title: A domain of RecC required for assembly of the regulatory RecD subunit into the Escherichia coli RecBCD holoenzyme.
abstract: The heterotrimeric RecBCD enzyme of Escherichia coli is required for the major pathway of double-strand DNA break repair and genetic exchange. Assembled as a heterotrimer, the enzyme has potent nuclease and helicase activity. Analysis of recC nonsense and deletion mutations revealed that the C terminus of RecC is required for assembly of the RecD subunit into RecBCD holoenzyme but not for recombination proficiency; the phenotype of these mutations mimics that of recD deletion mutations. Partial proteolysis of purified RecC polypeptide yielded a C-terminal fragment that corresponds to the RecD-interaction domain. RecD is essential for nuclease activity, regulation by the recombination hotspot Chi, and high affinity for DNA ends. The RecC-RecD interface thus appears critical for the regulation of RecBCD enzyme via the assembly and, we propose, disassembly or conformational change of the RecD subunit.
authors.affiliation: Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA.
authors.forename: Susan K
authors.initials: SK
authors.lastname: Amundsen
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Taylor
authors.forename: Gerald R
authors.initials: GR
authors.lastname: Smith
mesh_terms: D004269:DNA, Bacterial / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D029968:Escherichia coli Proteins / Q000378:metabolism; D043211:Exodeoxyribonuclease V; D005090:Exodeoxyribonucleases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020035:Holoenzymes / Q000737:chemistry / Q000378:metabolism; D009154:Mutation; D020836:Protein Structure, Quaternary; D017434:Protein Structure, Tertiary; D011938:Rec A Recombinases / Q000378:metabolism; D017384:Sequence Deletion
chemical_list: D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D020035:Holoenzymes; D011938:Rec A Recombinases; D005090:Exodeoxyribonucleases; D043211:Exodeoxyribonuclease V; C468322:exodeoxyribonuclease V, E coli