Reverse gyrase (IPR005736)

Short name: Reverse_gyrase

Overlapping homologous superfamilies


Family relationships


This entry represents reverse gyrases found in both bacteria and archaea. Reverse gyrase, a fusion of a type I topoisomerase domain and a helicase domain, introduces positive supercoiling to increase the melting temperature of DNA double strands. Generally, these gyrases are encoded as a single polypeptide. An exception was found in Methanopyrus kandleri, where enzyme is split within the topoisomerase domain, yielding a heterodimer of gene products designated RgyB and RgyA.

DNA topoisomerases are divided into two classes: type I enzymes (EC:; topoisomerases I, III and V) break single-strand DNA, and type II enzymes (EC:; topoisomerases II, IV and VI) break double-strand DNA [PMID: 12596227]. Type I topoisomerases can be subdivided according to their structure and reaction mechanisms: type IA (bacterial and archaeal topoisomerase I, topoisomerase III and reverse gyrase) and type IB (eukaryotic topoisomerase I and topoisomerase V). Most of the Type I topoisomerases are ATP-independent and are responsible for relaxing positively and/or negatively supercoiled DNA. Reverse gyrase is a unique type IA topoisomerase in that it requires ATP and can introduce positive supercoils into DNA.

GO terms

Biological Process

GO:0006265 DNA topological change

Molecular Function

GO:0003677 DNA binding
GO:0003916 DNA topoisomerase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.