Figure 3.

Alkaline gel analysis of XhoI-digested kDNA from samples taken from a synchronous culture at 30 min intervals during S phase. Duplicate samples were run on the same gel and transferred to a membrane that was cut into three parts for hybridization separately to probes for minicircle L and H strands and for molecular weight markers. Fragment pairs reflecting discontinuities at oriA or oriB are indicated in brackets. Minor H-strand fragments corresponding to molecular sizes of ∼1.0 and 0.65 kb are indicated by triangles. A ladder of catenated minicircles is indicated by a bracket in the upperpart of the gel. dcc, denatured covalently closed minicircles.