Study on Molecular Mechanism of Isoniazid Resistance of Mycobacterium Tuberculosis

Objective To observe the mutations of katG in Mycobacterium tuberculosis isoniazid-resident isolates,to research their l value in isoniazid resistanceMethods Analyzing the mutations of katG in 72 Mycobacterium tuberculosis with PCR-SSCP.32 isoniazid susceptible Mycobacterium tuberculosis clinical isolates and 40 isoniazid resistant isolates with Mycobacterium tuberculosis H37RV reference strains as control group.Results Amplification was abserved all of isoniazid susceptible Mycobacterium tuberculosis clinical isolates.Among 40 isoniazid resistant chinial isolates,15 isolates diaplayed the same patterns as H37RV and 25 isolates showed PCR-SSCP diffirent from that of H37RV.About 62.5 percent isoniazid-resident isolates showed mutation or deletion of katG gene.Conclusion The changes of katG gene are associated with isoniazid residenance.PCR-SSCP technique will be useful to rapidly screen gene mutation of isoniazid resistant Mycobacterium tuberculosis.