effect of pyridoxal - 5 - phoaphate on the activity of myokinase enzyme

Pyridoxal-5-phosphate [PLP] inhibits platelet aggregation. It was suggested that PLP may exert its inhibitory effect by binding to ADP receptors. An ADP binding site in another system was considered to provide an analogy from which deductions may be made in regard to ADP binding sites on the platelet surface. The enzyme myokinase was believed to provide a suitably analogous ADP binding site. It has been shown that PLP did not inhibit the activity of myokinase from which it was inferred that PLP is unlikely to exert its inhibitory activity on platelet aggregation by binding to ADP receptor on the platelet surface