lmmol · Proteins

DNA gyrase subunit B

UniProt P0AES6 Organism Escherichia coli (strain K12) Gene JW5625, acrB, b3699, cou, gyrB, himB, hisU, nalC, parA, pcbA EC 5.6.2.2

Also known as: JW5625, acrB, b3699, cou, gyrB, himB, hisU, nalC, parA, pcbA

Function

DNA gyrase negatively supercoils closed circular double-stranded DNA in an ATP-dependent manner to maintain chromosomes in an underwound state. This makes better substrates for topoisomerase 4 (ParC and ParE) which is the main enzyme that unlinks newly replicated chromosomes in E.coli. Gyrase catalyzes the interconversion of other topological isomers of double-stranded DNA rings, including catenanes. Relaxes negatively supercoiled DNA in an ATP-independent manner. E.coli gyrase has higher supercoiling activity than other characterized bacterial gyrases; at comparable concentrations E.coli gyrase introduces more supercoils faster than M.tuberculosis gyrase, while M.tuberculosis gyrase has higher decatenation than supercoiling activity compared to E.coli. E.coli makes 15% more negative supercoils in pBR322 plasmid DNA than S.typhimurium; the S.typhimurium GyrB subunit is toxic in E.coli, while the E.coli copy can be expressed in S.typhimurium even though the 2 subunits have 777/804 residues identical. The enzymatic differences between E.coli gyrase and topoisomerase IV are largely due to the GyrA C-terminal domain (approximately residues 524-841) and specifically the GyrA-box.

Classification

Family (Pfam)
PF00204 DNA_gyraseB, PF00986 DNA_gyraseB_C, PF21249 GyrB_hook, PF18053 GyrB_insert, PF02518 HATPase_c, PF01751 Toprim
InterPro
DNA_gyrase_B_C, GyrB, GyrB_hook, GyrB_insert, HATPase_C_sf, HATPase_dom, Ribosomal_Su5_D2-typ_SF, Ribsml_uS5_D2-typ_fold_subgr, Topo_IIA, Topo_IIA-like_dom_sf, Topo_IIA_B, Topo_IIA_B_C, Topo_IIA_bsu_dom2, TopoIIA_CS, TOPRIM_dom, TOPRIM_GyrB
Functional cluster
S-Adenosylmethionine Synthases & related

Experimental structures · PDB · 71

A predicted model is available from AlphaFold.

Gene Ontology · 15

Drugs targeting this protein · 29

Related proteins · sequence + function similarity

Co-cited proteins · studied together in the literature

Literature · 46 cited papers

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