Binding of ATP to nucleoside‐diphosphate kinase: a kinetic study

Abstract
The binding of nucleotides to pig heart nucleoside‐diphosphate kinase was studied using Rose Bengal as an optical probe. ATP, in the absence of Mg2+, binds slowly to the enzyme, with a second order rate constant of about 3000 M−1·s−1, whereas in its presence the binding is much faster. This finding suggests the regulation of the nucleoside‐diphosphate kinase activity by uncomplexed ATP, and that ATP binds normally to the enzyme via a metal ion bridge.