression and purification of recombinant apolipoprotein A-I Zaragoza (L144R) and formation of reconstituted HDL particles.

PubMed

Fiddyment, Sarah; Barceló-Batllori, Sílvia; Pocoví, Miguel; García-Otín, Angel-Luis

2011-11-01

Apolipoprotein A-I Zaragoza (L144R) (apo A-I Z), has been associated with severe hypoalphalipoproteinemia and an enhanced effect of high density lipoprotein (HDL) reverse cholesterol transport. In order to perform further studies with this protein we have optimized an expression and purification method of recombinant wild-type apo A-I and apo A-I Z and produced mimetic HDL particles with each protein. An pET-45 expression system was used to produce N-terminal His-tagged apo A-I, wild-type or mutant, in Escherichia coli BL21 (DE3) which was subsequently purified by affinity chromatography in non-denaturing conditions. HDL particles were generated via a modified sodium cholate method. Expression and purification of both proteins was verified by SDS-PAGE, MALDI-TOF MS and immunochemical procedures. Yield was 30mg of purified protein (94% purity) per liter of culture. The reconstituted HDL particles checked via non-denaturing PAGE showed high homogeneity in their size when reconstituted both with wild-type apo A-I and apo A-I Z. An optimized system for the expression and purification of wild-type apo A-I and apo A-I Z with high yield and purity grade has been achieved, in addition to their use in reconstituted HDL particles, as a basis for further studies. Copyright © 2011 Elsevier Inc. All rights reserved.
Increased SBPase activity improves photosynthesis and grain yield in wheat grown in greenhouse conditions.

PubMed

Driever, Steven M; Simkin, Andrew J; Alotaibi, Saqer; Fisk, Stuart J; Madgwick, Pippa J; Sparks, Caroline A; Jones, Huw D; Lawson, Tracy; Parry, Martin A J; Raines, Christine A

2017-09-26

To meet the growing demand for food, substantial improvements in yields are needed. This is particularly the case for wheat, where global yield has stagnated in recent years. Increasing photosynthesis has been identified as a primary target to achieve yield improvements. To increase leaf photosynthesis in wheat, the level of the Calvin-Benson cycle enzyme sedoheptulose-1,7-biphosphatase (SBPase) has been increased through transformation and expression of a Brachypodium distachyon SBPase gene construct. Transgenic lines with increased SBPase protein levels and activity were grown under greenhouse conditions and showed enhanced leaf photosynthesis and increased total biomass and dry seed yield. This showed the potential of improving yield potential by increasing leaf photosynthesis in a crop species such as wheat. The results are discussed with regard to future strategies for further improvement of photosynthesis in wheat.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'. © 2017 The Authors.
Heterologous expression of proteins from Plasmodium falciparum: results from 1000 genes.

PubMed

Mehlin, Christopher; Boni, Erica; Buckner, Frederick S; Engel, Linnea; Feist, Tiffany; Gelb, Michael H; Haji, Lutfiyah; Kim, David; Liu, Colleen; Mueller, Natascha; Myler, Peter J; Reddy, J T; Sampson, Joshua N; Subramanian, E; Van Voorhis, Wesley C; Worthey, Elizabeth; Zucker, Frank; Hol, Wim G J

2006-08-01

As part of a structural genomics initiative, 1000 open reading frames from Plasmodium falciparum, the causative agent of the most deadly form of malaria, were tested in an E. coli protein expression system. Three hundred and thirty-seven of these targets were observed to express, although typically the protein was insoluble. Sixty-three of the targets provided soluble protein in yields ranging from 0.9 to 406.6 mg from one liter of rich media. Higher molecular weight, greater protein disorder (segmental analysis, SEG), more basic isoelectric point (pI), and a lack of homology to E. coli proteins were all highly and independently correlated with difficulties in expression. Surprisingly, codon usage and the percentage of adenosines and thymidines (%AT) did not appear to play a significant role. Of those proteins which expressed, high pI and a hypothetical annotation were both strongly and independently correlated with insolubility. The overwhelmingly important role of pI in both expression and solubility appears to be a surprising and fundamental issue in the heterologous expression of P. falciparum proteins in E. coli. Twelve targets which did not express in E. coli from the native gene sequence were codon-optimized through whole gene synthesis, resulting in the (insoluble) expression of three of these proteins. Seventeen targets which were expressed insolubly in E. coli were moved into a baculovirus/Sf-21 system, resulting in the soluble expression of one protein at a high level and six others at a low level. A variety of factors conspire to make the heterologous expression of P. falciparum proteins challenging, and these observations lay the groundwork for a rational approach to prioritizing and, ultimately, eliminating these impediments.
Expression profiles of inka2 in the murine nervous system.

PubMed

Iwasaki, Yumi; Yumoto, Takahito; Sakakibara, Shin-Ichi

2015-01-01

Dynamic rearrangement of the actin cytoskeleton impacts many cellular characteristics in both the developing and adult central nervous systems (CNS), including the migration and adhesion of highly motile neural progenitor cells, axon guidance of immature neurons, and reconstruction of synaptic structures in the adult brain. Inka1, a known regulator of actin cytoskeleton reconstruction, is predominantly expressed by the neural crest cell lineage and regulates the migration and differentiation of these cells. In the present study, we identified a novel gene, designated as inka2, which is related to inka1. Inka2/fam212b is an evolutionarily conserved gene found in different vertebrate species and constitutes a novel gene family together with inka1. Northern blot analysis showed that inka2 mRNA was highly enriched in the nervous system. The spatiotemporal propagation cell profiles of those cells that expressed inka2 transcripts were compatible with those of Olig2-positive oligodendrocyte progenitor cells, which originate in the ventral ventricular zone during embryogenesis. Intense expression of inka2 was also noted in the proliferative neuronal progenitors in the developing cerebellum. On the other hand, immature newborn neurons in the embryonic brain showed no expression of inka2, except for the cells residing in the marginal zone of the embryonic telencephalon, which is known to contain transient cells including the non-subplate pioneer neurons and Cajal-Retzius cells. As brain development proceeds during the postnatal stage, inka2 expression emerged in some populations of immature neurons, including the neocortical pyramidal neurons, hippocampal pyramidal neurons, and granule cells migrating in the cerebellar cortex. In the adult brain, the expression of inka2 was interestingly confined in terminally differentiated neurons in the restricted forebrain regions. Taken together, as a novel regulator of actin cytoskeletons in the CNS, inka2 may be involved in multiple
Integrated model for predicting rice yield with climate change

NASA Astrophysics Data System (ADS)

Park, Jin-Ki; Das, Amrita; Park, Jong-Hwa

2018-04-01

Rice is the chief agricultural product and one of the primary food source. For this reason, it is of pivotal importance for worldwide economy and development. Therefore, in a decision-support-system both for the farmers and in the planning and management of the country's economy, forecasting yield is vital. However, crop yield, which is a dependent of the soil-bio-atmospheric system, is difficult to represent in statistical language. This paper describes a novel approach for predicting rice yield using artificial neural network, spatial interpolation, remote sensing and GIS methods. Herein, the variation in the yield is attributed to climatic parameters and crop health, and the normalized difference vegetation index from MODIS is used as an indicator of plant health and growth. Due importance was given to scaling up the input parameters using spatial interpolation and GIS and minimising the sources of error in every step of the modelling. The low percentage error (2.91) and high correlation (0.76) signifies the robust performance of the proposed model. This simple but effective approach is then used to estimate the influence of climate change on South Korean rice production. As proposed in the RCP8.5 scenario, an upswing in temperature may increase the rice yield throughout South Korea.
An Overview and History of Glyco-Engineering in Insect Expression Systems.

PubMed

Geisler, Christoph; Mabashi-Asazuma, Hideaki; Jarvis, Donald L

2015-01-01

Insect systems, including the baculovirus-insect cell and Drosophila S2 cell systems are widely used as recombinant protein production platforms. Historically, however, no insect-based system has been able to produce glycoproteins with human-type glycans, which often influence the clinical efficacy of therapeutic glycoproteins and the overall structures and functions of other recombinant glycoprotein products. In addition, some insect cell systems produce N-glycans with immunogenic epitopes. Over the past 20 years, these problems have been addressed by efforts to glyco-engineer insect-based expression systems. These efforts have focused on introducing the capacity to produce complex-type, terminally sialylated N-glycans and eliminating the capacity to produce immunogenic N-glycans. Various glyco-engineering approaches have included genetically engineering insect cells, baculoviral vectors, and/or insects with heterologous genes encoding the enzymes required to produce various glycosyltransferases, sugars, nucleotide sugars, and nucleotide sugar transporters, as well as an enzyme that can deplete GDP-fucose. In this chapter, we present an overview and history of glyco-engineering in insect expression systems as a prelude to subsequent chapters, which will highlight various methods used for this purpose.
A constitutive expression system for glycosyl hydrolase family 7 cellobiohydrolases in Hypocrea jecorina

DOE PAGES

Linger, Jeffrey G.; Taylor, II, Larry E.; Baker, John O.; ...

2015-03-18

One of the primary industrial-scale cellulase producers is the ascomycete fungus, Hypocrea jecorina, which produces and secretes large quantities of diverse cellulolytic enzymes. Perhaps the single most important biomass degrading enzyme is cellobiohydrolase I (cbh1or Cel7A) due to its enzymatic proficiency in cellulose depolymerization. However, production of Cel7A with native-like properties from heterologous expression systems has proven difficult. In this study, we develop a protein expression system in H. jecorina (Trichoderma reesei) useful for production and secretion of heterologous cellobiohydrolases from glycosyl hydrolase family 7. Building upon previous work in heterologous protein expression in filamentous fungi, we have integrated amore » native constitutive enolase promoter with the native cbh1 signal sequence. The results are the following: The constitutive eno promoter driving the expression of Cel7A allows growth on glucose and results in repression of the native cellulase system, severely reducing background endo- and other cellulase activity and greatly simplifying purification of the recombinant protein. Coupling this system to a Δcbh1 strain of H. jecorina ensures that only the recombinant Cel7A protein is produced. Two distinct transformant colony morphologies were observed and correlated with high and null protein production. Production levels in ‘fast’ transformants are roughly equivalent to those in the native QM6a strain of H. jecorina, typically in the range of 10 to 30 mg/L when grown in continuous stirred-tank fermenters. ‘Slow’ transformants showed no evidence of Cel7A production. Specific activity of the purified recombinant Cel7A protein is equivalent to that of native protein when assayed on pretreated corn stover, as is the thermal stability and glycosylation level. Purified Cel7A produced from growth on glucose demonstrated remarkably consistent specific activity. Purified Cel7A from the same strain grown on lactose
Control of gene expression by CRISPR-Cas systems

PubMed Central

2013-01-01

Clustered regularly interspaced short palindromic repeats (CRISPR) loci and their associated cas (CRISPR-associated) genes provide adaptive immunity against viruses (phages) and other mobile genetic elements in bacteria and archaea. While most of the early work has largely been dominated by examples of CRISPR-Cas systems directing the cleavage of phage or plasmid DNA, recent studies have revealed a more complex landscape where CRISPR-Cas loci might be involved in gene regulation. In this review, we summarize the role of these loci in the regulation of gene expression as well as the recent development of synthetic gene regulation using engineered CRISPR-Cas systems. PMID:24273648
The yield and post-yield behavior of high-density polyethylene

NASA Technical Reports Server (NTRS)

Semeliss, M. A.; Wong, R.; Tuttle, M. E.

1990-01-01

An experimental and analytical evaluation was made of the yield and post-yield behavior of high-density polyethylene, a semi-crystalline thermoplastic. Polyethylene was selected for study because it is very inexpensive and readily available in the form of thin-walled tubes. Thin-walled tubular specimens were subjected to axial loads and internal pressures, such that the specimens were subjected to a known biaxial loading. A constant octahederal shear stress rate was imposed during all tests. The measured yield and post-yield behavior was compared with predictions based on both isotropic and anisotropic models. Of particular interest was whether inelastic behavior was sensitive to the hydrostatic stress level. The major achievements and conclusions reached are discussed.
Insect cells-baculovirus system for the production of difficult to express proteins.

PubMed

Osz-Papai, Judit; Radu, Laura; Abdulrahman, Wassim; Kolb-Cheynel, Isabelle; Troffer-Charlier, Nathalie; Birck, Catherine; Poterszman, Arnaud

2015-01-01

The production of sufficient quantities of homogenous protein not only is an essential prelude for structural investigations but also represents a rate-limiting step for many human functional studies. Although technologies for expression of recombinant proteins and complexes have been improved tremendously, in many cases, protein production remains a challenge and can be associated with considerable investment. This chapter describes simple and efficient protocols for expression screening and optimization of protein production in insect cells using the baculovirus expression system. We describe the procedure, starting from the cloning of a gene of interest into an expression transfer baculovirus vector, followed by generation of the recombinant virus by homologous recombination, evaluation of protein expression, and scale-up. Handling of insect cell cultures and preparation of bacmid for co-transfection are also detailed.
A Novel Tightly Regulated Gene Expression System for the Human Intestinal Symbiont Bacteroides thetaiotaomicron.

PubMed

Horn, Nikki; Carvalho, Ana L; Overweg, Karin; Wegmann, Udo; Carding, Simon R; Stentz, Régis

2016-01-01

There is considerable interest in studying the function of Bacteroides species resident in the human gastrointestinal (GI)-tract and the contribution they make to host health. Reverse genetics and protein expression techniques, such as those developed for well-characterized Escherichia coli cannot be applied to Bacteroides species as they and other members of the Bacteriodetes phylum have unique promoter structures. The availability of useful Bacteroides-specific genetic tools is therefore limited. Here we describe the development of an effective mannan-controlled gene expression system for Bacteroides thetaiotaomicron containing the mannan-inducible promoter-region of an α-1,2-mannosidase gene (BT_3784), a ribosomal binding site designed to modulate expression, a multiple cloning site to facilitate the cloning of genes of interest, and a transcriptional terminator. Using the Lactobacillus pepI as a reporter gene, mannan induction resulted in an increase of reporter activity in a time- and concentration-dependent manner with a wide range of activity. The endogenous BtcepA cephalosporinase gene was used to demonstrate the suitability of this novel expression system, enabling the isolation of a His-tagged version of BtCepA. We have also shown with experiments performed in mice that the system can be induced in vivo in the presence of an exogenous source of mannan. By enabling the controlled expression of endogenous and exogenous genes in B. thetaiotaomicron this novel inducer-dependent expression system will aid in defining the physiological role of individual genes and the functional analyses of their products.
A Novel Tightly Regulated Gene Expression System for the Human Intestinal Symbiont Bacteroides thetaiotaomicron

PubMed Central

Horn, Nikki; Carvalho, Ana L.; Overweg, Karin; Wegmann, Udo; Carding, Simon R.; Stentz, Régis

2016-01-01

There is considerable interest in studying the function of Bacteroides species resident in the human gastrointestinal (GI)-tract and the contribution they make to host health. Reverse genetics and protein expression techniques, such as those developed for well-characterized Escherichia coli cannot be applied to Bacteroides species as they and other members of the Bacteriodetes phylum have unique promoter structures. The availability of useful Bacteroides-specific genetic tools is therefore limited. Here we describe the development of an effective mannan-controlled gene expression system for Bacteroides thetaiotaomicron containing the mannan-inducible promoter–region of an α-1,2-mannosidase gene (BT_3784), a ribosomal binding site designed to modulate expression, a multiple cloning site to facilitate the cloning of genes of interest, and a transcriptional terminator. Using the Lactobacillus pepI as a reporter gene, mannan induction resulted in an increase of reporter activity in a time- and concentration-dependent manner with a wide range of activity. The endogenous BtcepA cephalosporinase gene was used to demonstrate the suitability of this novel expression system, enabling the isolation of a His-tagged version of BtCepA. We have also shown with experiments performed in mice that the system can be induced in vivo in the presence of an exogenous source of mannan. By enabling the controlled expression of endogenous and exogenous genes in B. thetaiotaomicron this novel inducer-dependent expression system will aid in defining the physiological role of individual genes and the functional analyses of their products. PMID:27468280
Rooting traits of peanut genotypes with different yield responses to terminal drought

USDA-ARS?s Scientific Manuscript database

Drought at pod filling can severely reduce yield of peanut. Better root systems can reduce yield loss from drought. However, the relationship of root characters with yield under terminal drought is not well understood. The objective of this study was to investigate the responses of peanut genotyp...
Optimizing Culture Medium Composition to Improve Oligodendrocyte Progenitor Cell Yields In Vitro from Subventricular Zone-Derived Neural Progenitor Cell Neurospheres

PubMed Central

Franco, Paula G.; Pasquini, Juana M.; Silvestroff, Lucas

2015-01-01

Neural Stem and Progenitor Cells (NSC/NPC) are gathering tangible recognition for their uses in cell therapy and cell replacement therapies for human disease, as well as a model system to continue research on overall neural developmental processes in vitro. The Subventricular Zone is one of the largest NSC/NPC niches in the developing mammalian Central Nervous System, and persists through to adulthood. Oligodendrocyte progenitor cell (OPC) enriched cultures are usefull tools for in vitro studies as well as for cell replacement therapies for treating demyelination diseases. We used Subventricular Zone-derived NSC/NPC primary cultures from newborn mice and compared the effects of different growth factor combinations on cell proliferation and OPC yield. The Platelet Derived Growth Factor-AA and BB homodimers had a positive and significant impact on OPC generation. Furthermore, heparin addition to the culture media contributed to further increase overall culture yields. The OPC generated by this protocol were able to mature into Myelin Basic Protein-expressing cells and to interact with neurons in an in vitro co-culture system. As a whole, we describe an optimized in vitro method for increasing OPC. PMID:25837625
Proteomic analysis of high yield rice variety mutated from spaceflight

NASA Astrophysics Data System (ADS)

Ma, Y.; Cheng, Z.; Wang, W.; Sun, Y.

