Researchers have discovered a new class of biological antifreeze molecules: the first that do not contain proteins. The antifreeze, extracted from a freeze-tolerant Alaskan beetle, is made of a combination of sugars and fatty acids.
Dr. Kent Walters (University of Notre Dame) and colleagues report in the Nov. 24 issue of Proceedings of the National Academy of Sciences (PNAS) the successful isolation of a freeze-tolerant Alaskan beetle's anti-freeze molecule. The beetle from which the antifreeze was extracted is capable of surviving at -60°C (-76 F).
This discovery, which was funded by the National Science Foundation (NSF), could assist future efforts at preserving cells or whole tissues by cooling them to low sub-zero temperatures, a process known as cryopreservation.
"Potential applications for this new class of antifreeze molecules are abundant," said Walters in a release. "In terms of cryopreservation, we may be able to increase viability and enhance survivorship of cells and tissues from other organisms under freezing conditions."
This specific antifreeze molecule is a combination of saccharides and fatty acids. As a consequence, it is smaller than most proteins and its chemical composition could be replicated in a lab for easier commercial production. Small chains of sugars can be readily synthesized in the laboratory, making them cheaper and easier to manufacture than biologically assembled molecules like proteins.
A multitude of organisms such as fish, insects, plants, fungi and bacteria contain antifreeze molecules. Past efforts at isolating the antifreeze molecules have been unsuccessful, in part because those molecules may show up only when triggered by extreme environmental factors.