Inactivation of mevalonate 5-diphosphate decarboxylase by phosphorothioate analogues of ATP.

Mevalonate 5-diphosphate decarboxylase is inactivated by several nucleoside phosphorothioates and the order of effectiveness as inactivators is: (Rp) ATP beta S greater than (Sp) ATP beta S approximately equal to ADP beta S approximately equal to AMPS greater than ATP gamma S. Mevalonate 5-diphosphate protects the enzyme against inactivation and, to a lower extent, so does ATP. As dithiothreitol prevents the enzyme inactivation, these results are interpreted as being the consequence of the interaction of the above mentioned analogues with functional thiol groups of the enzyme.