Non‐Enzymatic Synthesis of Polysaccharides, Nucleosides and Nucleic Acids and the Origin of Self‐Reproducing Systems

Abstract

Compounds containing free amino, hydroxyl or carbonyl groups can be activated by reaction with polyphosphate ester. tf the compoundc; contain a second functional group, polyconden-sations are possible; e.g. amino acids + polypeptides, carbohydrates + polysaccharides, nucleotides + polynucleotides. In the presence of polyadenylic acid, polymerization of uridylic acid is speeded up tenfold. This mutual efect of complementary nucleotide strands constitutes the experimental basis for a hypothesis concerning the terrestrial origin of systems capable of self reproduction.

Biology and the Exploration of Mars

“…As already stated, coding function has been claimed for synthetic polymers of mononucleotides (Matthei by Schramm in Schramm [1964]). …”

“…Polynucleotides of limited size have been produced from mononucleotides and ethyl metaphosphate (an unnatural reagent) [Schramm, 1964], and from polyphosphoric acid and cytidylic acid [Schwartz and Fox, 1964]. Further study seems more likely to yield larger synthetic macromolecules than to yield a surer criterion based on the polynucleotide structure.…”

“…Further study seems more likely to yield larger synthetic macromolecules than to yield a surer criterion based on the polynucleotide structure. Coding ability has been claimed for the synthetic polynucleotide [Schramm, 1964]. Whereas the origin of the necessary mononuc1eotides has not been shown comprehensively, the fact that adenosine mono-and triphosphate AMP and ATP can be produced [Ponnamperuma, 1964] suggests the likelihood of similar possibilities for the monophosphates of guanine, cytosine and uracil.…”

Fast tidal cycling and the origin of life

“…Concentrations of polymer precursors in the primordial soup (Oparin, 1957;Miller, 1953;Miller and Urey, 1959), possibly including phosphate-activated nucleosides (Gulick, 1955;Schramm et al, 1962), were limiting (Hull, 1960;Bernal, 1960). Alignment of precursors opposite a parental strand is favored by high precursor concentrations, during the drying phase, and impaired at low concentrations, during dilution.…”

“…In vitro, under conditions intended to resemble the early terrestrial surface, non-enzymatic polymerization of amino acids or nucleotides can take place (Fox and Harada, 1958;Schramm et al, 1962;Naylor and Gilham, 1966;von Kiedrowski et al, 1989;Ferris et al, 1996;Li and Nicolaou, 2002;Luther et al, 1998). A favored scenario is that one polymer strand directed the synthesis of a complementary strand, as in modern DNA.…”