复合PCR鉴别葡萄球菌及其多重耐药基因

目的　建立既可鉴别金黄色葡萄球菌又可同时检测其耐药基因的分子诊断方法。方法　对应于femB、mecA、ileS基因的 3对引物与快速提取的单菌落模板DNA进行单管同步扩增 ,电泳观察PCR片段 ;mecA、ileS耐药基因扩增结果分别与苯唑西林、莫匹罗星药敏试验对比 ,分析菌株的耐药性。结果　检测femB基因可快速特异性地筛选出金黄色葡萄球菌 ,mecA基因的检出与常规药敏试验鉴定耐甲氧西林葡萄球菌 (MRS)的结果基本一致 ,而拥有ileS基因的全部葡萄球菌分离株对莫匹罗星耐药。结论　复合PCR可快速敏感地从葡萄球菌中区分金黄色葡萄菌 ,并同时检出MRSA和耐莫匹罗星的多重耐药菌株。

Identification of Staphylococcus aureus and detection of its multiple-resistant genes by multiplex PCR

Objective To establish a multiplex PCR assay for the identification of S. aureus from the Staphylococcus isolates and for the simultaneous detection of clinically relevant antibiotic-resistant genes in these isolates at the species level.Methods Simultaneous amplification of the 310bp,456bp,and 651bp regions of the mecA,ileS and femB genes were respectively performed by using the rapidly extracted DNA from single Staphylococcus colony in single tube.The mecA and ileS fragments amplified by PCR were compared to those in antibiotic susceptibility tests of methicillin and mupirocin,respectively,and the resistance phenotypes were determined.Results The PCR detection of femB fragment allowed the specific identification of S.aureus from the Staphylococcus isolates.The PCR detection of mecA fragment showed a consistent result with that of methicillin-resistant test and indicated the mecA gene may be used as a useful molecular marker for diagnosis of methicillin-resistant Staphylococcus (MRS).The Staphylococcus isolates with ileS gene appeared to be mupirocin-resistance.Conclusion The multiplex PCR offers a rapid,sensitive test to identify S.aureus from the Staphylococcus isolates.MRSA and mupirocin-resistant genes in clinical isolates can be detected by the PCR assay simultaneously.