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DIVERSE FAMILY. "Antifreeze proteins adsorb to the surface of ice crystals and prevent their growth. This adsorption lowers the freezing temperature of a solution below its melting point. Despite their common function, AFPs display remarkable diversity in their tertiary structures. This diversity results partly from their independent evolutionary origins and partly from the surface heterogeneity of their natural ligand, ice." http://www.pnas.org/content/108/18/7363.full View in LinkedIn

"THE LOWEST TEMPERATURE LIMIT for life seems to be around −20 °C, which is the value reported for bacteria living in permafrost soil and in sea ice. Microbial activity at such temperatures is restricted to small amounts of unfrozen water inside the permafrost soil or the ice, and to brine channels." https://lnkd.in/dxAsq4S View in LinkedIn

HARNESSING THERMODYNAMICS. "The addition of AFPs at the interface between solid ice and liquid water inhibits the thermodynamically favored growth of the ice crystal. Ice growth is kinetically inhibited by the AFPs covering the water-accessible surfaces of ice." https://lnkd.in/dtV8vVP View in LinkedIn

FRAGMENT FROM NATURE continues with extremophyle adaptions. As the first and most important barrier to the outside world, it is of little surprise that cell membranes in these extraordinary creatures are highly adapted for conditions too harsh for any other life forms. Inside the cell, other adaptations of proteins, nucleic acids, and enzymes are also required to exploit harsh niches. View in LinkedIn

THERMAL HYSTERESIS. "Antifreeze proteins (AFPs) are a structurally diverse group of ice-binding proteins that inhibit the growth of ice either by depressing the freezing point of the solution [thermal hysteresis (TH) activity] or by inhibiting the recrystallization (RI activity) of ice grains." https://lnkd.in/d933hpj View in LinkedIn

DROPLETON QUANTUM FOG. "They form a “quantum fog” of electrons and holes that flow around each other and even ripple like a liquid, rather than existing as discrete pairs. However, unlike liquids we are familiar with, dropletons a finite size, outside which the electron/hole association breaks down." https://lnkd.in/dR2cJKA View in LinkedIn

ANTIFREEZE PROTEINS "bind to ice crystals and cause differences between the freezing point and melting point (TH: thermal hysteresis) through an adsorption-inhibition mechanism. Arctic yeast Leucosporidium sp. produces a glycosylated ice-binding protein ... which can lower the freezing point below the melting point once it binds to ice." https://lnkd.in/dWNCJJV View in LinkedIn

RAOULT'S LAW: freezing point depression. "By dissolving a solute in a solvent, the freezing point of the solution is lowered. The reason for this lower freezing point is that when a liquid freezes, the molecules form a pure solid sample of solvent. Those molecules still in the liquid phase still have solute molecules at the liquid-solid surface, so more molecules will go from solid phase to liquid phase." https://cssac.unc.edu/programs/learning-center/Resources/Study/Guides/Chemistry%20102/Solutions View in LinkedIn

ANTIFREEZE PROTEINS. "The debilitating effects of ice crystallization pose a major threat to all psychrophilic organisms. Archaeal homologues of antifreeze proteins (AFPs) present in Bacteria, plants and fish are believed to function similarly in psychrophilic Archaea and allow for their growth and survival in subzero environments." https://lnkd.in/dz9R9uY View in LinkedIn

COLD SHOCK PROTEINS. "The exposure of mesophilic organisms to sudden temperature changes, both upshifts and downshifts, induces the transient overexpression of several proteins—known respectively as heat-shock proteins (Hsps) or cold-shock proteins (Csps)—that are involved in various cellular processes such as transcription, translation, protein folding and the regulation of membrane fluidity." https://lnkd.in/dxAsq4S View in LinkedIn