Cadmium-induced metallothioneins from the common sea mussel, Mytilus edulis, were shown to comprise of two groups of isoforms having apparent molecular masses of 10 kDa and 20 kDa. The 10-kDa group was resolved by anion-exchange chromatography into four fractions while the 20-kDa group was resolved into three fractions using this method. After metal removal and S-methylation of the cysteine residues using methyl-p-nitrobenzenesulphonate the complete amino acid sequences were determined. Five isoforms of the 20-kDa group were shown to possess monomeric units consisting of 71 amino acids. These proteins were distinct from the four 72-amino-acid proteins of the 10-kDa group. The FASTA algorithm has been used to compare the degree of similarity between the mussel metallothionein MT-10-IV isoform and other metallothioneins. The mussel MT-10-IV isoform exhibited substantial similarity to other molluscan metallothioneins. Moreover, the mussel metallothionein exhibited more similarity to vertebrate metallothioneins than to those of non-molluscan invertebrates, thus suggesting that the mussel metallothioneins are class I metallothioneins.
|Number of pages||12|
|Journal||EUR J BIOCHEM|
|Publication status||Published - 1993|
- Biochemistry & Molecular Biology
- GROWTH INHIBITORY FACTOR
- CDNA SEQUENCES
- MOLLUSCAN METALLOTHIONEINS
- RAT-LIVER METALLOTHIONEIN-2
MacKay, EA., Overnell, J., Dunbar, B., Davidson, I. R., Hunziker, P. E., Kagi, J. H. R., & Fothergill, J. E. (1993). COMPLETE AMINO-ACID-SEQUENCES OF 5 DIMERIC AND 4 MONOMERIC FORMS OF METALLOTHIONEIN FROM THE EDIBLE MUSSEL MYTILUS-EDULIS. EUR J BIOCHEM, 218(1), 183-194.