Seeds of pure rice varieties were flown on Chinese recoverable satellite, JB-1, for a 15-day flight in 1996. Many mutant rice varieties with various phenotypes were generated after continuous selection and breeding. Among the mutants, a variety 971-5 showed a significant increase in grain yield compared to its control (971ck). In this study, proteomic analysis of both mutant variety 971-5 and control variety 971ck were carried out to investigate the changes of protein expression level in their leaves at three different growth stages (early and middle stage of tillering, and booting stage). Results showed that (1) almost all differentially expressed proteins were down-regulated in 971-5 with only one exception, (2) the percentages of differentially expressed proteins were 3.1%, 2.1% and 3.1% at the three stages, respectively, and (3) one protein showed a significant alteration in its molecular weight (MW). These data demonstrated that the space environment can alter the expression level of rice proteins both quantitatively and qualitatively.
An adapted yield criterion for the evolution of subsequent yield surfaces

NASA Astrophysics Data System (ADS)

Küsters, N.; Brosius, A.

2017-09-01

In numerical analysis of sheet metal forming processes, the anisotropic material behaviour is often modelled with isotropic work hardening and an average Lankford coefficient. In contrast, experimental observations show an evolution of the Lankford coefficients, which can be associated with a yield surface change due to kinematic and distortional hardening. Commonly, extensive efforts are carried out to describe these phenomena. In this paper an isotropic material model based on the Yld2000-2d criterion is adapted with an evolving yield exponent in order to change the yield surface shape. The yield exponent is linked to the accumulative plastic strain. This change has the effect of a rotating yield surface normal. As the normal is directly related to the Lankford coefficient, the change can be used to model the evolution of the Lankford coefficient during yielding. The paper will focus on the numerical implementation of the adapted material model for the FE-code LS-Dyna, mpi-version R7.1.2-d. A recently introduced identification scheme [1] is used to obtain the parameters for the evolving yield surface and will be briefly described for the proposed model. The suitability for numerical analysis will be discussed for deep drawing processes in general. Efforts for material characterization and modelling will be compared to other common yield surface descriptions. Besides experimental efforts and achieved accuracy, the potential of flexibility in material models and the risk of ambiguity during identification are of major interest in this paper.
Deregulated HOXB7 expression predicts poor prognosis of patients with malignancies of digestive system.

PubMed

Liu, Fang-Teng; Chen, Han-Min; Xiong, Ying; Zhu, Zheng-Ming

2017-07-26

Numerous studies have investigated the relationship between deregulated HOXB7 expression with the clinical outcome in patients with digestive stem cancers, HOXB7 has showed negative impacts but with varying levels. We aimed to comprehensively evaluate the prediction and prognostic value of HOXB7 in digestive stem cancers. Electronic databases updated to December 1, 2016 were retrieved to collect relevant eligible studies to quantitatively explore the potential roles of HOXB7 as a prognostic indicator in digestive system cancers. A total of 9 studies (n = 1298 patients) was included in this synthetical meta-analysis. The pooled hazard ratios suggested that high expression of HOXB7 protein was associated with poor prognosis of OS in patients with digestive system cancers (HR = 1.97, 95% CI: 1.65-2.28, p= 0.000), and HOXB7 protein could act as an independent prognostic factor for predicting OS of patients with digestive system cancers (HR: 2.02, 95% CI: 1.69-2.36, p = 0.000). Statistical significance was also observed in subgroup meta-analysis based on the cancer type, histology type, country, sample size and publication date. Furthermore, we examined the correlations between HOXB7 protein and clinicopathological features. It showed that altered expression of HOXB7 protein was correlated with tumor invasion (p = 0.000), lymph node status (p = 0.000), distant metastasis (p = 0.001) and TNM stage (p = 0.000). However, the expression of HOXB7 protein was not associated with age (p = 0.64), gender (p = 0.40) or levels of differentiation (p = 0.19). High expression of HOXB7 protein was associated with poor prognosis of patients with digestive system cancers, as well as clinicopathologic characteristics, including the tumor invasion, lymph node status, distant metastasis and TNM stage. The expression of HOXB7 protein was not associated with age, gender or levels of differentiation. HOXB7 protein expression level in tumor tissue might serve as a novel prognostic marker for
Crop monitoring & yield forecasting system based on Synthetic Aperture Radar (SAR) and process-based crop growth model: Development and validation in South and South East Asian Countries

NASA Astrophysics Data System (ADS)

Setiyono, T. D.

2014-12-01

Accurate and timely information on rice crop growth and yield helps governments and other stakeholders adapting their economic policies and enables relief organizations to better anticipate and coordinate relief efforts in the wake of a natural catastrophe. Such delivery of rice growth and yield information is made possible by regular earth observation using space-born Synthetic Aperture Radar (SAR) technology combined with crop modeling approach to estimate yield. Radar-based remote sensing is capable of observing rice vegetation growth irrespective of cloud coverage, an important feature given that in incidences of flooding the sky is often cloud-covered. The system allows rapid damage assessment over the area of interest. Rice yield monitoring is based on a crop growth simulation and SAR-derived key information, particularly start of season and leaf growth rate. Results from pilot study sites in South and South East Asian countries suggest that incorporation of SAR data into crop model improves yield estimation for actual yields. Remote-sensing data assimilation into crop model effectively capture responses of rice crops to environmental conditions over large spatial coverage, which otherwise is practically impossible to achieve. Such improvement of actual yield estimates offers practical application such as in a crop insurance program. Process-based crop simulation model is used in the system to ensure climate information is adequately captured and to enable mid-season yield forecast.

Development and characterization of a eukaryotic expression system for human type II procollagen.

PubMed

Wieczorek, Andrew; Rezaei, Naghmeh; Chan, Clara K; Xu, Chuan; Panwar, Preety; Brömme, Dieter; Merschrod S, Erika F; Forde, Nancy R

2015-12-15

Triple helical collagens are the most abundant structural protein in vertebrates and are widely used as biomaterials for a variety of applications including drug delivery and cellular and tissue engineering. In these applications, the mechanics of this hierarchically structured protein play a key role, as does its chemical composition. To facilitate investigation into how gene mutations of collagen lead to disease as well as the rational development of tunable mechanical and chemical properties of this full-length protein, production of recombinant expressed protein is required. Here, we present a human type II procollagen expression system that produces full-length procollagen utilizing a previously characterized human fibrosarcoma cell line for production. The system exploits a non-covalently linked fluorescence readout for gene expression to facilitate screening of cell lines. Biochemical and biophysical characterization of the secreted, purified protein are used to demonstrate the proper formation and function of the protein. Assays to demonstrate fidelity include proteolytic digestion, mass spectrometric sequence and posttranslational composition analysis, circular dichroism spectroscopy, single-molecule stretching with optical tweezers, atomic-force microscopy imaging of fibril assembly, and transmission electron microscopy imaging of self-assembled fibrils. Using a mammalian expression system, we produced full-length recombinant human type II procollagen. The integrity of the collagen preparation was verified by various structural and degradation assays. This system provides a platform from which to explore new directions in collagen manipulation.
Dynamics of Immune System Gene Expression upon Bacterial Challenge and Wounding in a Social Insect (Bombus terrestris)

PubMed Central

Erler, Silvio; Popp, Mario; Lattorff, H. Michael G.

2011-01-01

The innate immune system which helps individuals to combat pathogens comprises a set of genes representing four immune system pathways (Toll, Imd, JNK and JAK/STAT). There is a lack of immune genes in social insects (e.g. honeybees) when compared to Diptera. Potentially, this might be compensated by an advanced system of social immunity (synergistic action of several individuals). The bumble bee, Bombus terrestris, is a primitively eusocial species with an annual life cycle and colonies headed by a single queen. We used this key pollinator to study the temporal dynamics of immune system gene expression in response to wounding and bacterial challenge. Antimicrobial peptides (AMP) (abaecin, defensin 1, hymenoptaecin) were strongly up-regulated by wounding and bacterial challenge, the latter showing a higher impact on the gene expression level. Sterile wounding down-regulated TEP A, an effector gene of the JAK/STAT pathway, and bacterial infection influenced genes of the Imd (relish) and JNK pathway (basket). Relish was up-regulated within the first hour after bacterial challenge, but decreased strongly afterwards. AMP expression following wounding and bacterial challenge correlates with the expression pattern of relish whereas correlated expression with dorsal was absent. Although expression of AMPs was high, continuous bacterial growth was observed throughout the experiment. Here we demonstrate for the first time the temporal dynamics of immune system gene expression in a social insect. Wounding and bacterial challenge affected the innate immune system significantly. Induction of AMP expression due to wounding might comprise a pre-adaptation to accompanying bacterial infections. Compared with solitary species this social insect exhibits reduced immune system efficiency, as bacterial growth could not be inhibited. A negative feedback loop regulating the Imd-pathway is suggested. AMPs, the end product of the Imd-pathway, inhibited the up-regulation of the
Expression and functional characterisation of System L amino acid transporters in the human term placenta.

PubMed

Gaccioli, Francesca; Aye, Irving L M H; Roos, Sara; Lager, Susanne; Ramirez, Vanessa I; Kanai, Yoshikatsu; Powell, Theresa L; Jansson, Thomas

2015-06-09

System L transporters LAT1 (SLC7A5) and LAT2 (SLC7A8) mediate the uptake of large, neutral amino acids in the human placenta. Many System L substrates are essential amino acids, thus representing crucial nutrients for the growing fetus. Both LAT isoforms are expressed in the human placenta, but the relative contribution of LAT1 and LAT2 to placental System L transport and their subcellular localisation are not well established. Moreover, the influence of maternal body mass index (BMI) on placental System L amino acid transport is poorly understood. Therefore the aims of this study were to determine: i) the relative contribution of the LAT isoforms to System L transport activity in primary human trophoblast (PHT) cells isolated from term placenta; ii) the subcellular localisation of LAT transporters in human placenta; and iii) placental expression and activity of System L transporters in response to maternal overweight/obesity. System L mediated leucine uptake was measured in PHT cells after treatment with si-RNA targeting LAT1 and/or LAT2. The localisation of LAT isoforms was studied in isolated microvillous plasma membranes (MVM) and basal membranes (BM) by Western blot analysis. Results were confirmed by immunohistochemistry in sections of human term placenta. Expression and activity System L transporters was measured in isolated MVM from women with varying pre-pregnancy BMI. Both LAT1 and LAT2 isoforms contribute to System L transport activity in primary trophoblast cells from human term placenta. LAT1 and LAT2 transporters are highly expressed in the MVM of the syncytiotrophoblast layer at term. LAT2 is also localised in the basal membrane and in endothelial cells lining the fetal capillaries. Measurements in isolated MVM vesicles indicate that System L transporter expression and activity is not influenced by maternal BMI. LAT1 and LAT2 are present and functional in the syncytiotrophoblast MVM, whereas LAT2 is also expressed in the BM and in the fetal capillary
Re-directing bacterial microcompartment systems to enhance recombinant expression of lysis protein E from bacteriophage ΦX174 in Escherichia coli

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

Yung, Mimi C.; Bourguet, Feliza A.; Carpenter, Timothy S.

Recombinant expression of toxic proteins remains a challenging problem. Furthermore, one potential method to shield toxicity and thus improve expression of these proteins is to encapsulate them within protein compartments to sequester them away from their targets. Many bacteria naturally produce so-called bacterial microcompartments (BMCs) in which enzymes comprising a biosynthetic pathway are encapsulated in a proteinaeous shell, which is in part thought to shield the cells from the toxicity of reaction intermediates. As a proof-of-concept, we attempted to encapsulate toxic, lysis protein E (E) from bacteriophage ΦX174 inside recombinant BMCs to enhance its expression and achieve higher yields duringmore » downstream purification.« less
Re-directing bacterial microcompartment systems to enhance recombinant expression of lysis protein E from bacteriophage ΦX174 in Escherichia coli

DOE PAGES

Yung, Mimi C.; Bourguet, Feliza A.; Carpenter, Timothy S.; ...

2017-04-26

Recombinant expression of toxic proteins remains a challenging problem. Furthermore, one potential method to shield toxicity and thus improve expression of these proteins is to encapsulate them within protein compartments to sequester them away from their targets. Many bacteria naturally produce so-called bacterial microcompartments (BMCs) in which enzymes comprising a biosynthetic pathway are encapsulated in a proteinaeous shell, which is in part thought to shield the cells from the toxicity of reaction intermediates. As a proof-of-concept, we attempted to encapsulate toxic, lysis protein E (E) from bacteriophage ΦX174 inside recombinant BMCs to enhance its expression and achieve higher yields duringmore » downstream purification.« less
Growth, Yield and Fruit Quality of Grapevines under Organic and Biodynamic Management

PubMed Central

Döring, Johanna; Frisch, Matthias; Tittmann, Susanne; Stoll, Manfred; Kauer, Randolf

2015-01-01

The main objective of this study was to determine growth, yield and fruit quality of grapevines under organic and biodynamic management in relation to integrated viticultural practices. Furthermore, the mechanisms for the observed changes in growth, yield and fruit quality were investigated by determining nutrient status, physiological performance of the plants and disease incidence on bunches in three consecutive growing seasons. A field trial (Vitis vinifera L. cv. Riesling) was set up at Hochschule Geisenheim University, Germany. The integrated treatment was managed according to the code of good practice. Organic and biodynamic plots were managed according to Regulation (EC) No 834/2007 and Regulation (EC) No 889/2008 and according to ECOVIN- and Demeter-Standards, respectively. The growth and yield of the grapevines differed strongly among the different management systems, whereas fruit quality was not affected by the management system. The organic and the biodynamic treatments showed significantly lower growth and yield in comparison to the integrated treatment. The physiological performance was significantly lower in the organic and the biodynamic systems, which may account for differences in growth and cluster weight and might therefore induce lower yields of the respective treatments. Soil management and fertilization strategy could be responsible factors for these changes. Yields of the organic and the biodynamic treatments partially decreased due to higher disease incidence of downy mildew. The organic and the biodynamic plant protection strategies that exclude the use of synthetic fungicides are likely to induce higher disease incidence and might partially account for differences in the nutrient status of vines under organic and biodynamic management. Use of the biodynamic preparations had little influence on vine growth and yield. Due to the investigation of important parameters that induce changes especially in growth and yield of grapevines under
The Challenges of Recombinant Endostatin in Clinical Application: Focus on the Different Expression Systems and Molecular Bioengineering

PubMed Central

Mohajeri, Abbas; Sanaei, Sarvin; Kiafar, Farhad; Fattahi, Amir; Khalili, Majid; Zarghami, Nosratollah

2017-01-01

Angiogenesis plays an essential role in rapid growing and metastasis of the tumors. Inhibition of angiogenesis is a putative strategy for cancer therapy. Endostatin (Es) is an attractive anti-angiogenesis protein with some clinical application challenges including; short half-life, instability in serum and requirement to high dosage. Therefore, production of recombinant endostatin (rEs) is necessary in large scale. The production of rEs is difficult because of its structural properties and is high-cost. Therefore, this review focused on the different expression systems that involved in rEs production including; mammalian, baculovirus, yeast, and Escherichia coli (E. coli) expression systems. The evaluating of the results of different expression systems declared that none of the mentioned systems can be considered to be generally superior to the other. Meanwhile with considering the advantages and disadvantage of E. coli expression system compared with other systems beside the molecular properties of Es, E. coli expression system can be a preferred expression system for expressing of the Es in large scale. Also, the molecular bioengineering and sustained release formulations that lead to improving of its stability and bioactivity will be discussed. Point mutation (P125A) of Es, addition of RGD moiety or an additional zinc biding site to N-terminal of Es , fusing of Es to anti-HER2 IgG or heavy-chain of IgG, and finally loading of the endostar by PLGA and PEG- PLGA nanoparticles and gold nano-shell particles are the effective bioengineering methods to overcome to clinical changes of endostatin. PMID:28507934
Light-Weight Multispectral Uav Sensors and Their Capabilities for Predicting Grain Yield and Detecting Plant Diseases

NASA Astrophysics Data System (ADS)

Nebiker, S.; Lack, N.; Abächerli, M.; Läderach, S.

2016-06-01

In this paper we investigate the performance of new light-weight multispectral sensors for micro UAV and their application to selected tasks in agronomical research and agricultural practice. The investigations are based on a series of flight campaigns in 2014 and 2015 covering a number of agronomical test sites with experiments on rape, barley, onion, potato and other crops. In our sensor comparison we included a high-end multispectral multiSPEC 4C camera with bandpass colour filters and reference channel in zenith direction and a low-cost, consumer-grade Canon S110 NIR camera with Bayer pattern colour filters. Ground-based reference measurements were obtained using a terrestrial hyperspectral field spectrometer. The investigations show that measurements with the high-end system consistently match very well with ground-based field spectrometer measurements with a mean deviation of just 0.01-0.04 NDVI values. The low-cost system, while delivering better spatial resolutions, expressed significant biases. The sensors were subsequently used to address selected agronomical questions. These included crop yield estimation in rape and barley and plant disease detection in potato and onion cultivations. High levels of correlation between different vegetation indices and reference yield measurements were obtained for rape and barley. In case of barley, the NDRE index shows an average correlation of 87% with reference yield, when species are taken into account. With high geometric resolutions and respective GSDs of down to 2.5 cm the effects of a thrips infestation in onion could be analysed and potato blight was successfully detected at an early stage of infestation.
Localization of PPARdelta in murine central nervous system: expression in oligodendrocytes and neurons.

PubMed

Woods, John W; Tanen, Michael; Figueroa, David J; Biswas, Chhabi; Zycband, Emanuel; Moller, David E; Austin, Christopher P; Berger, Joel P

2003-06-13

The peroxisome proliferator-activated receptors (PPARs), PPARdelta, PPARgamma and PPARalpha, comprise a subclass of the supergene family of nuclear receptors. As such they are ligand-regulated transcription factors whose major effects are mediated by altering expression of target genes. PPARdelta has been shown to be ubiquitously expressed in mammals. However, its primary biological role(s) has yet to be defined. Several recent studies have demonstrated that PPARdelta is the most highly expressed PPAR isoform in the central nervous system, but ambiguity still exists as to the specific brain sub-regions and cells in which it is expressed. Here, utilizing novel, isoform-selective PPARdelta riboprobes and an anti-peptide antibody, we performed a series of in situ hybridization and immunolocalization studies to determine the distribution of PPARdelta in the central nervous system (CNS) of mice. We found that PPARdelta mRNA and protein is expressed throughout the brain, with particularly high levels in the entorhinal cortex, hypothalamus and hippocampus, and lower levels in the corpus callosum and caudate putamen. At the cellular level, PPARdelta mRNA and protein were found to be expressed in oligodendrocytes and neurons but not astrocytes. Such results suggest a role for PPARdelta in both myelination and neuronal functioning within the CNS.
Yield and turnover of illicit indoor cannabis (Cannabis spp.) plantations in Belgium.

PubMed

Vanhove, Wouter; Surmont, Tim; Van Damme, Patrick; De Ruyver, Brice

2012-07-10

In prosecution, Belgian judiciary currently uses outdated yield figures (28.1g per plant, sold at € 3/g at grower level) for fining illicit indoor cannabis plantations. Using state-of-the-art cultivation techniques, our growth experiments showed that yield is better expressed in g/m(2) cultivated surface area rather than in g per plant, and that yield varies significantly between different cannabis strains. It was found that the lower-bound of the one-sided 95% confidence interval of the yield of an indoor cannabis plantation can be set at 575 g/m(2). Prices and pricing mechanisms were investigated using interviews with respondents selected through snowball sampling. Results reveal that (i) the Belgian cannabis market chain is highly complex; (ii) unit prices are predominantly determined by transaction sizes; but also (iii) a set of product- and socially-related price-fixing mechanisms have an equally important role. At grower level, respondents reported prices for 1 g of dry cannabis buds to range € 3.00-4.25. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Novel Agricultural Conservation System with Sustained Yield and Decreased Water, Nutrient, Energy, and Carbon Footprints

NASA Astrophysics Data System (ADS)

Hansen, K.; Shukla, S.; Holt, N.; Hendricks, G.; Sishodia, R. P.

2017-12-01

Fresh fruits and vegetables are conventionally grown in raised bed plasticulture (RBP), a high intensity, high input, and high output production system. In 2016, the fresh market plasticulture industry covered 680,000 ha in the US, producing crops (e.g. tomato, peppers, melons, and strawberries) valued at ten billion dollars. To meet the increasing future demand for fresh fruits and vegetables and sustain the production potential of croplands, a transformation of the conventional food-water-energy nexus is essential. A novel agricultural conservation system, compact bed geometry, has been proposed to shift the paradigm in RBP, sustaining yield and decreasing inputs (e.g. water, nutrients, energy, and carbon). Compact bed geometries fit the shape of the wetting front created when water is applied through drip irrigation on the production soil, creating a taller (23-30 cm) and thinner bed (66-41 cm). Two seasons of tomato (single row) and pepper (double row) production, in the environmentally fragile watershed of the Florida Everglades, highlight the potential impact of compact bed geometry on environmental sustainability in agricultural production. No difference in plant growth or yield was detected, with a reduction of 5-50% in irrigation water, up to 20% less N application, 12% less P, 20% less K, and 5-15% less carbon dioxide emissions. The hydrologic benefits of compact bed geometry include 26% less runoff generation, decreased need for active drainage pumping, and increased residence time for irrigation water within the bed, overall decreasing instances of nutrient leaching. A water related co-benefit observed was a reduction in the occurrences of Phytophthora capsici in pepper, which has the potential to reduce yield by as much as 70%. Non-water co-benefits include up to a 250/ ha reduction in production cost, with the potential to save the industry 200 million dollars annually. This economic benefit has led to rapid industry adoption, with more than 20
Expression of a functional recombinant human basic fibroblast growth factor from transgenic rice seeds.

PubMed

An, Na; Ou, Jiquan; Jiang, Daiming; Zhang, Liping; Liu, Jingru; Fu, Kai; Dai, Ying; Yang, Daichang

2013-02-07

Basic fibroblast growth factor (FGF-2) is an important member of the FGF gene family. It is widely used in clinical applications for scald and wound healing in order to stimulate cell proliferation. Further it is applied for inhibiting stem cell differentiation in cultures. Due to a shortage of plasma and low expression levels of recombinant rbFGF in conventional gene expression systems, we explored the production of recombinant rbFGF in rice grains (Oryza sativa bFGF, OsrbFGF). An expression level of up to 185.66 mg/kg in brown rice was obtained. A simple purification protocol was established with final recovery of 4.49% and resulting in a yield of OsrbFGF reaching up to 8.33 mg/kg OsrbFGF. The functional assay of OsrbFGF indicated that the stimulating cell proliferation activity on NIH/3T3 was the same as with commercialized rbFGF. Wound healing in vivo of OsrbFGF is equivalent to commercialized rbFGF. Our results indicate that rice endosperm is capable of expressing small molecular mass proteins, such as bFGF. This again demonstrates that rice endosperm is a promising system to express various biopharmaceutical proteins.
In planta expression of HIV-1 p24 protein using an RNA plant virus-based expression vector.

PubMed

Zhang, G; Leung, C; Murdin, L; Rovinski, B; White, K A

2000-02-01

Plant viruses show significant potential as expression vectors for the production of foreign proteins (e.g., antigens) in plants. The HIV-1 p24 nucleocapsid protein is an important early marker of HIV infection and has been used as an antigen in the development of HIV vaccines. Toward developing a plant-based expression system for the production of p24, we have investigated the use of a (positive)-strand RNA plant virus, tomato bushy stunt virus (TBSV), as an expression vector. The HIV p24 open reading frame (ORF) was introduced into a cloned cDNA copy of the TBSV genome as an in-frame fusion with a 5'-terminal portion of the TBSV coat protein ORF. In vitro-generated RNA transcripts corresponding to the engineered virus vector were infectious when inoculated into plant protoplasts; Northern and Western blot analyses verified the accumulation of a predicted p24-encoding viral subgenomic mRNA and the production of p24 fusion product. Whole-plant infections with the viral vector led to the accumulation of p24 fusion protein in inoculated leaves, which cross-reacted with p24-specific antibodies, thus confirming the maintenance of key antigenic determinants. This study is the first to demonstrate that TBSV can be engineered to express a complete foreign protein of clinical importance. Strategies for optimizing protein yield from this viral vector are discussed.
Potato growth and yield using nutrient film technique (NFT)

NASA Technical Reports Server (NTRS)

Wheeler, R. M.; Mackowiak, C. L.; Sager, J. C.; Knott, W. M.; Hinkle, C. R.

1990-01-01

Potato plants, cvs Denali and Norland, were grown in polyvinyl chloride (PVC) trays using a continuous flowing nutrient film technique (NFT) to study tuber yield for NASA's Controlled Ecological Life Support Systems (CELSS) program. Nutrient solution pH was controlled automatically using 0.39M (2.5% (v/v) nitric acid (HNO3), while water and nutrients were replenished manually each day and twice each week, respectively. Plants were spaced either one or two per tray, allotting 0.2 or 0.4 m2 per plant. All plants were harvested after 112 days. Denali plants yielded 2850 and 2800 g tuber fresh weight from the one- and two-plant trays, respectively, while Norland plants yielded 1800 and 2400 g tuber fresh weight from the one- and two-plant trays. Many tubers of both cultivars showed injury to the periderm tissue, possibly caused by salt accumulation from the nutrient solution on the surface. Total system water usage throughout the study for all the plants equaled 709 liters (L), or approximately 2 L m-2 d-1. Total system acid usage throughout the study (for nutrient solution pH control) equaled 6.60 L, or 18.4 ml m-2 d-1 (7.2 mmol m-2 d-1). The results demonstrate that continuous flowing nutrient film technique can be used for tuber production with acceptable yields for the CELSS program.
Growth and Yield Estimation for Loblolly Pine in the West Gulf

Treesearch

Paul A. Murphy; Herbert S. Sternitzke

1979-01-01

An equation system is developed to estimate current yield, projected basal area, and projected volume for merchantable natural stands on a per-acre basis. These estimates indicate yields that can be expected from woods-run conditions.
What is adapted in face adaptation? The neural representations of expression in the human visual system.

PubMed

Fox, Christopher J; Barton, Jason J S

2007-01-05

The neural representation of facial expression within the human visual system is not well defined. Using an adaptation paradigm, we examined aftereffects on expression perception produced by various stimuli. Adapting to a face, which was used to create morphs between two expressions, substantially biased expression perception within the morphed faces away from the adapting expression. This adaptation was not based on low-level image properties, as a different image of the same person displaying that expression produced equally robust aftereffects. Smaller but significant aftereffects were generated by images of different individuals, irrespective of gender. Non-face visual, auditory, or verbal representations of emotion did not generate significant aftereffects. These results suggest that adaptation affects at least two neural representations of expression: one specific to the individual (not the image), and one that represents expression across different facial identities. The identity-independent aftereffect suggests the existence of a 'visual semantic' for facial expression in the human visual system.
Acid soil infertility effects on peanut yields and yield components

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

Blamey, F.P.C.

1983-01-01

The interpretation of soil amelioration experiments with peanuts is made difficult by the unpredictibility of the crop and by the many factors altered when ameliorating acid soils. The present study was conducted to investigate the effects of lime and gypsum applications on peanut kernel yield via the three first order yield components, pods per ha, kernels per pod, and kernel mass. On an acid medium sandy loam soil (typic Plinthustult), liming resulted in a highly significant kernel yield increase of 117% whereas gypsum applications were of no significant benefit. As indicated by path coefficient analysis, an increase in the numbermore » of pods per ha was markedly more important in increasing yield than an increase in either the number of kernels per pod or kernel mass. Furthermore, exch. Al was found to be particularly detrimental to pod number. It was postulated that poor peanut yields resulting from acid soil infertility were mainly due to the depressive effect of exch. Al on pod number. Exch. Ca appeared to play a secondary role by ameliorating the adverse effects of exch. Al.« less
Gene Expression Elucidates Functional Impact of Polygenic Risk for Schizophrenia

PubMed Central

Fromer, Menachem; Roussos, Panos; Sieberts, Solveig K; Johnson, Jessica S; Kavanagh, David H; Perumal, Thanneer M; Ruderfer, Douglas M; Oh, Edwin C; Topol, Aaron; Shah, Hardik R; Klei, Lambertus L; Kramer, Robin; Pinto, Dalila; Gümüş, Zeynep H; Cicek, A. Ercument; Dang, Kristen K; Browne, Andrew; Lu, Cong; Xie, Lu; Readhead, Ben; Stahl, Eli A; Parvizi, Mahsa; Hamamsy, Tymor; Fullard, John F; Wang, Ying-Chih; Mahajan, Milind C; Derry, Jonathan M J; Dudley, Joel; Hemby, Scott E; Logsdon, Benjamin A; Talbot, Konrad; Raj, Towfique; Bennett, David A; De Jager, Philip L; Zhu, Jun; Zhang, Bin; Sullivan, Patrick F; Chess, Andrew; Purcell, Shaun M; Shinobu, Leslie A; Mangravite, Lara M; Toyoshiba, Hiroyoshi; Gur, Raquel E; Hahn, Chang-Gyu; Lewis, David A; Haroutunian, Vahram; Peters, Mette A; Lipska, Barbara K; Buxbaum, Joseph D; Schadt, Eric E; Hirai, Keisuke; Roeder, Kathryn; Brennand, Kristen J; Katsanis, Nicholas; Domenici, Enrico; Devlin, Bernie; Sklar, Pamela

2016-01-01

Over 100 genetic loci harbor schizophrenia associated variants, yet how these variants confer liability is uncertain. The CommonMind Consortium sequenced RNA from dorsolateral prefrontal cortex of schizophrenia cases (N = 258) and control subjects (N = 279), creating a resource of gene expression and its genetic regulation. Using this resource, ~20% of schizophrenia loci have variants that could contribute to altered gene expression and liability. In five loci, only a single gene was involved: FURIN, TSNARE1, CNTN4, CLCN3, or SNAP91. Altering expression of FURIN, TSNARE1, or CNTN4 changes neurodevelopment in zebrafish; knockdown of FURIN in human neural progenitor cells yields abnormal migration. Of 693 genes showing significant case/control differential expression, their fold changes are ≤ 1.33, and an independent cohort yields similar results. Gene co-expression implicates a network relevant for schizophrenia. Our findings show schizophrenia is polygenic and highlight the utility of this resource for mechanistic interpretations of genetic liability for brain diseases. PMID:27668389
Gene expression elucidates functional impact of polygenic risk for schizophrenia.

