Navigation Links
Dance of water molecules turns fire-colored beetles into antifreeze artists

Certain plants and animals protect themselves against temperatures below freezing with antifreeze proteins. How the larva of the beetle Dendroides canadensis manages to withstand temperatures down to -30 degrees Celsius is reported by an international team of researchers led by Prof. Dr. Martina Havenith from the Department of Physical Chemistry II at the Ruhr-Universitt in the journal PNAS. Together with American colleagues, the RUB-researchers showed that interactions between the antifreeze proteins and water molecules contribute significantly to protection against the cold. Previously, it was assumed that the effect was only achieved through direct contact of the protein with ice crystals. The team obtained the results through a combination of terahertz spectroscopy and molecular dynamics simulations.

Protein-ice interaction: locally and over longer distances

The structure of the fire beetle antifreeze proteins resembles a triangular prism. The ice binding surface of the "prism" contains many exposed side chains, as fragments of the amino acid threonine protrude from the surface here. These side chains bind ice crystals. Up until now, it was assumed that the antifreeze proteins only interact locally with nano ice crystals and thus prevent the formation of larger ice crystals. The international group of researchers showed, however, that this interaction also takes place between proteins and ice crystals over longer distances via water molecules, which also contributes to the freeze-protection.

The dynamics of the water molecules is important for the freeze-protection

Close to the ice binding surface, the scientists observed a much slower movement of the water molecules, which differed significantly from the water movements on the non-ice-binding sides of the protein and of free water. The lower the temperature, the slower the water moved. "We suspect that the calmer water movement on the binding surface of the protein facilitates the docking of the nano ice crystals," Martina Havenith speculated. In accordance with this, the researchers found little change in the movement of the water molecules in an inactive mutant of the antifreeze protein.

More efficient than in fish

The antifreeze proteins of the fire-coloured beetle are ten to one hundred times more active than those of Arctic and Antarctic fish that need to protect themselves against temperatures of -1.9 degrees Celsius. The insects achieve this high antifreeze activity through the combination of the two strategies: direct interaction between proteins and ice and interaction via water molecules.

Observing the role of the solvent

"The special role of water in natural antifreeze is an excellent example demonstrating that when looking at the function of a biomolecule, you not only have to consider its 3D structure, but also its entire environment - especially the solvent; in this case water," Prof. Havenith said. This topic is the focus of the cluster of excellence RESOLV, which was launched on the 1st November 2012 at the RUB and whose spokesperson is Martina Havenith. The current studies were funded by the Volkswagen Foundation.


Contact: Martina Havenith
Ruhr-University Bochum

Related biology news :

1. A mating dance with Popeye arms
2. New stem cell technique promises abundance of key heart cells
3. Lyme retreatment guidance may be flawed
4. Microchoreography: Researchers use synthetic molecule to guide cellular dance
5. Ozone treated water v. lethal microbial material
6. Unexpected crustacean diversity discovered in northern freshwater ecosystems
7. New methods for better purification of wastewater
8. Costs for changing pollution criteria in Florida waters likely to exceed EPA estimates
9. Current water resources in Europe and Africa
10. UC research: Tracking Lake Erie water snake in fight against invasive fish
11. Study confirms oil from Deepwater Horizon disaster entered food chain in the Gulf of Mexico
Post Your Comments:
(Date:11/18/2015)... , Nov. 18, 2015  As new scientific ... children, doctors and other healthcare providers face challenges in ... families and patients. In addition, as more children continue ... a patient,s adulthood and old age. John ... The Children,s Hospital of Philadelphia (CHOP) . ...
(Date:11/17/2015)... , November 17, 2015 Paris ... 2015.   --> Paris from 17 ... DERMALOG, the biometrics innovation leader, has invented the first ... fingerprints on the same scanning surface. Until now two different ... Now one scanner can capture both on the same ...
(Date:11/17/2015)... -- Vigilant Solutions announces today that Mr. Dick W. ... --> --> Mr. Boyce ... at TPG Capital, one of the largest global investment ... revenue.  He founded and led TPG,s Operating Group, which ... 1997 to 2013.  In his first role, he served ...
Breaking Biology News(10 mins):
(Date:11/27/2015)... ... 27, 2015 , ... Pittcon is pleased to announce the ... in symposia, oral sessions, workshops, awards, and posters. The core of the ... such as, but not limited to, biotechnology, biomedical, drug discovery, environmental, food science, ...
(Date:11/26/2015)... CHESHAM , England , November 26, ... Lightpoint Medical, an innovative medical device company specializing in ... Euro grant from the European Commission as part of the ... enabling the company to carry out a large-scale clinical trial ... -->      (Logo: , ...
(Date:11/25/2015)... -- 2 nouvelles études permettent d , ... entre les souches bactériennes retrouvées dans la plaque ... . Ces recherches  ouvrent une nouvelle voie ... efficace de l,un des problèmes de santé les ...    --> 2 nouvelles études permettent d ...
(Date:11/25/2015)... Nov. 25, 2015  Neurocrine Biosciences, Inc. (Nasdaq: ... President and CEO of Neurocrine Biosciences, will be presenting ... New York . ... website approximately 5 minutes prior to the presentation to ... the presentation will be available on the website approximately ...
Breaking Biology Technology: