title: Reverse gyrase--a topoisomerase which introduces positive superhelical turns into DNA.
abstract: An enzymatic activity which converts closed circular DNA into a positively supercoiled form is present in cellular extracts of Sulfolobus, an acidothermophilic archaebacterium. This novel enzyme is a type II DNA topoisomerase and is active only at temperatures greater than 55 degrees C, in the presence of ATP and Mg2+.
mesh_terms: D004264:DNA Topoisomerases, Type I; D004250:DNA Topoisomerases, Type II / Q000378:metabolism*; D004278:DNA, Superhelical / Q000096:biosynthesis*; D006090:Gram-Negative Bacteria / Q000201:enzymology*; D006358:Hot Temperature; D007700:Kinetics; D010957:Plasmids
chemical_list: D004278:DNA, Superhelical; C041813:DNA reverse gyrase; D004264:DNA Topoisomerases, Type I; D004250:DNA Topoisomerases, Type II