多位点序列分型技术在深圳副溶血弧菌同源性分析中的应用研究

目的 了解副溶血弧菌临床分离株的毒力基因、血清型及基因分型特征,探讨多位点序列分型(MLST)分型技术对其同源性分析的应用价值。方法 收集深圳地区2007-2014年食物中毒及医院散发病例来源的68株副溶血弧菌菌株,对其进行血清型、毒力基因分析。选择副溶血弧菌MLST数据库提供的7个管家基因,PCR扩增测序后采用BioEdit、eBURST等软件,对本次研究的68株副溶血弧菌进行MLST同源性分析。结果 68株副溶血弧菌共得到7种不同的血清型,优势血清型为O3∶K6(47/68),其余血清型分别为O4∶K8、O5∶K68、O4∶K13等。副溶血弧菌临床分离株94%为tdh+trh-。MIST分型将68株副溶血弧菌分为5个序列型(ST型),ST3为优势序列型(55/68),其余4种ST型中的ST189与ST345构成一个同源复合体CC345,且ST189为ST345的单位点变异型。结论 深圳地区副溶血弧菌所致的腹泻病暴发疫情,其流行菌株ST型别多样化,疾病控制中需警惕非主流ST型别引起暴发可能。

Multilocus sequence typing technique in homology analysis of Vibrio parahaemolyticus,Shenzhen

Objective To probe the virulence gene,serotype and genotyping characteristics of clinical isolated Vibrio parahaemolyticus,and to discuss the application value of multilocus sequence typing technique (MLST) in the homology analysis. Methods We collected 68 strains of Vibrio parahaemolyticus from food poisoning and hospital sporadic cases in Shenzhen District from 2007 to 2014,and analyzed their serotypes and virulence genes. 7 housekeeping genes provided by V. parahaemolyticus MLST database were amplified and sequenced in the way of PCR. Then,the homology on 68 strains of V. parahaemolyticus was analyzed by using MLST with BioEdit and eBURST software. Results 7 kinds of serotypes were obtained from the 68 strains of V. parahaemolyticus. The superiority serotype was O3∶K6 (47/68). The rest were O4∶K8,O5∶K68,O4∶K13 and so on. 94% of clinical isolated V. parahaemolyticus were tdh+trh-. The 68 V. parahaemolyticus strains were divided into 5 kinds of different ST types by MLST. The superiority type was ST3 (55/68). In the rest 4 ST types,ST189 and ST345 constituted a homologous complex CC345. Besides,ST189 was a unit variant of ST345. Conclusion The ST types of popular strains on V. parahaemolyticus are various,which come from the outbreak of diarrheal disease in Shenzhen. We need to be vigilant against non-mainstream ST types which may be likely to cause outbreaks.