An atypical topoisomerase found in hyperthermophilic microorganisms, such as archaea and hyperthermophilic eubacteria. Reverse gyrase is able to positively supercoil DNA in the presence of ATP as helicases. In recent literature, it is classified as one of the Type I DNA topoisomerases (including topoisomerase I, III, V, and reverse gyrase). Previously, this enzyme was indexed under DNA Topoisomerase (ATP-Hydrolysing), a Type II DNA topoisomerase.
