【摘要】 目的　研究脓肿分支杆菌对利福平的耐受程度 ,并观察不同耐药性的细菌是否存在rpoB基因的突变和突变的性质。方法　用生化法和聚合酶链反应 限制片段长度多态性 (PCR RFLP)法鉴定 15株脓肿分支杆菌菌种 ,测定这些临床菌株及标准株ATCC19977对利福平的最低抑菌浓度(MIC) ,并用PCR方法扩增rpoB的部分序列 ,直接测序分析。结果　 15株脓肿分支杆菌有 1株敏感 ,其余 14株与标准株均有较高的MIC ;各菌株rpoB基因突变集结区和第 14 6位密码子的核苷酸序列虽有不同 ,但其编码的氨基酸序列在所有菌株中均相同 ,而且与结核分支杆菌标准株同一部位的氨基酸序列也完全一致。结论　脓肿分支杆菌对利福平具有较高的耐受性 ,其耐药机制并不是由于这些部位的rpoB基因的变异所致。更多还原

【Abstract】 Objective To observe the resistance of Mycobacterium abscessus to rifampin and to investigate if there is any mutation of rpoB gene in strains with high minimal inhibitory concentration (MIC). Methods Mycobacterium abscessus was identified with both biochemical methods and PCR-RFLP. The MICs of rifampin to all the clinical strains and the type strain ATCC19977 were determined. DNA sequences were obtained from a 1272 bp fragment of the rpoB gene from either low or high rifampin MIC strains using PCR amplification. Results Only one strain had low MICs of 4 μg/ml. MICs of all the other 14 strains, as well as the type stain were above 128-256 μg/ml. Although there were some differences in nucleotide sequence of rpoB gene, all strains had the same amino acid sequence without any mutations. Conclusions Mycobacterium abscessus showed a high resistance to rifampin.Mutations of rpoB gene do not seem to be the responsible mechanism.更多还原