Role of embCAB gene mutations in ethambutol resistance in Mycobacterium tuberculosis isolates from India.

  • Gaurav Pratap Singh Jadaun, Ram Das, Prashant Upadhyay, D S Chauhan, V D Sharma, V M Katoch
  • Published 2009 in International journal of antimicrobial agents

Abstract

In the present study, ethambutol (EMB) resistance-associated mutations were characterised in the embCAB genes of clinical isolates of Mycobacterium tuberculosis (MTB) collected in India. Thirty MTB isolates were tested for their susceptibility to first-line antitubercular drugs using the Löwenstein-Jensen proportion method, and EMB minimum inhibitory concentrations of MTB isolates were determined by the resazurin microtitre assay. Sequencing of various regions of the embCAB genes was performed to identify EMB resistance-associated mutations. Mutations of embB306 were detected in 15 of 23 EMB-resistant MTB isolates. Three EMB-resistant isolates had mutations at codon 270 of the embC gene, two of which also harboured embB306 mutations. No mutation was identified in the embA gene. All seven EMB-sensitive MTB isolates had the wild-type embCAB sequence. In summary, embB306 mutations were associated with EMB resistance, and mutation at codon 270 of the embC gene may contribute to high-level EMB resistance in some MTB isolates.

DOI: 10.1016/j.ijantimicag.2008.10.017

Cite this paper

@article{Jadaun2009RoleOE, title={Role of embCAB gene mutations in ethambutol resistance in Mycobacterium tuberculosis isolates from India.}, author={Gaurav Pratap Singh Jadaun and Ram Das and Prashant Upadhyay and D S Chauhan and V D Sharma and V M Katoch}, journal={International journal of antimicrobial agents}, year={2009}, volume={33 5}, pages={483-6} }