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One of a group of molecules that have the same chemical formula but different topologic structures, particularly forms of DNA that have different numbers of twists or supercoils.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
The topics include the two-dimensional agarose gel electrophoresis of DNA topoisomers, single-molecule magnetic tweezer studies of type IB topoisomers, binding DNA topoisomers I and II to replication origins, assaying topoisomers II checkpoints in yeast, the cytological analysis of chromosome structural defects that result from topoisomers II dysfunction, and the depletion and mutation of topoisomerase II in animal cells.