Evidence of Phosphorylase Activity in Stylonychia Pustulata

Abstract

Qualitative and quantitative procedures were used to demonstrate phosphorylase activity i11 Slylonychia pz~sllrlata. The enzyme did not require divalent metal cations for activity; however, Mn2+, Ca2+, Co2+, and Zn?+ enhanced the activity. The enzyme was inhibited by Sr2+, Ba2+, Ni2+, Cd2+, Fez+, Sn2+, Hg2+, PIP, and Cu2+. The most elfective inhibitor was Sr2+, which produced about 57y0 inhibition. The enzyme was Inore active a t a pH of 6.2 than a t a pH of 7.2, 8.2, or 9.2. The optimum temperature for activity was about 30". The homogenates of the animals were found to contain 0 053 pg of glycogen/pg of protein N.The intracellular distribution of the enzyme in the animals could not be determined by the histochemical techniq~~es used in these experiments.