摘要
本文以柯斯质粒pJB8作载体,经体外包装构建了志贺氏菌属弗氏5大质粒(140Md)基因文库,获得重组子4000多个。用已证实与侵袭力相关的17kb基因片段作探针,从基因文库中筛选出66个相应的重组子。对其中部分重组子进行分析,表明这些重组子均包含一个大的重组质粒,它们与17kb探针杂交呈阳性反应。当用EcoR 1酶解这些重组质粒时,均产生大小相当于17kb的DNA片段,它们与17 kb探针杂交,也呈阳性反应。表明这些重组子均含与侵袭相关的基因片段。这为以后构建预防痢疾的口服活菌苗打下了基础。
A genomic library of S.flexncri 5 large plasmid (140 Md) was constructed using the cosmid pJB8 as vector.There were more than 4,000 transformants in the library.66 clones were picked out from the library by hybridization with 17kb gene probe relative to invasive ability.A few clones were analyzed.The results indicated that all these clones tested contained recombinant plasmids,they could hybridize with 17 kb gene probe.When these recombinant plasmids were digested with EcoR1,17 kb fragments which hybridized with 17 kb gene probe always existed in these recombinant plasmids.It showed that all these recombinant plasmids contained the DNA fragments relative to invasive ability.It provides the possibility to construct-an oral living vaccine against S.flexneri.
关键词
克隆
志贺氏菌属
基因文库
重组子
Cosmid pJB8,S. flexneri 5,Genomic library,Recombinants
