ST9型动物源耐甲氧西林金黄色葡萄球菌的分子分型、毒素基因检测及耐药性分析  

Antimicrobial Susceptibility,Virulence Factors and Molecular Typing of Methicillin-resistant Staphylococcus aureus ST9 from Dairy Cow and Swine

作　　者：张强[1] 邢晓楠[1] 王新[1] 王晓[2] 俞英[2] 吴聪明[3] 沈建忠[3] 

机构地区：[1]西北农林科技大学食品科学与工程学院,杨凌712100 [2]中国农业大学动物科技学院,北京100193 [3]中国农业大学动物医学院,北京100193

出　　处：《畜牧兽医学报》2014年第5期853-858,共6页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：国家自然科学基金(31271858);中央高校基本科研业务费专项资金(QN2011139)

摘　　要：为了解动物源耐甲氧西林金黄色葡萄球菌(MRSA)ST9型的耐药表型、毒素基因和分子型,采用琼脂平板稀释法、药敏纸片法、多位点序列分型(multilocus sequence typing,MLST)、SCCmec分型、spa分型和PFGE分型技术分别对12株猪源和6株牛源MRSA ST9进行耐药性、毒素基因和分子分型研究。结果显示这些MRSA ST9型菌株除了对万古霉素100%敏感外,对其余31种抗生素均产生了不同程度的耐药,其耐药率在5.6%~100%;所有菌株(100%)均携带有毒素基因,毒素基因的检测依次为seg(94.4%)、seb(83.3%)、sed(72.2%)、PVL(55.6%)、sei(11.1%)和sea(5.6%),均未检测到ETs、tsst-1、sec、see、seh和sej基因,得到10个毒力基因型;分子型以ST9-SCCmec IVb-t899克隆系为主(17株,94.4%),其次是MRSA-ST9-SCCmec II-t899(1株,5.6%)。PFGE分型证实MRSA ST9存在一定的传播性。本研究MRSA ST9型菌株主要流行ST9-SCCmec IVb-t899克隆系,该克隆系携带较多毒素基因、多重耐药和传播性,给动物和人类健康构成潜在的风险。The aim of this study was to investigate antimicrobial resistance and molecular characteristics of methicillin-resistant Staphylococcus aureus(MRSA)ST 9from dairy herds and swine.MRSA ST9isolates were characterized by antimicrobial susceptibility test,pulsed-field gel electrophoresis(PFGE),spatyping,and SCCmec typing,and were examined by PCR for genes encoding enterotoxins,exfoliative toxins,Panton-Valentine leukocidin(PVL),and toxic shock syndrome toxin 1(Tsst-1).All MRSA ST9isolates were sensitive to vancomycin.But they showed resistance against other 31antibiotics to various degrees ranging from 5.6%to 100%.In addition,100% of isolates were positive for one or more toxin genes tested.The four most predominant toxin genes were seg(94.4%),seb(83.3%),sed(72.2%)and PVL(55.6%),fol-lowed by sei(11.1%)and,sea(5.6%).ETs,Tsst-1,sec,see,sehand sej genes were not detected.MRSA ST9isolates belonged to ST9-SCCmec IVb-t899(94.4%)and ST9-SCCmec II-t899(5.6%).PFGE suggested potential transmission of MRSA ST9strains in different farms.Many MRSA ST9-SCCmec IVb-t899isolates harbored multiple toxin genes and exhibited multiple antimicrobial resistance.The presence of MRSA ST9strains in these animals poses a potential threat to animal and human health.

关 键 词：MRSA ST9 耐药性 毒素基因 分子型 

分 类 号：R378.11[医药卫生—病原生物学]