X-Message-Number: 17329
From: "John Clark" <>
Subject: Synthetic Antifreeze Could Prevent Ice Growth 
Date: Mon, 20 Aug 2001 10:32:10 -0400

Source:   American Chemical Society (http://www.acs.org/)


A fish swimming in icy polar waters is helping scientists find ways to
protect food from freezer burn, save fruit crops from frost, and use
low temperature storage in complicated medical procedures like human
organ transplants, researchers report.

A way to make large amounts of artificial antifreeze safe enough to use
in living organisms has been developed by researchers looking at the
 biological  antifreeze used by Arctic and Antarctic teleost fish, according
to a report in the September/October issue of Bioconjugate Chemistry,
a peer-reviewed journal of the American Chemical Society, the world s
largest scientific society. The report will be presented August 30 at the
Society s 222nd national meeting in Chicago.

A big problem with the freezing process in medical and industrial applications

is that the formation of ice crystals damages living material. Certain organisms
like the fish, however, have developed a successful defense   a naturally
produced antifreeze called antifreeze glycoprotein, or AFGP. The biological
AFGP in fish, and in some amphibians, plants and insects, prevents the growth
of ice in those life forms, scientists have found.

While researchers have known about the glycoproteins for many years, they
have been unable to produce large or stable enough copies for commercial
applications, and the use of the natural compounds themselves is too labor
and cost-intensive to be practical.

Even though researchers do not precisely understand the mechanism by which

the AFGPs function, they have been able to modify the structure of the fish AFGP

enough to build a longer lasting mimic, a lot like the native AFGPs, according 
to
Robert Ben, Ph.D., who led the research team from the State University of
New York in Binghamton. Ben says the new method can easily produce large
quantities of the compound that yield only to inhospitable conditions like
extremely high or low temperatures.

The new synthetic proteins  are dramatically different from the natural
antifreeze glycoprotein, but still display the ability to inhibit ice growth, 
Ben said.  This is very significant and may mean a real leap forward in
the design of such compounds; we think this is incredibly promising
for a number of applications. 

Among potential uses for synthetic AFGP s: a frost protection spray
for crops that could expand growing seasons and even allow fruits to
grow in more northern climates. He also believes elimination of freezer
burn is possible, along with the preservation of human organs and
tissues for transplantation.

In essence, Ben reports, the new method replaces a weak chemical bond
in the natural antifreeze with a far more durable one, but further study to
develop greater strength in the artificial glycoprotein is ongoing. He said
he anticipates that researchers will construct different variations of the
modified antifreeze for different applications.

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