Fagerburg MV, Schauer GD, Thickman KR, Bianco PR, Khan SA, Leuba SH, Anand SP. PcrA-mediated disruption of RecA nucleoprotein filaments--essential role of the ATPase activity of RecA.
Nucleic Acids Res 2012;
40:8416-24. [PMID:
22743269 PMCID:
PMC3458574 DOI:
10.1093/nar/gks641]
[Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The essential DNA helicase, PcrA, regulates recombination by displacing the recombinase RecA from the DNA. The nucleotide-bound state of RecA determines the stability of its nucleoprotein filaments. Using single-molecule fluorescence approaches, we demonstrate that RecA displacement by a translocating PcrA requires the ATPase activity of the recombinase. We also show that in a ‘head-on collision’ between a polymerizing RecA filament and a translocating PcrA, the RecA K72R ATPase mutant, but not wild-type RecA, arrests helicase translocation. Our findings demonstrate that translocation of PcrA is not sufficient to displace RecA from the DNA and assigns an essential role for the ATPase activity of RecA in helicase-mediated disruption of its filaments.
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