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981.
Jeong-Im Woo Sung-Hee Kil Huiqi Pan Yoo Jin Lee David J. Lim Sung K. Moon 《Biochemical and biophysical research communications》2014
Among the antimicrobial molecules produced by epithelial cells, DEFB4 is inducible in response to proinflammatory signals such as cytokines and bacterial molecules. Nontypeable Haemophilus influenzae (NTHi) is an important human pathogen that exacerbates chronic obstructive pulmonary disease in adult and causes otitis media and sinusitis in children. Previously, we have demonstrated that DEFB4 effectively kills NTHi and is induced by NTHi via TLR2 signaling. The 5′-flanking region of DEFB4 contains several NF-κB binding motifs, but their NTHi-specific activity remains unclear. In this study, we aimed to elucidate molecular mechanism involved in DEFB4 regulation, focusing on the role of the distal NF-κB binding motif of DEFB4 responding to NTHi. Here, we show that the human middle ear epithelial cells up-regulate DEFB4 expression in response to NTHi via NF-κB activation mediated by IκKα/β−IκBα signaling. Deletion of the distal NF-κB binding motif led to a significant reduction in NTHi-induced DEFB4 up-regulation. A heterologous construct containing the distal NF-κB binding motif was found to increase the promoter activity in response to NTHi, indicating a NTHi-responding enhancer activity of the distal NF-κB binding motif. Furthermore, electrophoretic mobility shift assays and chromatin immunoprecipitation assays showed that the p65 domain of NF-κB binds to the distal NF-κB binding motif in response to NTHi. Taken together, our results suggest that NTHi-induced binding of p65 NF-κB to the distal NF-κB binding motif of DEFB4 enhances NTHi-induced DEFB4 regulation in epithelial cells. 相似文献
982.
Abigail Perez-Valdespino Yunfeng Li Barbara Setlow Sonali Ghosh David Pan George Korza Florence E. Feeherry Christopher J. Doona Yong-Qing Li Bing Hao Peter Setlow 《Journal of bacteriology》2014,196(11):2077-2088
The Bacillus subtilis
spoVAEa and spoVAF genes are expressed in developing spores as members of the spoVA operon, which encodes proteins essential for the uptake and release of dipicolinic acid (DPA) during spore formation and germination. SpoVAF is likely an integral inner spore membrane protein and exhibits sequence identity to A subunits of the spore''s nutrient germinant receptors (GRs), while SpoVAEa is a soluble protein with no obvious signals to allow its passage across a membrane. However, like SpoVAD, SpoVAEa is present on the outer surface of the spore''s inner membrane, as SpoVAEa was accessible to an external biotinylation agent in spores and SpoVAEa disappeared in parallel with SpoVAD during proteinase K treatment of germinated spores. SpoVAEa and SpoVAD were also distributed similarly in fractions of disrupted dormant spores. Unlike spoVAD, spoVAEa is absent from the genomes of some spore-forming members of the Bacillales and Clostridiales orders, although SpoVAEa''s amino acid sequence is conserved in species containing spoVAEa. B. subtilis strains lacking SpoVAF or SpoVAEa and SpoVAF sporulated normally, and the spores had normal DPA levels. Spores lacking SpoVAF or SpoVAEa and SpoVAF also germinated normally with non-GR-dependent germinants but more slowly than wild-type spores with GR-dependent germinants, and this germination defect was complemented by ectopic expression of the missing proteins. 相似文献
983.
984.
Xin Ju Hui-Lei Yu Jiang Pan Dong-Zhi Wei Jian-He Xu 《Applied microbiology and biotechnology》2010,86(1):83-91
Substrate-directed screening was carried out to find bacteria that could deacylate O-acetylated mandelic acid from environmental samples. From more than 200 soil isolates, we identified for the first time that
Pseudomonas sp. ECU1011 biocatalytically deacylated (S)-α-acetoxyphenylacetic acid with high enantioselectivity (E > 200), yielding (S)-mandelic acid with 98.1% enantiomeric excess (ee) at a 45.5% conversion rate. The catalytic deacylation of (S)-α-acetoxyphenylacetic acid by the resting cell was optimized using a single-factor method to yield temperature and pH optima
of 30°C and 6.5, respectively. These optima help to reduce the nonselective spontaneous hydrolysis of the racemic substrate.
