Reaction: ATP-independent breakage of single-stranded DNA, followed by passage and rejoining
Other name(s): type I DNA topoisomerase; untwisting enzyme; relaxing enzyme; nicking-closing enzyme; swivelase; ω-protein; deoxyribonucleate topoisomerase; topoisomerase
Systematic name: DNA topoisomerase
Comments: These enzymes bring about the conversion of one topological isomer of DNA into another, e.g., the relaxation of superhelical turns in DNA, the interconversion of simple and knotted rings of single-stranded DNA, and the intertwisting of single-stranded rings of complementary sequences, cf. EC 18.104.22.168 DNA topoisomerase (ATP-hydrolysing).
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
1. Gellert, M. DNA topoisomerases. Annu. Rev. Biochem. 50 (1981) 879-910. [PMID: 6267993]