PubMed

Fromer, Menachem; Roussos, Panos; Sieberts, Solveig K; Johnson, Jessica S; Kavanagh, David H; Perumal, Thanneer M; Ruderfer, Douglas M; Oh, Edwin C; Topol, Aaron; Shah, Hardik R; Klei, Lambertus L; Kramer, Robin; Pinto, Dalila; Gümüş, Zeynep H; Cicek, A Ercument; Dang, Kristen K; Browne, Andrew; Lu, Cong; Xie, Lu; Readhead, Ben; Stahl, Eli A; Xiao, Jianqiu; Parvizi, Mahsa; Hamamsy, Tymor; Fullard, John F; Wang, Ying-Chih; Mahajan, Milind C; Derry, Jonathan M J; Dudley, Joel T; Hemby, Scott E; Logsdon, Benjamin A; Talbot, Konrad; Raj, Towfique; Bennett, David A; De Jager, Philip L; Zhu, Jun; Zhang, Bin; Sullivan, Patrick F; Chess, Andrew; Purcell, Shaun M; Shinobu, Leslie A; Mangravite, Lara M; Toyoshiba, Hiroyoshi; Gur, Raquel E; Hahn, Chang-Gyu; Lewis, David A; Haroutunian, Vahram; Peters, Mette A; Lipska, Barbara K; Buxbaum, Joseph D; Schadt, Eric E; Hirai, Keisuke; Roeder, Kathryn; Brennand, Kristen J; Katsanis, Nicholas; Domenici, Enrico; Devlin, Bernie; Sklar, Pamela

2016-11-01

Over 100 genetic loci harbor schizophrenia-associated variants, yet how these variants confer liability is uncertain. The CommonMind Consortium sequenced RNA from dorsolateral prefrontal cortex of people with schizophrenia (N = 258) and control subjects (N = 279), creating a resource of gene expression and its genetic regulation. Using this resource, ∼20% of schizophrenia loci have variants that could contribute to altered gene expression and liability. In five loci, only a single gene was involved: FURIN, TSNARE1, CNTN4, CLCN3 or SNAP91. Altering expression of FURIN, TSNARE1 or CNTN4 changed neurodevelopment in zebrafish; knockdown of FURIN in human neural progenitor cells yielded abnormal migration. Of 693 genes showing significant case-versus-control differential expression, their fold changes were ≤ 1.33, and an independent cohort yielded similar results. Gene co-expression implicates a network relevant for schizophrenia. Our findings show that schizophrenia is polygenic and highlight the utility of this resource for mechanistic interpretations of genetic liability for brain diseases.
An orthogonal system for heterologous expression of actinobacterial lasso peptides in Streptomyces hosts.

PubMed

Mevaere, Jimmy; Goulard, Christophe; Schneider, Olha; Sekurova, Olga N; Ma, Haiyan; Zirah, Séverine; Afonso, Carlos; Rebuffat, Sylvie; Zotchev, Sergey B; Li, Yanyan

2018-05-29

Lasso peptides are ribosomally synthesized and post-translationally modified peptides produced by bacteria. They are characterized by an unusual lariat-knot structure. Targeted genome scanning revealed a wide diversity of lasso peptides encoded in actinobacterial genomes, but cloning and heterologous expression of these clusters turned out to be problematic. To circumvent this, we developed an orthogonal expression system for heterologous production of actinobacterial lasso peptides in Streptomyces hosts based on a newly-identified regulatory circuit from Actinoalloteichus fjordicus. Six lasso peptide gene clusters, mainly originating from marine Actinobacteria, were chosen for proof-of-concept studies. By varying the Streptomyces expression hosts and a small set of culture conditions, three new lasso peptides were successfully produced and characterized by tandem MS. The newly developed expression system thus sets the stage to uncover and bioengineer the chemo-diversity of actinobacterial lasso peptides. Moreover, our data provide some considerations for future bioprospecting efforts for such peptides.

The orphan nuclear receptor Nur77 regulates decidual prolactin expression in human endometrial stromal cells

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

Jiang, Yue; Hu, Yali; Zhao, Jing

2011-01-14

Research highlights: {yields} Decidually produced PRL plays a key role during pregnancy. {yields} Overexpression of Nur77 increased PRL mRNA expression and enhanced decidual PRL promoter activity. {yields} Knockdown of Nur77 decreased decidual PRL secretion induced by 8-Br-cAMP and MPA. {yields} Nur77 is a novel transcription factor that plays an active role in decidual prolactin expression. -- Abstract: Prolactin (PRL) is synthesized and released by several extrapituitary tissues, including decidualized stromal cells. Despite the important role of decidual PRL during pregnancy, little is understood about the factors involved in the proper regulation of decidual PRL expression. Here we present evidence thatmore » the transcription factor Nur77 plays an active role in decidual prolactin expression in human endometrial stromal cells (hESCs). Nur77 mRNA expression in hESCs was significantly increased after decidualization stimulated by 8-Br-cAMP and medroxyprogesterone acetate (MPA). Adenovirus-mediated overexpression of Nur77 in hESCs markedly increased PRL mRNA expression and enhanced decidual PRL promoter (dPRL/-332Luc) activity in a concentration-dependent manner. Furthermore, knockdown of Nur77 in hESCs significantly decreased decidual PRL promoter activation and substantially attenuated PRL mRNA expression and PRL secretion (P < 0.01) induced by 8-Br-cAMP and MPA. These results demonstrate that Nur77 is a novel transcription factor that contributes significantly to the regulation of prolactin gene expression in human endometrial stromal cells.« less
Modular and coordinated expression of immune system regulatory and signaling components in the developing and adult nervous system.

PubMed

Monzón-Sandoval, Jimena; Castillo-Morales, Atahualpa; Crampton, Sean; McKelvey, Laura; Nolan, Aoife; O'Keeffe, Gerard; Gutierrez, Humberto

2015-01-01

During development, the nervous system (NS) is assembled and sculpted through a concerted series of neurodevelopmental events orchestrated by a complex genetic programme. While neural-specific gene expression plays a critical part in this process, in recent years, a number of immune-related signaling and regulatory components have also been shown to play key physiological roles in the developing and adult NS. While the involvement of individual immune-related signaling components in neural functions may reflect their ubiquitous character, it may also reflect a much wider, as yet undescribed, genetic network of immune-related molecules acting as an intrinsic component of the neural-specific regulatory machinery that ultimately shapes the NS. In order to gain insights into the scale and wider functional organization of immune-related genetic networks in the NS, we examined the large scale pattern of expression of these genes in the brain. Our results show a highly significant correlated expression and transcriptional clustering among immune-related genes in the developing and adult brain, and this correlation was the highest in the brain when compared to muscle, liver, kidney and endothelial cells. We experimentally tested the regulatory clustering of immune system (IS) genes by using microarray expression profiling in cultures of dissociated neurons stimulated with the pro-inflammatory cytokine TNF-alpha, and found a highly significant enrichment of immune system-related genes among the resulting differentially expressed genes. Our findings strongly suggest a coherent recruitment of entire immune-related genetic regulatory modules by the neural-specific genetic programme that shapes the NS.
Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage Systems

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

Conover, David R.; Crawford, Aladsair J.; Fuller, Jason C.

The Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage Systems (PNNL-22010) was first issued in November 2012 as a first step toward providing a foundational basis for developing an initial standard for the uniform measurement and expression of energy storage system (ESS) performance. Based on experiences with the application and use of that document, and to include additional ESS applications and associated duty cycles, test procedures and performance metrics, a first revision of the November 2012 Protocol was issued in June 2014 (PNNL 22010 Rev. 1). As an update of the 2014 revision 1 to the Protocol,more » this document (the March 2016 revision 2 to the Protocol) is intended to supersede the June 2014 revision 1 to the Protocol and provide a more user-friendly yet more robust and comprehensive basis for measuring and expressing ESS performance.« less
Gene expression biomarkers provide sensitive indicators of in planta nitrogen status in maize.

PubMed

Yang, Xiaofeng S; Wu, Jingrui; Ziegler, Todd E; Yang, Xiao; Zayed, Adel; Rajani, M S; Zhou, Dafeng; Basra, Amarjit S; Schachtman, Daniel P; Peng, Mingsheng; Armstrong, Charles L; Caldo, Rico A; Morrell, James A; Lacy, Michelle; Staub, Jeffrey M

2011-12-01

Over the last several decades, increased agricultural production has been driven by improved agronomic practices and a dramatic increase in the use of nitrogen-containing fertilizers to maximize the yield potential of crops. To reduce input costs and to minimize the potential environmental impacts of nitrogen fertilizer that has been used to optimize yield, an increased understanding of the molecular responses to nitrogen under field conditions is critical for our ability to further improve agricultural sustainability. Using maize (Zea mays) as a model, we have characterized the transcriptional response of plants grown under limiting and sufficient nitrogen conditions and during the recovery of nitrogen-starved plants. We show that a large percentage (approximately 7%) of the maize transcriptome is nitrogen responsive, similar to previous observations in other plant species. Furthermore, we have used statistical approaches to identify a small set of genes whose expression profiles can quantitatively assess the response of plants to varying nitrogen conditions. Using a composite gene expression scoring system, this single set of biomarker genes can accurately assess nitrogen responses independently of genotype, developmental stage, tissue type, or environment, including in plants grown under controlled environments or in the field. Importantly, the biomarker composite expression response is much more rapid and quantitative than phenotypic observations. Consequently, we have successfully used these biomarkers to monitor nitrogen status in real-time assays of field-grown maize plants under typical production conditions. Our results suggest that biomarkers have the potential to be used as agronomic tools to monitor and optimize nitrogen fertilizer usage to help achieve maximal crop yields.
Nanobarcode gene expression monitoring system for potential miniaturized space applications

NASA Astrophysics Data System (ADS)

Ruan, Weiming; Eastman, P. Scott; Cooke, Patrick A.; Park, Jennifer S.; Chu, Julia S. F.; Gray, Joe W.; Li, Song; Chen, Fanqing Frank

Manned mission to space has been threatened by various cosmos risks including radiation, mirogravity, vacuum, confinement, etc., which may cause genetic variations of astronauts and eventually lead to damages of their health. Thus, the development of small biomedical devices, which can monitor astronaut gene expression changes, is useful for future long-term space missions. Using magnetic microbeads packed with nanocrystal quantum dots at controlled ratios, we were able to generate highly multiplexed nanobarcodes, which can encode a flexible panel of genes. Also, by using a reporter quantum dot, this nanobarcode platform can monitor and quantify gene expression level with improved speed and sensitivity. As a comparison, we studied TGF-β1 induced transcription changes in human bone marrow mesenchymal stem cells with both the nanobarcode microbead system and the Affymetrix GeneChip ® HTA system, which is currently considered as the industrial standard. Though using only 1/20 of the sample RNA, the nanobarcode system showed sensitivity equivalent to Affymetrix GeneChip ® system. The coefficient of variation, dynamic range, and accuracy of the nanobarcodes measurement is equivalent to that of the GeneChip ® HTA system. Therefore, this newly invented nanobarcode microbead platform is thought to be sensitive, flexible, cost-effective and accurate in a level equivalent to the conventional methods. As an extension of the use of this new platform, spacecrafts may carry this miniaturized system as a diagnostic tool for the astronauts.
Three-dimensional culture system can induce expression of casein in immortalized bovine mammary epithelial cells.

PubMed

Zhan, Kang; Lin, Miao; Liu, MingMei; Sui, YangNan; Babekir, Haitham Mohammed; Zhao, GuoQi

2017-05-01

Primary bovine mammary epithelial cells (BMECs) are not ideal models for long-term studies of lactation mechanisms because these cells in a monolayer culture system cannot be polarized to simulate the physiological functions in vitro. We investigate the effects of different culture models and karyotypes on casein expression in a three-dimensional (3D) culture system. The immortalized cells' karyotypes were analyzed at passages 10, 20, 30 and 40 to detect the effects of chromosome stability. Western blotting examined that whether or not the immortalized cells at passages 5, 10, 20, 30, 40 and 50 could induce expression of casein in a 3D culture system. The proper polarization of the acinar structures was monitored. BMECs were successfully immortalized. The cell karyotype at passage 30 remained at 60 chromosomes and the average value was 57.1 ± 0.40 after passage 40. The polarized protein's levels were up-regulated in 3D culture compared to 2D culture. Expression of αs1, β and κ-casein could be detectable in a passage range in 3D culture. Expression of αs2-casein was undetectable in all experimental groups. However, all casein expressions were barely detectable in traditional 2D culture system. Therefore, 3D culture system is an important tool for the long-term study of lactation mechanisms in vitro. © 2016 Japanese Society of Animal Science.
Estimates of genetics and phenotypics parameters for the yield and quality of soybean seeds.

PubMed

Zambiazzi, E V; Bruzi, A T; Guilherme, S R; Pereira, D R; Lima, J G; Zuffo, A M; Ribeiro, F O; Mendes, A E S; Godinho, S H M; Carvalho, M L M

2017-09-27

Estimating genotype x environment (GxE) parameters for quality and yield in soybean seed grown in different environments in Minas Gerais State was the goal of this study, as well as to evaluate interaction effects of GxE for soybean seeds yield and quality. Seeds were produced in three locations in Minas Gerais State (Lavras, Inconfidentes, and Patos de Minas) in 2013/14 and 2014/15 seasons. Field experiments were conducted in randomized blocks in a factorial 17 x 6 (GxE), and three replications. Seed yield and quality were evaluated for germination in substrates paper and sand, seedling emergence, speed emergency index, mechanical damage by sodium hypochlorite, electrical conductivity, speed aging, vigor and viability of seeds by tetrazolium test in laboratory using completely randomized design. Quadratic component genotypic, GXE variance component, genotype determination coefficient, genetic variation coefficient and environmental variation coefficient were estimated using the Genes software. Percentage analysis of genotypes contribution, environments and genotype x environment interaction were conducted by sites combination two by two and three sites combination, using the R software. Considering genotypes selection of broad adaptation, TMG 1179 RR, CD 2737 RR, and CD 237 RR associated better yield performance at high physical and physiological potential of seed. Environmental effect was more expressive for most of the characters related to soybean seed quality. GxE interaction effects were expressive though genotypes did not present coincidental behavior in different environments.
Loss of p21{sup Sdi1} expression in senescent cells after DNA damage accompanied with increase of miR-93 expression and reduced p53 interaction with p21{sup Sdi1} gene promoter

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

Choi, Ok Ran; Lim, In Kyoung, E-mail: iklim@ajou.ac.kr

2011-04-08

Highlights: {yields} Reduced p21 expression in senescent cells treated with DNA damaging agents. {yields} Increase of [{sup 3}H]thymidine and BrdU incorporations in DNA damaged-senescent cells. {yields} Upregulation of miR-93 expression in senescent cells in response to DSB. {yields} Failure of p53 binding to p21 promoter in senescent cells in response to DSB. {yields} Molecular mechanism of increased cancer development in aged than young individuals. -- Abstract: To answer what is a critical event for higher incidence of tumor development in old than young individuals, primary culture of human diploid fibroblasts were employed and DNA damage was induced by doxorubicin ormore » X-ray irradiation. Response to the damage was different between young and old cells; loss of p21{sup sdi1} expression in spite of p53{sup S15} activation in old cells along with [{sup 3}H]thymidine and BrdU incorporation, but not in young cells. The phenomenon was confirmed by other tissue fibroblasts obtained from different donor ages. Induction of miR-93 expression and reduced p53 binding to p21 gene promoter account for loss of p21{sup sdi1} expression in senescent cells after DNA damage, suggesting a mechanism of in vivo carcinogenesis in aged tissue without repair arrest.« less
Comparative Transcriptome Analysis of Latex Reveals Molecular Mechanisms Underlying Increased Rubber Yield in Hevea brasiliensis Self-Rooting Juvenile Clones

PubMed Central

Li, Hui-Liang; Guo, Dong; Zhu, Jia-Hong; Wang, Ying; Chen, Xiong-Ting; Peng, Shi-Qing

2016-01-01

Rubber tree (Hevea brasiliensis) self-rooting juvenile clones (JCs) are promising planting materials for rubber production. In a comparative trial between self-rooting JCs and donor clones (DCs), self-rooting JCs exhibited better performance in rubber yield. To study the molecular mechanism associated with higher rubber yield in self-rooting JCs, we sequenced and comparatively analyzed the latex of rubber tree self-rooting JCs and DCs at the transcriptome level. Total raw reads of 34,632,012 and 35,913,020 bp were obtained from the library of self-rooting JCs and DCs, respectively, by using Illumina HiSeq 2000 sequencing technology. De novo assemblies yielded 54689 unigenes from the library of self-rooting JCs and DCs. Among 54689 genes, 1716 genes were identified as differentially expressed between self-rooting JCs and DCs via comparative transcript profiling. Functional analysis showed that the genes related to the mass of categories were differentially enriched between the two clones. Several genes involved in carbohydrate metabolism, hormone metabolism and reactive oxygen species scavenging were up-regulated in self-rooting JCs, suggesting that the self-rooting JCs provide sufficient molecular basis for the increased rubber yielding, especially in the aspects of improved latex metabolisms and latex flow. Some genes encoding epigenetic modification enzymes were also differentially expressed between self-rooting JCs and DCs. Epigenetic modifications may lead to gene differential expression between self-rooting JCs and DCs. These data will provide new cues to understand the molecular mechanism underlying the improved rubber yield of H. brasiliensis self-rooting clones. PMID:27555864
Comparative Transcriptome Analysis of Latex Reveals Molecular Mechanisms Underlying Increased Rubber Yield in Hevea brasiliensis Self-Rooting Juvenile Clones.

