Why might the supercoiled versions of an uncut DNA plasmid move more slowly in an agarose gel than the linear version of the same plasmid?

The leading band (presumably representing supercoiled plasmid DNA) of a 5991bp plasmid containing 3600bp of the lac operon inserted into pBlueScript migrates at a rate approximately equivalent to...

16 December 2014 9,907 3 View