1w36
From Proteopedia
RecBCD:DNA complex
Structural highlights
Function[EX5B_ECOLI] Required for efficient DNA repair; it catalyzes the unwinding of double-stranded DNA and the cleavage of single-stranded DNA and it stimulates local genetic recombination. All of these activities require concomitant hydrolysis of ATP. [EX5A_ECOLI] Exhibits several catalytic activities, including ATP-dependent exonuclease, ATP-stimulated endonuclease, ATP-dependent unwinding and DNA-dependent ATPase activities. Strand cleavage occurs 5' to 3' during the unwinding of duplex DNA at CHI sequences, which locally stimulate recombination. [EX5C_ECOLI] Exhibits a wide variety of catalytic activities including ATP-dependent exonuclease, ATP-stimulated endonuclease, ATP-dependent helicase and DNA-dependent ATPase activities. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedRecBCD is a multi-functional enzyme complex that processes DNA ends resulting from a double-strand break. RecBCD is a bipolar helicase that splits the duplex into its component strands and digests them until encountering a recombinational hotspot (Chi site). The nuclease activity is then attenuated and RecBCD loads RecA onto the 3' tail of the DNA. Here we present the crystal structure of RecBCD bound to a DNA substrate. In this initiation complex, the DNA duplex has been split across the RecC subunit to create a fork with the separated strands each heading towards different helicase motor subunits. The strands pass along tunnels within the complex, both emerging adjacent to the nuclease domain of RecB. Passage of the 3' tail through one of these tunnels provides a mechanism for the recognition of a Chi sequence by RecC within the context of double-stranded DNA. Gating of this tunnel suggests how nuclease activity might be regulated. Crystal structure of RecBCD enzyme reveals a machine for processing DNA breaks.,Singleton MR, Dillingham MS, Gaudier M, Kowalczykowski SC, Wigley DB Nature. 2004 Nov 11;432(7014):187-93. PMID:15538360[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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