Related Experiment Video
Updated: Aug 23, 2026

Demonstrating a Multi-drug Resistant Mycobacterium tuberculosis Amplification Microarray
Published on: April 25, 2014
Molecular characterization of isoniazid-resistant Mycobacterium tuberculosis clinical strains isolated in the
Laura Herrera1, Azucena Valverde, Pilar Saiz
1Laboratorio de Referencia de Micobacterias, Servicio de Bacteriología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, CP 28220 Madrid, Spain.
Abstract:
The prevalence of mutations in the katG, inhA and oxyR-ahpC genes of isoniazid (INH)-resistant Mycobacterium tuberculosis isolates in the Philippines were determined. Of 306 M. tuberculosis isolates studied, 81 (26.5%) exhibited INH-resistance. Forty-four strains (54.3%) had mutations in the katG gene, eighteen strains (22.2%) had mutations in the putative inhA locus region, seven had mutations in both regions and five strains had mutations in the oxyR-ahpC operon. Only seven strains had no mutations. A total of 71 of the 81 (87.6%) resistant strains and 65 of the 72 (90.3%) INH sensitive randomly selected strains showed amino acid substitution in codon 463 (Arg to Leu) (88.9%). This fact supports the hypothesis that mutations at codon 463 are independent of INH-resistance and are linked to the geographical origins of the strains.
Related Concept Videos
Pulmonary Tuberculosis V
Latent tuberculosis infection occurs when TB bacteria are present in a person's body, but are not causing illness or symptoms. It is not contagious, and preventive treatment is crucial to avoid the progression...
Pulmonary Tuberculosis IV
Several diagnostic approaches are used to detect TB. The conventional method is the Tuberculin Skin Test (TST), also known as the Mantoux test. However, this method has...
Modern Molecular Taxonomy
Tuberculosis
