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971.
Polyclonal antibodies, as well as monoclonal antibodies are efficacious in providing protective immunity against Francisella tularensis. This study demonstrates the application of phage display libraries for the construction of monoclonal antibodies against
F. tularensis. Novel single-chain fragment variable (scFv) antibodies were generated against a whole bacterial lysate of F. tularensis live vaccine strain using the human single fold scFv libraries I (Tomlinson I + J). A total of 20 clones reacted with the
bacterial cell lysate. Further, the library contains two clones responsive to recombinant lipoprotein FTT1103Δsignal (F. tularensis subsp. tularensis Schu S4), which was constructed without a signal sequence. These positively-binding scFvs were evaluated by scFv-phage enzyme-linked
immunosorbent assay (ELISA). Then, positive scFvs were expressed in a soluble form in Escherichia coli HB2151 and tested for positive scFvs by using scFv-ELISA. 相似文献
972.
Phosphoproteomics is increasingly used to address a wide range of biological questions. However, despite some success, techniques for phosphoproteomics are not without challenges. Phosphoproteins are present in cells in low abundance relative to their unphosphorylated counterparts; therefore phosphorylated proteins (or phosphopeptides after protein digestion) are rarely detected in standard shotgun proteomics experiments. Thus, extraction of phosphorylated polypeptides from complex mixtures is a critical step in the success of phosphoproteomics experiments. Intense research over the last decade has resulted in the development of powerful techniques for phosphopeptide enrichment prior to analysis by mass spectrometry. Here, we review how the development of IMAC, MOAC, chemical derivatization and antibody affinity purification and chromatography is contributing to the evolution of phosphoproteomics techniques. Although further developments are needed for the technology to reach maturity, current state-of-the-art techniques can already be used as powerful tools for biological research. 相似文献
973.
The reserves of fossil-based fuels, which currently seem sufficient to meet the global demands, is inevitably on the verge of exhaustion. Contemporary raw material for alternate fuel like biodiesel is usually edible plant commodity oils, whose increasing public consumption rate raises the need of finding a non-edible and fungible alternate oil source. In this quest, single cell oils (SCO) from oleaginous yeasts and fungi can provide a sustainable alternate of not only functional but also valuable (polyunsaturated fatty acids (PUFA)-rich) lipids. Researches are been increasingly driven towards increasing the SCO yield in order to realize its commercial importance. However, bulk requirement of expensive synthetic carbon substrate, which inflates the overall SCO production cost, is the major limitation towards complete acceptance of this technology. Even though substrate cost minimization could make the SCO production profitable is uncertain, it is still essential to identify suitable cheap and abundant substrates in an attempt to potentially reduce the overall process economy. One of the most sought-after in-expensive carbon reservoirs, agro-industrial wastes, can be an attractive replacement to expensive synthetic carbon substrates in this regard. The present review assess these possibilities referring to the current experimental investigations on oleaginous yeasts, and fungi reported for conversion of agro-industrial feedstocks into triacylglycerols (TAGs) and PUFA-rich lipids. Multiple associated factors regulating lipid accumulation utilizing such substrates and impeding challenges has been analyzed. The review infers that production of bulk oil in combination to high-value fatty acids, co-production strategies for SCO and different microbial metabolites, and reutilization and value addition to spent wastes could possibly leverage the high operating costs and help in commencing a successful biorefinery. Rigorous research is nevertheless required whether it is PUFA-rich oil production (for competing with algal omega oils) or neutral bulk oil production (for overcoming yield limitations and managing process economy) to establish this potential source as future resource. 相似文献
974.
Chronic Administration of Mood Stabilizers Upregulates BDNF and Bcl-2 Expression Levels in Rat Frontal Cortex 总被引:1,自引:0,他引:1
Brain-derived neurotrophic factor (BDNF) and B-cell lymphoma-2 (Bcl-2) proteins are neuroprotective factors involved in neuronal
signaling, survival and plasticity. Both can be regulated by cyclic AMP response element binding (CREB) protein. Decreased
levels of BDNF and Bcl-2 are implicated in the pathogenesis of bipolar disorder. The present study investigated whether chronically
administered mood stabilizers would increase BDNF and/or Bcl-2 levels in rat brain. Real time RT-PCR, sandwich ELISA and Western
blotting were used to measure BDNF and Bcl-2 mRNA and protein levels in the frontal cortex of rats chronically administered
carbamazepine (CBZ) or lamotrigine (LTG) to produce plasma concentrations therapeutically relevant to bipolar disorder. Chronic
CBZ and LTG significantly increased BDNF and Bcl-2 mRNA and protein levels in the frontal cortex. A common mechanism of action
of mood stabilizers in the treatment of bipolar disorder may involve neuroprotection mediated by upregulation of brain BDNF
and Bcl-2 expression. 相似文献
975.
