FIGURE 4.

Gel electrophoresis of AguA1 and AguA2 expressed in E. coli and enzymatic characterization of AguA1. A, SDS-PAGE analysis of the recombinant AguA1 and AguA2 proteins. Lane M, molecular mass standards; lane 1, supernatant of E. coli harboring pET30a; lanes 2 and 3, purification of AguA1 and AguA2, respectively. B, time course analysis of AguA1 and AguA2 activity with 10 mm agmatine. C, effect of pH on AguA1 activity. D, effect of temperature on AguA1 activity. E, Michaelis-Menten plot of AguA1 determined by measuring the enzymatic velocity. F, substrate specificity and competitive assay of AguA1 in the presence of 10 mm of agmatine and varying concentration (0–10 mm) of arginine. ND, not detectable.