title: The role of monovalent cations in the ATPase reaction of DNA gyrase.
abstract: Four new crystal structures of the ATPase domain of the GyrB subunit of Escherichia coli DNA gyrase have been determined. One of these, solved in the presence of K(+), is the highest resolution structure reported so far for this domain and, in conjunction with the three other structures, reveals new insights into the function of this domain. Evidence is provided for the existence of two monovalent cation-binding sites: site 1, which preferentially binds a K(+) ion that interacts directly with the α-phosphate of ATP, and site 2, which preferentially binds an Na(+) ion and the functional significance of which is not clear. The crystallographic data are corroborated by ATPase data, and the structures are compared with those of homologues to investigate the broader conservation of these sites.
authors: Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, England.
authors: Stephen James
authors: SJ
authors: Hearnshaw
authors: Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, England.
authors: Terence Tsz-Hong
authors: TT
authors: Chung
authors: Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, England.
authors: Clare Elizabeth Mary
authors: CE
authors: Stevenson
authors: Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, England.
authors: Anthony
authors: A
authors: Maxwell
authors: Department of Biological Chemistry, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, England.
authors: David Mark
authors: DM
authors: Lawson
mesh_terms: D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D001665:Binding Sites; D002414:Cations, Monovalent / Q000378:metabolism; D018360:Crystallography, X-Ray; D027081:DNA Gyrase / Q000737:chemistry* / Q000378:metabolism; D004926:Escherichia coli / Q000737:chemistry / Q000201:enzymology* / Q000378:metabolism; D008958:Models, Molecular; D011188:Potassium / Q000378:metabolism; D011487:Protein Conformation; D012964:Sodium / Q000378:metabolism
chemical_list: D002414:Cations, Monovalent; D000255:Adenosine Triphosphate; D012964:Sodium; D000251:Adenosine Triphosphatases; D027081:DNA Gyrase; D011188:Potassium
keywords: ATPase activity; ATPase domain; DNA gyrase; GHKL superfamily; monovalent cations