1bdx
From Proteopedia
E. COLI DNA HELICASE RUVA WITH BOUND DNA HOLLIDAY JUNCTION, ALPHA CARBONS AND PHOSPHATE ATOMS ONLY
Structural highlights
FunctionRUVA_ECOLI The RuvA-RuvB complex in the presence of ATP renatures cruciform structure in supercoiled DNA with palindromic sequence, indicating that it may promote strand exchange reactions in homologous recombination. RuvAB is a helicase that mediates the Holliday junction migration by localized denaturation and reannealing. RuvA stimulates, in the presence of DNA, the weak ATPase activity of RuvB. Binds both single- and double-stranded DNA (dsDNA). Binds preferentially to supercoiled rather than to relaxed dsDNA.[1] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedHere we present the crystal structure of the Escherichia coli protein RuvA bound to a key DNA intermediate in recombination, the Holliday junction. The structure, solved by isomorphous replacement and density modification at 6 A resolution, reveals the molecular architecture at the heart of the branch migration and resolution reactions required to process Holliday intermediates into recombinant DNA molecules. It also reveals directly for the first time the structure of the Holliday junction. A single RuvA tetramer is bound to one face of a junction whose four DNA duplex arms are arranged in an open and essentially four-fold symmetric conformation. Protein-DNA contacts are mediated by two copies of a helix-hairpin-helix motif per RuvA subunit that contact the phosphate backbone in a very similar manner. The open structure of the junction stabilized by RuvA binding exposes a DNA surface that could be bound by the RuvC endonuclease to promote resolution. Crystal structure of E.coli RuvA with bound DNA Holliday junction at 6 A resolution.,Hargreaves D, Rice DW, Sedelnikova SE, Artymiuk PJ, Lloyd RG, Rafferty JB Nat Struct Biol. 1998 Jun;5(6):441-6. PMID:9628481[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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