Structures of topoisomerase V in complex with DNA reveal unusual DNA-binding mode and novel relaxation mechanism.

ABSTRACT: Topoisomerase V is a unique topoisomerase that combines DNA repair and topoisomerase activities. The enzyme has an unusual arrangement, with a small topoisomerase domain followed by 12 tandem (HhH)₂ domains, which include 3 AP lyase repair domains. The uncommon architecture of this enzyme bears no resemblance to any other known topoisomerase. Here, we present structures of topoisomerase V in complex with DNA. The structures show that the (HhH)₂ domains wrap around the DNA and in this manner appear to act as a processivity factor. There is a conformational change in the protein to expose the topoisomerase active site. The DNA bends sharply to enter the active site, which melts the DNA and probably facilitates relaxation. The structures show a DNA-binding mode not obser

SUBMITTER: Osterman A 

PROVIDER: S-EPMC9489208 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature