Isolation and properties of creatine kinase from the breast muscle of tropical fruit bat, Eidolon helvum (Kerr)

1. Creatine kinase, from fruit bat breast muscle, has been purified to homogeneity.2. The mol. wt of the enzyme was estimated to be about 78,000-80,000 with two subunits of 42,500.3. There are nine thiol residues/mol of the enzyme and two of these react readily with DTNB leading to total inactivation of the enzyme.4. The metal ion specificity was in order Mg2+ > Zn2+ > Co2+.5. Initial velocity and product inhibition studies of the reverse reaction are consistent with sequential reaction but of either rapid equilibrium random or ordered type.