topoisomerase


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Related to topoisomerase: DNA gyrase

topoisomerase

 [to″po-i´so-mer-ās]
an enzyme involved in mobilization and replication of DNA during cell division.

to·po·i·so·mer·ase

(tō'pō-i-som'ĕr-ās),
A type of enzyme converting (isomerizing) one topologic version of DNA into another; acts by catalyzing the breakage and reformation of DNA phosphodiester linkages.
[topo- + isomerase]

topoisomerase

(tō′pō-ī-sŏm′ə-rās′, -rāz′)
n.
Either of two isomerase enzymes that alter the topology of DNA molecules by breaking and reconnecting coiled strands.
References in periodicals archive ?
(The first topoisomerase inhibitors are given by injection, but a new one -- Orathecin, formerly named Rubitecan -- now waiting for FDA approval for pancreatic cancer, is taken orally.
Topoisomerases are already targets for several drugs including anti-tumour drugs and antibiotics, such as ciprofloxacin--the anti-anthrax drug.
DNA replication: topological aspects and the role of DNA topoisomerases. Cold spring harbor laboratory press, Manie USA, pp 321-340.
The topoisomerase II alpha gene product is a target of anthracyclines, and the gene is localised on chromosome 17q(21-22) in close proximity to HER2.
It is noteworthy that the mean score of each molecule was higher than 0.77 and it was indicated that all of them were potent anticancer agents that definitely were antineoplastics, topoisomerase I inhibitor and DNA intercatalor agents.
A mutation in yeast topoisomerase II that confers hypersensitivity to multiple classes of topoisomerase II poisons.
It has been given in multiple combinations with conventional chemotherapeutic agents, including alkylators, topoisomerase II inhibitors, topoisomerase I inhibitors, and microtubule inhibitors [34, 39, 42, 43].
Doxorubicin analogs that are less cardiotoxic (cause reduced in vivo chronic cardiotoxicity in rats and rabbits) are also less potent as poisons for topoisomerase 2[beta] (top2[beta]) and equally or more potent as poisons for topoisomerase 2a (top2[alpha]) compared to doxorubicin (DOX).
Resistance to quinolones and [beta]-lactams in Salmonella enterica due to mutations in topoisomerase encoding genes, altered cell permeability and expression of an active efflux system.