大肠埃希菌中16S rRNA甲基化酶armA基因的分布与耐药性的研究  

Research on the methylase gene arm A 16S rRNA distribution and drug resistance in Escherichia coli

作　　者：李国华[1] 刘琪[2] 黎敏华[3] 

机构地区：[1]绍兴市中医院,浙江绍兴312000 [2]绍兴市人民医院临床检验中心,浙江绍兴312000 [3]绍兴市人民医院病理科,浙江绍兴312000

出　　处：《中国卫生检验杂志》2015年第1期130-133,138,共5页Chinese Journal of Health Laboratory Technology

基　　金：浙江省医学重点学科建设计划项目(GJSX-010-004)

摘　　要：目的调查本院大肠埃希菌arm A基因的分布定位与耐药谱的关系。方法对氨基糖苷类抗生素耐药的大肠埃希菌检测arm A和intl1。采用质粒接合试验初步定位,基因间重复序列-聚合酶链式反应(ERIC-PCR)进行基因分型。结果 69株大肠埃希菌中共有arm A基因阳性菌株20株,均为ESBL阳性。含有arm A基因的大肠埃希菌intl1阳性率为60.0%,含有5种不同的耐药基因盒,分别携带drf A25、drf A1、drf A12、aad A1、aad A2、sat和blaVEB-1基因。ERICPCR显示arm A阳性大肠埃希菌分为5型,A型为优势克隆株。质粒接合试验发现A克隆株获得阿米卡星耐药接合子,而B、C克隆株均未获得;质粒谱分析发现A克隆株的arm A基因均位于>23 130 bp质粒上。结论 arm A基因广泛存在于大肠埃希菌中,且呈克隆播散。A克隆株具有质粒传播能力,应采取有效措施控制耐药菌的传播。Objective To investigate the relationship between the distribution of 16 S rRNA methylase gene arm A of Escherichia coli（ E. coli） and the drug resistance patterns. Methods The arm A and intl1 of E. coli being resistant to aminoglycoside antibiotics were detected. Using plasmid conjugation experiment for preliminary positioning,and ERIC- PCR for genotyping.Results Twenty gene arm A isolates of 69 strains were all positive for the extended spectrum beta lactamases（ ESBLs）. The positive rate of intl1 in the E. coli carrying arm A was 60. 0%. All the intl1 gene positive strains were divided into five kind gene cassettes,which contained drf A25,drf A1,drf A12,aad A1,aad A2,sat and blaVEB- 1genes. Respectively,arm A positive strains were divided into five types using ERIC- PCR technology. A genotype was the advantage type. Plasmid conjugation experiment found that A clones obtained Amikacin resistant Transconjugant,but B and C clones didn＇t obtained; The spectrum of plasmid analyzed that the arm A gene of A clone located on a plasmid with a similar size of approximately more than 23 130 bp. Conclusion The study showed that gene arm A were prevalent in E. coli and widely spread as clones. Especially,the A clone can transmit by plasmid. So the effective infection control measure should be conducted in order to control the outbreak of resistant bacteria.

关 键 词：大肠埃希菌 16S rRNA甲基化酶 整合子类 

分 类 号：R378.21[医药卫生—病原生物学]