Towards a prebiotic chemoton - nucleotide precursor synthesis driven by the autocatalytic formose reaction

Quoc Phuong Tran; Ruiqin Yi; Albert C Fahrenbach

doi:10.1039/d3sc03185c

Towards a prebiotic chemoton - nucleotide precursor synthesis driven by the autocatalytic formose reaction

Chem Sci. 2023 Aug 29;14(35):9589-9599. doi: 10.1039/d3sc03185c. eCollection 2023 Sep 13.

Authors

Quoc Phuong Tran^{1

2}, Ruiqin Yi³, Albert C Fahrenbach^{1

2

4}

Affiliations

¹ School of Chemistry, University of New South Wales Sydney NSW 2052 Australia a.fahrenbach@unsw.edu.au.
² Australian Centre for Astrobiology, University of New South Wales Sydney NSW 2052 Australia.
³ Earth-Life Science Institute, Tokyo Institute of Technology Tokyo 152-8550 Japan.
⁴ UNSW RNA Institute, University of New South Wales Sydney NSW 2052 Australia.

Abstract

The formose reaction is often cited as a prebiotic source of sugars and remains one of the most plausible forms of autocatalysis on the early Earth. Herein, we investigated how cyanamide and 2-aminooxazole, molecules proposed to be present on early Earth and precursors for nonenzymatic ribonucleotide synthesis, mediate the formose reaction using HPLC, LC-MS and ¹H NMR spectroscopy. Cyanamide was shown to delay the exponential phase of the formose reaction by reacting with formose sugars to form 2-aminooxazole and 2-aminooxazolines thereby diverting some of these sugars from the autocatalytic cycle, which nonetheless remains intact. Masses for tetrose and pentose aminooxazolines, precursors for nucleotide synthesis including TNA and RNA, were also observed. The results of this work in the context of the chemoton model are further discussed. Additionally, we highlight other prebiotically plausible molecules that could have mediated the formose reaction and alternative prebiotic autocatalytic systems.