6.2
6.6
96% of maximal activity at pH 6.2 and 6.6
9.5
-
about 10-15% of maximum activity; about 10-15% of maximum activity
5.5
9
about 80% of maximal activity at pH 5.5 and about half-maximal activity at pH 9.0, sucrose cleavage
5
8.2
about 90% of maximal activity at pH 5.0 and about half-maximal activity at pH 8.2, sucrose cleavage
5
10
about half-maximal activity at pH 5.0 and 10.0, sucrose synthesis
5
8
about half-maximal activity at pH 5.0 and 8.0, sucrose cleavage
5.6
10
about half-maximal activity at pH 5.6 and about 90% of maximal activity at pH 10.0, sucrose synthesis
7.5
10
about half-maximal activity at pH 7.5 and about 90% of maximal activity at pH 10.0, sucrose synthesis
5.5
7.5
over 40% of maximal enzyme activity within this range
7
9
sucrose cleavage, activities with CDP, GDP, TDP, and UDP only occur at pH 7.0-8.0 and are very low at pH 9.0, while the activity with ADP is highest at pH 8.0 and higher than 60% of maximal activity in the pH range of 7.0-9.0