Canadian Researchers Find Anti-Freeze in Fleas
TORONTO Tiny fleas that survive on fungus found under a blanket of snow contain a unique antifreeze that could have implications for farming or transplant surgery, Canadian researchers said on Wednesday.
The researchers, whose a report is published in the latest edition of Science, said their findings could help protect plants or animals from frost, or allow donated transplant organs to be stored and transported at lower temperatures.
The six-legged snow fleas are between 1 and 2 millimeters long (0.04 to 0.08 inches), with six legs and no wings.
They are also known as springtails because they have an abdominal spring called a furcula that lets them jump away from predators.
Their bodies contain proteins that limit the growth of ice by lowering the freezing point of fluids by 6 degrees Celsius (11 degrees Fahrenheit), said the researchers, from Queen's University in Kingston, Ontario.
One practical application of the study could be to store transplant organs at cooler temperatures to preserve them for longer.
"If you can profuse, or basically run a solution with an antifreeze protein and flood an organ with it, you might then be able to store it at lower temperatures and the antifreeze would prevent the organ from actually freezing," said Laurie Graham, one of the two researchers who carried out the study.
"Theoretically, with this antifreeze protein we might be able to store an organ at minus 6 degrees (21 degrees Fahrenheit). Hopefully, it would be able to last longer so that you would have longer to do tissue matching to get the organ to the patient and just increase the shelf life of organs."
She said frozen foods could also benefit from the discovery, if the antifreeze, which she derived from crushed snow fleas, can be used to inhibit freezer burn.
Another possible application could be in crops, allowing fruit trees to survive a cold snap.
"If you were able to genetically modify any crop that was susceptible to frost you may be able to generate a crop that's not so sensitive," Graham said.
The researchers found that the antifreeze proteins in the snow fleas were different from those in beetles and moths, prompting Graham and her research partner, Queen's University biochemistry Professor Peter Davies, to conclude that these antifreeze proteins evolved independently in the snow fleas.
"There would have been climate change and the organisms were challenged by a new environment," Graham said. It's almost like nature has had to reinvent the wheel."
The snow flea is wingless and is not related to the biting flea, which is a true insect.