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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) ( approximately 10- and approximately 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 epsilon epistatic group (namely ruvA, recD, and recU). In the presence of Mg(2+), 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.

SUBMITTER: Ayora S

PROVIDER: S-EPMC327168 | biostudies-literature | 2004 Jan

REPOSITORIES: biostudies-literature

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Bacillus subtilis RecU protein cleaves Holliday junctions and anneals single-stranded DNA.

Ayora Silvia S Carrasco Begoña B Doncel-Perez Ernesto E Lurz Rudi R Alonso Juan C JC

Proceedings of the National Academy of Sciences of the United States of America 20031230 2

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) ( approximately 10- and approximately 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 observ ...[more]

PMID: 14701911

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