期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2001
卷号：98
期号：10
页码：5487-5490
DOI：10.1073/pnas.101085998
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The emergence of biochemical homochirality was a key step in the origin of life, yet prebiotic mechanisms for chiral separation are not well constrained. Here we demonstrate a geochemically plausible scenario for chiral separation of amino acids by adsorption on mineral surfaces. Crystals of the common rock-forming mineral calcite (CaCO3), when immersed in a racemic aspartic acid solution, display significant adsorption and chiral selectivity of D- and L-enantiomers on pairs of mirror-related crystal-growth surfaces. This selective adsorption is greater on crystals with terraced surface textures, which indicates that D- and L-aspartic acid concentrate along step-like linear growth features. Thus, selective adsorption of linear arrays of D- and L-amino acids on calcite, with subsequent condensation polymerization, represents a plausible geochemical mechanism for the production of homochiral polypeptides on the prebiotic Earth.
