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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.

SUBMITTER: Hearnshaw SJ

PROVIDER: S-EPMC4388272 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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The role of monovalent cations in the ATPase reaction of DNA gyrase.

Hearnshaw Stephen James SJ Chung Terence Tsz-Hong TT Stevenson Clare Elizabeth Mary CE Maxwell Anthony A Lawson David Mark DM

Acta crystallographica. Section D, Biological crystallography 20150327 Pt 4

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 th ...[more]

PMID: 25849408

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