沈阳地区副溶血弧菌脉冲场凝胶电泳分析

目的 运用脉冲场凝胶电泳技术(pulsed-fieldgelelectro phoresis,PFGE)和PCR技术对辽宁沈阳市2010年7-8月份临床粪便标本分离的副溶血性弧菌进行毒力基因检测和分子分型分析.方法 运用PCR技术检测24株副溶血弧菌的耐热溶血素基因(tdh)、耐热溶血素相关溶血素基因(trh)和不耐热溶血素基因(tl);用PFGE技术对其进行分子分型和聚类分析.结果 24株副溶血弧菌均含有tdh和tl基因,表明均为有毒株;PFGE结果显示,24株菌株可分为10种图谱型,其中17株O3:K6被分为4种型别(仅相差1～3条带),表明17株O3:K6在流行病学上密切相关,提示沈阳地区可能存在副溶血弧菌腹泻病的局部暴发或流行.结论 沈阳地区流行的食源性副溶血弧菌存在基因型的多样性,但以遗传关系密切的O3:K6型为优势型别.

Molecular analysis of foodborne Vibrio parahaemolyticus strains isolated in Shenyang area by pulsed-field gel electrophoresis

Objective To detect the virulence genes of the Vibrio parahaemolyticus(V.parahaemolyticus) strains which were isolated from the stool specimens of patients in Shenyang city from July to August,2010,and to subtype the isolates by pulsed-field gel electrophoresis(PFGE) analysis. Methods The virulence genes,thermostable direct hemolysin(tdh),thermostable direct hemolysin-related hemolysin(trh),and thermolabile hemolysin(tl) were amplified by PCR technique.The isolates were subtyped by PFGE analysis and the PFGE banding patterns were analyzed. Results The 24 V.parahaemolyticus isolates contained tdh and tl genes.This results revealed that they were all virulent strains.Ten banding patterns were observed by PFGE analysis.Of the 24 isolates,17 strains of O3:K6 were typed into 4 genotypes,but they had only 1-3 band differences and thus they were regarded as closely related.The findings indicated that the epidemic or outbreak of V.parahaemolyticus may exist in Shenyang region. Conclusion The V.parahaemolyticus strains prevalent in the region showed serotype and genotype diversity,but the closely related O3:K6 was the pandemic serotype.The results provide technical and data support for the establishment of V.parahaemolyticus molecular typing database,the outbreak investigation and the source-tracking.