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Spontaneous formation and base pairing of plausible prebiotic nucleotides in water

Brian J. Cafferty, David M. Fialho, Jaheda Khanam, Ramanarayanan Krishnamurthy & Nicholas V. Hud

Affiliations Contributions Corresponding author

Nature Communications 7, Article number: 11328 doi:10.1038/ncomms11328

Received 02 August 2015 Accepted 16 March 2016 Published 25 April 2016



Abstract

The RNA World hypothesis presupposes that abiotic reactions originally produced nucleotides, the monomers of RNA and universal constituents of metabolism. However, compatible prebiotic reactions for the synthesis of complementary (that is, base pairing) nucleotides and mechanisms for their mutual selection within a complex chemical environment have not been reported. Here we show that two plausible prebiotic heterocycles, melamine and barbituric acid, form glycosidic linkages with ribose and ribose-5-phosphate in water to produce nucleosides and nucleotides in good yields. Even without purification, these nucleotides base pair in aqueous solution to create linear supramolecular assemblies containing thousands of ordered nucleotides. Nucleotide anomerization and supramolecular assemblies favour the biologically relevant β-anomer form of these ribonucleotides, revealing abiotic mechanisms by which nucleotide structure and configuration could have been originally favoured. These findings indicate that nucleotide formation and selection may have been robust processes on the prebiotic Earth, if other nucleobases preceded those of extant life.

Subject terms: Chemical sciences Organic chemistry Chemical biology

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