Ethylenediamine-NN'-tetra-acetate-dependent amino acid-stimulated inactivation of mouse ovarian alkaline phosphatase activity.

1. Preincubation of partially purified preparations of mouse ovarian alkaline phosphatase in the presence of both EDTA and glycine at alkaline pH resulted in a pronounced inactivation of alkaline phosphatase activity. Inactivation did not occur on preincubation with EDTA or glycine alone. 2. The rate of inactivation was first-order with respect to the concentration of enzyme, and was independent of EDTA concentration above a threshold value. 3. The process was pH-dependent with a pK at 9.85, and inactivation was not dependent on the stereochemistry of the amino acid. A free alpha-amino group and a free carboxyl group at a specific spatial separation were essential for inactivation. 4. Inactivation involved the formation of an enzyme--metal ion--amino acid complex, the amount formed being dependent on both the nature and concentration of the amino acid. This complex then decayed to a derivative that was then acted on by EDTA, yielding an inactive form of the enzyme.