模拟生命起源前的自然蒸干现象,使甘油和癸酸在近中性混合溶液中发生脱水缩合,生成了原始细胞膜前驱体癸酸甘油酯.随着温度升高到90 ℃,主产物一癸酸甘油酯的产率可达4.7%.对反应后的样品直接进行再水化时,能观测到形态良好的囊泡,证实生成微量癸酸甘油酯的混合物体系能使两亲分子在更低浓度下自组装形成囊泡.当蒸干体系再水化过程中存在有机物溶质时,溶液体系中的有机化合物能在囊泡形成过程中被封装起来,因而膜结构为生命物质的稳定存在提供了保护场所,蒸干再水化的条件有利于增加细胞生命起源过程中两亲分子的稳定性.%Nonenzymatic dehydration reactions of decanoic acid with glycerol has been reported to occur under mimicked prebiotic conditions at near neutral pH, yielding more evolved membrane precursor compound glyceryl decanoates. Two isomers of glyceryl monodecanoate were the main products after the condensation reactions,and the yield of glyceryl monodecanoates could be increased to 4.7% with temperature rising to 90℃. Vesicles were observed when the mixture after reactions was rehydrated. Experiments demonstrate that trace glyceryl decanoates produced in the mixture play a great role in robust self-assembly process, it is the existence of such lipid products that makes a lower critical vesicle concentration. Meanwhile, organic com-pounds have been encapsulated during the self-assembly of vesicles,so membranous structures provid a place for organic compounds to exist stably. The dehydration reactions at near neutral pH,followed by rehydration, are suitable for increasing protocell membrane stability to environment.It implies that the condensation reaction is plausible for yielding more complex amphiphiles and the appearance of membrane structures on the early earth.
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