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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

FINE BALANCE. "An appropriate level of cytoplasmic membrane permeability is essential for the provision of energy, metabolites, and intracellular environment needed for metabolism and, consequently, is a determining factor of maximum temperature for growth ... the role of the cell membrane in survival is to adjust lipid composition in order to maintain constant homeo-proton permeability." https://lnkd.in/dz9R9uY View in LinkedIn

LIQUID CRYSTAL MEMBRANES. "Increased contents of unsaturated, polyunsaturated, and methyl-branched fatty acids with high proportion of cis-unsaturated double bonds and antesio-branched fatty acids allow the membrane to remain in a liquid crystalline state (through reduced gel-liquid-crystalline phase transition temperature, Tm) at low temperatures." https://lnkd.in/dz9R9uY View in LinkedIn

COLD ADAPTED MEMBRANE LIPIDS. "In general, lower growth temperatures produce a higher content of unsaturated, polyunsaturated and methyl-branched fatty acids, and/or a shorter acyl-chain length, with studies reporting a high proportion of cis-unsaturated double-bonds and antesio-branched fatty acids." https://lnkd.in/dxAsq4S View in LinkedIn

EXTREME COLD MEMBRANES. "Membranes and enzymes become rigid at low temperatures. Reduced membrane fluidity results in reduced membrane permeability and adversely affects the transport of nutrients and waste products across the membrane." https://lnkd.in/dz9R9uY View in LinkedIn

FREEZING AND VISCOUS NICHES. "Psychrophilic Archaea, cold-loving organisms ... inhabit areas below 15 'C and often thrive at temperatures near the freezing point of water. Permanent exposure to cold has necessitated adaptations to overcome two main challenges: low temperature and the viscosity of aqueous environments." https://lnkd.in/dz9R9uY View in LinkedIn

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