合肥地区结核分枝杆菌利福平耐药基因rpoB突变特征研究

目的:了解合肥地区结核分枝杆菌利福平(RFP)耐药株rpoB基因突变特点。方法:应用PCR-直接测序法对合肥地区肺结核病人痰液中分离的90株结核分枝杆菌的rpoB基因629 bp(包括rpoB基因利福平耐药决定区(RRDR)的81 bp)序列进行测定分析。结果:90株结核分枝杆菌中69株对RFP耐药,21株对RFP敏感;69株耐利福平临床分离株中53株发生rpoB基因突变,突变率为76.8%;突变发生在531位丝氨酸的31株,发生率为44.9%,发生在526位组氨酸的8株,发生率为11.6%;还有6株发生了联合突变,发生率为8.7%。21株敏感株中1株rpoB基因发生突变,突变位点是533位亮氨酸。结论:合肥地区结核分枝杆菌利福平耐药基因rpoB基因的RRDR发生了突变,其中531位丝氨酸和526位组氨酸是最常见的突变位点。

Study on rpoB mutation associated with rifampicin resistance in Mycobacterium tuberculosis isolated from Hefei

Objective: To investigate the mutation characteristics of rpoB gene in rifampicin(RFP)-resistant strains of Mycobacterium tuberculosis isolated from Hefei.Methods: 629 bp DNA fragment(including 81 bp in RFP resistance deteremination region) of rpoB gene in 90 strains of M.tuberculosis isolated from the sputum of tuberculosis patients in Hefei was analyzed DNA sequencing.Results: It was found 69 strains were RFP-resistant and 21 strains were RFP-susceptible in 90 strains of M.tuberculosis.In the 69 RFP-resistant strains,rpoB gene mutations occurred in 53 strains,mutation rate was 76.8%,point mutation mainly occurred at the 531 serine(31 strains,44.9%) and the 526 histidine(8 strains,11.6%),combinations of mutations were found in 6 strains(8.7%).In the 21 RFP-susceptible strains,only 1 strain was found rpoB gene mutation,the mutation point was the 533 leucine.Conclusion: In Hefei area,RRDR of rpoB gene in Mycobacterium tubericulosis had mutations,the 531 serine and 526 histidine were the most common mutation points.