金黄色葡萄球菌脉冲场凝胶电泳及耐药表型分析

Staphylococcus aureus pulsed-field gel electrophoresis and drug resistance phenotype analysis

目的研究金黄色葡萄球菌食品分离株和食物中毒分离株的分子生物学特征,结合耐药表型结果,分析菌株间的同源性及耐药关系。方法选取分离自食品、食物中毒食品及病人吐泻物的40株金黄色葡萄球菌,通过脉冲场凝胶电泳(PFGE)方法,用限制性内切酶Sma I酶酶切细菌基因组进行脉冲场凝胶电泳分型;采用K-B纸片扩散法对40株金黄色葡萄球菌进行10类12种抗生素的药敏试验。结果 40株金黄色葡萄球菌通过PFGE分为8个簇,共26种带型,同起食物中毒分离株有聚集,不同年份不同食物来源的菌株也有聚集;分离株对青霉素G高度耐药,耐药率为95%(38/40),且存在多重耐药;不同分子簇及相同分子簇内菌株耐药表型存在较大差异。结论脉冲场凝胶电泳适用于分析金黄色葡萄球菌菌株之间的相关性、同源性,结合菌株的耐药表型可以提示高风险食品及指导临床合理用药。

Objective To study the molecular characteristics of Staphylococcus aureus isolated from food and food poisoning related samples, and analyze the homology and drug resistance among the strains. Methods A total of 40 strains of Staphylococcus aureus isolated from food and food poisoning-related samples were selected. Pulsed-field gel electrophoresis typing by restriction endonuclease enzyme Sma I was used. A total of 12 kinds of antibiotics were used to do the drug test by using K-B disk diffusion method. Results A total of 40 strains Staphylococcus aureus were divided into eight clusters, 26 types by PFGE, there was isolates from gathered cases among one food poisoning and different years, different food poisoning, the isolates were highly resistant to penicillin G, the rate of resistance drug was 95% （38/40）, with multiple drug resistance; There was an obvious difference among resistant phenotype in different molecular clusters and the same molecular cluster. Conclusion Pulsed-field gel electrophoresis is applicable to the analysis of correlation and homology of Staphylococcus aureus.