Bi. Kurganov et al., KINETICS OF DISSOCIATION OF INACTIVE TETRAMERS OF MUSCLE GLYCOGEN-PHOSPHORYLASE-B INTO ACTIVE DIMERS, Biochemistry, 61(5), 1996, pp. 657-661
Recovery of the enzymatic activity of rabbit skeletal muscle glycogen
phosphorylase b preincubated with 1 mM AMP and 0.125 M K2SO4 (0.05 M g
lycylglycine buffer, pH 6.8; 17 degrees C) has been studied. According
to sedimentation data the preincubation conditions favor the formatio
n of the tetrameric form of the enzyme. When registering the kinetics
of the enzymatic reaction catalyzed by phosphorylase b preincubated wi
th AMP and K2SO4, an acceleration of the reaction during the course of
the enzymatic process was observed. On the basis of the kinetic data
the rate constant for dissociation of phosphorylase b tetramers into d
imers has been calculated: k=(8.3+/-0.3) 10(-3) sec(-1) (0.05 M glycyl
glycine buffer, pH 6.8; 17 degrees C).