【摘要】 目的研究结核分枝杆菌假设蛋白Rv0341编码基因iniB的多态性,确认其保守性,分析依赖利福平结核分枝杆菌(依R菌)在利福平(R)培养管中Rv0341高表达的可能原因。方法用大肠埃希菌做为阴性对照,提取依R菌(14株)、耐R菌(23株)、R敏感的结核分枝杆菌(12株)、结核分枝杆菌标准株H37Rv及BCG(共51株)的细菌基因组DNA,利用PCR自基因组DNA中扩增iniB基因,通过ApaⅠ/EcoRⅤ、KpnⅠ/SmaⅠ双酶切,琼脂糖凝胶电泳检测其带型,对iniB基因进行限制性片段长度多态性分析并测序。结果实验组中iniB基因的酶切图谱完全相同,测序结果亦证实iniB基因无突变。结论 iniB基因在对R依赖、耐药和敏感等不同类型的结核分枝杆菌中是相对保守的;依R菌在Rv0341蛋白表达方面的差异可能是RNA转录差异或利福平诱导的结果。更多还原

【Abstract】 Objective To investigate the polymorphism and conservatism of iniB gene that encodes the hypothetical protein Rv0341 of M.tuberculosis,find the possible reason that Rv0341 highly expressed when M.tuberculosis was cultured in the medium containing rifampin.Methods E.coli was used as negative control,the iniB genes from 14 rifampin-dependent M.tuberculosis isolates,23 rifampin-resistant isolates,12 rifampin-sensitive isolates,M.tuberculosis H37Rv and BCG were amplified by PCR,and then digested by restriction enzyme Apa Ⅰ/EcoRⅤ,Kpn Ⅰ/Sma Ⅰ,electrophoresed in 1% agarose.The results were analysed by RFLP.Results The 1440 bp iniB gene was successfully cloned.No polymorphism of iniB genes from M.tuberculosis isolates were found by RFLP analysis and sequencing.Conclusions The iniB gene was highly conservative in rifampicin-dependent,resistant and sensitive M.tuberculosis isolates.The high expression of Rv0341 protein was caused by the differences in transcription and rifampicin induction.更多还原