A bacterial DNA topoisomerase II that catalyzes ATP-dependent breakage of both strands of DNA, passage of the unbroken strands through the breaks, and rejoining of the broken strands. Gyrase binds to DNA as a heterotetramer consisting of two A and two B subunits. In the presence of ATP, gyrase is able to convert the relaxed circular DNA duplex into a superhelix. In the absence of ATP, supercoiled DNA is relaxed by DNA gyrase.
Entry Term(s)
DNA Gyrase A Subunit
DNA Gyrase B Subunit
DNA-Gyrase
GyrA Protein
GyrB Protein
Previous Indexing
DNA, Circular (1976-1977)
DNA Topoisomerases (1977-1978)
DNA Topoisomerases, Type II (1979-2001)
Public MeSH Note
2002; see DNA TOPOISOMERASE (ATP-HYDROLYZING) 1994-2001, see DNA GYRASE 1980-1993; GYRA PROTEIN was indexed under DNA TOPOISOMERASE (ATP-HYDROLYZING) (NM) 1992-2001; GYRB PROTEIN was indexed under DNA TOPOISOMERASE (ATP-HYDROLYZING) (NM) 1991-2001
History Note
2002; use DNA TOPOISOMERASE (ATP-HYDROLYZING) 1994-2001, use DNA GYRASE 1980-1993; for GYRA PROTEIN use DNA TOPOISOMERASE (ATP-HYDROLYZING) (NM) 1992-2001; GYRB PROTEIN use DNA TOPOISOMERASE (ATP-HYDROLYZING) (NM) 1991-2001
A bacterial DNA topoisomerase II that catalyzes ATP-dependent breakage of both strands of DNA, passage of the unbroken strands through the breaks, and rejoining of the broken strands. Gyrase binds to DNA as a heterotetramer consisting of two A and two B subunits. In the presence of ATP, gyrase is able to convert the relaxed circular DNA duplex into a superhelix. In the absence of ATP, supercoiled DNA is relaxed by DNA gyrase.
