Analysis of polyoma virus DNA replicative intermediates by agarose gel electrophoresis

Agarose gel electrophoresis has been used to fractionate polyoma virus DNA replicative intermediates (RI) according to maturity. Approximate electrophoretic mobility versus maturity relationships were obtained for both intact (supercoiled) and nicked (relaxed) RI. There was considerable overlap between the supercoiled and relaxed RI populations after electrophoretic fractionation. Intact RI could be recovered from preparative agarose gels for further analysis by centrifugation, electron microscopy, re-electrophoresis, or nuclease digestion.