期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
生物催化硫醚底物的不对称氧化反应研究进展 被引量:1
1
作者 卓俊睿 陈永正 《合成化学》 CAS CSCD 2015年第5期456-460,共5页
综述了生物催化硫醚底物的不对称氧化反应的研究进展,重点介绍了微生物菌株整细胞、纯酶和基因工程菌等催化剂在硫醚底物的不对称氧化反应中的应用。参考文献32篇。
关键词 生物催化 硫醚 整细胞 基因过程菌 不对称氧化
下载PDF
Screening Helicobacter pylori genes induced during infection of mouse stomachs 被引量:5
2
作者 Aparna Singh Nathaniel Hodgson +9 位作者 Ming Yan Jungsoo Joo Lei Gu Hong Sang Emmalena Gregory-Bryson William G Wood Yisheng Ni Kimberly Smith Sharon H Jackson William G Coleman 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第32期4323-4334,共12页
AIM:To investigate the effect of in vivo environment on gene expression in Helicobacter pylori(H.pylori) as it relates to its survival in the host.METHODS:In vivo expression technology(IVET) systems are used to identi... AIM:To investigate the effect of in vivo environment on gene expression in Helicobacter pylori(H.pylori) as it relates to its survival in the host.METHODS:In vivo expression technology(IVET) systems are used to identify microbial virulence genes.We modified the IVET-transcriptional fusion vector,pIVET8,which uses antibiotic resistance as the basis for selection of candidate genes in host tissues to develop two unique IVET-promoter-screening vectors,pIVET11 and pIVET12.Our novel IVET systems were developed by the fusion of random Sau3A DNA fragments of H.pylori and a tandem-reporter system of chloramphenicol acetyltransferase and beta-galactosidase.Additionally,each vector contains a kanamycin resistance gene.We used a mouse macrophage cell line,RAW 264.7 and mice,as selective media to identify specific genes that H.pylori expresses in vivo.Gene expression studies were conducted by infecting RAW 264.7 cells with H.pylori.This was followed by real time polymerase chain reaction(PCR) analysis to determine the relative expression levels of in vivo induced genes.RESULTS:In this study,we have identified 31 in vivo induced(ivi) genes in the initial screens.These 31 genes belong to several functional gene families,including several well-known virulence factors that are expressed by the bacterium in infected mouse stomachs.Virulence factors,vacA and cagA,were found in this screen and are known to play important roles in H.pylori infection,colonization and pathogenesis.Their detection validates the efficacy of these screening systems.Some of the identified ivi genes have already been implicated to play an important role in the pathogenesis of H.pylori and other bacterial pathogens such as Escherichia coli and Vibrio cholerae.Transcription profiles of allivi genes were confirmed by real time PCR analysis of H.pylori RNA isolated from H.pylori infected RAW 264.7 macrophages.We compared the expression profile of H.pylori and RAW 264.7 coculture with that of H.pylori only.Some genes such as cag A,vac A,lpx C,mur I,tlp C,trx B,sod B,tnp B,pgi,rbf A and inf B showed a 2-20 fold upregulation.Statistically significant upregulation was obtained for all the above mentioned genes(P < 0.05).tlp C,cag A,vac A,sod B,rbf A,inf B,tnp B,lpx C and mur I were also significantly upregulated(P < 0.01).These data suggest a strong correlation between results obtained in vitro in the macrophage cell line and in the intact animal.CONCLUSION:The positive identification of these genes demonstrates that our IVET systems are powerful tools for studying H.pylori gene expression in the host environment. 展开更多
关键词 Helicobacter pylori In vivo expression technology Virulence genes Mice Infection
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部