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PcrA-mediated disruption of RecA nucleoprotein filaments--essential role of the ATPase activity of RecA.

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.

SUBMITTER: Fagerburg MV

PROVIDER: S-EPMC3458574 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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PcrA-mediated disruption of RecA nucleoprotein filaments--essential role of the ATPase activity of RecA.

Fagerburg Matt V MV Schauer Grant D GD Thickman Karen R KR Bianco Piero R PR Khan Saleem A SA Leuba Sanford H SH Anand Syam P SP

Nucleic acids research 20120628 17

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 ...[more]

PMID: 22743269

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