L-Phenylalanine induced changes of sulfhydryl reactivity in rabbit muscle pyruvate kinase

Reactivity of sulfhydryl groups in rabbit muscle pyruvate kinase toward 5,5'-dithiobis (2-nitrobenzoic acid) (DTNB) was studied in the presence of activating divalent metal ions, substrate, substrate analogue, and the allosteric inhibitor, L-Phe. The pattern of sulfhydryl modification in various complexes of pyruvate kinase was consistent with the extent of enzyme inactivation by DTNB under very similar conditions. The sulfhydryl reactivity of …