Open AccessThe role of monovalent cations in the ATPase reaction of DNA gyrase
Author(s) -
Hearnshaw Stephen James,
Chung Terence TszHong,
Stevenson Clare Elizabeth Mary,
Maxwell Anthony,
Lawson David Mark
Publication year - 2015
Publication title -
acta crystallographica section d
Language(s) - English
Resource type - Journals
ISSN - 1399-0047
DOI - 10.1107/s1399004715002916
Subject(s) - dna gyrase , chemistry , crystallography , dna , atpase , binding site , protein subunit , domain (mathematical analysis) , function (biology) , crystal structure , escherichia coli , biophysics , stereochemistry , biochemistry , biology , enzyme , genetics , gene , mathematical analysis , mathematics
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.