Using calcium pump ATPase, a calmodulin (CaM)-dependent and SH-group-indispensable enzyme as a model system, we found that Pb2+,Cdand Hg2+effectively substituted for Ca2+ to interact with CaM and stimulated the enzyme.

• 猪红细胞膜Ca~(2+)-ATP酶是一种钙调蛋白(CaM)依赖酶,其活力又依赖巯基的完整性。