PubMed

Li, Hui-Liang; Guo, Dong; Zhu, Jia-Hong; Wang, Ying; Chen, Xiong-Ting; Peng, Shi-Qing

2016-01-01

Rubber tree (Hevea brasiliensis) self-rooting juvenile clones (JCs) are promising planting materials for rubber production. In a comparative trial between self-rooting JCs and donor clones (DCs), self-rooting JCs exhibited better performance in rubber yield. To study the molecular mechanism associated with higher rubber yield in self-rooting JCs, we sequenced and comparatively analyzed the latex of rubber tree self-rooting JCs and DCs at the transcriptome level. Total raw reads of 34,632,012 and 35,913,020 bp were obtained from the library of self-rooting JCs and DCs, respectively, by using Illumina HiSeq 2000 sequencing technology. De novo assemblies yielded 54689 unigenes from the library of self-rooting JCs and DCs. Among 54689 genes, 1716 genes were identified as differentially expressed between self-rooting JCs and DCs via comparative transcript profiling. Functional analysis showed that the genes related to the mass of categories were differentially enriched between the two clones. Several genes involved in carbohydrate metabolism, hormone metabolism and reactive oxygen species scavenging were up-regulated in self-rooting JCs, suggesting that the self-rooting JCs provide sufficient molecular basis for the increased rubber yielding, especially in the aspects of improved latex metabolisms and latex flow. Some genes encoding epigenetic modification enzymes were also differentially expressed between self-rooting JCs and DCs. Epigenetic modifications may lead to gene differential expression between self-rooting JCs and DCs. These data will provide new cues to understand the molecular mechanism underlying the improved rubber yield of H. brasiliensis self-rooting clones.
A fluorimetric study of the thorium-morin system

USGS Publications Warehouse

Milkey, Robert G.; Fletcher, Mary H.

1956-01-01

Thorium reacts with morin to yield a yellow complex that fluoresces when irradiated with ultraviolet light. The effect on the fluorescence of such variable as concentration of acid, alcohol, thorium, morin, and complex; time, temperature, and wavelength of exciting light are studied to determine experimental conditions yielding maximum fluorescence. The effects of Zr4+, Al3+, Fe3+, Ca2+, and La3+ are discussed. The fundamental relationships between light absorption and fluorescence are expressed in a general equation which applied to a three-component system when the fluorescence is measured in a transmission-type fluorimeter. This general equation is used to obtain an expression for the fluorescence of the thorium-morin system. Equations, derived from experimental data, related both the fraction of thorium reacted to form complex and the fraction of unquenched fluorescence to the concentration of uncombined morin. These functions, when combined with the general equation, give an expression which relates the total net fluorescence to the amount of uncombined morin in the solution. This last equation can be used to determine the one region for the concentration of uncombined morin that gives maximum sensitivity for the system. Calculated standard curves are in excellent agreement with experimental curves.
Evaluation of exercise-respiratory system modifications and integration schemes for physiological systems

NASA Technical Reports Server (NTRS)

Gallagher, R. R.

1974-01-01

Exercise subroutine modifications are implemented in an exercise-respiratory system model yielding improvement of system response to exercise forcings. A more physiologically desirable respiratory ventilation rate in addition to an improved regulation of arterial gas tensions and cerebral blood flow is observed. A respiratory frequency expression is proposed which would be appropriate as an interfacing element of the respiratory-pulsatile cardiovascular system. Presentation of a circulatory-respiratory system integration scheme along with its computer program listing is given. The integrated system responds to exercise stimulation for both nonstressed and stressed physiological states. Other integration possibilities are discussed with respect to the respiratory, pulsatile cardiovascular, thermoregulatory, and the long-term circulatory systems.
aGEM: an integrative system for analyzing spatial-temporal gene-expression information

PubMed Central

Jiménez-Lozano, Natalia; Segura, Joan; Macías, José Ramón; Vega, Juanjo; Carazo, José María

2009-01-01

Motivation: The work presented here describes the ‘anatomical Gene-Expression Mapping (aGEM)’ Platform, a development conceived to integrate phenotypic information with the spatial and temporal distributions of genes expressed in the mouse. The aGEM Platform has been built by extending the Distributed Annotation System (DAS) protocol, which was originally designed to share genome annotations over the WWW. DAS is a client-server system in which a single client integrates information from multiple distributed servers. Results: The aGEM Platform provides information to answer three main questions. (i) Which genes are expressed in a given mouse anatomical component? (ii) In which mouse anatomical structures are a given gene or set of genes expressed? And (iii) is there any correlation among these findings? Currently, this Platform includes several well-known mouse resources (EMAGE, GXD and GENSAT), hosting gene-expression data mostly obtained from in situ techniques together with a broad set of image-derived annotations. Availability: The Platform is optimized for Firefox 3.0 and it is accessed through a friendly and intuitive display: http://agem.cnb.csic.es Contact: natalia@cnb.csic.es Supplementary information: Supplementary data are available at http://bioweb.cnb.csic.es/VisualOmics/aGEM/home.html and http://bioweb.cnb.csic.es/VisualOmics/index_VO.html and Bioinformatics online. PMID:19592395
Optimized Assembly of a Multifunctional RNA-Protein Nanostructure in a Cell-Free Gene Expression System.

PubMed

Schwarz-Schilling, Matthaeus; Dupin, Aurore; Chizzolini, Fabio; Krishnan, Swati; Mansy, Sheref S; Simmel, Friedrich C

2018-04-11

Molecular complexes composed of RNA molecules and proteins are promising multifunctional nanostructures for a wide variety of applications in biological cells or in artificial cellular systems. In this study, we systematically address some of the challenges associated with the expression and assembly of such hybrid structures using cell-free gene expression systems. As a model structure, we investigated a pRNA-derived RNA scaffold functionalized with four distinct aptamers, three of which bind to proteins, streptavidin and two fluorescent proteins, while one binds the small molecule dye malachite green (MG). Using MG fluorescence and Förster resonance energy transfer (FRET) between the RNA-scaffolded proteins, we assess critical assembly parameters such as chemical stability, binding efficiency, and also resource sharing effects within the reaction compartment. We then optimize simultaneous expression and coassembly of the RNA-protein nanostructure within a single-compartment cell-free gene expression system. We demonstrate expression and assembly of the multicomponent nanostructures inside of emulsion droplets and their aptamer-mediated localization onto streptavidin-coated substrates, plus the successful assembly of the hybrid structures inside of bacterial cells.
Meteorological fluctuations define long-term crop yield patterns in conventional and organic production systems

USDA-ARS?s Scientific Manuscript database

Periodic variability in meteorological patterns presents significant challenges to crop production consistency and yield stability. Meteorological influences on corn and soybean grain yields were analyzed over an 18-year period at a long-term experiment in Beltsville, Maryland, U.S.A., comparing c...
Multilevel Regulation of Bacterial Gene Expression with the Combined STAR and Antisense RNA System.

PubMed

Lee, Young Je; Kim, Soo-Jung; Moon, Tae Seok

2018-03-16

Synthetic small RNA regulators have emerged as a versatile tool to predictably control bacterial gene expression. Owing to their simple design principles, small size, and highly orthogonal behavior, these engineered genetic parts have been incorporated into genetic circuits. However, efforts to achieve more sophisticated cellular functions using RNA regulators have been hindered by our limited ability to integrate different RNA regulators into complex circuits. Here, we present a combined RNA regulatory system in Escherichia coli that uses small transcription activating RNA (STAR) and antisense RNA (asRNA) to activate or deactivate target gene expression in a programmable manner. Specifically, we demonstrated that the activated target output by the STAR system can be deactivated by expressing two different types of asRNAs: one binds to and sequesters the STAR regulator, affecting the transcription process, while the other binds to the target mRNA, affecting the translation process. We improved deactivation efficiencies (up to 96%) by optimizing each type of asRNA and then integrating the two optimized asRNAs into a single circuit. Furthermore, we demonstrated that the combined STAR and asRNA system can control gene expression in a reversible way and can regulate expression of a gene in the genome. Lastly, we constructed and simultaneously tested two A AND NOT B logic gates in the same cell to show sophisticated multigene regulation by the combined system. Our approach establishes a methodology for integrating multiple RNA regulators to rationally control multiple genes.
Expression of POEM, a positive regulator of osteoblast differentiation, is suppressed by TNF-{alpha}

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

Tsukasaki, Masayuki; Yamada, Atsushi, E-mail: yamadaa@dent.showa-u.ac.jp; Suzuki, Dai

2011-07-15

Highlights: {yields} TNF-{alpha} inhibits POEM gene expression. {yields} Inhibition of POEM gene expression is caused by NF-{kappa}B activation by TNF-{alpha}. {yields} Over-expression of POEM recovers inhibition of osteoblast differentiation by TNF-{alpha}. -- Abstract: POEM, also known as nephronectin, is an extracellular matrix protein considered to be a positive regulator of osteoblast differentiation. In the present study, we found that tumor necrosis factor-{alpha} (TNF-{alpha}), a key regulator of bone matrix properties and composition that also inhibits terminal osteoblast differentiation, strongly inhibited POEM expression in the mouse osteoblastic cell line MC3T3-E1. TNF-{alpha}-induced down-regulation of POEM gene expression occurred in both time- andmore » dose-dependent manners through the nuclear factor kappa B (NF-{kappa}B) pathway. In addition, expressions of marker genes in differentiated osteoblasts were down-regulated by TNF-{alpha} in a manner consistent with our findings for POEM, while over-expression of POEM recovered TNF-{alpha}-induced inhibition of osteoblast differentiation. These results suggest that TNF-{alpha} inhibits POEM expression through the NF-{kappa}B signaling pathway and down-regulation of POEM influences the inhibition of osteoblast differentiation by TNF-{alpha}.« less
Optimization of insect cell based protein production processes - online monitoring, expression systems, scale up.

PubMed

Druzinec, Damir; Salzig, Denise; Brix, Alexander; Kraume, Matthias; Vilcinskas, Andreas; Kollewe, Christian; Czermak, Peter

2013-01-01

Due to the increasing use of insect cell based expression systems in research and industrial recombinant protein production, the development of efficient and reproducible production processes remains a challenging task. In this context, the application of online monitoring techniques is intended to ensure high and reproducible product qualities already during the early phases of process development. In the following chapter, the most common transient and stable insect cell based expression systems are briefly introduced. Novel applications of insect cell based expression systems for the production of insect derived antimicrobial peptides/proteins (AMPs) are discussed using the example of G. mellonella derived gloverin. Suitable in situ sensor techniques for insect cell culture monitoring in disposable and common bioreactor systems are outlined with respect to optical and capacitive sensor concepts. Since scale up of production processes is one of the most critical steps in process development, a conclusive overview is given about scale up aspects for industrial insect cell culture processes.
Yield Advances in Peanut

USDA-ARS?s Scientific Manuscript database

Average yields of peanut in the U.S. set an all time record of 4,695 kg ha-1 in 2012. This far exceeded the previous record yield of 3,837 kg ha-1 in 2008. Favorable weather conditions undoubtedly contributed to the record yields in 2012; however, these record yields would not have been achievable...
Gene expression analysis predicts insect venom anaphylaxis in indolent systemic mastocytosis.

PubMed

Niedoszytko, M; Bruinenberg, M; van Doormaal, J J; de Monchy, J G R; Nedoszytko, B; Koppelman, G H; Nawijn, M C; Wijmenga, C; Jassem, E; Elberink, J N G Oude

2011-05-01

Anaphylaxis to insect venom (Hymenoptera) is most severe in patients with mastocytosis and may even lead to death. However, not all patients with mastocytosis suffer from anaphylaxis. The aim of the study was to analyze differences in gene expression between patients with indolent systemic mastocytosis (ISM) and a history of insect venom anaphylaxis (IVA) compared to those patients without a history of anaphylaxis, and to determine the predictive use of gene expression profiling. Whole-genome gene expression analysis was performed in peripheral blood cells. Twenty-two adults with ISM were included: 12 with a history of IVA and 10 without a history of anaphylaxis of any kind. Significant differences in single gene expression corrected for multiple testing were found for 104 transcripts (P < 0.05). Gene ontology analysis revealed that the differentially expressed genes were involved in pathways responsible for the development of cancer and focal and cell adhesion suggesting that the expression of genes related to the differentiation state of cells is higher in patients with a history of anaphylaxis. Based on the gene expression profiles, a naïve Bayes prediction model was built identifying patients with IVA. In ISM, gene expression profiles are different between patients with a history of IVA and those without. These findings might reflect a more pronounced mast cells dysfunction in patients without a history of anaphylaxis. Gene expression profiling might be a useful tool to predict the risk of anaphylaxis on insect venom in patients with ISM. Prospective studies are needed to substantiate any conclusions. © 2010 John Wiley & Sons A/S.

The metabolic costs of improving ethanol yield by reducing glycerol formation capacity under anaerobic conditions in Saccharomyces cerevisiae.

