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RecA dimers serve as a functional unit for assembly of active nucleoprotein filaments.

ABSTRACT: All RecA-like recombinase enzymes catalyze DNA strand exchange as elongated filaments on DNA. Despite numerous biochemical and structural studies of RecA and the related Rad51 and RadA proteins, the unit oligomer(s) responsible for nucleoprotein filament assembly and coordinated filament activity remains undefined. We have created a RecA fused dimer protein and show that it maintains in vivo DNA repair and LexA co-protease activities, as well as in vitro ATPase and DNA strand exchange activities. Our results support the idea that dimeric RecA is an important functional unit both for assembly of nucleoprotein filaments and for their coordinated activity during the catalysis of homologous recombination.

SUBMITTER: Forget AL

PROVIDER: S-EPMC2522307 | biostudies-literature | 2006 Nov

REPOSITORIES: biostudies-literature

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RecA dimers serve as a functional unit for assembly of active nucleoprotein filaments.

Forget Anthony L AL Kudron Michelle M MM McGrew Dharia A DA Calmann Melissa A MA Schiffer Celia A CA Knight Kendall L KL

Biochemistry 20061101 45

All RecA-like recombinase enzymes catalyze DNA strand exchange as elongated filaments on DNA. Despite numerous biochemical and structural studies of RecA and the related Rad51 and RadA proteins, the unit oligomer(s) responsible for nucleoprotein filament assembly and coordinated filament activity remains undefined. We have created a RecA fused dimer protein and show that it maintains in vivo DNA repair and LexA co-protease activities, as well as in vitro ATPase and DNA strand exchange activities ...[more]

PMID: 17087507

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