title: Characterisation of cadmium-binding proteins from mussels, Mytilus edulis (L), exposed to cadmium.
abstract: Three Cd2+-binding proteins have been purified and partially characterised from the digestive gland of the bivalve mollusc, Mytilus edulis, after exposure to Cd2+. The major protein, which was judged to be pure on polyacrylamide gel electrophoresis, showed many of the characteristics of mammalian metallothionein; having a high -SH content, few aromatic amino acids and a high A250/A280 nm ratio which disappears on acidification. It also contains Zn and Cu, but differs in its higher apparent molecular weight of about 25 000 and high glycine content (12-19%). The two additional Cd2+-binding proteins had lower cysteine contents and different molar proportions of Cd2+, Zn2+ and Cu2+.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D049872:Bivalvia / Q000378:metabolism*; D002104:Cadmium / Q000378:metabolism*; D002352:Carrier Proteins / Q000302:isolation & purification*; D055598:Chemical Phenomena; D002621:Chemistry; D003300:Copper / Q000302:isolation & purification; D006736:Horses; D013057:Spectrum Analysis / Q000379:methods; D015032:Zinc / Q000302:isolation & purification
chemical_list: D000596:Amino Acids; D002352:Carrier Proteins; D002104:Cadmium; D003300:Copper; D015032:Zinc