PubMed

Pagliardini, Julien; Hubmann, Georg; Alfenore, Sandrine; Nevoigt, Elke; Bideaux, Carine; Guillouet, Stephane E

2013-03-28

Finely regulating the carbon flux through the glycerol pathway by regulating the expression of the rate controlling enzyme, glycerol-3-phosphate dehydrogenase (GPDH), has been a promising approach to redirect carbon from glycerol to ethanol and thereby increasing the ethanol yield in ethanol production. Here, strains engineered in the promoter of GPD1 and deleted in GPD2 were used to investigate the possibility of reducing glycerol production of Saccharomyces cerevisiae without jeopardising its ability to cope with process stress during ethanol production. For this purpose, the mutant strains TEFmut7 and TEFmut2 with different GPD1 residual expression were studied in Very High Ethanol Performance (VHEP) fed-batch process under anaerobic conditions. Both strains showed a drastic reduction of the glycerol yield by 44 and 61% while the ethanol yield improved by 2 and 7% respectively. TEFmut2 strain showing the highest ethanol yield was accompanied by a 28% reduction of the biomass yield. The modulation of the glycerol formation led to profound redox and energetic changes resulting in a reduction of the ATP yield (YATP) and a modulation of the production of organic acids (acetate, pyruvate and succinate). Those metabolic rearrangements resulted in a loss of ethanol and stress tolerance of the mutants, contrarily to what was previously observed under aerobiosis. This work demonstrates the potential of fine-tuned pathway engineering, particularly when a compromise has to be found between high product yield on one hand and acceptable growth, productivity and stress resistance on the other hand. Previous study showed that, contrarily to anaerobiosis, the resulting gain in ethanol yield was accompanied with no loss of ethanol tolerance under aerobiosis. Moreover those mutants were still able to produce up to 90 gl-1 ethanol in an anaerobic SSF process. Fine tuning metabolic strategy may then open encouraging possibilities for further developing robust strains with improved
Epigenetic regulation of the transcription factor Foxa2 directs differential elafin expression in melanocytes and melanoma cells

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

Yu, Kyung Sook; Jo, Ji Yoon; Kim, Su Jin

2011-04-29

Highlights: {yields} Elafin expression is epigenetically silenced in human melanoma cells. {yields} Foxa2 expression in melanoma cells is silenced by promoter hypermethylation. {yields} Foxa2 directs activation of the elafin promoter in vivo. {yields} Foxa2 expression induces apoptosis of melanoma cells via elafin re-expression. -- Abstract: Elafin, a serine protease inhibitor, induces the intrinsic apoptotic pathway in human melanoma cells, where its expression is transcriptionally silenced. However, it remains unknown how the elafin gene is repressed in melanoma cells. We here demonstrate that elafin expression is modulated via epigenetically regulated expression of the transcription factor Foxa2. Treatment of melanoma cells withmore » a DNA methyltransferase inhibitor induced elafin expression, which was specifically responsible for reduced proliferation and increased apoptosis. Suppression of Foxa2 transcription, mediated by DNA hypermethylation in its promoter region, was released in melanoma cells upon treatment with the demethylating agent. Luciferase reporter assays indicated that the Foxa2 binding site in the elafin promoter was critical for the activation of the promoter. Chromatin immunoprecipitation assays further showed that Foxa2 bound to the elafin promoter in vivo. Analyses of melanoma cells with varied levels of Foxa2 revealed a correlated expression between Foxa2 and elafin and the ability of Foxa2 to induce apoptosis. Our results collectively suggest that, in melanoma cells, Foxa2 expression is silenced and therefore elafin is maintained unexpressed to facilitate cell proliferation in the disease melanoma.« less
Impact of liquid fertilizers on plant growth, yield, fruit quality and fertigation management in an organic processing blackberry production system

USDA-ARS?s Scientific Manuscript database

The impact of organic fertilizer source on the growth, fruit quality, and yield of blackberry cultivars (‘Marion’ and ‘Black Diamond’) grown in machine-harvested, organic production systems for the processed market was evaluated from 2011-13. The planting was established in spring 2010 using approve...
Assimilating remote sensing observations of leaf area index and soil moisture for wheat yield estimates: An observing system simulation experiment

USDA-ARS?s Scientific Manuscript database

We develop a robust understanding of the effects of assimilating remote sensing observations of leaf area index and soil moisture (in the top 5 cm) on DSSAT-CSM CropSim-Ceres wheat yield estimates. Synthetic observing system simulation experiments compare the abilities of the Ensemble Kalman Filter...
Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage Systems

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

Conover, David R.; Crawford, Aladsair J.; Viswanathan, Vilayanur V.

2014-06-01

The Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage Systems (PNNL-22010) was first issued in November 2012 as a first step toward providing a foundational basis for developing an initial standard for the uniform measurement and expression of energy storage system (ESS) performance. Its subsequent use in the field and review by the protocol working group and most importantly the users’ subgroup and the thermal subgroup has led to the fundamental modifications reflected in this update of the 2012 Protocol. As an update of the 2012 Protocol, this document (the June 2014 Protocol) is intended to supersedemore » its predecessor and be used as the basis for measuring and expressing ESS performance. The foreword provides general and specific details about what additions, revisions, and enhancements have been made to the 2012 Protocol and the rationale for them in arriving at the June 2014 Protocol.« less
Expression of classical components of the renin-angiotensin system in the human eye.

PubMed

White, Andrew J R; Cheruvu, Sarat C; Sarris, Maria; Liyanage, Surabhi S; Lumbers, Eugenie; Chui, Jeanie; Wakefield, Denis; McCluskey, Peter J

2015-03-01

The purpose of this study was to determine the relative expression of clinically-relevant components of the renin-angiotensin system (RAS) in the adult human eye. We obtained 14 post-mortem enucleated human eyes from patients whom had no history of inflammatory ocular disease nor pre-mortem ocular infection. We determined the gene expression for prorenin, renin, prorenin receptor, angiotensin-converting enzyme, angiotensinogen and angiotensin II Type 1 receptor, on tissue sections and in cultured human primary retinal pigment epithelial and iris pigment epithelial (RPE/IPE) cell lines, using both qualitative and quantitative reverse transcription polymerase chain reaction (RT-PCR). Protein expression was studied using indirect immunofluorescence (IF). Almost all components of the classical RAS were found at high levels, at both the transcript and protein level, in the eyes' uvea and retina; and at lower levels in the cornea, conjunctiva and sclera. There was a much lower level of expression in the reference cultured RPE/IPE cells lines. This study describes the distribution of RAS in the normal adult human eye and demonstrates the existence of an independent ocular RAS, with uveal and retinal tissues showing the highest expression of RAS components. These preliminary findings provide scope for examination of additional components of this system in the human eye, as well as possible differential expression under pathological conditions. © The Author(s) 2014.
[DNA extraction from bones and teeth using AutoMate Express forensic DNA extraction system].

PubMed

Gao, Lin-Lin; Xu, Nian-Lai; Xie, Wei; Ding, Shao-Cheng; Wang, Dong-Jing; Ma, Li-Qin; Li, You-Ying

2013-04-01

To explore a new method in order to extract DNA from bones and teeth automatically. Samples of 33 bones and 15 teeth were acquired by freeze-mill method and manual method, respectively. DNA materials were extracted and quantified from the triturated samples by AutoMate Express forensic DNA extraction system. DNA extraction from bones and teeth were completed in 3 hours using the AutoMate Express forensic DNA extraction system. There was no statistical difference between the two methods in the DNA concentration of bones. Both bones and teeth got the good STR typing by freeze-mill method, and the DNA concentration of teeth was higher than those by manual method. AutoMate Express forensic DNA extraction system is a new method to extract DNA from bones and teeth, which can be applied in forensic practice.
Projecting crop yield in northern high latitude area.

PubMed

Matsumura, Kanichiro

2014-01-01

validation periods is used. To show the reproducing projection between observed and calculated values, the root mean squared error for skill score (RMSE SS) with the persistence model serving as the reference model is used. The persistence model is used as a benchmark. The results show that SADs near USA border show better RMSE SS values and mode 3's time coefficients can be a useful predictor especially for inland province such as Manitoba. Among 27 Canadian Prairie's SADs with perfect yield data, 67% of Alberta's SADs, 86% of Manitoba's SADs, and 77% of Saskatchewan's SADs can get positive skill scores. In each SAD, future yield projection is calculated applying predictors in 2013 for the obtained eight sets of models and eight sets of forecasted values in 2013 are averaged and a near future projection result is obtained. Series of outputs including calculated forecasted yield value in each SAD is provided by smart phone application. A system for providing climatic condition for a point with a permission of Climatic Research Unit - University of East Anglia and for obtaining patent is proposed. There are several patented systems similar to the system proposed in this paper. However, these patents are different in essence. The system proposed in this paper consists of two parts. First part is to estimate equations using time series data. The second part is to acquire and apply latest climatic conditions for obtained equations and calculate future projection. If the procedure is refined and devices are originally developed, series of idea can be patented. For future work, crop index, Hokkaido is also introduced.
New method to enhance the extraction yield of rutin from Sophora japonica using a novel ultrasonic extraction system by determining optimum ultrasonic frequency.

PubMed

Liao, Jianqing; Qu, Baida; Liu, Da; Zheng, Naiqin

2015-11-01

A new method has been proposed for enhancing extraction yield of rutin from Sophora japonica, in which a novel ultrasonic extraction system has been developed to perform the determination of optimum ultrasonic frequency by a two-step procedure. This study has systematically investigated the influence of a continuous frequency range of 20-92 kHz on rutin yields. The effects of different operating conditions on rutin yields have also been studied in detail such as solvent concentration, solvent to solid ratio, ultrasound power, temperature and particle size. A higher extraction yield was obtained at the ultrasonic frequency of 60-62 kHz which was little affected under other extraction conditions. Comparative studies between existing methods and the present method were done to verify the effectiveness of this method. Results indicated that the new extraction method gave a higher extraction yield compared with existing ultrasound-assisted extraction (UAE) and soxhlet extraction (SE). Thus, the potential use of this method may be promising for extraction of natural materials on an industrial scale in the future. Copyright © 2015 Elsevier B.V. All rights reserved.
Maintaining yields and reducing nitrogen loss in rice-wheat rotation system in Taihu Lake region with proper fertilizer management

NASA Astrophysics Data System (ADS)

Xue, Lihong; Yu, Yingliang; Yang, Linzhang

2014-11-01

In the Tailake region of China, heavy nitrogen (N) loss of rice-wheat rotation systems, due to high fertilizer-N input with low N use efficiency (NUE), was widely reported. To alleviate the detrimental impacts caused by N loss, it is necessary to improve the fertilizer management practices. Therefore, a 3 yr field experiments with different N managements including organic combined chemical N treatment (OCN, 390 kg N ha-1 yr-1, 20% organic fertilizer), control-released urea treatment (CRU, 390 kg N ha-1 yr-1, 70% resin-coated urea), reduced chemical N treatment (RCN, 390 kg N ha-1 yr-1, all common chemical fertilizer), and site-specific N management (SSNM, 333 kg N ha-1 yr-1, all common chemical fertilizer) were conducted in the Taihu Lake region with the ‘farmer’s N’ treatment (FN, 510 kg N ha-1 yr-1, all common chemical fertilizer) as a control. Grain yield, plant N uptake (PNU), NUE, and N losses via runoff, leaching, and ammonia volatilization were assessed. In the rice season, the FN treatment had the highest N loss and lowest NUE, which can be attributed to an excessive rate of N application. Treatments of OCN and RCN with a 22% reduced N rate from FN had no significant effect on PNU nor the yield of rice in the 3 yr; however, the NUE was improved and N loss was reduced 20-32%. OCN treatment achieved the highest yield, while SSNM has the lowest N loss and highest NUE due to the lowest N rate. In wheat season, N loss decreased about 28-48% with the continuous reduction of N input, but the yield also declined, with the exception of OCN treatment. N loss through runoff, leaching and ammonia volatilization was positively correlated with the N input rate. When compared with the pure chemical fertilizer treatment of RCN under the same N input, OCN treatment has better NUE, better yield, and lower N loss. 70% of the urea replaced with resin-coated urea had no significant effect on yield and NUE improvement, but decreased the ammonia volatilization loss. Soil
Scaling and Thermal Evolution of Internally Heated Planets: Yield Stress and Thermal History.

NASA Astrophysics Data System (ADS)

Weller, M. B.; Lenardic, A.; Moore, W. B.

2014-12-01

Using coupled 3D mantle convection and planetary tectonics models of bi-stable systems, we show how system behaviors for mobile-lid and stagnant-lid states scale as functions of internal heating rates (Q) and basal Ra (Rab). With parameter ranges for temperature- and depth-dependant viscosities: 1e4 - 3e4, Rab: 1e5- 3e5, Q: 0 - 100, and yield stress: 1e4 - 2e5, it can be shown the internal temperatures, velocities, heat fluxes, and system behaviors for mobile-lid and stagnant-lid states diverge, for equivalent parameter values, as a function of increasing Q. For the mobile-lid regime, yielding behavior in the upper boundary layer strongly influences the dynamics of the system. Internal temperatures, and consequently temperature-dependant viscosities, vary strongly as a function of yield stress for a given Q. The temperature distribution across the upper and lower mantles are sub-adiabatic for low to moderate yield stress, and adiabatic to super-adiabatic for high yield stresses. Across the parameter range considered, and for fixed yield stress, the Nu across the basal boundary (Nub) is positive and only weakly dependant on Q (varies by ~ 9%). Nub varies strongly as a function of yield stress (maximum variation of ~84%). Both mobile-lid velocities and lid-thicknesses are yield stress dependant for a given Q and Ra. In contrast to mobile-lids, the stagnant-lid regime is governed by the relative inefficiency of heat transport through the surface boundary layer. Internal temperatures are yield stress independent, and are on average 30% greater. Nub has a strong dependence on heating rates and surface boundary layer thicknesses. Within the parameter space considered, the maximum stagnant-lid Nub corresponds to the minimum mobile-lid Nub (for high yield stress), and decreases with increasing Q. For high Q, super-heated stagnant-lids may develop, with Nub< 0, and changes in trends for system behaviors. Planets with high levels of internal heating and/or high yield
VITELLOGENIN EXPRESSION IN SHEEPSHEAD MINNOWS FROM THE PENSACOLA BAY SYSTEM

EPA Science Inventory

Hemmer, M.J., B.L. Hemmer, S.D. Friedman and P.S. Harris. In press. Vitellogenin Expression in Populations of Sheepshead Minnows from the Pensacola Bay System (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portland, OR. 1 p. (ERL,GB R1015). <...
Upregulation of gene expression in reward-modulatory striatal opioid systems by sleep loss.

PubMed

Baldo, Brian A; Hanlon, Erin C; Obermeyer, William; Bremer, Quentin; Paletz, Elliott; Benca, Ruth M

2013-12-01

Epidemiological studies have shown a link between sleep loss and the obesity 'epidemic,' and several observations indicate that sleep curtailment engenders positive energy balance via increased palatable-food 'snacking.' These effects suggest alterations in reward-modulatory brain systems. We explored the effects of 10 days of sleep deprivation in rats on the expression of striatal opioid peptide (OP) genes that subserve food motivation and hedonic reward, and compared effects with those seen in hypothalamic energy balance-regulatory systems. Sleep-deprived (Sleep-Dep) rats were compared with yoked forced-locomotion apparatus controls (App-Controls), food-restricted rats (Food-Restrict), and unmanipulated controls (Home-Cage). Detection of mRNA levels with in situ hybridization revealed a subregion-specific upregulation of striatal preproenkephalin and prodynorhin gene expression in the Sleep-Dep group relative to all other groups. Neuropeptide Y (NPY) gene expression in the hippocampal dentate gyrus and throughout neocortex was also robustly upregulated selectively in the Sleep-Dep group. In contrast, parallel gene expression changes were observed in the Sleep-Dep and Food-Restrict groups in hypothalamic energy-sensing systems (arcuate nucleus NPY was upregulated, and cocaine- and amphetamine-regulated transcript was downregulated), in alignment with leptin suppression in both groups. Together, these results reveal a novel set of sleep deprivation-induced transcriptional changes in reward-modulatory peptide systems, which are dissociable from the energy-balance perturbations of sleep loss or the potentially stressful effects of the forced-locomotion procedure. The recruitment of telencephalic food-reward systems may provide a feeding drive highly resistant to feedback control, which could engender obesity through the enhancement of palatable feeding.
Transjugular liver biopsy with use of the shark jaw needle: diagnostic yield, complications, and cost-effectiveness.

