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961.
Zhiyuan Yao Gang Wei Haizhen Wang Laosheng Wu Jianjun Wu Jianming Xu 《Applied and environmental microbiology》2013,79(5):1755-1756
Escherichia coli O157:H7 survived longer in soils from plastic-greenhouse cultivation than soils from the open field. Soil pH, organic carbon levels, and the ratio of bacterial phospholipid fatty acids (PLFAs) to fungal PLFAs played the significant roles in survival of O157:H7. Greater attention should be paid to the control of pathogen contamination under conditions of plastic-greenhouse cultivation. 相似文献
962.
Meng Liu Hongyan Liu Xiaocui Guan Hongxin Ai Haitao Wu Ping Liu Wei Gu Shuangquan Zhang 《Immunogenetics》2013,65(12):873-882
The interferon-γ-inducible lysosomal thiol reductase (GILT) has been demonstrated to play an important role in the processing and presentation of MHC class II-restricted antigen (Ag) by catalyzing disulfide bond reduction. In this study, a rainbow trout cDNA (designated as rGILT) was cloned and identified from Oncorhynchus mykiss. The open reading frame of rGILT consists of 759 bases encoding a protein of 253 amino acids with an estimated molecular mass of 28.23 kDa and a theoretical isoelectric point of 4.94. The rGILT exhibited a characteristic GILT signature sequence CQHGX2ECX2NX4C and CXXC motif. Phylogenetic analysis suggested that rGILT had been derived from a common ancestor with other GILT proteins. RT-PCR results showed that rGILT and rIFN-γ (rainbow trout IFN-γ) mRNA was expressed in a tissue-specific manner and obviously up-regulated in splenocytes and the cells from head kidney after induction with LPS. Recombinant rGILT fused with His6 tag was efficiently expressed in Escherichia coli BL21 (DE3) and purified by Ni-NTA affinity chromatography. Further study revealed that rGILT was capable of catalyzing the reduction of the interchain disulfide bonds from intact IgG. This study shows that rGILT may be involved in the immune response to bacteria challenge and maintain first line of innate immune defense at basal level in O. mykiss. It also provides the basis for investigating on the role of GILT using O. mykiss as an animal model for related studies. 相似文献
963.
Haifeng Lu Jianqing He Zhongwen Wu Wei Xu Hua Zhang Ping Ye Jiezuan Yang Shusen Zhen Lanjuan Li 《Microbial ecology》2013,65(3):781-791
Understanding the composition of the microbial populations in the intestines of liver transplant patients is important to preventing postoperative infection. We investigated the relationship between the risk of postoperative infection and variation in the predominant fecal microbial composition during the perioperative period. We prospectively analyzed the predominant intestinal microbiome of five asymptomatic adult carriers of hepatitis B virus (as controls without any antibiotics) at four weekly follow-up visits and 12 patients before operation and at three weekly postoperative follow-up visits within the first month. Analysis was by denaturing gradient gel electrophoresis (DGGE) and sequencing with digital processing of DGGE profiles using BioNumerics software. Our results showed that the predominant intestinal microbial diversity decreased substantially in eight patients during the perioperative period. Among these, five patients experienced infection with a postoperative hospital stay of more than 30 days. The rest of the four patients who experienced shorter postoperative hospital stays showed only slight variation in predominant intestinal bacterial composition and temporal stability similar to asymptomatic controls. Postoperative fecal DGGE profiles showed mostly bands assigned to Bacteroides and Firmicutes. We conclude that an empiric prophylaxis strategy that destructs gut microecological balance will not be effective in reducing the risk of postoperative infection. Instead, the destruction of intestinal microbiota might result in the appearance of opportunistic pathogens such as Bifidobacterium dentium which rarely appears in the intestinal DGGE profiles of normal humans. Cognizance of the variation of intestinal microbial profiles during the perioperative period is a critical aspect of caring for liver transplant recipients. 相似文献
964.
