一株死亡患者分离的致死创伤弧菌菌株的耐药表型与分子特征

Drug resistance phenotype and molecular characteristics of a virulent Vibrio vulnificus strain isolated from a fatal case

目的对培养分离的创伤弧菌菌株(2014-DJH)进行耐药表型与分子特征分析。方法采用全自动微生物鉴定及药敏分析系统进行生化鉴定和耐药分析;采用PCR方法检测vvh A基因和pil F基因,及vcg和16S rRNA基因分型;应用多位点序列分析进行分子分型。结果分离菌株2014-DJH经生化鉴定为革兰阴性的生物1型创伤弧菌;对大多数常用抗生素都敏感,对妥布霉素中度敏感;PCR检测vvh A和pil F阳性,为vcg C-16S rRNA B(CB)基因型;菌株的多位点序列型为glp 5、gyr B 3、mdh 32、met G 68、pur M 21、dtd S 39、lys A 115、pnt A 4、pyr C 42、tna A 75。结论菌株2014-DJH为新ST型菌株,命名为ST 289,注册号为id-389。基因分型结果表明该菌具有较强的致病能力,加强创伤弧菌感染的监测与预警具有重要的意义。

Objective To study the drug resistance phenotype and molecular characteristics of a Vibrio vulnificus strain（ 2014-DJH） isolated from a fatal case. Methods The biochemical test and antibiotic susceptibility test of the isolate 2014-DJH were conducted using VITEK-2 COMPACT. PCR was performed to detect the vvh A gene,pil F gene and characterize the genotype of vcg and 16 S rRNA loci,and multilocus sequence typing（ MLST） was used for the molecular typing of the isolate. Results The isolate was identified as a gram-negative biotype 1 V. vulnificus strain,and it was sensitive to the most tested antibiotics,but intermediate to tobramycin. It was positive for the vvh A gene,pil F gene and identified as the vcg C-16 S rRNA B genotype（ CB）. The MLST allele numbers of 2014-DJH were glp 5,gyr B 3,mdh 32,met G 68,pur M21,dtd S 39,lys A 115,pnt A 4,pyr C 42 and tna A 75. Conclusion The isolate 2014-DJH was identified as a newtype ST strain,named ST289 with the number id-389. Its genotyping results showed that this type strain has strong pathogenicity,so it is important to strengthen the monitoring and early warning of V. vulnificus infection.