Keefe A D, Miller S L
Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla 92093-0317, USA.
J Mol Evol. 1995 Dec;41(6):693-702. doi: 10.1007/BF00173147.
It is widely held that there was a phosphate compound in prebiotic chemistry that played the role of adenosine triphosphate and that the first living organisms had ribose-phosphate in the backbone of their genetic material. However, there are no known efficient prebiotic synthesis of high-energy phosphates or phosphate esters. We review the occurrence of phosphates in Nature, the efficiency of the volcanic synthesis of P4O10, the efficiency of polyphosphate synthesis by heating phosphate minerals under geological conditions, and the use of high-energy organic compounds such as cyanamide or hydrogen cyanide. These are shown to be inefficient processes especially when the hydrolysis of the polyphosphates is taken into account. For example, if a whole atmosphere of methane or carbon monoxide were converted to cyanide which somehow synthesized polyphosphates quantitatively, the polyphosphate concentration in the ocean would still have been insignificant. We also attempted to find more efficient high-energy polymerizing agents by spark discharge syntheses, but without success. There may still be undiscovered robust prebiotic syntheses of polyphosphates, or mechanisms for concentrating them, but we conclude that phosphate esters may not have been constituents of the first genetic material. Phosphoanhydrides are also unlikely as prebiotic energy sources.
人们普遍认为，在生命起源前的化学过程中存在一种磷酸盐化合物，它起到了三磷酸腺苷的作用，并且第一批生物体的遗传物质主链中含有核糖 - 磷酸。然而，目前尚无已知的高效的生命起源前的高能磷酸盐或磷酸酯合成方法。我们综述了自然界中磷酸盐的存在情况、火山合成五氧化二磷的效率、在地质条件下加热磷酸盐矿物合成多磷酸盐的效率，以及使用氰胺或氰化氢等高能量有机化合物的情况。结果表明，这些过程效率低下，尤其是考虑到多磷酸盐的水解时。例如，如果整个甲烷或一氧化碳大气都转化为氰化物，并且以某种方式定量合成多磷酸盐，海洋中的多磷酸盐浓度仍然会微不足道。我们还试图通过火花放电合成找到更有效的高能聚合剂，但未成功。可能仍然存在未被发现的强大的生命起源前的多磷酸盐合成方法，或者将它们浓缩的机制，但我们得出结论，磷酸酯可能不是第一批遗传物质的组成部分。磷酐作为生命起源前的能量来源也不太可能。
