Psychrophilic organisms are widely distributed in nature as a large part of the Earth's surface is at temperatures around 0°C. These cold-loving microorganisms face the thermodynamic challenge to maintain enzyme-catalyzed reactions and metabolic rates compatible with sustained growth near or below the freezing point of pure water. Typically, the rate of a biochemical reaction decreases 2–3-fold when the temperature is lowered by 10°C.