New publication by the Colloms and Starks Groups
Topoisomerases relieve torsional stress in DNA that results from transcription and replication and disentangle newly replicated sister chromosomes. Toposomerases are essential in all living cells and are important anti-cancer and antimicrobial targets. Topoisomerases are normally assayed using kinetoplast DNA (kDNA) from Trypanosomes. This kDNA forms large chain-mail like networks of thousands of interlinked DNA minicircles that can be unlinked by topoisomerases. Work from Tony Maxwell’s group at the John Innes Centre in Norwich, in collaboration with Marshall Stark and Sean Colloms, has just been published in Biotechniques. This work shows that singly linked catenanes (two circles linked like the rings of a chain) made using Tn3 resolvase are much better substrates for topoisomerases than kDNA and can be used to measure accurately the effects of antibiotics such as ciprofloxacin and anti-cancer drugs such as etoposide on their cellular targets.
First published: 30 November 2020