浙江沿海地区海产品及环境中副溶血弧菌的分离与主要毒力基因分析

Analysis of Major Virulence Genes in Vibrio Parahaemolyticus Isolates from Coastal Areas in Zhejiang Province

摘要:

2007~2008年间, 我们调查了浙江沿海地区海产品和养殖环境中副溶血弧菌的污染状况, 并分析了不同来源副溶血弧菌中主要毒力相关基因tdh、trh、ureC和T3SS2(vscC2、vcrD2)的分布特征及溶血表型与尿素酶表型。结果显示, 566份样品中共分离到395株副溶血弧菌, 检出率高达70%, 毒力相关基因分析结果发现, tdh基因阳性率为10.1%, trh与ureC基因阳性率分别为 20.0%与 11.1%, 40株tdh+菌中组成T3SS2的vscC2基因阳性率为32.5%, 其中38株tdh+菌的神奈川试验亦呈阳性; 但在44株trh+-ureC+菌株中, 尿素酶表型阳性只有6株。试验表明, 浙江沿海地区海产品及其养殖环境中副溶血弧菌污染状况比较严重, 且有相当比例的菌株携带毒力或疑似毒力基因。研究结果为深入探索副溶血弧菌的致病性、基因结构与功能(或表型)及其分子演化提供基础。

Abstract:

Several aquatic species and their enviroments were examined for presence of Vibrio parahaemolyticus between 2007 and 2008 in the coastal areas in Zhejiang province, and some virulence-related genes such as tdh, trh, ureC and vscC2 were investigated from the isolates. V. parahaemolyticus was recovered from 70% of the samples tested (395/566). The genes tdh, trh and ureC existed in 10.1%, 20.0% and 11.1% respectively from 395 isolates. Among the 40 tdh-positive isolates, 32.5% harbored the vscC2 gene, one of the type three secretion system 2 (T3SS2) gene family. Thirty-eight of the 40 tdh-positive isolates were positive for the Kanagawa phenomenon. Out of 44 trh-and-ureC-positive isolates, only six exhibited urease phenotype. Overall, this study reveals the significant prevalence of Vibrio parahaemolyticus in seafoods and their habitats with high diversity of virulence genes. Representative V. parahaemolyticus isolates could be used for further investigation into their pathongenecity, functional genomics, and molecular evolution.