PubMed

Psooy, B J; Clark, T W; Beecroft, J R; Malatjalian, D

2001-01-01

Obtaining transjugular liver biopsy specimens with use of single-use needle systems is expensive, whereas biopsy specimens obtained with use of reusable needle systems are frequently associated with inadequate core specimens. The authors report their experience with the reusable Cook Shark Jaw biopsy needle, including diagnostic yield, complications, and cost-effectiveness. A retrospective audit was performed of a cohort of 134 patients who underwent 136 transjugular liver biopsies with use of a reusable 16-gauge Shark Jaw needle during a 30-month period. Specimen adequacy and complication rates were assessed and direct costs of expendable components calculated. Cost-effectiveness was expressed as cost-per-successful biopsy. Biopsies were technically successful in 126 of 136 (93%) patients, with diagnostic histologic core specimens obtained in 124 of 126 (98%) patients, for an overall success rate of 91%. Complications included capsular penetration in six (4.4%) patients, cardiac arrhythmia in two (1.5%) patients, and puncture site hematoma or bleeding in 10 (7.4%) patients. Three tract embolizations were performed for capsular penetration. No instances of subcapsular hematoma, hemoperitoneum, or sepsis occurred, and no deaths were attributed to the procedure. The cost of expendable components totaled $103 per biopsy, corresponding to a cost-effectiveness of $113/successful biopsy. Transjugular liver biopsy specimens obtained with use of the Shark Jaw needle have a diagnostic yield comparable to those obtained with use of single-use biopsy systems, at a substantially lower cost with no increase in serious complications.
Water consumption, grain yield, and water productivity in response to field water management in double rice systems in China.

PubMed

Wu, Xiao Hong; Wang, Wei; Yin, Chun Mei; Hou, Hai Jun; Xie, Ke Jun; Xie, Xiao Li

2017-01-01

Rice cultivation has been challenged by increasing food demand and water scarcity. We examined the responses of water use, grain yield, and water productivity to various modes of field water managements in Chinese double rice systems. Four treatments were studied in a long-term field experiment (1998-2015): continuous flooding (CF), flooding-midseason drying-flooding (F-D-F), flooding-midseason drying-intermittent irrigation without obvious standing water (F-D-S), and flooding-rain-fed (F-RF). The average precipitation was 483 mm in early-rice season and 397 mm in late-rice season. The irrigated water for CF, F-D-F, F-D-S, and F-RF, respectively, was 263, 340, 279, and 170 mm in early-rice season, and 484, 528, 422, and 206 mm in late-rice season. Grain yield for CF, F-D-F, F-D-S, and F-RF, respectively, was 4,722, 4,597, 4,479, and 4,232 kgha-1 in early-rice season, and 5,420, 5,402, 5,366, and 4,498 kgha-1 in late-rice season. Compared with CF, F-D-F consumed more irrigated water, which still decreased grain yield, leading to a decrease in water productivity by 25% in early-rice season and by 8% in late-rice season. Compared with F-D-F, F-D-S saved much irrigated water with a small yield reduction, leading to an increase in water productivity by 22% in early-rice season and by 26% in late-rice season. The results indicate that CF is best for early-rice and FDS is best for late-rice in terms of grain yield and water productivity.
Heterologous viral expression systems in fosmid vectors increase the functional analysis potential of metagenomic libraries.

PubMed

Terrón-González, L; Medina, C; Limón-Mortés, M C; Santero, E

2013-01-01

The extraordinary potential of metagenomic functional analyses to identify activities of interest present in uncultured microorganisms has been limited by reduced gene expression in surrogate hosts. We have developed vectors and specialized E. coli strains as improved metagenomic DNA heterologous expression systems, taking advantage of viral components that prevent transcription termination at metagenomic terminators. One of the systems uses the phage T7 RNA-polymerase to drive metagenomic gene expression, while the other approach uses the lambda phage transcription anti-termination protein N to limit transcription termination. A metagenomic library was constructed and functionally screened to identify genes conferring carbenicillin resistance to E. coli. The use of these enhanced expression systems resulted in a 6-fold increase in the frequency of carbenicillin resistant clones. Subcloning and sequence analysis showed that, besides β-lactamases, efflux pumps are not only able contribute to carbenicillin resistance but may in fact be sufficient by themselves to convey carbenicillin resistance.
Back to basics: pBR322 and protein expression systems in E. coli.

PubMed

Balbás, Paulina; Bolívar, Francisco

2004-01-01

The extensive variety of plasmid-based expression systems in E. coli resulted from the fact that there is no single strategy for achieving maximal expression of every cloned gene. Although a number of strategies have been implemented to deal with problems associated to gene transcription and translation, protein folding, secretion, location, posttranslational modifications, particularities of different strains, and the like and more integrated processes have been developed, the basic plasmid-borne elements and their interaction with the particular host strain will influence the overall expression system and final productivity. Plasmid vector pBR322 is a well-established multipurpose cloning vector in laboratories worldwide, and a large number of derivatives have been created for specific applications and research purposes, including gene expression in its natural host, E. coli, and few other bacteria. The early characterization of the molecule, including its nucleotide sequence, replication and maintenance mechanisms, and determination of its coding regions, accounted for its success, not only as a universal cloning vector, but also as a provider of genes and an origin of replication for other intraspecies vectors. Since the publication of the aforementioned reviews, novel discoveries pertaining to these issues have appeared in the literature that deepen the understanding of the plasmid's features, behavior, and impact in gene expression systems, as well as some important strain characteristics that affect plasmid replication and stability. The objectives of this review include updating and discussing the new information about (1) the replication and maintenance of pBR322; (2) the host-related modulation mechanisms of plasmid replication; (3) the effects of growth rate on replication control, stability, and recombinant gene expression; (4) ways for plasmid amplification and elimination. Finally, (5) a summary of novel ancillary studies about pBR322 is presented.
Optimised 'on demand' protein arraying from DNA by cell free expression with the 'DNA to Protein Array' (DAPA) technology.

PubMed

Schmidt, Ronny; Cook, Elizabeth A; Kastelic, Damjana; Taussig, Michael J; Stoevesandt, Oda

2013-08-02

We have previously described a protein arraying process based on cell free expression from DNA template arrays (DNA Array to Protein Array, DAPA). Here, we have investigated the influence of different array support coatings (Ni-NTA, Epoxy, 3D-Epoxy and Polyethylene glycol methacrylate (PEGMA)). Their optimal combination yields an increased amount of detected protein and an optimised spot morphology on the resulting protein array compared to the previously published protocol. The specificity of protein capture was improved using a tag-specific capture antibody on a protein repellent surface coating. The conditions for protein expression were optimised to yield the maximum amount of protein or the best detection results using specific monoclonal antibodies or a scaffold binder against the expressed targets. The optimised DAPA system was able to increase by threefold the expression of a representative model protein while conserving recognition by a specific antibody. The amount of expressed protein in DAPA was comparable to those of classically spotted protein arrays. Reaction conditions can be tailored to suit the application of interest. DAPA represents a cost effective, easy and convenient way of producing protein arrays on demand. The reported work is expected to facilitate the application of DAPA for personalized medicine and screening purposes. Copyright © 2013 Elsevier B.V. All rights reserved.
Real-time yield estimation based on deep learning

NASA Astrophysics Data System (ADS)

Rahnemoonfar, Maryam; Sheppard, Clay

2017-05-01

Crop yield estimation is an important task in product management and marketing. Accurate yield prediction helps farmers to make better decision on cultivation practices, plant disease prevention, and the size of harvest labor force. The current practice of yield estimation based on the manual counting of fruits is very time consuming and expensive process and it is not practical for big fields. Robotic systems including Unmanned Aerial Vehicles (UAV) and Unmanned Ground Vehicles (UGV), provide an efficient, cost-effective, flexible, and scalable solution for product management and yield prediction. Recently huge data has been gathered from agricultural field, however efficient analysis of those data is still a challenging task. Computer vision approaches currently face diffident challenges in automatic counting of fruits or flowers including occlusion caused by leaves, branches or other fruits, variance in natural illumination, and scale. In this paper a novel deep convolutional network algorithm was developed to facilitate the accurate yield prediction and automatic counting of fruits and vegetables on the images. Our method is robust to occlusion, shadow, uneven illumination and scale. Experimental results in comparison to the state-of-the art show the effectiveness of our algorithm.
Free range and deep litter poultry production systems: effect on performance, carcass yield and meat composition of cockerel chickens.

PubMed

Sogunle, Olajide Mark; Olaniyi, Olagoke Ayobami; Egbeyale, Lawrence Tokunbo; Akinola, Olufemi Sunday; Shittu, Taofeek A; Abiola, Samuel Soladoye; Ladokun, Abimbola O; Sobayo, Richard Abayomi

2013-01-01

This study was carried out on 150 cockerel chickens each of Harco Black and Novogen strains to determine their performance, carcass yield and meat composition on free range and deep litter production systems. The birds were brooded for 4 weeks and thereafter allotted to the different production systems for a period of 12 weeks. Each production system was allotted 150 chicks (75 chicks per strain) with three replicates of 25 chicks. The birds on deep litter production system were fed ad libitum while each bird on free range was fed 50 % of its daily feed requirement. On the 84 th day, a total of 36 birds were randomly selected for analysis of the carcass yield and meat composition. The data generated were subjected to a two-way analysis of variance in a 2 × 2 factorial experimental arrangement. Novogen strain consumed less feed (P < 0.05) on free range and had the best feed/gain (2.72). A higher (P < 0.05) shear force value (3.74 N) was obtained in the thigh muscle for birds on free range. The tibia proximal length and breadth, and tibia distal length and breadth were significantly (P < 0.05) affected by the production systems and strains. On free range, Harco black had more meat (85.69 g) than bone (18.07 g) in the breast while Novogen had the lowest meat/bone (2.38). Conclusively, Novogen strain should be raised on free range for a better performance in terms of feed/gain, but for higher meat composition, Harco black is a better strain.

Z{gamma}{gamma}{gamma} {yields} 0 Processes in SANC

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

Bardin, D. Yu., E-mail: bardin@nu.jinr.ru; Kalinovskaya, L. V., E-mail: kalinov@nu.jinr.ru; Uglov, E. D., E-mail: corner@nu.jinr.ru

2013-11-15

We describe the analytic and numerical evaluation of the {gamma}{gamma} {yields} {gamma}Z process cross section and the Z {yields} {gamma}{gamma}{gamma} decay rate within the SANC system multi-channel approach at the one-loop accuracy level with all masses taken into account. The corresponding package for numeric calculations is presented. For checking of the results' correctness we make a comparison with the other independent calculations.
L-arginine mediated renaturation enhances yield of human, α6 type IV collagen non-collagenous domain from bacterial inclusion bodies

PubMed Central

Gunda, Venugopal; Boosani, Chandra Shekhar; Verma, Raj Kumar; Guda, Chittibabu; Akul Sudhakar, Yakkanti

2012-01-01

The anti-angiogenic, carboxy terminal non-collagenous domain (NC1) derived from human Collagen type IV alpha 6 chain, [α6(IV)NC1] or hexastatin, was earlier obtained using different recombinant methods of expression in bacterial systems. However, the effect of L-arginine mediated renaturation in enhancing the relative yields of this protein from bacterial inclusion bodies has not been evaluated. In the present study, direct stirring and on-column renaturation methods using L-arginine and different size exclusion chromatography matrices were applied for enhancing the solubility in purifying the recombinant α6(IV)NC1 from bacterial inclusion bodies. This methodology enabled purification of higher quantities of soluble protein from inclusion bodies, which inhibited endothelial cell proliferation, migration and tube formation. Thus, the scope for L-arginine mediated renaturation in obtaining higher yields of soluble, biologically active NC1 domain from bacterial inclusion bodies was evaluated. PMID:22512648
L-arginine mediated renaturation enhances yield of human, α6 Type IV collagen non-collagenous domain from bacterial inclusion bodies.

PubMed

Gunda, Venugopal; Boosani, Chandra Shekhar; Verma, Raj Kumar; Guda, Chittibabu; Sudhakar, Yakkanti Akul

2012-10-01

The anti-angiogenic, carboxy terminal non-collagenous domain (NC1) derived from human Collagen type IV alpha 6 chain, [α6(IV)NC1] or hexastatin, was earlier obtained using different recombinant methods of expression in bacterial systems. However, the effect of L-arginine mediated renaturation in enhancing the relative yields of this protein from bacterial inclusion bodies has not been evaluated. In the present study, direct stirring and on-column renaturation methods using L-arginine and different size exclusion chromatography matrices were applied for enhancing the solubility in purifying the recombinant α6(IV)NC1 from bacterial inclusion bodies. This methodology enabled purification of higher quantities of soluble protein from inclusion bodies, which inhibited endothelial cell proliferation, migration and tube formation. Thus, the scope for L-arginine mediated renaturation in obtaining higher yields of soluble, biologically active NC1 domain from bacterial inclusion bodies was evaluated.
Expression of hygromycin B resistance in oyster culinary-medicinal mushroom, Pleurotus ostreatus (Jacq.:Fr.)P. Kumm. (higher Basidiomycetes) using three gene expression systems.

PubMed

Dong, Xiaoya; Zhang, Ke; Gao, Yuqian; Qi, Yuancheng; Shen, Jinwen; Qiu, Liyou

2012-01-01

Three hygromycin B phosphotransferase (hph) gene expression systems for culinary-medicinal Oyster mushroom, Pleurotus ostreatus, plasmid pSHC, pAN7-1, and pBHt1 were evaluated through PEG/CaCl(2)-mediated protoplast transformation. Plasmid pSHC is a newly constructed hph gene expression system, composed of Escherichia coli hph gene, the P. ostreatus sdi promoter, and the CaMV35S terminator. The vector pAN7-1 was commonly used for integrative transformation in filamentous fungi. Plasmid pBHtl is a T-DNA binary vector, usually introduced into fungi by Agrobacterium-mediated transformation. The results showed that plasmids pSHC, pAN7-1, and pBHt1 were all integrated into the host chromosomes and expressed hygromycin B resistance in P. ostreatus. pAN7-1 had the highest transformation efficiency and hph gene expression level, pSHC the second, and pBHt1 the lowest. Growth rates of the transformants on plates containing hygromycin B were in correspondence with their hph gene expression levels. To our knowledge, this is the first report on integrated transformation of plasmid pAN7-1 and pBHt1 in P. ostreatus.
Interaction between sympathetic nervous system and renin angiotensin system on MMPs expression in juvenile rat aorta.

PubMed

Dab, Houcine; Hachani, Rafik; Hodroj, Wassim; Sakly, Mohsen; Bricca, Giampiero; Kacem, Kamel

2011-09-01

The aim of our present study is to investigate the interaction between angiotensin II (ANG II) and sympathetic nervous system (SNS) on matrix metalloproteinase MMP-2 and MMP-9 expression and activity in juvenile rat aorta under normal conditions. Sympathectomy with guanethidine and blockade of the ANG II receptors (AT1R) by losartan were performed alone or in combination on new-born rats. mRNA, protein expression and activity of MMP-2 and MMP-9 were examined by Q-RT-PCR, immunoblotting and zymography, respectively. MMP-2 mRNA and protein amount were decreased after sympathectomy or AT1R blockade and an additive effect was observed after combined treatment. However, MMP-9 expression was reduced to the same level in the three treated groups. There were some detectable gelatinolytic activity of the MMPs in both control and treated rats. We concluded that ANG II stimulates directly and indirectly (via sympathostimulator pathway) the MMP-2 expression but seems unable to affect MMP-9 expression through direct pathway. Combined inhibition of SNS and ANG II were more efficient than a single inhibition in reducing MMP amounts in rat vessels.
Plant expression systems, a budding way to confront chikungunya and Zika in developing countries?

PubMed Central

Cardona-Ospina, Jaime A.; Sepúlveda-Arias, Juan C.; Mancilla, L.; Gutierrez-López, Luis G.

