topoisomerases


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topoisomerases

Enzymes that assist in the topological manipulation of DNA. Before DNA can replicate it must be unwound. This occurs in short segments and is achieved by a Type I topoisomerase that cuts one strand so that the free end can be rotated around the unbroken strand. Topoisomerase 1 then re-ligates the broken strand. Type II topoisomerases cut both strands. The term is pronounced ‘topo-isomerase’. The derivation is Greek, topos , a place; iso , equal; meros , a part; with the -ase suffix denoting an enzyme.
References in periodicals archive ?
The remaining one strain, which possessed an amino acid alteration in the GrlB subunit of topoisomerase IV, had increased susceptibility to galangin.
DNA topoisomerases and their poisoning by anticancer and antibacterial drugs.
The critical involvement of DNA topoisomerases in various essential cellular processes has led to the development of topoisomerase poisons for use as antibacterial [192, 193] or anticancer therapeutics [194, 195].
Kasparkova et al., "Inhibition of DNA topoisomerases I and II and growth inhibition of HL-60 cells by novel acridine-based compounds," European Journal of Pharmaceutical Sciences, vol.
Background: To investigate the role of a topoisomerase I inhibitor (topotecan) in chemoresistant ovarian cancer-initiating cells.
This study could also explain why some people with mutations in topoisomerases develop autism and other neurodevelopmental disorders.
"Our study shows the magnitude of what can happen if topoisomerases are impaired," said senior study author Mark Zylka, PhD, associate professor in the Neuroscience Center and the Department of Cell Biology and Physiology at UNC.
Camptothecine (CPT), a quinoline alkaloid, is a potent inhibitor of eukaryotic topoisomerase I.
Previous studies (42) have demonstrated that changes in topoisomerases are insufficient to explain the level of resistance to quinolones in S.
Within human TCGA data, we found that topoisomerases are differentially expressed across the 4 GBM subtypes, with proneural subtype showing the highest levels of both TOP2a and TOP2b expressions.