Phytoplankton morphological response to the underwater light conditions in a vegetated wetland 总被引:2,自引:3,他引:2
This study analyses the influence of the underwater light climate on the morphometric characteristics of the phytoplankton
at the population and community levels. The differences in light conditions across the floodplain were mainly defined by the
patchiness of floating macrophytes and humic acids concentration. A morphometric response at the community level to the underwater
PAR was registered. Sites with strong light constraints were characterised by non-flagellated organisms or with a small proportion
of unicellular flagellates. Short organisms (<10 μm) with a unit volume of less than 1,000 μm3 and a high surface:volume ratio (S/V >2) were the morphotypes related to poorly illuminated environments. Moreover, the organisms
showed forms more slender under these limiting conditions. This pattern was different to that registered in well-illuminated
sites where longer and larger organisms, with a smaller S/V and frequently flagellated, coexisted with the previously mentioned
organisms. The autotrophic picoplankton, the smallest phytoplankton fraction, revealed lower abundances at sites with higher
humic substances. Short term morphological changes were additionally studied for the dominant species by means of mesocosm
experiments simulating different light climates. Intraspecific morphological plasticity was observed with respect to the filament
length and the vacuolization of cells.
Electronic Supplementary Material Supplementary material is available for this article at and is available to authorized users. 相似文献
976.
Gluconic acid (GA) is a multifunctional carbonic acid regarded as a bulk chemical in the food, feed, beverage, textile, pharmaceutical,
and construction industries. The favored production process is submerged fermentation by Aspergillus niger utilizing glucose as a major carbohydrate source, which accompanied product yield of 98%. However, use of GA and its derivatives
is currently restricted because of high prices: about US$ 1.20–8.50/kg. Advancements in biotechnology such as screening of
microorganisms, immobilization techniques, and modifications in fermentation process for continuous fermentation, including
genetic engineering programmes, could lead to cost-effective production of GA. Among alternative carbohydrate sources, sugarcane
molasses, grape must show highest GA yield of 95.8%, and banana must may assist reducing the overall cost of GA production.
These methodologies would open new markets and increase applications of GA.
Authors’ contributions OVS and RK are the sole contributors of this original review article. This review is based upon the published research in
the area of gluconic acid fermentation. 相似文献
977.
Loc Van Nguyen Ryoji Takahashi Stephen Mwangi Githiri Tito O. Rodriguez Nobuko Tsutsumi Sayuri Kajihara Takasi Sayama Masao Ishimoto Kyuya Harada Keisuke Suematsu Tomomi Abiko Toshihiro Mochizuki 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(4):743-755
Key message
Greatest potential, QTLs for hypoxia and waterlogging tolerance in soybean roots were detected using a new phenotypic evaluation method.Abstract
Waterlogging is a major environmental stress limiting soybean yield in wet parts of the world. Root development is an important indicator of hypoxia tolerance in soybean. However, little is known about the genetic control of root development under hypoxia. This study was conducted to identify quantitative trait loci (QTLs) responsible for root development under hypoxia. Recombinant inbred lines (RILs) developed from a cross between a hypoxia-sensitive cultivar, Tachinagaha, and a tolerant landrace, Iyodaizu, were used. Seedlings were subjected to hypoxia, and root development was evaluated with the value change in root traits between after and before treatments. We found 230 polymorphic markers spanning 2519.2 cM distributed on all 20 chromosomes (Chrs.). Using these, we found 11 QTLs for root length (RL), root length development (RLD), root surface area (RSA), root surface area development (RSAD), root diameter (RD), and change in average root diameter (CARD) on Chrs. 11, 12, 13 and 14, and 7 QTLs for hypoxia tolerance of these root traits. These included QTLs for RLD and RSAD between markers Satt052 and Satt302 on Chr. 12, which are important markers of hypoxia tolerance in soybean; those QTLs were stable between 2 years. To validate the QTLs, we developed a near-isogenic line with the QTL region derived from Iyodaizu. The line performed well under both hypoxia and waterlogging, suggesting that the region contains one or more genes with large effects on root development. These findings may be useful for fine mapping and positional cloning of gene responsible for root development under hypoxia.978.
979.
Radiological workers sensitivity to 50 Hz pulsed magnetic fields: preliminary results 总被引:1,自引:0,他引:1
In the present study the effect of extremely low frequency pulsed magnetic fields (PMF) was evaluated in lymphocyte cultures from 12 subjects occupationally exposed to low doses of ionising radiations. The PMF signal characteristics were repetition frequency 50 Hz, triangular shape, rise time about 1.2 ms and peak intensity 2.5 mT. The cytokinesis-block technique was employed to evaluate genotoxicity and cytotoxicity in terms of micronucleus frequency and cell proliferation, respectively. When PMF-exposed cultures were compared with their respective controls, a slight but statistically significant increase was detected in both the biological parameters investigated ( p<0.05). The results obtained suggest a possible role of specific employments involving exposure to ionising radiation, in the risk associated with electromagnetic field exposure. 相似文献
980.
A viable option for increasing nitrogen (N) use efficiency and mitigation of negative impacts of N on the environment is to capitalize on multi-element interactions through implementation of nutrient management programs that provide balanced nutrition. Numerous studies have demonstrated the immediate efficacy of this approach in the developing regions like China and India as well as developed countries in North America. Based on 241 site-years of experiments in these countries, the first-year N recovery efficiency (RE) for the conventional or check treatments averaged 21% while the balanced treatments averaged 54% RE, for an average increase of 33% in RE due to balanced nutrition. Effective policies to promote adoption are most likely those that enable site-specific approaches to nutrient management decisions rather than sweeping, nation-wide incentives supporting one nutrient over another. Local farmers, advisers and officials need to be empowered with tools and information to help them define necessary changes in practices to create more balanced nutrient management. 相似文献