The effect of phosphoenolpyruvate, fructose 1,6-diphosphate and pH on allosteric pyruvate kinase in muscle tissue of the bivalve Mytilus edulis L

Abstract

1. 1.Pyruvate kinase (ATP:pyruvate phosphotransferase, EC 2.7.1.40) in muscle tissue of the sea mussel Mytilus edulis possesses properties which are similar to allosteric L-type pyruvate kinase of the rat liver with respect to stimulation by phosphoenolpyruvate and Fru-1,6-P2. The action of these modulators is pH dependent. In contrast to L-type there is an increasing stimulation by phosphoenolpyruvate and Fru-1,6-P2 by lowering the pH within the range from 8 to 6.

2. 2.A possible regulatory role of the pH influence on enzyme activity is discussed.