Novel mutations in katG gene of a clinical isolate of isoniazid-resistant Mycobacterium tuberculosis

Purkan, Ihsanawati, Yana M. Syah, Debbie S. Retnoningrum, Achmad S. Noer, Shigeru Shigeoka, Dessy Natalia

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)

Abstract

Most of isoniazid-resistant Mycobacterium tuberculosis evolved due to mutation in the katG gene encoding catalase-peroxidase. A set of new mutations, namely T1310C, G1388T, G1481A, T1553C, and A1660G, which correspond to amino acid substitutions of L437P, R463L, G494D, I518T, and K554E, in the katG gene of the L10 clinical isolate M. tuberculosis was identified. The wild-type and mutant KatG proteins were expressed in Escherichia coli BL21(DE3) as a protein of 80 kDa based on sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis. The mutant KatG protein exhibited catalase and peroxidase activities of 4. 6% and 24. 8% toward its wild type, respectively, and retained 19. 4% isoniazid oxidation activity. The structure modelling study revealed that these C-terminal mutations might have induced formation of a new turn, perturbing the active site environment and also generated new intramolecular interactions, which could be unfavourable for the enzyme activities.

Original languageEnglish
Pages (from-to)41-47
Number of pages7
JournalBiologia (Poland)
Volume67
Issue number1
DOIs
Publication statusPublished - Feb 2012

Keywords

  • Mycobacterium tuberculosis
  • catalase-peroxidase
  • clinical isolate
  • isoniazid resistance
  • katG

Fingerprint

Dive into the research topics of 'Novel mutations in katG gene of a clinical isolate of isoniazid-resistant Mycobacterium tuberculosis'. Together they form a unique fingerprint.

Cite this