Spectrométries et Dynamique Moléculaire, Physique des Interactions Ioniques et Moléculaires Université de Provence, Université Aix-Marseille I, Centre Saint-Jérôme, Case 252, 13397, Marseille, France.
Amino Acids. 2012 Jun;42(6):2331-41. doi: 10.1007/s00726-011-0975-2. Epub 2011 Jul 16.
The reaction of cyanate with C-terminal carboxyl groups of peptides in aqueous solution was considered as a potential pathway for the abiotic formation of peptide bonds under the condition of the primitive Earth. The catalytic effect of dicarboxylic acids on cyanate hydrolysis was definitely attributed to intramolecular nucleophilic catalysis by the observation of the 1H-NMR signal of succinic anhydride when reacting succinic acid with KOCN in aqueous solution (pH 2.2-5.5). The formation of amide bonds was noticed when adding amino acids or amino acid derivatives into the solution. The reaction of N-acyl aspartic acid derivatives was observed to proceed similarly and the scope of the cyanate-promoted reaction was analyzed from the standpoint of prebiotic peptide formation. The role of cyanate in activating peptide C-terminus constitutes a proof of principle that intramolecular reactions of adducts of peptides C-terminal carboxyl groups with activating agents represent a pathway for peptide activation in aqueous solution, the relevance of which is discussed in connexion with the issue of the emergence of homochirality.
氰酸盐与水溶液中肽的 C 末端羧基之间的反应被认为是在原始地球上肽键在非生物条件下形成的一种潜在途径。通过观察琥珀酸与 KOCN 在水溶液（pH 2.2-5.5）中反应时琥珀酸酐的 1H-NMR 信号，确定了二酸对氰酸盐水解的催化作用归因于分子内亲核催化。当向溶液中添加氨基酸或氨基酸衍生物时，注意到酰胺键的形成。还观察到 N-酰基天冬氨酸衍生物的反应类似进行，并从前生物肽形成的角度分析了氰酸盐促进反应的范围。氰酸盐在激活肽 C 末端中的作用构成了一个原理的证明，即肽 C 末端羧基与激活剂的加合物的分子内反应代表了在水溶液中肽激活的途径，该途径与手性起源问题的相关性进行了讨论。
