Figure 3.

Catalytic activity of the 10-28 N-glycosylase. (A) Autoradiogram depicting the time course of the self-cleavage reaction, employing internally ³²P-labeled DNA under standard reaction conditions (see Materials and Methods). Reaction products were treated with piperidine before electrophoresis in a 5% denaturing polyacrylamide gel. Unclv, the 128-nucleotide starting DNA; and clv, the 111-nucleotide 3′ product. The 5′ product is unlabeled because it was contained within the DNA primer. (B) pH dependence of the reaction carried out in the presence of 2 mM Ca²⁺ and either 10 mM NaOAc (●) or 10 mM Mes (○).