Apparent deficiency of metallothionein in the liver of the Antarctic icefish Chionodraco hamatus. Identification and isolation of a zinc-containing protein unlike metallothionein.

1. A zinc-binding protein has been isolated and purified from the liver of the icefish Chionodraco hamatus. 2. The icefish Zn-protein has characteristics distinct from those of metallothionein. 3. The amino acid composition shows a low content of cysteine and a high content of glutamate and aspartate. 4. No metallothionein has been detected in the extracts from icefish liver.