G. D. Chen Y. X. Liu Y. M. Wei C. L. McIntyre M. X. Zhou Y.-L. Zheng C. J. Liu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(10):2511-2520
Fusarium crown rot (FCR) is a serious cereal disease in semi-arid regions worldwide. In assisting the effort of breeding cultivars with enhanced resistance, we identified several barley genotypes with high levels of FCR resistance. One of these genotypes, AWCS079 which is a barley landrace originating from Japan, was investigated by developing and assessing three populations of recombinant inbred lines. Two QTL, one located on the long arm of chromosome 1H (designated as Qcrs.cpi-1H) and the other on 3HL (designated as Qcrs.cpi-3H), were found to be responsible for the FCR resistance of this genotype. Qcrs.cpi-1H is novel as no other FCR loci have been reported on this chromosome arm. Qcrs.cpi-3H co-located with a reduced height (Rht) locus and the effectiveness of the former was significantly affected by the latter. The total phenotypic variance explained by these two QTL was over 60 %. Significant effects were detected for each of the QTL in each of the three populations assessed. The existence of these loci with major effects should not only facilitate breeding and exploitation of FCR-resistant barley cultivars but also their further characterization based on fine mapping and map-based gene cloning. 相似文献
965.
Wei Wang Xiaofeng Ji Cui Yuan Fangqun Dai Jiancheng Zhu Mi Sun 《Indian journal of microbiology》2013,53(4):477-481
Catalase plays an important role in the metabolism of marine bacteria and has potential impact on the marine environment. Four PCR primers were designed to amplify the catalase gene fragments in marine bacteria by applying metagenomic DNA from Yellow Sea surface water as the template. Of the four reproducible target PCR products, the longest one with 900 bp were chosen for catalase gene library construction by the T-vector and the white Escherichia coli colonies in the library was screened through restriction-digesting the reamplified insert fragments by the selected restriction endonuclease MboI, and then the bands of the resulting products were displayed in the agarose gel by electrophoresis. The unique restriction fragment length polymorphism (RFLP) pattern was selected and the corresponding catalase gene fragments were sequenced, which verified that every unique RFLP pattern represented one type of catalase. This PCR–RFLP method above was established to investigate the bacterial catalase diversity in seawater. 相似文献
966.
967.
Yunfeng Zha Jiexiong Xie Ye Chen Chunya Wei Wanjun Zhu Jidang Chen Haitao Qi Liangquan Zhang Long Sun Xiaozhan Zhang Pei Zhou Zhenpeng Cao Wenbao Qi Minze Zhang Zhen Huang Guihong Zhang 《Indian journal of microbiology》2013,53(4):496-498
The primary objective of this 3 years study was to determine the prevalence of porcine pathogens of the lungs of swine in swine farms in southern China. A total of 5,420 samples were collected from 200 swine farms. The bacterium that was most commonly isolated was Streptococcus suis, with 10.24 % of the samples being positive, 114 lungs (2.1 %) were positive for pseudorabies virus and 263 (4.85 %) were positive for classical swine fever virus; much lower than positive for PRRSV (15.1 %, p = 0.023) and PCV2 (13.8 %, p = 0.038). lungs that were positive for PRRSV and/or PCV-2 have significantly increased odds of being positive for any of the S. suis (9.79 vs. 0.44 %, p = 0.003). 相似文献
968.
969.
Hyun Seok Kim Saurabh Mendiratta Jiyeon Kim Chad Victor Pecot Jill E. Larsen Iryna Zubovych Bo Yeun Seo Jimi Kim Banu Eskiocak Hannah Chung Elizabeth McMillan Sherry Wu Jef De Brabander Kakajan Komurov Jason E. Toombs Shuguang Wei Michael Peyton Noelle Williams Adi F. Gazdar Bruce A. Posner Rolf A. Brekken Anil K. Sood Ralph J. Deberardinis Michael G. Roth John D. Minna Michael A. White 《Cell》2013