Bacillus subtilis RecU protein cleaves Holliday junctions and anneals single-stranded DNA
Abstract
Bacillus subtilis RecU protein is involved in homologous recombination, DNA repair, and chromosome segregation. Purified RecU binds preferentially to three- and four-strand junctions when compared to single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) (≈10- and ≈40-fold lower efficiency, respectively). RecU cleaves mobile four-way junctions but fails to cleave a linear dsDNA with a putative cognate site, a finding consistent with a similar genetic defect observed for genes classified within the ε epistatic group (namely ruvA, recD, and recU). In the presence of Mg2+, RecU also anneals a circular ssDNA and a homologous linear dsDNA with a ssDNA tail and a linear ssDNA and a homologous supercoiled dsDNA substrate. These results suggest that RecU, which cleaves recombination intermediates with high specificity, might also help in their assembly.
- Publication:
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Proceedings of the National Academy of Science
- Pub Date:
- January 2004
- DOI:
- 10.1073/pnas.2533829100
- Bibcode:
- 2004PNAS..101..452A
- Keywords:
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- BIOCHEMISTRY