Fig. 3. Mapping of σ-like mp1 intermediates with two tails (double RCs). (A) Plasmid DNA from fractions 5 and 6 was combined and linearized with BglI, PvuI and SmaI, respectively. EM of 150 molecules in each digest revealed various double Ys. The location of the origins dso1 and dso2 was mapped. Examples are shown in the right panel. (B) Uncut double RCs initiated at dso1 and dso2 are explained in the model. Bar = 0.5 kb.