2016-01-01

Plant expression systems could be used as biofactories of heterologous proteins that have the potential to be used with biopharmaceutical aims and vaccine design. This technology is scalable, safe and cost-effective and it has been previously proposed as an option for vaccine and protein pharmaceutical development in developing countries. Here we present a proposal of how plant expression systems could be used to address Zika and chikungunya outbreaks through development of vaccines and rapid diagnostic kits. PMID:27781090
ADAM17 limits the expression of CSF1R on murine hematopoietic progenitors

PubMed Central

Becker, Amy M.; Walcheck, Bruce; Bhattacharya, Deepta

2014-01-01

All-lymphoid progenitors (ALPs) yield few myeloid cells in vivo, but readily generate such cells in vitro. The basis for this difference remains unknown. We hypothesized that ALPs limit responsiveness to in vivo concentrations of myeloid-promoting cytokines by reducing expression of the corresponding receptors, potentially through post-transcriptional mechanisms. Consistent with such a mechanism, ALPs express higher levels of Csf1r transcripts than their upstream precursors, yet show limited cell surface protein expression of CSF1R. ALPs and other hematopoietic progenitors deficient in ADAM17, a metalloprotease that can cleave CSF1R, display elevated cell surface CSF1R expression. Adam17−/− ALPs, however, fail to yield myeloid cells upon transplantation into irradiated recipients. Moreover, Adam17−/− ALPs yield fewer macrophages in vitro than control ALPs at high concentrations of M-CSF. Mice with hematopoietic-specific deletion of Adam17 have grossly normal numbers of myeloid and lymphoid progenitors and mature cells in vivo. These data demonstrate that ADAM17 limits CSF1R protein expression on hematopoietic progenitors, but that compensatory mechanisms prevent elevated CSF1R levels from altering lymphoid progenitor potential. PMID:25308957
Heterologous Expression of Membrane Proteins: Choosing the Appropriate Host

PubMed Central

Pochon, Nathalie; Dementin, Sébastien; Hivin, Patrick; Boutigny, Sylvain; Rioux, Jean-Baptiste; Salvi, Daniel; Seigneurin-Berny, Daphné; Richaud, Pierre; Joyard, Jacques; Pignol, David; Sabaty, Monique; Desnos, Thierry; Pebay-Peyroula, Eva; Darrouzet, Elisabeth; Vernet, Thierry; Rolland, Norbert

2011-01-01

Background Membrane proteins are the targets of 50% of drugs, although they only represent 1% of total cellular proteins. The first major bottleneck on the route to their functional and structural characterisation is their overexpression; and simply choosing the right system can involve many months of trial and error. This work is intended as a guide to where to start when faced with heterologous expression of a membrane protein. Methodology/Principal Findings The expression of 20 membrane proteins, both peripheral and integral, in three prokaryotic (E. coli, L. lactis, R. sphaeroides) and three eukaryotic (A. thaliana, N. benthamiana, Sf9 insect cells) hosts was tested. The proteins tested were of various origins (bacteria, plants and mammals), functions (transporters, receptors, enzymes) and topologies (between 0 and 13 transmembrane segments). The Gateway system was used to clone all 20 genes into appropriate vectors for the hosts to be tested. Culture conditions were optimised for each host, and specific strategies were tested, such as the use of Mistic fusions in E. coli. 17 of the 20 proteins were produced at adequate yields for functional and, in some cases, structural studies. We have formulated general recommendations to assist with choosing an appropriate system based on our observations of protein behaviour in the different hosts. Conclusions/Significance Most of the methods presented here can be quite easily implemented in other laboratories. The results highlight certain factors that should be considered when selecting an expression host. The decision aide provided should help both newcomers and old-hands to select the best system for their favourite membrane protein. PMID:22216205
Effect of Irrigation to Winter Wheat on the Radiation Use Efficiency and Yield of Summer Maize in a Double Cropping System

PubMed Central

Quanqi, Li; Yuhai, Chen; Xunbo, Zhou; Songlie, Yu; Changcheng, Guo

2012-01-01

In north China, double cropping of winter wheat and summer maize is a widely adopted agricultural practice, and irrigation is required to obtain a high yield from winter wheat, which results in rapid aquifer depletion. In this experiment conducted in 2001-2002, 2002-2003, and 2004-2005, we studied the effects of irrigation regimes during specific winter wheat growing stage with winter wheat and summer maize double cropping systems; we measured soil moisture before sowing (SMBS), the photosynthetic active radiation (PAR) capture ratio, grain yield, and the radiation use efficiency (RUE) of summer maize. During the winter wheat growing season, irrigation was applied at the jointing, heading, or milking stage, respectively. The results showed that increased amounts of irrigation and irrigation later in the winter wheat growing season improved SMBS for summer maize. The PAR capture ratio significantly (LSD, P < 0.05) increased with increased SMBS, primarily in the 3 spikes leaves. With improved SMBS, both the grain yield and RUE increased in all the treatments. These results indicate that winter wheat should be irrigated in later stages to achieve reasonable grain yield for both crops. PMID:22654613
Enhanced Sucrose Loading Improves Rice Yield by Increasing Grain Size.

PubMed

Wang, Liang; Lu, Qingtao; Wen, Xiaogang; Lu, Congming

2015-12-01

Yield in cereals is a function of grain number and size. Sucrose (Suc), the main carbohydrate product of photosynthesis in higher plants, is transported long distances from source leaves to sink organs such as seeds and roots. Here, we report that transgenic rice plants (Oryza sativa) expressing the Arabidopsis (Arabidopsis thaliana) phloem-specific Suc transporter (AtSUC2), which loads Suc into the phloem under control of the phloem protein2 promoter (pPP2), showed an increase in grain yield of up to 16% relative to wild-type plants in field trials. Compared with wild-type plants, pPP2::AtSUC2 plants had larger spikelet hulls and larger and heavier grains. Grain filling was accelerated in the transgenic plants, and more photoassimilate was transported from the leaves to the grain. In addition, microarray analyses revealed that carbohydrate, amino acid, and lipid metabolism was enhanced in the leaves and grain of pPP2::AtSUC2 plants. Thus, enhancing Suc loading represents a promising strategy to improve rice yield to feed the global population. © 2015 American Society of Plant Biologists. All Rights Reserved.
Soviet test yields

NASA Astrophysics Data System (ADS)

Vergino, Eileen S.

Soviet seismologists have published descriptions of 96 nuclear explosions conducted from 1961 through 1972 at the Semipalatinsk test site, in Kazakhstan, central Asia [Bocharov et al., 1989]. With the exception of releasing news about some of their peaceful nuclear explosions (PNEs) the Soviets have never before published such a body of information.To estimate the seismic yield of a nuclear explosion it is necessary to obtain a calibrated magnitude-yield relationship based on events with known yields and with a consistent set of seismic magnitudes. U.S. estimation of Soviet test yields has been done through application of relationships to the Soviet sites based on the U.S. experience at the Nevada Test Site (NTS), making some correction for differences due to attenuation and near-source coupling of seismic waves.
Effect of DNA sequence of Fab fragment on yield characteristics and cell growth of E. coli.

PubMed

Kulmala, Antti; Huovinen, Tuomas; Lamminmäki, Urpo

2017-06-19

Codon usage is one of the factors influencing recombinant protein expression. We were interested in the codon usage of an antibody Fab fragment gene exhibiting extreme toxicity in the E. coli host. The toxic synthetic human Fab gene contained domains optimized by the "one amino acid-one codon" method. We redesigned five segments of the Fab gene with a "codon harmonization" method described by Angov et al. and studied the effects of these changes on cell viability, Fab yield and display on filamentous phage using different vectors and bacterial strains. The harmonization considerably reduced toxicity, increased Fab expression from negligible levels to 10 mg/l, and restored the display on phage. Testing the impact of the individual redesigned segments revealed that the most significant effects were conferred by changes in the constant domain of the light chain. For some of the Fab gene variants, we also observed striking differences in protein yields when cloned from a chloramphenicol resistant vector into an identical vector, except with ampicillin resistance. In conclusion, our results show that the expression of a heterodimeric secretory protein can be improved by harmonizing selected DNA segments by synonymous codons and reveal additional complexity involved in heterologous protein expression.
Milk yield and genomewide expression profiling in the mammary gland of beef primiparous cows in response to the dietary management during the pre- and postweaning periods.

PubMed

Dervishi, E; Blanco, M; Rodríguez-Sánchez, J A; Sanz, A; Calvo, J H; Casasús, I

2017-10-01

Accelerated growth programs during prepubertal periods have been promoted to advance the first calving of beef heifers. The objectives of the present study were to evaluate nutrition-induced changes on first lactation milk yield and composition and on gene expression of the mammary gland in Parda de Montaña primiparous cows. Female calves ( = 16) were involved in a 2 × 2 factorial experiment. In the preweaning period (PRE-W; 0-6 mo), female calves were either fed a creep feed supplement (Creep) or fed only their dam's milk (Control). In the postweaning period (POST-W; 6-15 mo), heifers received either a high-energy diet (91.7 MJ/d) or a moderate-energy diet (79.3 MJ/d). All the heifers were managed together from breeding (15 mo) to the end of their first lactation (32 mo). Animal performance; milk production and quantity during the first lactation; plasma glucose, IGF-I, and leptin concentrations; and RNA samples from the mammary gland at the end of the first lactation of the primiparous cows (32 mo) were analyzed. The BW and ADG of the primiparous cow during its first lactation were not different among treatments; however, creep feeding during PRE-W reduced milk production ( < 0.01), milk CP, crude fat, lactose, nonfat solids, and casein content throughout lactation and increased somatic cell count in the third ( < 0.05) and fourth month of lactation ( < 0.10). The energy level during the POST-W had no effect on milk production and quality. Gene expression in the mammary gland was affected by the diet in the PRE-W and POST-W, with the PRE-W diet having the greatest impact. During the PRE-W, creep feeding resulted in upregulation of genes related to immune response and chemokine activity, suggesting that these animals might be in a compromised immune status. Therefore, this strategy would not be recommendable; meanwhile, increasing the energy level in the diet during the POST-W would be recommendable, because it had no deleterious effects on milk yield and
Measurement of liner slips, milking time, and milk yield.

PubMed

O'Callaghan, E J

1996-03-01

Liner slip or rapid air leakage past the mouthpiece of the milking machine liner is related to high rates of new cases of mastitis. A real time technique was developed to monitor the air flow into the milking machine cluster during liner slips as well as to monitor milking time and milk yield using a commercial type pipeline milking system. The air flow into the cluster was measured by recording the pressure differences across an orifice plate placed in the air bypass of an air-milk separator using a differential pressure transducer. Milk yield was recorded by counting the number of milk releases from an electronic milk meter. The release solenoids of the milk meter were linked to a computer. The start and end of milking were manually recorded by switching a two-pole switch connected to a digital input card on the computer, which was programmed to record air flow, milk yield, and milking time. Milk yield, milking time, and air flows during liner slips were recorded simultaneously at each milking unit in an 11-unit herringbone parlor. The system was tested with an experiment with a 4 x 4 Latin square design using four treatments (clusters) and four treatment groups (22 cows per group).
A high-level prokaryotic expression system: synthesis of human interleukin 1 alpha and its receptor antagonist.

PubMed

Birikh, K R; Lebedenko, E N; Boni, I V; Berlin, Y A

1995-10-27

Synthetic intronless genes, coding for human interleukin 1 alpha (IL 1 alpha) and interleukin 1 receptor antagonist (IL1ra), have been expressed efficiently in a specially designed prokaryotic vector, pGMCE (a pGEM1 derivative), where the target gene forms the second part of a two-cistron system. The first part of the system is a translation enhancer-containing mini-cistron, whose termination codon overlaps the start codon of the target gene. In the case of the IL1 alpha gene, the high expression level is largely due to the direct efficient translation initiation at the second cistron, whereas with the IL1ra gene in the same system, the proximal translation initiation region (TIR) provides a high level of coupled expression of the target gene. Thus, pGMCE is a potentially versatile vector for direct prokaryotic expression.
Impact of heterozygosity and heterogeneity on cotton lint yield stability: II. Lint yield components

USDA-ARS?s Scientific Manuscript database

In order to determine which yield components may contribute to yield stability, an 18-environment field study was undertaken to observe the mean, standard deviation (SD), and coefficient of variation (CV) for cotton lint yield components in population types that differed for lint yield stability. Th...
Automated Structure- and Sequence-Based Design of Proteins for High Bacterial Expression and Stability.

PubMed

Goldenzweig, Adi; Goldsmith, Moshe; Hill, Shannon E; Gertman, Or; Laurino, Paola; Ashani, Yacov; Dym, Orly; Unger, Tamar; Albeck, Shira; Prilusky, Jaime; Lieberman, Raquel L; Aharoni, Amir; Silman, Israel; Sussman, Joel L; Tawfik, Dan S; Fleishman, Sarel J

2016-07-21

Upon heterologous overexpression, many proteins misfold or aggregate, thus resulting in low functional yields. Human acetylcholinesterase (hAChE), an enzyme mediating synaptic transmission, is a typical case of a human protein that necessitates mammalian systems to obtain functional expression. We developed a computational strategy and designed an AChE variant bearing 51 mutations that improved core packing, surface polarity, and backbone rigidity. This variant expressed at ∼2,000-fold higher levels in E. coli compared to wild-type hAChE and exhibited 20°C higher thermostability with no change in enzymatic properties or in the active-site configuration as determined by crystallography. To demonstrate broad utility, we similarly designed four other human and bacterial proteins. Testing at most three designs per protein, we obtained enhanced stability and/or higher yields of soluble and active protein in E. coli. Our algorithm requires only a 3D structure and several dozen sequences of naturally occurring homologs, and is available at http://pross.weizmann.ac.il. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.
Bovine papillomavirus type 4 L1 gene transfection in a Drosophila S2 cell expression system: absence of L1 protein expression

PubMed Central

Góes, Luiz Gustavo Bentim; de Freitas, Antonio Carlos; Ferraz, Oilita Pereira; Rieger, Tania Tassinari; dos Santos, José Ferreira; Pereira, Alexandre; Beçak, Willy; Lindsey, Charles J.; de Cassia Stocco, Rita

2008-01-01

The development of a bovine papillomavirus (BPV) vaccine is an outstanding challenge. BPV protein L1 gene transfection in the Drosophila melanogaster S2 cell expression system failed to produce L1 protein notwithstanding correct L1 gene insertion. Severe genetic inbalance in the host cell line, including cytogenetic alterations, may account for the lack of protein expression. PMID:24031166
A Green-Light-Responsive System for the Control of Transgene Expression in Mammalian and Plant Cells.

PubMed

Chatelle, Claire; Ochoa-Fernandez, Rocio; Engesser, Raphael; Schneider, Nils; Beyer, Hannes M; Jones, Alex R; Timmer, Jens; Zurbriggen, Matias D; Weber, Wilfried

2018-05-18

The ever-increasing complexity of synthetic gene networks and applications of synthetic biology requires precise and orthogonal gene expression systems. Of particular interest are systems responsive to light as they enable the control of gene expression dynamics with unprecedented resolution in space and time. While broadly used in mammalian backgrounds, however, optogenetic approaches in plant cells are still limited due to interference of the activating light with endogenous photoreceptors. Here, we describe the development of the first synthetic light-responsive system for the targeted control of gene expression in mammalian and plant cells that responds to the green range of the light spectrum in which plant photoreceptors have minimal activity. We first engineered a system based on the light-sensitive bacterial transcription factor CarH and its cognate DNA operator sequence CarO from Thermus thermophilus to control gene expression in mammalian cells. The system was functional in various mammalian cell lines, showing high induction (up to 350-fold) along with low leakiness, as well as high reversibility. We quantitatively described the systems characteristics by the development and experimental validation of a mathematical model. Finally, we transferred the system into A. thaliana protoplasts and demonstrated gene repression in response to green light. We expect that this system will provide new opportunities in applications based on synthetic gene networks and will open up perspectives for optogenetic studies in mammalian and plant cells.
Universality and depinning models for plastic yield in amorphous materials

NASA Astrophysics Data System (ADS)

Budrikis, Zoe; Fernandez Castellano, David; Sandfeld, Stefan; Zaiser, Michael; Zapperi, Stefano

Plastic yield in amorphous materials occurs as a result of complex collective dynamics of local reorganizations, which gives rise to rich phenomena such as strain localization, intermittent dynamics and power-law distributed avalanches. While such systems have received considerable attention, both theoretical and experimental, controversy remains over the nature of the yielding transition. We present a new fully-tensorial coarsegrained model in 2D and 3D, and demonstrate that the exponents describing avalanche distributions are universal under a variety of loading conditions, system dimensionality and size, and boundary conditions. Our results show that while depinning-type models in general are apt to describe the system, mean field depinning models are not.

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