Figure 7.

Abortive TP–(dNMP)_n products accumulate for DNA polymerase mutants affected in TP binding. The assay was performed as described in Materials and Methods. Samples were analyzed by high resolution SDS–PAGE. The first left-most 10 nt of the Φ29 genome are depicted at the top. Samples contained 20 µM each [α-³²P]dATP (1 µCi), dGTP and dTTP. Whereas the first series of samples (a) was stopped after incubation at 30°C for 5 min, dCTP was added to the second series of samples (b) for an additional 5 min incubation at 30°C. The length of different transition products and the position corresponding to full-length Φ29 TP–DNA are indicated.