Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Biol Chem. 2009 Jan 2;284(1):276-83. doi: 10.1074/jbc.M805061200. Epub 2008 Oct 24.

Structure and proposed activity of a member of the VapBC family of toxin-antitoxin systems. VapBC-5 from Mycobacterium tuberculosis.

Author information

  • 1UCLA-DOE Institute of Genomics and Proteomics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095-1570, USA.

Abstract

In prokaryotes, cognate toxin-antitoxin pairs have long been known, but no three-dimensional structure has been available for any given complex from Mycobacterium tuberculosis. Here we report the crystal structure and activity of a member of the VapBC family of complexes from M. tuberculosis. The toxin VapC-5 is a compact, 150 residues, two domain alpha/beta protein. Bent around the toxin is the VapB-5 antitoxin, a 33-residue alpha-helix. Assays suggest that the toxin is an Mg-enabled endoribonuclease, inhibited by the antitoxin. The lack of DNase activity is consistent with earlier suggestions that the complex represses its own operon. Furthermore, analysis of the interactions in the binding of the antitoxin to the toxin suggest that exquisite control is required to protect the bacteria cell from toxic VapC-5.

PMID:
18952600
[PubMed - indexed for MEDLINE]
PMCID:
PMC2610494
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk