Some Properties of Metallothioneins from Hepato-pancreas and Kidney in Carp (Cyprinus carpio)

抄録

Carp (Cyprinus carpio) were injected intraperitoneally with 2 mg Cd/kg body weight as CdCl₂ solution. Two types of isometallothioneins were separated from carp kidney by successive treatment with homogenization, ultracentrifugation, incubation, centrifugation, gel filtration and ion exchange chromatography. Purity was shown by polyacrylamide DISC-gel electrophoresis. The molecular weight of native metallothionein-I and -II was found to be 12000-13000. The disappearance of Cd-mercaptide bond was estimated under acidic conditions. Cysteic residues were about 30% in kidney isometallothioneins, Gly and Lys were high, but no aromatic amino acids or His residues were detected. In a double diffusion test, spur formation was shown between two hepato-pancreatic isometallothioneins, and also between hepato-pancreatic metallothionein-II and kidney metallothionein-II.