气单胞属菌粪便分离株分子鉴定与耐药元件检测

目的 调查一组14株气单胞属菌的菌种分子鉴定情况,以及β-内酰胺酶类、氨基糖苷类耐药的遗传学背景。方法 14株气单胞属菌均分离自2012年1月至12月宁波市第一医院肠道门诊腹泻患者的粪便标本,再作通用引物16SrDNA测序比对判定菌种,然后用聚合酶链反应(PCR)的方法分析23种β-内酰胺酶基因、6种氨基糖苷类修饰酶基因和6种16SrRNA甲基化酶基因以及6种可移动遗传元件分子标记。结果 本组14株菌经16SrDNA测序比对,10株为嗜水气单胞菌, 水簇箱气单胞菌、温和气单胞菌、肠棕气单胞菌、斑点气单胞菌各1株。14株气单胞菌共检出5种β-内酰胺酶基因、4种氨基糖苷类修饰酶基因和3种可移动遗传元件遗传标记基因。其中4号株(嗜水气单胞菌)AQU基因是新的基因亚型,命名为AQU-2, 11号株(水簇箱气单胞菌)AQU基因也是新的基因亚型,命名为AQU-3。结论 气单胞菌属的菌种鉴定应该以分子鉴定法为准。本组14株气单胞属菌耐药严重,已呈多重耐药。

Molecular identification and resistant derterminants of Aeromonas sp. isolated from stool of human

We investigated molecular identification of a group of 14 strains of Aeromonas sp., and genetic background of resistance to beta-lactams, aminoglycosides. From January to December 2012, 14 strains of Aeromonas sp. were collected from stool from diarrheal patients in enteric clinics in Ningbo First Hospital in Zhejiang Province, China. Then, molecular identification by 16SrDNA, 23 kinds of beta-lactamase genes, 6 kinds of aminoglycoside modifying enzyme genes, 6 kinds of 16srRNA methylase genes, and 6 kinds of mobile genetic elements were analyzed by PCR. In addition, genotyping and sample cluster analysis were performed. Results showed that 10 strains of A. hydrophila, 1 strain of A. aquariorum, A. sobria, A. enteropelogenes, A. punctata were confirmed by 16SrDNA sequencing and arithmetic. Five kinds of beta-lactamase genes, 4 kinds of aminoglycoside modifying enzyme genes, and 3 kinds of mobile genetic elements were positive. BlaAQU of strain No.4(AQU-2) and strain No.11(AQU-3) were new subtypes. It’s suggested that identification of Aeromonas sp. should be performed by molecular identification method. This group of 14 strains of Aeromonas sp. conferred multidrug resistance.