Effects of alanine and conservative substitutions on 3′-phosphatase activity. 3′-Phosphatase activity was determined as a function of input protein for wild-type Pnk, D165A, D65N, D65E, D167A, D167N and D167E (A), R176A, R176K, R279A and R279K (B), wild-type Pnk, D254A, D254N, D254E, D278A, D278N and D278E (C) and R213A, R213K, R246A and R246K (D).