Yancey P H, Clark M E, Hand S C, Bowlus R D, Somero G N
Science. 1982 Sep 24;217(4566):1214-22. doi: 10.1126/science.7112124.
Striking convergent evolution is found in the properties of the organic osmotic solute (osmolyte) systems observed in bacteria, plants, and animals. Polyhydric alcohols, free amino acids and their derivatives, and combinations of urea and methylamines are the three types of osmolyte systems found in all water-stressed organisms except the halobacteria. The selective advantages of the organic osmolyte systems are, first, a compatibility with macromolecular structure and function at high or variable (or both) osmolyte concentrations, and, second, greatly reduced needs for modifying proteins to function in concentrated intracellular solutions. Osmolyte compatibility is proposed to result from the absence of osmolyte interactions with substrates and cofactors, and the nonperturbing or favorable effects of osmolytes on macromolecular-solvent interactions.
在细菌、植物和动物中观察到的有机渗透溶质（渗透剂）系统的特性存在显著的趋同进化。多元醇、游离氨基酸及其衍生物，以及尿素和甲胺的组合是在除嗜盐菌之外的所有水分胁迫生物中发现的三种渗透剂系统。有机渗透剂系统的选择性优势首先在于，在高渗透剂浓度或可变渗透剂浓度（或两者兼具）下与大分子结构和功能的兼容性；其次在于，大大减少了在浓缩细胞内溶液中发挥功能时对蛋白质进行修饰的需求。有人提出，渗透剂兼容性源于渗透剂与底物和辅因子之间不存在相互作用，以及渗透剂对大分子 - 溶剂相互作用无干扰或有有利影响。