It was found that substrate concentrations up to 60 mM could be used. 2-Propanol was used as a moderate cosolvent to help
the substrate disperse in the aqueous phase. Under optimized reaction conditions, the ee of the residual (R)-α-acetoxyphenylacetic acid could be improved further, to greater than 99%, at a 60% conversion rate. Furthermore, using
this newly isolated strain of Pseudomonas sp. ECU1011, three kinds of optically pure analogs of (S)-mandelic acid and (R)-α-acetoxyphenylacetic acid were successfully prepared at high enantiomeric purity. 相似文献
985.
Tao Pan Zhilong Wang Jian-He Xu Zhenqiang Wu Hanshi Qi 《Applied microbiology and biotechnology》2010,85(6):1789-1796
Extractive microbial fermentation for production of lipase by Serratia marcescens ECU1010 has been carried out in cloud point system. The cloud point system is composed of mixture nonionic surfactants with
a ratio of Triton X-114 to Triton X-45 4:1 in aqueous solution. The lipase prefers to partition into the surfactant rich phase
(coacervate phase) whereas the cells and other hydrophilic proteins retain in the dilute phase of cloud point system. Thus,
a concentration factor 4.2-fold and a purification factor 1.3-fold of the lipase have been achieved in the extractive fermentation
process. This is the first report about extractive fermentation of proteins in cloud point system. 相似文献
986.
J. Y. Zhu Xuejun Pan Ronald S. Zalesny Jr. 《Applied microbiology and biotechnology》2010,87(3):847-857
This mini review discusses several key technical issues associated with cellulosic ethanol production from woody biomass:
energy consumption for woody biomass pretreatment, pretreatment energy efficiency, woody biomass pretreatment technologies,
and quantification of woody biomass recalcitrance. Both total sugar yield and pretreatment energy efficiency, defined as the
total sugar recovery divided by total energy consumption for pretreatment, should be used to evaluate the performance of a
pretreatment process. A post-chemical pretreatment wood size-reduction approach was proposed to significantly reduce energy
consumption. The review also emphasizes using a low liquid-to-wood ratio (L/W) to reduce thermal energy consumption for any
thermochemical/physical pretreatment in addition to reducing pretreatment temperature. 相似文献
987.
Rong Pan Lixiang Cao Haiwei Huang Renduo Zhang Yu Mo 《Applied microbiology and biotechnology》2010,88(4):997-1005
In this study, dried and humid fruiting bodies of Tremella fuciformis and Auricularia polytricha were examined as cost-effective biosorbents in treatment of heavy metals (Cd2+, Cu2+, Pb2+, and Zn2+) in aqueous solution. The humid T. fuciformis showed the highest capacity to adsorb the four metals in the multi-metal solutions. The Pb2+ adsorption rates were 85.5%, 97.8%, 84.8%, and 91.0% by dried T. fuciformis, humid T. fuciformis, dried A. polytricha, and humid A. polytricha, respectively. The adsorption amount of Pb2+ by dried and humid T. fuciformis in Cd2+ + Pb2+, Cu2+ + Pb2+, Pb2+ + Zn2+, Cd2+ + Cu2+ + Pb2+, and Cd2+ + Zn2+ + Pb2+ solutions were not lower than that in Pb2+ solutions. The results suggested that in humid T. fuciformis, Cd2+, Cu2+, and Zn2+ promoted the Pb2+ adsorption by the biomass. In the multi-metal solutions of Cd2+ + Cu2+ + Pb2+ + Zn2+, the adsorption amount and rates of the metals by all the test biosorbents were in the order of Pb2+ > Cu2+ > Zn2+ > Cd2+. Compared with the pseudo first-order model, the pseudo second-order model described the adsorption kinetics much better,
indicating a two-step biosorption process. The present study confirmed that fruiting bodies of the jelly fungi should be useful
for the treatment of wastewater containing Cd2+, Cu2+, Pb2+, and Zn2+. 相似文献
988.
