Physiological and chemical characterization of invertebrate metallothionein-like proteins

Metallothionein-like proteins have been isolated from marine invertebrates. Three crustaceans, Scyllus serratus, Cancer magister and Acetes sibogae together with a mollusc, Cryptochiton stelleri, have been investigated. S. serratus hepatopancreas was shown to contain cadmium and zinc inducible metallothionein-like proteins with an amino acid analysis very similar to vertebrate metallothioneins. The molecular weight, ultra-violet spectrum and isoelectric points of S. serratus metallothioneins are also comparable to the vertebrate proteins, suggesting a fundamental biological function conserved throughout evolution.