摘要
It has been hypothesized that before the emergence of modern DNA–RNA–protein life, biology evolved from an “RNA world.” However, synthesizing RNA and other organophosphates under plausible early Earth conditions has proved difficult, with the incorporation of phosphorus (P) causing a particular problem because phosphate, where most environmental P resides, is relatively insoluble and unreactive. Recently, it has been proposed that during the Hadean–Archean heavy bombardment by extraterrestrial impactors, meteorites would have provided reactive P in the form of the iron–nickel phosphide mineral schreibersite. This reacts in water, releasing soluble and reactive reduced P species, such as phosphite, that could then be readily incorporated into prebiotic molecules. Here, we report the occurrence of phosphite in early Archean marine carbonates at levels indicating that this was an abundant dissolved species in the ocean before 3.5 Ga. Additionally, we show that schreibersite readily reacts with an aqueous solution of glycerol to generate phosphite and the membrane biomolecule glycerol–phosphate under mild thermal conditions, with this synthesis using a mineral source of P. Phosphite derived from schreibersite was, hence, a plausible reagent in the prebiotic synthesis of phosphorylated biomolecules and was also present on the early Earth in quantities large enough to have affected the redox state of P in the ocean. Phosphorylated biomolecules like RNA may, thus, have first formed from the reaction of reduced P species with the prebiotic organic milieu on the early Earth.
摘要译文
已经假设在现代DNA-RNA蛋白质生命的出现之前，生物学从“RNA世界”中发展出来。然而，在合理的早期地球条件下合成RNA和其他有机磷酸盐已经证明是困难的，因为磷（P）引起了特定问题，因为磷酸盐在大多数环境P所在的情况下，相对不溶于不溶于不溶胀和不可溶剂。最近，已经提出，在哈维斯 - Archean重量轰炸期间，陨石在铁镍磷化物矿物酶的形式提供反应性P.这在水中反应，释放可溶性和反应性降低的P物种，例如亚磷酸盐，然后可以容易地掺入益生元分子中。在这里，我们在3.5克之前报告了在水平的早期原始海洋碳酸盐中亚磷酸盐的发生，这是3.5克之前的海洋中的一种丰富的溶解物种。另外，Schreibersite易于与甘油水溶液反应产生亚磷酸盐和膜的含水溶液。生物分子甘油磷酸盐在温和的热条件下，使用衍生自苯胺的矿物来源的矿物来源是，因此，在益生菌合成的磷酸化生物分子中的合理试剂也足够大的数量。影响了海洋中P的氧化还原状态。因此，磷酸化的生物分子如图所示，首先是由早期地球上与益生元有机环境的降低的P种不同的反应形成。
Matthew A. Pasek [1];Jelte P. Harnmeijer [2];Roger Buick [3];Maheen Gull [1];Zachary Atlas [1]. Evidence for reactive reduced phosphorus species in the early Archean ocean[J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2013,110(25): 10089-10094