解脲脲原体23SrRNA位点突变与大环内酯类药物耐药的关系

摘要

目的 探讨解脲脲原体(Ureaplasma urealyticum,Uu)对大环内酯类药物的耐药机制.方法 临床分离的20株对大环内酯药物不同耐药表型的Uu,其中6株为敏感株,采用PCR、DNA测序方法检测其23SrRNA基因序列,与对大环内酯类药物敏感的标准菌株ATCC 27618及基因库中的标准菌株基因序列对比分析查找突变位点,并分析突变位点与耐药表型的关系.结果 Uu菌株23SrRNA突变位点与其对大环内酯药物耐药表型对照分析结果表明,5株耐药表型为岁红霉素(R)和阿奇霉素(R)的菌株中均存在C2243N(TorC)变异,其中1株伴有A2149C,A2181T;9株耐药表型为罗红霉素(R)和阿齐霉素(I)的Uu菌株和6株表型为罗红霉素(S)和阿奇霉素(S)的Uu菌株中均存在A2149C,A2181T的变异.结论 初步判断Uu 23SrRNA C2243N(T或C)变异可能导致其对罗红霉素、阿奇霉素产生耐药,具体的相关性尚需大样本深入研究.%Objective To investigate the mechanisms of ureaplasma urealyticum(Uu)resistance to macrolide antibiotics.Methods Twenty strains of clinical isolates of Uu with variable resistance to macrolides and reference strain ATCC 27618 were examined for mutations in 23SrRNA.Results As compared with the sequence of reference strain ATCC 27618 and GenBank,three mutations were found in 23SrRNA of Uu clinical isolates.C2243N(TorC)was found in the 23SrRNA in 5 strains with the phenotype resistance to roxithromvcin and azithromycin.A2149C and A2181T were found in the 23SrRNA in 9 strains with the phenotype resistance to roxithromycin and midrange resistance to azithromycin,and 6 strains with the phenotype of sensitivity to roxithromyein and azithromycin.Conclusions The mechanisms of Uu resistance to roxithromycin and azithromycin may be related with the mutations in 23SrRNA.It may warrant further investigation.