Month: September 2022

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

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

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

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

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 "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

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

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

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

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