Antifreeze proteins (AFPs) enhance the survival of organisms inhabiting cold environments by affecting the formation and/or structure of ice. We report the crystal structure of the first multi-domain AFP that has been characterized. The two ice binding domains are structurally similar. Each consists of an irregular β-helix with a triangular cross-section and a long α-helix that runs parallel on...

The Southern Ocean around Antarctica is among the most rapidly warming regions on Earth, but has experienced episodic climate change during the past 40 million years. It remains unclear how ancient periods of climate change have shaped Antarctic biodiversity. The origin of antifreeze glycoproteins (AFGPs) in Antarctic notothenioid fishes has become a classic example of how the evolution of a ke...

Mirror matter admixtures and isospin breaking in the |∆I| = 1/2 rule in Ω − two body non-leptonic decays Abstract We discuss a description of Ω − two body non-leptonic decays based on possible , albeit tiny, admixtures of mirror matter in ordinary hadrons. The |∆I| = 1/2 rule enhancement is obtained as a result of isospin symmetry and, more importantly, the rather large observed deviations from...

The ability to control extracellular ice formation during freezing is critical to the survival of freezing-tolerant plants. Antifreeze proteins, which are proteins that have the ability to retard ice crystal growth, were recently identified as the most abundant apoplastic proteins in cold-acclimated winter rye (Secale cereale L.) leaves. In the experiments reported here, amino-terminal sequence...

A cDNA made to antifreeze protein mRNA of the winter flounder was cloned in the plasmid pBR322 and its sequence was determined by the method of Maxam and Gilbert. Its sequence codes for a precursor protein that is 82 amino acids in length. This precursor has both a signal polypeptide and a prosequence before the mature protein of 38 amino acid residues. The mature protein matches in composition...

The ability of natural peptides and proteins to influence the formation of inorganic crystalline materials has prompted the design of synthetic compounds for the regulation of crystal growth, including the freezing of water and growth of ice crystals. Despite their versatility and ease of structural modification, peptidomimetic oligomers have not yet been explored extensively as crystallization...

Preservation of DNA in bulk environmental samples is conventionally achieved using ethanol; however, transportation restrictions on ethanol, particularly from remote locations, are problematic, and ethanol requires a lengthy evaporation period to avoid polymerase chain reaction inhibition. We examined the efficacy an easily accessible, non-toxic, propylene glycol-based antifreeze as alternative...

Antifreeze thermal electric drills have a long history of ice drilling in temperate, subpolar and polar glaciers. Shallow, intermediate and deep ice cores have been obtained in Arctic, Antarctic and on high elevation glaciers. Many merits and drawbacks of antifreeze thermal technology have been discovered over the past 25 years. A modified version of the antifreeze thermal electric ice coring d...