de Graaf R M, Visscher J, Schwartz A W
Faculty of Science, University of Nijmegen, The Netherlands.
Nature. 1995 Nov 30;378(6556):474-7. doi: 10.1038/378474a0.
The insolubility of calcium phosphate in water is a significant stumbling block in the chemistry required for the origin of life. The discovery of alkyl phosphonic acids in the Murchison meteorite suggests the possibility of delivery of these water-soluble, phosphorus-containing molecules by meteorites or comets to the early Earth. This could have provided a supply of organic phosphorus for the earliest stages of chemical evolution; although probably not components of early genetic systems, phosphonic acids may have been precursors to the first nucleic acids. Here we report the synthesis of several phosphonic acids, including the most abundant found in the Murchison meteorite, by ultraviolet irradiation of orthophosphorous acid in the presence of formaldehyde, primary alcohols, or acetone. We argue that similar reactions might explain the presence of phosphonic acids in Murchison, and could also have occurred on the prebiotic Earth.
磷酸钙在水中的不溶性是生命起源所需化学过程中的一个重大障碍。在默奇森陨石中发现烷基膦酸表明，陨石或彗星有可能将这些水溶性含磷分子输送到早期地球。这可能为化学进化的最早阶段提供了有机磷供应；膦酸虽然可能不是早期遗传系统的组成部分，但可能是第一种核酸的前体。在此，我们报告了在甲醛、伯醇或丙酮存在下，通过紫外线照射亚磷酸合成了几种膦酸，包括在默奇森陨石中发现的含量最丰富的那种。我们认为，类似的反应可能解释了默奇森陨石中膦酸的存在，并且也可能发生在生命起源前的地球上。
