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COLD EXTREMOPHILES. "Psychrophiles have successfully overcome two main challenges: first, low temperature, because any decrease in temperature exponentially affects the rate of biochemical reactions; and second, the viscosity of aqueous environments, which increases by a factor higher than two between 37 °C and 0 °C." https://lnkd.in/dxAsq4S View in LinkedIn

COLD ADAPTED EXTREMOPHILES are frequently marine, and salt water presents special challenges. Salt water freezes at lower temperatures than fresh water. Freezing seas segregate salt and fresh water during ice formation, so when it melts, the organisms get an osmotic shock, just to add to their discomfort. View in LinkedIn

EXTREME INSECTS. "During the extreme winter months, the spruce budworm resists freezing at temperatures approaching –30 °C. The Alaskan beetle Upis ceramboides can survive in a temperature of –60 °C by using antifreeze agents that are not proteins." https://lnkd.in/dtV8vVP View in LinkedIn

HETEROGENEITY OF SEA ICE. Sea ice is enormously varied, ever-changing, highly complex environment as assessed by numerous parameters. It presents numerous very different habitats for microorganisms, with different chemistry, ice structures, and physical properties. https://lnkd.in/dwnrxh3 View in LinkedIn

LIQUID NITROGEN. "Many microbes and cell lines can be preserved successfully at -196 'C (liquid nitrogen), but the lowest recorded temperature for active microbial communities is substantially higher, at -18 'C ... ice crystals can rip cell membranes, and solution chemistry stops in the absence of liquid water. Freezing of intracellular water is almost invariably lethal." https://lnkd.in/diUg6FS View in LinkedIn

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