UniProt functional annotation for P0A0K8



	UniProt functional annotation for P0A0K8

UniProt code: P0A0K8.

Organism: Staphylococcus aureus.

Taxonomy: Bacteria; Firmicutes; Bacilli; Bacillales; Staphylococcaceae; Staphylococcus.

Function: A type II topoisomerase that negatively supercoils closed circular double-stranded (ds) DNA in an ATP-dependent manner to modulate DNA topology and maintain chromosomes in an underwound state. Negative supercoiling favors strand separation, and DNA replication, transcription, recombination and repair, all of which involve strand separation. Also able to catalyze the interconversion of other topological isomers of dsDNA rings, including catenanes and knotted rings. Type II topoisomerases break and join 2 DNA strands simultaneously in an ATP-dependent manner. {ECO:0000255|HAMAP- Rule:MF_01898}.

Catalytic activity: Reaction=ATP-dependent breakage, passage and rejoining of double- stranded DNA.; EC=5.6.2.2; Evidence={ECO:0000255|HAMAP- Rule:MF_01898};

Cofactor: Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000255|HAMAP-Rule:MF_01898}; Name=Mn(2+); Xref=ChEBI:CHEBI:29035; Evidence={ECO:0000255|HAMAP-Rule:MF_01898}; Name=Ca(2+); Xref=ChEBI:CHEBI:29108; Evidence={ECO:0000255|HAMAP-Rule:MF_01898}; Note=Binds two Mg(2+) per subunit. The magnesium ions form salt bridges with both the protein and the DNA. Can also accept other divalent metal cations, such as Mn(2+) or Ca(2+). {ECO:0000255|HAMAP-Rule:MF_01898};

Activity regulation: Pyrazolthiazoles inhibit the ATPase activity of GyrB (PubMed:20356737). {ECO:0000269|PubMed:20356737}.

Subunit: Heterotetramer, composed of two GyrA and two GyrB chains. In the heterotetramer, GyrA contains the active site tyrosine that forms a transient covalent intermediate with DNA, while GyrB binds cofactors and catalyzes ATP hydrolysis. {ECO:0000255|HAMAP-Rule:MF_01898}.

Subcellular location: Cytoplasm {ECO:0000255|HAMAP-Rule:MF_01898}.

Miscellaneous: Few gyrases are as efficient as E.coli at forming negative supercoils. Not all organisms have 2 type II topoisomerases; in organisms with a single type II topoisomerase this enzyme also has to decatenate newly replicated chromosomes. {ECO:0000255|HAMAP- Rule:MF_01898}.

Similarity: Belongs to the type II topoisomerase GyrB family. {ECO:0000255|HAMAP-Rule:MF_01898}.

Annotations taken from UniProtKB at the EBI.


Organism:		Staphylococcus aureus.
Taxonomy:		Bacteria; Firmicutes; Bacilli; Bacillales; Staphylococcaceae; Staphylococcus.



Function:		A type II topoisomerase that negatively supercoils closed circular double-stranded (ds) DNA in an ATP-dependent manner to modulate DNA topology and maintain chromosomes in an underwound state. Negative supercoiling favors strand separation, and DNA replication, transcription, recombination and repair, all of which involve strand separation. Also able to catalyze the interconversion of other topological isomers of dsDNA rings, including catenanes and knotted rings. Type II topoisomerases break and join 2 DNA strands simultaneously in an ATP-dependent manner. {ECO:0000255\|HAMAP- Rule:MF_01898}.


Catalytic activity:		Reaction=ATP-dependent breakage, passage and rejoining of double- stranded DNA.; EC=5.6.2.2; Evidence={ECO:0000255\|HAMAP- Rule:MF_01898};
Cofactor:		Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000255\|HAMAP-Rule:MF_01898}; Name=Mn(2+); Xref=ChEBI:CHEBI:29035; Evidence={ECO:0000255\|HAMAP-Rule:MF_01898}; Name=Ca(2+); Xref=ChEBI:CHEBI:29108; Evidence={ECO:0000255\|HAMAP-Rule:MF_01898}; Note=Binds two Mg(2+) per subunit. The magnesium ions form salt bridges with both the protein and the DNA. Can also accept other divalent metal cations, such as Mn(2+) or Ca(2+). {ECO:0000255\|HAMAP-Rule:MF_01898};
Activity regulation:		Pyrazolthiazoles inhibit the ATPase activity of GyrB (PubMed:20356737). {ECO:0000269\|PubMed:20356737}.
Subunit:		Heterotetramer, composed of two GyrA and two GyrB chains. In the heterotetramer, GyrA contains the active site tyrosine that forms a transient covalent intermediate with DNA, while GyrB binds cofactors and catalyzes ATP hydrolysis. {ECO:0000255\|HAMAP-Rule:MF_01898}.
Subcellular location:		Cytoplasm {ECO:0000255\|HAMAP-Rule:MF_01898}.
Miscellaneous:		Few gyrases are as efficient as E.coli at forming negative supercoils. Not all organisms have 2 type II topoisomerases; in organisms with a single type II topoisomerase this enzyme also has to decatenate newly replicated chromosomes. {ECO:0000255\|HAMAP- Rule:MF_01898}.
Similarity:		Belongs to the type II topoisomerase GyrB family. {ECO:0000255\|HAMAP-Rule:MF_01898}.