Freezing resistance in Antarctic and Arctic fishes: its relation to mode of life, ecology and evolution ...

• Main Author: Woehrmann, Andreas
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Société Française d'Ichtyologie 1997
• Subjects: Activity, AFGP, Antarctic Ocean, Antifreeze, Arctic Ocean, Evolution, Gadiformes, Metabolism, Mode of life, Notothenioidei, PN, PS; Arctic; Antarctic; The Antarctic; Arctic Ocean; Antarctic Ocean; Antarc*
• Online Access: https://dx.doi.org/10.26028/cybium/1997-214-010; https://sfi-cybium.fr/fr/freezing-resistance-antarctic-and-arctic-fishes-its-relation-mode-life-ecology-and-evolution

Biological antifreezes are present in most Antarctic and Arctic fishes and lower the freezing point of most of their body fluids below the freezing point of seawater ( 1.9°C), without substantially increasing their osmotic pressure. In the blood of Antarctic notothenioid and Arctic gadiform fishes, freezing is inhibited by antifreeze glycopeptides (AFGP). These anti¬freeze molecules are built up of repeating tripeptide units (Ala-Ala-Thr)n, to which the disaccharide β-D-galactosyl-(1->3)α-N-acetyl-D-galactosamine is linked through the hydroxyl oxygen of the threonyl residue. Species of Liparididae, Zoarcidae, Cottidae and Pleuronectidae in the Antarctic, Arctic and northern-boreal waters synthesize only unglycosylated antifreeze peptides (AFP). The level of antifreeze concentration was dependent on the ambient water temperature, the depth of distribution, the life history and the level of activity of the species. Whereas the synthesis of AFGP in Antarctic and Arctic fish species appear to regulate by the ...