Fish species that frequent the cold temperatures of the Arctic Ocean (e.g., toothfish, cod, ice fish, etc.) have special ‘antifreeze’ proteins within their blood stream that enables them not to freeze in the cold waters of the northern hemisphere. This discovery was made about 50 years ago.

Recently, scientists from the Ruhr-University Bochum in Germany discovered how these proteins work. In the presence of the proteins, water molecules in the blood stream act in a more uniform fashion and are more particular about the bonds that they create. Whereas without the antifreeze proteins, water molecules just create haphazard bonds. Now we understand why fish can survive in the temperatures of the polar oceans which are below what should freeze fish blood.

The scientists made this discovery by using a technique called terahertz radiation on an Antarctic toothfish, Dissostichus mawsoni.

Journal reference:
Simon Ebbinghaus, Konrad Meister, Benjamin Born, Arthur L. DeVries, Martin Gruebele, Martina Havenith. Antifreeze Glycoprotein Activity Correlates with Long-Range Protein−Water Dynamics. Journal of the American Chemical Society, 2010; : 100816142208022 DOI: 10.1021/ja1051632

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