目的 阐明武汉地区结核分枝杆菌分离株氨基糖苷类药物耐药相关基因rpsL和rrs的分子突变特征.方法 从武汉医疗救治中心共收集69株结核分枝杆菌的临床菌株,包括耐链霉素(SM)菌株35株(其中4株同时对卡那霉素耐药)和SM敏感菌株34株(其中全敏感20株).采用PCR直接测序法分析rpsL和rrs基因的分子突变特征.结果 35株SM耐药株中有26株(74.3％)检测到rpsL突变,突变位点集中在第43位和第88位密码子,并发现了1个新的突变类型Lys88Glu；13株耐药株(37.1％)检测到四种不同类型的rrs基因突变,分别为A1401G( 17.1％,6/35)、A514C( 14.3％,5/35)、GI487A(2.9％,1/35)和C517T(2.9％,1/35),1株全敏感菌株的rrs基因发生了C1029T突变.卡那霉素耐药株中只有3株检测到了rrs突变,并发现了一种rrs基因尚未见报道的G1487A突变类型.结论 结核分枝杆菌对氨基糖苷类药物的耐药与rpsL和rrs突变相关,耐药基因突变类型存在地域差异.%Objective To characterize the rpsL and rrs genes of aminoglycoside-resistant clinical isolates of Mycobacterium tuberculosis in Wuhan. Methods Sixty-nine clinical isolates of Mycobacterium tuberculosis were collected from Wuhan Medical Treatment Center, including 35 streptomycin (SM) -resistance isolates (4 were also resistant to kanamycin) and 34 isolates susceptible to SM (20 were pan-susceptible). Mutation characteristics of rpsL and rrs genes were analyzed with PCR direct sequencing. Results Of the 35 SM-resistant clinical isolates, 26 (74.3%) carried mutations in rpsL gene, with rpsL Lys43Arg and Lys88Arg being the most common rpsL mutations, and one new mutation in codon 88 of rpsL (Lys88Glu) was detected. Four types of mutations in rrs gene in 13 resistant isolates (37. 1%) including A1401G (17. 1%, 6/35), A514C (14.2%, 5/35), G1487A (2.9%, 1/35) and C517T (2.9%, 1/35) were revealed, and one pan-susceptible isolate presenting C1029T mutation in rrs gene was detected. The mutations in rrs gene were only found in 3 kanamycin-resistant isolates, and G1487A mutation was detected in rrs gene, which was first reported. Conclusion Aminoglycoside-resistance of Mycobacterium tuberculosis is related to rpsL and rrs gene mutations, and the characteristics of these genes are diverse due to geographical differences.
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