title: Structure of the response regulator VicR DNA-binding domain.
abstract: The response regulator VicR from the Gram-positive bacterium Enterococcus faecalis forms part of the two-component signal transduction system of the YycFG subfamily. The structure of the DNA-binding domain of VicR, VicR(c), has been solved and belongs to the winged helix-turn-helix family. It is very similar to the DNA-binding domains of Escherichia coli PhoB and OmpR, despite low sequence similarity, but differs in two important loops. The alpha-loop, which links the two helices of the helix-turn-helix motif, is similar to that of PhoB, where it has been implicated in contacting the sigma subunit of RNA polymerase, but differs from that of OmpR. Conversely, the loop following the helix-turn-helix motif is similar to that of OmpR and differs from that of PhoB. YycF/VicR, PhoB and Bacillus subtilis PhoP regulators all recognize almost identical DNA sequences and although there is currently no experimental evidence linking this loop with the DNA, the structure is consistent with possible involvement in selective DNA recognition or binding.
authors.affiliation: Astbury Centre for Structural Molecular Biology, Institute of Molecular and Cellular Biology, University of Leeds, Leeds LS2 9JT, England.
authors.forename: Chi-Hung
authors.initials: CH
authors.lastname: Trinh
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Simon E V
authors.initials: SE
authors.lastname: Phillips
authors.forename: Mary K
authors.initials: MK
authors.lastname: Phillips-Jones
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D001483:Base Sequence; D001665:Binding Sites; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry*; D013293:Enterococcus faecalis / Q000737:chemistry*; D018257:Helix-Loop-Helix Motifs
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C119939:YycF protein, Bacteria; D004247:DNA