Mutation of DNA fragment of rpoB gene in different degrees of rifampin-resistance in Mycobacterium tuberculosis / 中国实用内科杂志

ABSTRACT

Objective To study the mutation of DNA fragment of rpoB gene in different degrees of rifampin-resistance in Mycobacterium tuberculosis.Methods DNA fragment of rpoB gene in Mycobacterium tuberculosis was sequenced,including 32 low-level (R50) rifampin-resistant strains (50?g/mL rifampin-resistant),22 high-level (R250) rifampin-resistant strains (250?g/mL rifampin-resistant),10 (R0)rifampin-sensative strains and 1 H 37 Rv strain.Results No mutation was detected in 10 rifampin-sensative strains and 1 H 37 Rv strain;25(78.1%)rifampin-resistant strains had mutations in R50 and 21(95.5%)rifampin-resistant strains had mutations in R250(P=0.170).The mutatione points were distributed disorderly in R50.The 531-Ser mutation(57.1%)and joint mutation(23.8%)were more in R250 than those in R50.Conclusion The frequency of mutation in the rpoB gene of rifampin-resistant strain is higher.The mutation points are distributed disorderly in R50.The 531-Ser mutation(57.1%)and joint mutation(23.8%)are major mutative characteristics in R250.