RT Journal Article
SR Electronic
T1 Structures of topoisomerase V in complex with DNA reveal unusual DNA binding mode and novel relaxation mechanism
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.08.20.457074
DO 10.1101/2021.08.20.457074
A1 Amy Osterman
A1 Alfonso Mondragon
YR 2021
UL http://biorxiv.org/content/early/2021/08/20/2021.08.20.457074.abstract
AB 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 three AP lyase repair domains. The unusual 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 observed before and provide information on the way this unusual topoisomerase relaxes DNA.Competing Interest StatementThe authors have declared no competing interest.