Journal
JOURNAL OF BIOLOGICAL CHEMISTRY
Volume 289, Issue 40, Pages 27640-27652Publisher
AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
DOI: 10.1074/jbc.M114.577924
Keywords
DNA-binding Protein; DNA Recombination; DNA Transformation; DNA-Protein Interaction; Protein-DNA Interaction
Categories
Funding
- Ministerio de Economia y Competitividad, Direccion General de Investigacion [FU2012-39879-C02-01]
- Comunidad de Madrid [S2009MAT-1507]
- International Fellowship Programme of La Caixa Foundation (La Caixa/Centro Nacional de Biotecnologia)
Ask authors/readers for more resources
Background: ATP-bound RecA cannot catalyze DNA recombination without crucial accessory factors. Results: DprA facilitates RecA assembly onto SsbA- or SsbB-coated single-stranded DNA, but only DprA and SsbA enable RecAATP to mediate strand exchange. Conclusion: RecAATP transition to an active state requires DprA and SsbA. Significance: DprA and SsbA may serve as a two-component mediator during chromosomal transformation. Bacillus subtilis competence-induced RecA, SsbA, SsbB, and DprA are required to internalize and to recombine single-stranded (ss) DNA with homologous resident duplex. RecA, in the ATPMg(2+)-bound form (RecAATP), can nucleate and form filament onto ssDNA but is inactive to catalyze DNA recombination. We report that SsbA or SsbB bound to ssDNA blocks the RecA filament formation and fails to activate recombination. DprA facilitates RecA filamentation; however, the filaments cannot engage in DNA recombination. When ssDNA was preincubated with SsbA, but not SsbB, DprA was able to activate DNA strand exchange dependent on RecAATP. This work demonstrates that RecAATP, in concert with SsbA and DprA, catalyzes DNA strand exchange, and SsbB is an accessory factor in the reaction. In contrast, RecAdATP efficiently catalyzes strand exchange even in the absence of single-stranded binding proteins or DprA, and addition of the accessory factors marginally improved it. We proposed that the RecA-bound nucleotide (ATP and to a lesser extent dATP) might dictate the requirement for accessory factors.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available