耐利福平结核分支杆菌rpoB基因突变位点的分析

目的 研究上海地区耐利福平结核分支杆菌ropB基因的突变特点，探讨DNA序列分析在药敏测定中的意义。方法 对58株结核分支杆菌rpoB基因片段（约213bp)进行PCR扩增，其中包括核心突变区的69个碱基，并对PCR产物进行DNA测序。其中耐药株36株，敏感株22株。结果 所有58例中，36株耐药株均存在rpoB基因突变，氨基酸突变率531位为47．2％，526位为25．0％，22株敏感株均无突变。结论 rpoB基因核心突变区发生突变是结核分支杆菌对利福平耐药的主要原因，其中531位丝氨酸和526位组氨酸是最常见的突变位点。

Characterization and Rapid Detection of Mutations in RpoB Gene of Rifampin Resistant Mycobacterium Tuberculosis Strains

Purpose To elucidate the characterization of rpoB mutations in rifampin resistant clinical mycobacterium tuberculosis isolates from Shanghai,and explore the significance of DNA sequencing of rpoB gene in the diagnosis of M. tuberculosis resistance to rifampin. Methods 58 isolates of M. tuberculosis including 36 rifampin resistant strains and 22 susceptible strains were studied.A fragment(213 bp)of rpoB gene of all of the 58 isolates was amplified and sequenced,which comprise the 69 bp rifampin resistance determination region. Results All of the 36 rifampin resistant isolates had mutation in the 69 bp region of rpoB gene,and there were no mutations in any of the susceptible strains.The mutation of 531 Ser and 526 His contributed to 47.2% and 25.0% res pectively of all the mutations. Conclusions Mutations in the 69 bp hypervariable region of rpoB are the main reason of M. tuberculosis resistant to rifampin.531 Ser and 526 His are the most common positions of mutations.