Earth has several environments that are potentially hostile to life. The survival of organisms has required the expression of proteins that are adapted to function under extreme temperature, pH, pressure or ionic strength. However, the origin of such adaptations remains, in most cases, an open question. This Review presents a detailed analysis of the specialized enzymes that are able to maintain high catalytic rates at low temperatures and highlights the important role that computational studies have in uncovering the evolutionary principles behind the cold adaptation of enzymes. Although often highly homologous to their mesophilic counterparts, these cold-adapted enzymes have characteristic and universal properties that reflect their evolutionary optimization. In addition to exhibiting maximum reaction rates at lower temperatures, cold-adapted enzymes are more heat-labile and their catalytic mechanisms have distinct signatures in terms of the thermodynamic activation parameters. The structural origins of these properties have been elusive but are hypothesized to be related to protein flexibility.

地球有几种可能对生命有害的环境。生物的生存需要表达能够在极端温度，pH，压力或离子强度下起作用的蛋白质。然而，在大多数情况下，这种适应的起源仍然是一个悬而未决的问题。这篇综述对能够在低温下保持高催化速率的特殊酶进行了详细分析，并强调了计算研究在揭示酶冷适应背后的进化原理方面的重要作用。尽管这些冷适应酶通常与中温对应物高度同源，但它们具有反映其进化优化的特征和通用特性。除了在较低温度下展现出最大的反应速率外，适应冷的酶具有更高的热不稳定性，其催化机理在热力学激活参数方面具有独特的特征。这些特性的结构起源难以捉摸，但据推测与蛋白质的柔韧性有关。