Dissostichus mawsoni

Fig. 2. Disc electrophoretic patterns of blood sera (1) man (2) king salmon (3) rainbow trout (4) Trematomus borchgrevinki, and (5) Dissostichus mawsoni. For D. mawsoni the most acidic component is the albumin, the next two bands the transferrins, and the antifreeze glycoproteins appear between the origin and the first band when the gel is stained for carbohydrate. From Komatsu et al. (1970b), reproduced with permission.

Chemical Composition of Antifreeze Glycoproteins from Trematomus borchgrevinki and Dissostichus mawsoni ... 

There have been studies on at least one dozen species of fishes in McMurdo Sound. Those most studied by Antarctic investigators are Trematomus borchgrevinki, T. bernacchii, and Dissostichus mawsoni. The characteristics of the fish are discussed elsewhere (8,12). 

The glycosyltransferases used in these studies were all well characterised and were apparently pure in that each was an homogeneous enzyme protein. They are listed, with their sources, in Table 4.1. Artificial substrates for these enzymes were prepared from human transferrin and its asialo-derivative, and from the antifreeze glycoprotein of the serum of the arctic fish Dissostichus mawsoni. The structures of these substrates are given in Table 4.2. 

The amount of bound water (studied by H n.m.r. spectroscopy) and the extended molecular conformation appear to be responsible for the anti-freeze properties of a glycoprotein from the Antarctic fish Dissostichus mawsoni. Chemical modification has shown that the carbohydrate moiety of the glycoprotein component of the (Na + K )ATPase in membrane preparations of the salt glands from dog fish does not contribute to the catalytic activity of the enzyme. One of two glycoproteins extracted from squids (Sepia officinalis) resembles collagen. ... 

The levels of bound water and the extended conformation of a glycoprotein found in the Antarctic fish, Dissostichus mawsoni, are responsible for the antifreeze properties of the glycoprotein. ... 

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