Catenane higher order

The winding of DNA in higher-order forms such as knots and catenanes was also shown in electron micrographs of DNA molecules coated with Escherichia coli RecA protdn. It was found that DNA topoisomerase I of E. coli generates an equal mixture of (+) and (-) duplex DNA knots, and that one product was a catenane. It was later shown that RecQ helicase and topoisomerase III (Topo III) of E. coli together mediate a potent DNA strand passage activity that can catenate covalendy dosed DNA." The structure of the catenated DNA spedes formed by... 

It should be noted that in addition to interlocked structures consisting of two components, higher-order [n]-catenanes and [n]-rotaxanes and even polymeric interlocked structures may be constructed. However, this chapter will focus on the synergistic concepts behind the preparation and behavior of [2]-catenanes and [2]-rotaxanes that may be applied to larger systems. 

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