Phosphorus Compounds in Chemical Evolution

In model experiments, the conditions were found for non-enzymatic synthesis of pyrophosphate, by the phosphorylation of orthophosphate in the presence of certain cations, and by means of ATP and PolyP3, respectively (Lowenstein, 1958 Tetas and Lowenstein, 1963 Le Port et al, 1971). 

It was shown experimentally that this reaction proceeded much more rapidly with PolyP, as follows (Kulaev and Skryabin, 1971, 1974)  

It was observed that radioactive pyrophosphate was formed non-enzymatically in substantial amounts when [32P] orthophosphate was phosphorylated by incubation with PolyP40 in an aqueous solution at 37 °C for 15 h at pH 9 in the presence of certain divalent cations. The 16-30 % of initial high-molecular-weight polyphosphate was utilized in phosphorylation, and among the cations tested, the greatest amount of incorporation was achieved with Ba2+ (33 %) and the least with Mg2+ (16 %)  

It is interesting that, when organic and inorganic tripolyphosphates were employed under the same conditions, only 0.2-0.6 % of the phosphate donor was utilized (Lowenstein, 1958, 1960 Tetas and Lowenstein, 1963 Le Port et al., 1971). Our experimental findings thus lead to the conclusion that, as the Earth cooled and a hydrosphere was formed on its surface, a variety of transphosphorylation reactions became possible in the primeval ocean, in particular, the phosphorylation of Pi by PolyP to give pyrophosphate. It should be noted that the non-enzymatic synthesis of PolyP and pyrophosphate on the primitive Earth could take place not only in solutions, but also on the surface of some minerals with anion-exchange properties (Arrhenius et al., 1993,1997). 

Some experiments have shown efficient condensation of simple aldehyde phosphates in the hydroxide mineral (such as hydrotalcite, ([ Mg2 AKOI I)e ] [//H2OI) interlayer to form 

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However, despite the outstanding achievements of evolutionary biochemistry, many problems still await solution. Among these unsolved and relatively little-investigated problems of evolutionary biochemistry, there are the role of phosphorus compounds in chemical evolution, which preceded the appearance of life on Earth, and the evolution of phosphorus metabolism from primitive organisms to contemporary living creatures. 

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