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961.
Expression of single-chain variable fragment (scFv) antibodies on the surface of bacteriophage is widely used to prepare antibodies with pre-defined specificities. A phage antibody library containing the gene for scFv antibody against Hepatitis C virus core protein was panned with core protein immobilized on microtiter plate wells. After five rounds of panning 60 phage clones specific to core protein were obtained and one selected clone was sequenced. It was found that the specifically detected antigen consists of 774bp and is capable of encoding 257 amino acids in the patients but not in healthy persons. 相似文献
962.
963.
Hawon Lee Dae Haeng Cho Yong Hwan Kim Soo-Jeong Shin Sung Bong Kim Sung Ok Han Jinwon Lee Seung Wook Kim Chulhwan Park 《Biotechnology and Bioprocess Engineering》2011,16(4):755-760
The hydrolysis which converts polysaccharides to the fermentable sugars for yeast’s lingocellulosic ethanol production also
generates byproducts which inhibit the ethanol production. To investigate the extent to which inhibitory compounds affect
yeast’s growth and ethanol production, fermentations by Saccharomyces cerevisiae K35 were investigated in various concentrations of acetic acid, furfural, 5-hydroxymethylfurfural (5-HMF), syringaldehyde,
and coumaric acid. Fermentation in hydrolysates from yellow poplar and waste wood was also studied. After 24 h, S. cerevisiae K35 produced close to theoretically predicted ethanol yields in all the concentrations of acetic acid tested (1 ∼ 10 g/L).
Both furans and phenolics inhibited cell growth and ethanol production. Ethanol yield, however, was unaffected, even at high
concentrations, except in the cases of 5 g/L of syringaldehyde and coumaric acid. Although hydrolysates contain various toxic
compounds, in their presence, S. Cerevisiae K35 consumed close to all the available glucose and yielded more ethanol than theoretically predicted. S. Cerevisiae K35 was demonstrated to have high tolerance to inhibitory compounds and not to need any detoxification for ethanol production
from hydrolysates. 相似文献
964.
Cytoskeleton proteins are substrates for proteases and further apoptotic death. We evaluated the participation of cytoskeleton
in morphological changes during cell death induced by two apoptotic conditions, potassium deprivation (K5) and staurosporine,
in cerebellar granule neurons (CGC). We found that K5 induced somatic damage, but neurites were relatively preserved, which
corresponded to the reorganization of actin and α-tubulin in neurites. Staurosporine (STS) induced an early alteration of
neurites with reorganization of cytoskeleton proteins in somas. Caspase inhibitor ZVAD totally inhibited STS-induced α-tubulin
reorganization and partially blocked STS-induced actin reorganization. α-tubulin and actin reorganization induced by K5 was
affected by ZVAD. Calpain inhibitor (IC1) did not affect α-tubulin or actin reorganization induced by STS, K5 or ionomycin.
Neither ZVAD, nor IC1 changed α-tubulin or actin levels upon K5 treatment. STS increased α-tubulin and actin levels, but neither
ZVAD nor IC1 changed α-tubulin levels upon STS treatment. In contrast, ZVAD reduced the STS-induced increase of actin. These
results suggest that CGC cytoskeleton proteins undergo a differential expression and reorganization depending on the apoptotic
condition. 相似文献
965.
Fuel ethanol production from lignocellulosic materials is at a level where commercial biofuel production is becoming a reality. The solubilization of the hemicellulose fraction in lignocellulosic-based feedstocks results in a large variety of sugar mixtures including xylose. However, allowing xylose fermentation in yeast that normally is used for fuel ethanol production requires genetic engineering. Moreover, the efficiency of lignocellulosic pretreatment, together with the release and generation of inhibitory compounds in this step, are some of the new challenges faced during second generation ethanol production. Successful advances in all these aspects will improve ethanol yield, productivity and titer, which will reduce the impact on capital and operating costs, leading to the consolidation of the fermentation of lignocellulosic biomass as an economically feasible option for the production of renewable fuels. Therefore the development of yeast strains capable of fermenting a wide variety of sugars in a highly inhibitory environment, while maintaining a high ethanol yield and production rate, is required. This review provides an overview of the current status in the use of xylose-engineered yeast strains and describes the remaining challenges to achieve an efficient deployment of lignocellulosic-based ethanol production. 相似文献
966.
Jie Dai Jun Zhou Hongmei Liu Kaixun Huang 《Journal of biological inorganic chemistry》2016,21(8):1037-1046
Selenite and ebselen supplementation has been shown to possess anti-cataract potential in some experimental animal models of cataract, however, the underlying mechanisms remain unclear. The present study was designed to evaluate the anti-cataract effects and the underlying mechanisms of selenite and ebselen supplementation on galactose induced cataract in rats, a common animal model of sugar cataract. Transmission electron microscopy images of lens fiber cells (LFC) and lens epithelial cells (LEC) were observed in d-galactose-induced experimental cataractous rats treated with or without selenite and ebselen, also redox homeostasis and expression of proteins such as selenoprotein R (SELR), 15kD selenoprotein (SEP15), superoxide dismutase 1 (SOD1), catalase (CAT), β-crystallin protein, aldose reductase (AR) and glucose-regulated protein 78 (GRP78) were estimated in the lenses. The results showed that d-galactose injection injured rat lens and resulted in cataract formation; however, selenite and ebselen supplementation markedly alleviated ultrastructural injury of LFC and LEC. Moreover, selenite and ebselen supplementation could mitigate the oxidative damage in rat lens and increase the protein expressions of SELR, SEP15, SOD1, CAT and β-crystallin, as well as decrease the protein expressions of AR and GRP78. Taken together, these findings for the first time reveal the anti-cataract potential of selenite and ebselen in galactosemic cataract, and provide important new insights into the anti-cataract mechanisms of selenite and ebselen in sugar cataract. 相似文献
967.
Sedimentary Factors are Key Predictors of Carbon Storage in SE Australian Saltmarshes 总被引:1,自引:0,他引:1
Although coastal vegetated ecosystems are widely recognised as important sites of long-term carbon (C) storage, substantial spatial variability exists in quantifications of these ‘blue C’ stocks. To better understand the factors behind this variability we investigate the relative importance of geomorphic and vegetation attributes to variability in the belowground C stocks of saltmarshes in New South Wales (NSW), southeast Australia. Based on the analysis of over 140 sediment cores, we report mean C stocks in the surface metre of sediments (mean ± SE = 164.45 ± 8.74 Mg C ha?1) comparable to global datasets. Depth-integrated stocks (0–100 cm) were more than two times higher in fluvial (226.09 ± 12.37 Mg C ha?1) relative to marine (104.54 ± 7.11) geomorphic sites, but did not vary overall between rush and non-rush vegetation structures. More specifically, sediment grain size was a key predictor of C density, which we attribute to the enhanced C preservation capacity of fine sediments and/or the input of stable allochthonous C to predominantly fine-grained, fluvial sites. Although C density decreased significantly with sediment depth in both geomorphic settings, the importance of deep C varied substantially between study sites. Despite modest spatial coverage, NSW saltmarshes currently hold approximately 1.2 million tonnes of C in the surface metre of sediment, although more C may have been returned to the atmosphere through habitat loss over the past approximately 200 years. Our findings highlight the suitability of using sedimentary classification to predict blue C hotspots for targeted conservation and management activities to reverse this trend. 相似文献
968.
Rodolfo Jaffé Antonio Castilla Nathaniel Pope Vera Lucia Imperatriz-Fonseca Jean Paul Metzger Maria Cristina Arias Shalene Jha 《Conservation Genetics》2016,17(2):267-278
Pollination services are increasingly threatened by the loss and modification of natural habitats, posing a risk to the maintenance of both native plant biodiversity and agricultural production. In order to safeguard pollination services, it is essential to examine the impacts of habitat degradation on the population dynamics of key pollinators and identify potential “rescue pollinators” capable of persisting in these human-altered landscapes. Using a landscape genetic approach, we assessed the impact of landscape structure on genetic differentiation in the widely-distributed tropical stingless bee Trigona spinipes (Apidae: Meliponini) across agricultural landscape mosaics composed of coffee plantations and Atlantic forest fragments in southeastern Brazil. We genotyped 115 bees at 16 specific and highly polymorphic microsatellite loci, developed using next-generation sequencing. Our results reveal that T. spinipes is capable of dispersing across remarkably long distances, as we did not find genetic differentiation across a 200 km range, nor fine-scale spatial genetic structure. Furthermore, gene flow was not affected by forest cover, land cover, or elevation, indicating that reproductive individuals are able to disperse well through agricultural landscapes and across altitudinal gradients. We also found evidence of a recent population expansion, suggesting that this opportunistic stingless bee is capable of colonizing degraded habitats. Our results thus suggest that T. spinipes can persist in heavily-altered landscapes and can be regarded as a rescue pollinator, potentially compensating for the decline of other native pollinators in degraded tropical landscapes. 相似文献
969.
Marjana Regvar Urška Bukovnik Matevž Likar Ivan Kreft 《Central European Journal of Biology》2012,7(2):275-283
In the present study, we have evaluated the effects of increased UV-B radiation that simulates 17% ozone depletion, on fungal
colonisation and concentrations of rutin, catechin and quercetin in common buckwheat (Fagopyrum esculentum) and tartary buckwheat (Fagopyrum tataricum). Induced root growth and reduced shoot:root ratios were seen in both of these buckwheat species after enhanced UV-B radiation.
There was specific induction of shoot quercetin concentrations in UV-B-treated common buckwheat, whereas there were no specific
responses for flavonoid metabolism in tartary buckwheat. Root colonisation with arbuscular mycorrhizal fungi significantly
reduced catechin concentrations in common buckwheat roots, and induced rutin concentrations in tartary buckwheat, but did
not affect shoot concentrations of the measured phenolics. Specific UV-B-related reductions in the density of microsclerotia
were observed in tartary buckwheat, indicating a mechanism that potentially affects fungus-plant interactions. The data support
the hypothesis that responses to enhanced UV-B radiation can be influenced by the plant pre-adaptation properties and related
changes in flavonoid metabolism. 相似文献
970.
Lee CH 《Applied microbiology and biotechnology》2012,93(2):517-523
One of the primary limitations of cancer therapy is lack of selectivity of therapeutic agents to tumor cells. Current efforts
are focused on discovering and developing anticancer agents that selectively target only tumor cells and spare normal cells
to improve the therapeutic index. The use of preferentially replicating bacteria as an oncolytic agent is one of the innovative
approaches for the treatment of cancer. This is based on the observation that some obligate or facultative anaerobic bacteria
are capable of multiplying selectively in tumors and inhibiting their growth. Meanwhile, bacteria have been demonstrated to
colonize and destroy tumor, and have emerged as biological gene vectors to tumor microenvironment. To improve the efficacy
and safety of the bacterial therapy, a further understanding of bacteria between with immune system is required. Furthermore,
we want to evaluate how bacterial infection facilitates the “bystander effect” of chemotherapeutic agent and assess if it
can be used for additional antitumor effect when combined with chemotherapy. This study may not only evaluate therapeutic
efficacy of bacteria for the treatment of cancer but also elucidate the mechanisms underlying antitumor activities mediated
by bacteria, which involve host immune responses and the cellular molecular responses. 相似文献