Tdoay there was an interesting article in Chemistry World on antifreeze proteins called "Survival in the freezer", by James Mitchell Crow (unfortunately, it doesn't seem to be online yet, but I'm sure it will be shortly). The first of these was discovered by Arthur DeVries in 1969 (it was a glycoprotein), and the first carbohydrate-free one was discovered by his student John Duman in 1974. Both were found in fish that live in the Arctic, but antifreeze proteins are also present in other species, like Alaskan beetles. In fact, there's a great variety of antifreeze proteins, which probably evolved separately.
How do these proteins work? It seems that most have a flattish, slightly hydrophobic face with a regular repeating pattern. This surface seems to organize the waters immediately adjacent to it into ice-like structures, and so the protein binds nascent ice crystals, arresting their growth. One interesting application to antifreeze proteins in industry is to make low-fat ice cream (Unilever): by reducing the size of the ice crystals, less fat is required to make the ice cream equally creamy. Another potential application (not yet out) is to genetically modify salmon to make them produce antifreeze proteins, so that their growing season is a bit longer.
Finally, there are some other interesting compounds being made with antifreeze properties. A concrete example, from Matthew Gibson's group at Warwick, is polyvinyl alcohol (PVA), which seems to work very well although they don't really know why. The polymer doesn't seem to bind ice crystals, but they suggest it associates with the liquid-like "premelting" layer of water on the surface of ice.
Who knows? In any case, antifreeze proteins and their relationship to the surrounding water and ice might be a nice field to get into.
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