沿海地区副溶血弧菌的表型及其主要毒力基因分布特征

Vibrio parahaemolyticus Strains from Zhejiang Coastal Areas: Phenomena and Distribution of Major Virulent Genes

为了调查浙江沿海地区副溶血弧菌的分布及其携带毒力基因的特征,在舟山、象山、温州三地实地采样385份,包括海水、泥土和水产品等,共分离到副溶血弧菌菌株278份,其中27株为tdh基因阳性,阳性率为9.7%,trh与ureC基因的阳性率分别为22.3%与11.8%,提示浙江沿海地区广泛存在着致病性副溶血弧菌污染。将不同来源副溶血弧菌的tdh和trh基因进行序列测定,进化树分析发现,环境分离株中tdh基因与临床分离株中tdh基因区分为2簇,而环境分离株与临床分离株中trh基因之间却没有明显的差异。研究结果可为浙江沿海地区副溶血弧菌的风险评估提供参考。

To investigate the distribution of virulence genes in V.parahaemolyticus isolates from the marine aquaculture system in the coastal cities in Zhejiang province,a total of 278 V.parahaemolyticus isolates were recovered from 385 samples of seawater,mud and seafoods in Zhoushan,Xianshan and Wenzhou city and then investigated for their hemolytic and urease producing phenotypes,presence of putative virulence genes tdh and trh genes.Twenty-seven isolates（9.7%）were tdh-positive while sixty-two isolates（22.3%）and thirty-three isolates（11.8%）were positive for trh and ureC genes,respectively,and the results showed that the contamination of pathogenic V.parahaemolyticus in Zhejiang coastal areas.The tdh and trh genes from the isolates which were detected positive by PCR were further cloned and sequenced,phylogenetic analysis indicated that all the tdh genes from seafood-related samples were clustered in the same group,while the tdh genes from clinical isolates fell into a separate group.There were no significant differences of the trh genes between seafood-related isolates and those from clinical source.The results gave the important reference for the V.parahaemolyticus risk assessment of Zhejiang province.