study of mutations in katg and inha genes by high resolution method in isoniazid resistant mycobacterium tuberculosis isolates

Multiple mutations in katG and inhA identified in Thai isoniazid-resistant Mycobacterium tuberculosis isolates.

A total of 29 Thai multi-drug-resistant/isoniazid-resistant Mycobacterium tuberculosis isolates were analyzed for mutations in katG from codons 254 to 549, inhA promoter and inhA open reading frame by DNA sequencing and single strand conformation polymorphism. Twenty-five multi-drug resistant isolates exhibited single point mutations (17 isolates at Ser315Thr plus Arg463Leu, 1 at Thr308Pro plus...

Isoniazid MIC and KatG Gene Mutations among Mycobacterium tuberculosis Isolates in Northwest of Iran

Objective(s) Isoniazid (INH) is one of the main first line drugs used in treatment of tuberculosis and development of resistance against this compound can result in serious problems in treatment procedures. Resistance to INH is mediated mainly by mutation in KatG gene that is coded for the catalase enzyme. The proportional method for detection of INH-resistance is time consuming due to the slo...

Mutations in katG gene sequences in isoniazid-resistant clinical isolates of Mycobacterium tuberculosis are rare.

In this study, a battery of oligonucleotides was directed toward the katG gene and PCR-single-stranded conformation polymorphism (SSCP) analysis was used to search for katG gene deviations in clinical isolates of Mycobacterium tuberculosis from different geographical regions. Since a complete deletion of the katG gene was not found, it is suggested that deletion is not a major mechanism of ison...

Contribution of dfrA and inhA mutations to the detection of isoniazid-resistant Mycobacterium tuberculosis isolates.

Screening of 127 isoniazid (INH)-resistant Mycobacterium tuberculosis isolates from Singapore for mutations within the dfrA and inhA genes revealed mutations in 0 and 5 (3.9%) isolates respectively, implying that mutations in dfrA do not contribute to the detection of INH-resistant M. tuberculosis and that mutations within inhA are rare. Thirty-seven (29%) of the 127 isolates had no mutations i...

katG mutations in isoniazid-resistant strains of Mycobacterium tuberculosis isolates from Belarusian patients.

The aim of this study was to investigate the frequency, location and type of katG mutations in Mycobacterium tuberculosis strains isolated from patients in Belarus. Mutations in different codons causing resistance to isoniazide in the gene of catalase peroxides (katG) in Belarusian strains was determined. 42 strains of Rif-r and Inhr(MDR) were isolated in different regions of Belarus. Culture s...

Minor Contribution of inhA-15 Mutations to the Rapid Detection of Isoniazid Resistance in Mycobacterium Tuberculosis Isolates