Accordingly, pentoses such as ribose are known to form stable borate complexes. The binding preferences of borate to pentoses has been determined to be ribose > lyxose > arabinose > xylose (Li, 2005). The ribose molecule may be stabilized by borate that binds to the 2′ and 3′ positions of the furanose form of ribose. The fact that ribose is stabilized by borate selleck may change our opinion of the formose reaction as a seemingly random and nonselective reaction into a very precise geochemical pre-RNA process. The formose reaction was, for a while, an outdated concept for abiotic synthesis of carbohydrates. However, because of borate complex formation it is still possible

that it is responsible for prebiotic formation of ribose in natural environments and that this may occur in close vicinity to abiotic purine synthesis and phosphorylation processes in alkaline hydrothermal environments of convergent margins. Once pyrophosphate is available, phosphorylation of ribose and/or nucleosides may occur. Li, Q., Ricardo, A., Benner, S.A., Winefordner, J.D., and Powell, D.H. (2005). Desorption/ionization on porous silicon mass spectrometry studies on pentose–borate complexes. Analytical Chemistry 77, 4503–4508. E-mail: nils.​holm@geo.​su.​se Models of Abiotic Synthesis of Adenosine Mono-, selleck compound Di- and Triphosphate Taisiya A. Telegina, Michael P. Kolesnikov, Mikhail S. Kritsky A.N. Bach Institute of Biochemistry, Russian Academy of Sciences,

Moscow, Russia The first step of ATP synthesis, i.e. the de novo formation of 5′-AMP molecule, is achieved in organisms via a multistage enzymatic process in which adenine heterocycle is built up on the ribose-5-phosphate pedestal from C and N atoms originating from formic acid, carbon dioxide, Vadimezan concentration glutamine, glycine and aspartic acid. We showed that under abiotic conditions

5′-AMP can be formed from the same precursors, i.e. the mixture of ribose, potassium phosphate, sodium bicarbonate, ammonium formate, glutamine, glycine and aspartic acid. After 40 min incubation of anhydrous mixture of these compounds at 85°C in oxygen-free atmosphere, 5′-AMP was identified among reaction products by using HPLC for isolation of this nucleotide. The phosphorylation of this nucleotide product gave rise to ATP which was detected by a highly specific luciferin-luciferase luminescence Niclosamide test. The yield of 5′-AMP (calculated to initial ribose content) was about 3–5%. The efficiency of the same set of chemical precursors for abiotic and biological synthesis of 5′-AMP is of interest in context of the development of metabolic pathway of purine nucleotides biosynthesis in early stages of evolution. According to results of laboratory modeling, in prebiotic world there existed various options for photon energy conservation in energy rich phosphoanhydride bonds of ADP and ATP including the photophosphorylation processes, which did not need any organic sensitizers.