哈维氏弧菌VIB645毒性相关质粒的结构解析  

Random Sequencing and Sequence Analysis of the Virulence-Related Plasmid pVH1 from Vibrio harveyi VIB645

作　　者：侯晓阳[1] 孙铂光[1] 刘吉文[1] 孙婧[1] 张晓华[1] 

机构地区：[1]中国海洋大学海洋生命学院,山东青岛266003

出　　处：《中国海洋大学学报（自然科学版）》2011年第9期48-52,共5页Periodical of Ocean University of China

基　　金：教育部科学技术研究重点项目(108082);国家自然科学基金项目(30771656)资助

摘　　要：哈维氏弧菌(Vibrio harveyi)是水产养殖动物的常见致病菌。前期研究发现,哈维氏弧菌致病性最强的菌株VIB645含有2个核苷酸序列非常相似的溶血素基因—vhhA和vhhB,分别位于染色体DNA和1个大小约为65.6 kb的质粒上(命名为pVH1)。本研究用碱裂解法提取该菌株的毒性相关质粒pVH1,利用多种限制性内切酶进行酶切,构建随机DNA文库并测序。合计测序97.63 kb,覆盖度为148.3%,鉴定出125个ORF(开放阅读框,>150 bp)。这些预测的ORF,根据其功能主要分为以下几类:(1)毒力相关基因,包括RTX毒素钙离子结合蛋白、转铁蛋白结合蛋白A前体、外膜粘附蛋白;(2)结合转运相关基因,包括TraC、-D-、F-、G-、H-、I-、K-、N-、U-、W、TrbB-、C;(3)转座相关基因;(4)其他功能基因,如甲基转移酶,DNA结合蛋白,DNA复制蛋白DnaC等;(5)未知基因。本研究结果对揭示哈维氏弧菌的致病机理具有重要意义。Vibrio harveyi has emerged as a serious pathogen of aquaculture. Previous studies revealed that the most pathogenic isolate, VIB 645, contained two closely related hemolysin genes （designated vhhA and vhhB）. These two genes proved to be located in the genome and a plasmid （named pVH1） which is 65.6 kb in size. In this study, alkaline lysis method was used to extract the virulence-related plasmid pVH1 from Vibrio harveyi VIB645. The plasmid was digested by several restriction enzymes and sequenced by constructing random DNA library using pUC19c as vector. The total sequence fragments were 97.63 kb in size accounting for 148. 3% of the calculated length of pVH1 and 125 ORFs （〉150 bp） was identified. These ORFs could be grouped into 5 categories. （1） virulence-related genes, including genes encoding RTX toxins and related Ca2＋-binding protein, transferrin-binding protein A precursor, and outer membrane adhesion protein; （2） conjugal transfer related genes, including TraC, --D, -- F, -- G,--H,--I,--K,--N,--U,--W,TrbB,--C; （3） transposition related genes; （4） genes with other func- tions, including methyltransferase, DNA-binding protein RDGA, DNA replication protein DnaC and so on; （5） genes with unknown functions. These results are of great importance to reveal the pathogenicity mechanism of Vibrio harveyi.

关 键 词：哈维氏弧菌 毒性相关质粒 结构解析 

分 类 号：Q933[生物学—微生物学]