| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Genetics and Molecular Biology |
Division of Mycobacterial Research, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK1
Author for correspondence: K. G. Papavinasasundaram. Tel: +44 20 8959 3666. Fax: +44 20 8913 8528. e-mail: kpapavi{at}nimr.mrc.ac.uk
In mycobacteria, as in most bacterial species, the expression of RecA is induced by DNA damage. However, the authors show here that the kinetics of recA induction in Mycobacterium smegmatis and in Mycobacterium tuberculosis are quite different: whilst maximum expression in M. smegmatis occurred 3–6 h after addition of a DNA-damaging agent, incubation for 18–36 h was required to reach peak levels in M. tuberculosis. This is despite the fact that the M. tuberculosis promoter can be activated more rapidly when transferred to M. smegmatis. In addition, it is demonstrated that in both species the DNA is sufficiently damaged to give maximum induction within the first hour of incubation with mitomycin C. The difference in the induction kinetics of recA between the two species was mirrored by a difference in the levels of DNA-binding-competent LexA following DNA damage. A decrease in the ability of LexA to bind to the SOS box was readily detected by 2 h in M. smegmatis, whilst a decrease was not apparent until 18–24 h in M. tuberculosis and then only a very small decrease was observed.
Keywords: LexA, SOS induction, mycobacteria
a Present address: Trescowthick Research Laboratories, Peter MacCallum Cancer Institute, Locked Bag 1, A’Beckett Street, Melbourne VIC 8006, Australia.
b Present address: London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
This article has been cited by other articles:
|
|
 |
|
  D. M. O'Sullivan, J. Hinds, P. D. Butcher, S. H. Gillespie, and T. D. McHugh Mycobacterium tuberculosis DNA repair in response to subinhibitory concentrations of ciprofloxacin J. Antimicrob. Chemother., September 16, 2008; (2008) dkn387v1. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 P. C. Brooks, L. F. Dawson, L. Rand, and E. O. Davis The Mycobacterium-Specific Gene Rv2719c Is DNA Damage Inducible Independently of RecA. J. Bacteriol., August 1, 2006; 188(16): 6034 - 6038. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. M. Roux, N. J. Booth, B. H. Bellaire, J. M. Gee, R. M. Roop II, M. E. Kovach, R. M. Tsolis, P. H. Elzer, and D. G. Ennis RecA and RadA Proteins of Brucella abortus Do Not Perform Overlapping Protective DNA Repair Functions following Oxidative Burst. J. Bacteriol., July 1, 2006; 188(14): 5187 - 5195. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. B. Arnvig, B. Gopal, K. G. Papavinasasundaram, R. A. Cox, and M. J. Colston The mechanism of upstream activation in the rrnB operon of Mycobacterium smegmatis is different from the Escherichia coli paradigm Microbiology, February 1, 2005; 151(2): 467 - 473. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. B. Arnvig, S. Pennell, B. Gopal, and M. J. Colston A high-affinity interaction between NusA and the rrn nut site in Mycobacterium tuberculosis PNAS, June 1, 2004; 101(22): 8325 - 8330. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. K. Gopaul, P. C. Brooks, J.-F. Prost, and E. O. Davis Characterization of the Two Mycobacterium tuberculosis recA Promoters J. Bacteriol., October 15, 2003; 185(20): 6005 - 6015. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Unniraman, M. Chatterji, and V. Nagaraja A hairpin near the 5' end stabilises the DNA gyrase mRNA in Mycobacterium smegmatis Nucleic Acids Res., December 15, 2002; 30(24): 5376 - 5381. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. M. Dullaghan, P. C. Brooks, and E. O. Davis The role of multiple SOS boxes upstream of the Mycobacterium tuberculosis lexA gene - identification of a novel DNA-damage-inducible gene Microbiology, November 1, 2002; 148(11): 3609 - 3615. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Unniraman, M. Chatterji, and V. Nagaraja DNA Gyrase Genes in Mycobacterium tuberculosis: a Single Operon Driven by Multiple Promoters J. Bacteriol., October 1, 2002; 184(19): 5449 - 5456. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. O. Davis, E. M. Dullaghan, and L. Rand Definition of the Mycobacterial SOS Box and Use To Identify LexA-Regulated Genes in Mycobacterium tuberculosis J. Bacteriol., June 15, 2002; 184(12): 3287 - 3295. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| INT J SYST EVOL MICROBIOL | MICROBIOLOGY | J GEN VIROL |
| J MED MICROBIOL | ALL SGM JOURNALS | |
