This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Rinken, R Articles by Wackernagel, W Search for Related Content PubMed PubMed Citation Articles by Rinken, R Articles by Wackernagel, W

 Previous Article  |  Next Article 

J Bacteriol. 1992 February; 174(4): 1172-1178

research-article

Inhibition of the recBCD-dependent activation of Chi recombinational hot spots in SOS-induced cells of Escherichia coli.

Genetik, Fachbereich Biologie, Universität Oldenburg, Germany.

ABSTRACT

Nucleotide sequences called Chi (5'-GCTGGTGG-3') enhance homologous recombination near their location by the RecBCD enzyme in Escherichia coli (Chi activation). A partial inhibition of Chi activation measured in lambda red gam mutant crosses was observed after treatment of wild-type cells with DNA-damaging agents including UV, mitomycin, and nalidixic acid. Inhibition of Chi activation was not accompanied by an overall decrease of recombination. A lexA3 mutation which blocks induction of the SOS system prevented the inhibition of Chi activation, indicating that an SOS function could be responsible for the inhibition. Overproduction of the RecD subunit of the RecBCD enzyme from a multicopy plasmid carrying the recD gene prevented the induced inhibition of Chi activation, whereas overproduction of RecB or RecC subunits did not. It is proposed that in SOS-induced cells the RecBCD enzyme is modified into a Chi-independent recombination enzyme, with the RecD subunit being the regulatory switch key.

This article has been cited by other articles:

• Amundsen, S. K., Taylor, A. F., Smith, G. R. (2002). A Domain of RecC Required for Assembly of the Regulatory RecD Subunit Into the Escherichia coli RecBCD Holoenzyme. Genetics 161: 483-492 [Abstract] [Full Text]  
• Quiberoni, A., Biswas, I., El Karoui, M., Rezaiki, L., Tailliez, P., Gruss, A. (2001). In Vivo Evidence for Two Active Nuclease Motifs in the Double-Strand Break Repair Enzyme RexAB of Lactococcus lactis. J. Bacteriol. 183: 4071-4078 [Abstract] [Full Text]  
• Kuzminov, A. (1999). Recombinational Repair of DNA Damage in Escherichia coli and Bacteriophage lambda. Microbiol. Mol. Biol. Rev. 63: 751-813 [Abstract] [Full Text]  
• Taylor, A. F., Smith, G. R. (1999). Regulation of homologous recombination: Chi inactivates RecBCD enzyme by disassembly of the three subunits. Genes Dev. 13: 890-900 [Abstract] [Full Text]