Yan Shan Chunting Wang Li Yang Li Juan Chen Hong Xin Deng Han Shuo Yang Zhimian Li Zhiyong Li Li Pan Fei Leng Yuquan Wei 《Journal of biosciences》2010,35(2):209-216
Anti-apoptosis plays an important role in tumour formation and development. Survivin is a member of the inhibitor of apoptosis (IAP) family, which is a target for anti-cancer drug exploitation was replaced as development. We investigated the role of the homo dominant-negative mutant Survivin-T34A in suppressing human lung adenocarcinomas (A549). The anti-tumour activity of HSurvivinT34A plasmid was evaluated in the A549 cell line and nude mice bearing A549 subcutaneous tumours. Low-dose systemic administration was continuously used. The HSurvivinT34A plasmid (5 µg/one) complexed with a cationic liposome (DOTAP/Chol) significantly inhibited tumour growth in our model. We observed microvessel density degradation by CD31 immunohistochemistry and apoptotic cell increase by TUNEL assay, PI staining and flow cytometric analysis in the treated group. The present findings suggest that the HSurvivinT34A plasmid complexed with a cationic liposome may provide an effective approach to inhibit the growth of human lung adenocarcinomas in vitro and in vivo. 相似文献
989.
2006—2008年夏季(7—8月),对甘肃兴隆山自然保护区马麝(Moschus Sifanicus)的栖息地特征和夏季生境选择格局进行了研究。用Mann-Whitney U检验和χ2检验比较了马麝夏季利用生境样地(n=71)和对照性非利用样地(n=264)间的海拔等17个生态变量的差异,结果表明,兴隆山马麝夏季利用生境的郁闭度[(53.87±3.09)%]和乔木均高[(7.57±0.83)m]均显著大于非利用样地[郁闭度:(49.07±1.66)%,乔木均高:(6.33±0.32)m],喜食植物多度[(12.97±1.80)]株也显著大于非利用样地[(9.61±0.67)株]。此外,与非利用样地相比,兴隆山马麝夏季倾向于选择位于中坡位较陡(67.61%)、距离水源较近(<1000m,77.46%)、隐蔽度(88.73%)和避风性均较好(90%)及距人为干扰较远(>1000m,76.06%)的生境;主成分分析结果表明,前4个因子的累积贡献率达72.45%,由乔木胸径和乔木郁闭度变量组成的乔木因子是决定马麝夏季生境选择的首要因素,此外,海拔因子,由地表植被盖度和食物多度组成的食物因子,由灌木盖度、乔木密度和灌木... 相似文献
990.
Qing-Qiu Mao Xiao-Ming Zhong Chun-Rong Feng Ai-Juan Pan Zhao-Yi Li Zhen Huang 《Cellular and molecular neurobiology》2010,30(7):1059-1066
Preclinical and clinical investigations have shown hippocampal neuronal atrophy and destruction were observed in patients
with depression, which could be ameliorated by the treatment with antidepressants. Therefore, neuroprotection has been proposed
to be one of the acting mechanisms of antidepressant. Paeoniflorin, a monoterpene glycoside, has been reported to display
antidepressant-like effects in animal models of behavioral despair. The present study aimed to examine the protective effect
of paeoniflorin on glutamate-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. The results showed that
pretreatment with paeoniflorin elevated cell viability, inhibited apoptosis, decreased levels of intracellular reactive oxygen
species and malondialdehyde, and enhanced activity of superoxide dismutase in glutamate-treated PC12 cells. Pretreatment with
paeoniflorin also reversed the increased intracellular Ca2+ concentration and the reduced Calbindin-D28K mRNA level caused by glutamate in PC12 cells. The results suggest that paeoniflorin
exerts a neuroprotective effect on glutamate-induced neurotoxicity in PC12 cells, at least in part, via inhibiting oxidative
stress and Ca2+ overload. This neuroprotective effect may be one of the action pathways accounting for the in vivo antidepressant activity
of paeoniflorin. 相似文献