Psychrophiles Optimun15° C or lower · Maximun<20° Minimun<0° Many are very sensitive to moderate temperatures Enzyme denaturation at moderate temp Greater proportion of unsaturated fatty acids in membrane phospholipids Ocean depths: constant temp <5CPsychrophiles • Optimum 15°C or lower • Maximum <20° • Minimum 0° • Many are very sensitive to moderate temperatures • Enzyme denaturation at moderate temp • Greater proportion of unsaturated fatty acids in membrane phospholipids • Ocean depths: constant temp <5oC