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Characterization of an interplay between a Mycobacterium tuberculosis MazF homolog, Rv1495 and its sole DNA topoisomerase I.

ABSTRACT: The MazEF systems are thought to contribute to the capacity for long-term dormancy observed in the human pathogen, Mycobacterium tuberculosis. However, except for their functions as mRNA interferases, little is known regarding any additional cellular functions of these systems in the pathogen. In the present study, we observed a negative interplay between MazF protein Rv1495 and the sole M. tuberculosis DNA topoisomerase I (MtbTopA) with respect to protein functions. Through its C-terminal domain, MtbTopA physically interacted with and inhibited the mRNA cleavage activity of Rv1495. Rv1495, in turn, inhibited the DNA cleavage activity of MtbTopA as well as its function of relaxation of supercoiled DNA. An N-terminus fragment of Rv1495, designated Rv1495-N(29-56), lost mRNA cleavage activity, but retained a significant physical interaction and inhibitory effect on TopA proteins from both M. tuberculosis and M. smegmatis. This fragment, although less effective than the full-length protein, was able to inhibit mycobacterial growth when expressed through a recombinant plasmid in M. smegmatis. The Rv1495 physically interacted with the M. smegmatis TopA both in vitro and in vivo. Our findings imply that MazEF systems can affect bacterial survival by a novel mechanism that allows direct modulation of M. tuberculosis topoisomerase I.

SUBMITTER: Huang F

PROVIDER: S-EPMC3001090 | biostudies-other | 2010 Dec

REPOSITORIES: biostudies-other

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Characterization of an interplay between a Mycobacterium tuberculosis MazF homolog, Rv1495 and its sole DNA topoisomerase I.

Huang Feng F He Zheng-Guo ZG

Nucleic acids research 20100819 22

The MazEF systems are thought to contribute to the capacity for long-term dormancy observed in the human pathogen, Mycobacterium tuberculosis. However, except for their functions as mRNA interferases, little is known regarding any additional cellular functions of these systems in the pathogen. In the present study, we observed a negative interplay between MazF protein Rv1495 and the sole M. tuberculosis DNA topoisomerase I (MtbTopA) with respect to protein functions. Through its C-terminal domai ...[more]

PMID: 20724443

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Dataset Information

Characterization of an interplay between a Mycobacterium tuberculosis MazF homolog, Rv1495 and its sole DNA topoisomerase I.

Publications

Characterization of an interplay between a Mycobacterium tuberculosis MazF homolog, Rv1495 and its sole DNA topoisomerase I.

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