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. 1972 Feb;126(3):491–498. doi: 10.1042/bj1260491

Separation of two forms of rabbit metallothionein by isoelectric focusing

Gunnar F Nordberg 1, Monica Nordberg 1, Magnus Piscator 1, Olof Vesterberg 1,*
PMCID: PMC1178404  PMID: 5075263

Abstract

Rabbits were given repeated injections of cadmium chloride. Cadmium- and zinc-containing protein fractions were obtained from the livers of these animals by precipitation procedures and Sephadex G-75 chromatography. The protein thus obtained showed several characteristics similar to those of the earlier described protein metallothionein. Further separation by isoelectric focusing showed two main protein peaks with isoelectric points at 3.9 and 4.5 respectively. Amino acid analysis of these two forms showed similar content of most amino acids [residues per cent.: cysteine (28%), aspartate (8%), threonine (5–6%), serine (12%), glycine (7%), alanine (13%), methionine (2%), isoleucine (2%)] but with a small difference in content of lysine (12 and 13% respectively), proline (9 and 5% respectively) and glutamate (2 and 4% respectively). The two forms of the protein both contained cadmium, but only the one with pI4.5 contained also significant amounts of zinc.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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