DNA gyrase subunit A

UniProtKB accession:  P9WG47

Grouped By:  Matching UniProtKB accession

UniProtKB description:  A type II topoisomerase that negatively supercoils closed circular double-stranded (ds) DNA in an ATP-dependent manner to maintain chromosomes in an underwound state, while in the absence of ATP it relaxes supercoiled dsDNA (PubMed:15047530, PubMed:16377674, PubMed:16876125, PubMed:17015625, PubMed:18426901, PubMed:19060136, PubMed:22844097, PubMed:20805881). Also catalyzes the interconversion of other topological isomers of dsDNA rings, including catenanes (PubMed:16876125, PubMed:19060136, PubMed:22457352). Gyrase from M.tuberculosis has higher decatenation than supercoiling activity compared to E.coli; as M.tuberculosis only has 1 type II topoisomerase, gyrase has to fulfill the decatenation function of topoisomerase IV as well (PubMed:16876125, PubMed:22457352, PubMed:23869946). At comparable concentrations M.tuberculosis gyrase cannot introduce as many negative supercoils into DNA as the E.coli enzyme, and its ATPase activity is lower, perhaps because it does not couple DNA wrapping and ATP binding as well as E.coli (PubMed:22457352).