Scientists isolate new antifreeze molecule in Alaska beetle

Via Institute of Arctic Biology

FAIRBANKS, Alaska-- -- Scientists have identified a novel antifreeze molecule in a freeze-tolerant Alaska beetle able to survive temperatures below minus 100 degrees Fahrenheit. Unlike all previously described biological antifreezes that contain protein, this new molecule, called xylomannan, has little or no protein. It is composed of a sugar and a fatty acid and may exist in new places within the cells of organisms.

"The most exciting part of this discovery is that this molecule is a whole new kind of antifreeze that may work in a different location of the cell and in a different way," said zoophysiologist Brian Barnes, director of the University of Alaska Fairbanks Institute of Arctic Biology and one of five scientists who participated in the Alaska Upis ceramboides beetle project.

Just as ice crystals form over ice cream left too long in a freezer, ice crystals in an insect or other organism can draw so much water out of the organism’s cells that those cells die. Antifreeze molecules function to keep small ice crystals small or to prevent ice crystals from forming at all. They may help freeze-tolerant organisms survive by preventing freezing from penetrating into cells, a lethal condition. Other insects use these molecules to resist freezing by supercooling when they lower their body temperature below the freezing point without becoming solid.

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