Detection of Isoniazid-Resistant Mycobacterium tuberculosis Strains by a Multiplex Allele-Specific PCR Assay Targeting katG Codon 315 Variation

AUTOR(ES)

Mokrousov, Igor

FONTE

American Society for Microbiology

RESUMO

We describe a simple multiplex allele-specific (MAS)-PCR assay to detect mutations in the second base of the katG gene codon 315, including AGC→ACC and ACA (Ser→Thr) substitutions that confer resistance to isoniazid (INH) in Mycobacterium tuberculosis clinical isolates. The 315 ACC allele is found in the majority of Inhr strains worldwide, especially in areas with a high incidence of tuberculosis. The 315 ACA allele is characteristic of the New York City multidrug-resistant (MDR) strain W and its progenies in the United States. The mutations in katG315 are revealed depending on the presence or absence of an indicative fragment amplified from the wild-type allele of this codon. Initially optimized on the purified DNA samples, the assay was then tested on crude cell lysates and auramine-stained sputum slide preparations with the same reproducibility and interpretability of profiles generated by agarose gel electrophoresis. The MAS-PCR assay can be used for the detection of resistance to INH in clinical laboratories in regions with a high prevalence of MDR M. tuberculosis strains.

Documentos Relacionados

• katG mutations in isoniazid-resistant strains of Mycobacterium tuberculosis are not infrequent.
• Detection of Ethambutol-Resistant Mycobacterium tuberculosis Strains by Multiplex Allele-Specific PCR Assay Targeting embB306 Mutations
• katG mutations in isoniazid-resistant Mycobacterium tuberculosis isolates recovered from Finnish patients.
• Characterization of the katG and inhA genes of isoniazid-resistant clinical isolates of Mycobacterium tuberculosis.
• Mutations in katG gene sequences in isoniazid-resistant clinical isolates of Mycobacterium tuberculosis are rare.