Cytochalasin B-Induced ATPase Activity of Actin: Dependence on Monomer Concentration

Abstract
Polymerization and ATPase activity of [rabbit skeletal muscle] actin induced by cytochalasin B [CB] were studied simultaneously. Under all conditions tested, ATPase activity was proportional to the concentration of actin which was unpolymerized. Conditions increasing ATPase activity increase the velocity of polymerization. CB-induced ATPase activity apparently is a property of the actin monomers. The readiness of the monomers to hydrolyze ATP apparently is correlated with an increased capacity of the monomers to polymerize.