CTXΦ在霍乱弧菌两个染色体上的整合分析  

Integration analysis of CTXΦin two chromosomes of Vibrio cholerae

作　　者：田德桥[1] 闫梅英[1] 高守一[1] 阚飙[1] 

机构地区：[1]中国疾病预防控制中心传染病预防控制所

出　　处：《中华微生物学和免疫学杂志》2006年第8期729-733,共5页Chinese Journal of Microbiology and Immunology

基　　金：国家重大基础研究发展规划(973)项目(G1999054102)

摘　　要：目的研究CTXΦ是否可以在没有TLC(toxin-linked cryptic)因子的非产毒霍乱弧菌染色体上整合,以及是否可以在霍乱弧菌小染色体上整合。方法筛选染色体上没有整合CTXΦ及TLC基因组的霍乱菌株(CTX-TLC-),检测这类菌株染色体上是否有类似的CTXΦ染色体整合位点attB。以含有CTXΦ的RS区及整合位点的自杀质粒pKRSn与pKRSe结合转移到CTX-TLC-及CTX- TLC+菌株,观察染色体整合情况,并分析整合位置的序列。结果CTX-TLC-菌株存在与CTXΦ染色体整合位点相似的序列。在CTX+TLC-菌株当中,CTXΦ基因组存在于小染色体上。自杀质粒pKRSn与pKRSe可以在TLC+及TLC-菌株的大染色体发生整合,也可以在TLC-菌株的小染色体发生整合。结论CTXΦ可以在霍乱弧菌的两条染色体上通过高度相似或一致的attB位点发生整合,另外也提示TLC在CTXΦ的大染色体整合中可能发挥作用。Objective To investigate whether CTXΦ can integrate into the chromosome of the TLC negative and non-toxigenic Vibrio cholerae strains, and whether it can integrate into V. cholerae chromosome Ⅱ . Methods The corresponding chromosomal fi＇agments of the CIX^- TLC^- strains were sequenced to detect the presence of the reported CTXΦ chromosome integrate site attB. The recombinant suicide plasmid pKRSn and pKRSe which carrying RS region and attP of CTXΦ were transformed into CTX^- TLC^- and CTX^- TLC^＋ strains, to analyze the chromosome integration and their integration sites. Results CTX^- TLC^- strains have a short sequence similar with attP of CTXΦ. In CTX^- TLC^- strains, CTXΦ integrates into chromosome Ⅱ . pKRSn and pKRSe can integrate into chromosome Ⅰ in TLC^＋ and TLC^- strain, in TLC^- strain they are found to integrate into chromosome Ⅱ . Conclusion CTXΦ can integrate into chromosomes of V. cholerae through the similar integrate sites. It also suggests that TLC may play a role in the chromosome Ⅰ integration of CTXΦ.

关 键 词：霍乱弧菌 CTXΦ 整合 

分 类 号：R378[医药卫生—病原生物学]