Figure 3

Effects of temperature (a) and pH (b) on P-19486 alliinase. In (a), the optimum temperature (open circle) was determined by incubating the enzyme under the standard assay condition at each temperature. In the assay of thermal stability (closed circle), the enzyme activity was measured by the addition of (±)-alliin to the standard assay mixture, in which the enzyme had been preincubated at each temperature for 30 min. In (b), the optimum pH (open circle) was determined by incubating the enzyme under the standard assay condition where pH of the mixture was adjusted as indicated. In the assay of pH stability (closed circle), the enzyme activity was measured by the addition of (±)-alliin to the standard assay mixture, in which the enzyme had been preincubated at 4°C and at each pH for 30 min