Characterization of the katG gene encoding a catalase-peroxidase required for the isoniazid susceptibility of Mycobacterium tuberculosis.

Abstract

The isoniazid susceptibility of Mycobacterium tuberculosis is mediated by the product of the katG gene which encodes the heme-containing enzyme catalase-peroxidase. In this study, the chromosomal location of katG has been established and its nucleotide sequence has been determined so that the primary structure of catalase-peroxidase could be predicted. The M. tuberculosis enzyme is an 80,000-dalton protein containing several motifs characteristic of peroxidases and shows strong similarity to other bacterial catalase-peroxidases. Expression of the katG gene in M. tuberculosis, M. smegmatis, and Escherichia coli was demonstrated by Western blotting (immunoblotting). Homologous genes were detected in other mycobacteria, even those which are naturally insensitive to isoniazid.

• Authors: B Heym, Y Zhang, S Poulet, D Young, S T Cole
• Journal: Journal of bacteriology (J Bacteriol) Vol. 175 Issue 13 Pg. 4255-9 (Jul 1993) ISSN: 0021-9193 [Print] United States
• PMID: 8320241 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Bacterial Proteins
• Peroxidases
• catalase HPI
• Isoniazid

Topics

• Amino Acid Sequence
• Bacterial Proteins
• Chromosome Mapping
• Drug Resistance, Microbial
• Genes, Bacterial (genetics)
• Isoniazid (pharmacology)
• Molecular Sequence Data
• Mycobacterium (enzymology, genetics)
• Mycobacterium tuberculosis (drug effects, enzymology, genetics)
• Peroxidases (genetics, immunology)
• Sequence Analysis, DNA
• Sequence Homology, Amino Acid