耐甲氧西林金黄色葡萄球菌血液分离株毒力基因研究  

Virulence genes in methicillin-resistant Staphylococcus aureus isolated from blood specimens

作　　者：张巧丽[1] 马红映[1] 张筠[1] 邓在春[1] 虞亦鸣[1] 

机构地区：[1]宁波大学医学院附属医院呼吸内科,浙江宁波315020

出　　处：《中华医院感染学杂志》2016年第21期4859-4862,共4页Chinese Journal of Nosocomiology

基　　金：浙江省自然科学基金(Y15H010008)

摘　　要：目的分析医院内MRSA血液分离菌株分子生物学特征,了解MRSA毒力的分子机制。方法对医院2012年4月-12月自血液分离19株MRSA,采用聚合酶链式反应(PCR)在19株菌株中检测55种毒力基因;随机选取上述PCR阳性产物进行测序,测序结果用Chromas软件直接做BLAST Search比对。结果本组金黄色葡萄球菌中黏附毒素、细胞毒素、侵袭性酶、超抗原、外毒素、荚膜抗原等六大类毒力基因均有检出,55种毒力基因中检出率为100%的毒力基因有clfB、isdA、isdB、isdC、hla、hld、hlg2、set11,有15种未检出,分别为hlg、lukM、sak、eta、seb、sec、sed、see、seh、sej、sel、sep、set2、set4、set5;本组单个MRSA菌株毒力基因检出个数的中位数为28。结论本组MRSA菌表现出单个菌株同时携带多种毒力基因的特点,提示MRSA菌能从黏附定植、杀白细胞、扰乱宿主免疫功能、破坏宿主组织结构等多方面损伤宿主,从而致病。了解MRSA毒力基因的携带情况将为治疗MRSA药物的开发提供分子生物学依据。OBJECTIVE To analyze the molecular biological characteristics of clinical MRSA isolates from blood specimens and understand the molecular mechanisms of virulence factors in the MRSA. METHODS A total of 19 strains of MRSA were isolated from blood specimens from Apr 2012 to Dec 2012, then the 55 kinds of virulence genes in the 19 strains were detected by using polymerase-chain-reaction （PCR）, the PCR positive products were randomly extracted and sequenced, and the sequencing results were compared with the BLAST search with the use of Chromas software. RESULTS Totally 6 categories of virulence genes, including the adhesin, cytotoxin, invasive enzyme, superantigen, exotoxin, capsular antigen, were detected in this group of S. aureus strains. Among the 55 kinds of virulence genes, the detection rates of clfB, isdA, isdB, isdC, hla, hld, hlg2, and setll were 100% however, 15 kinds of genes, including hlg , lukM, sak, eta, seb, sec, sed, see, she, sej, sel, sep, set2, set4, and set5 were not detected. The median of the virulence genes detected in one singe MRSA strain was 28. CONCLUSION The study concludes that multiple virulence genes are detected in one single MRSA strain, indica- ting that the MRSA strains could harm the host via the ability of adhesion and colonization, cytocidal effect, distur- bing the hosts＂ immunity, and destruction of hosts＂ tissue structure and then cause disease. The study of the viru- lence genes in the MRSA strains may provide molecular biological bases for development of drugs for treatment of MRSA infection.

关 键 词：耐甲氧西林金黄色葡萄球菌 分子生物学 毒力因子 

分 类 号：R378.11[医药卫生—病原生物学]