topological isomers of DNA
topological isomers of DNADNA molecules that are identical except for the number of times one strand of the double helix crosses over the other in a given length. Any change in this number (the linking number) requires that at least one strand must be broken. This process to change the linking number is catalysed by a TOPOISOMERASE.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005