Ribonucleotídeos: era o que faltava para o mundo RNA

quinta-feira, março 11, 2010

Ribonucleotides

John D. Sutherland

-Author Affiliations
School of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
Corespondence:john.sutherland@manchester.ac.uk

Abstract

It has normally been assumed that ribonucleotides arose on the early Earth through a process in which ribose, the nucleobases, and phosphate became conjoined. However, under plausible prebiotic conditions, condensation of nucleobases with ribose to give β-ribonucleosides is fraught with difficulties. The reaction with purine nucleobases is low-yielding and the reaction with the canonical pyrimidine nucleobases does not work at all. The reasons for these difficulties are considered and an alternative high-yielding synthesis of pyrimidine nucleotides is discussed. Fitting the new synthesis to a plausible geochemical scenario is a remaining challenge but the prospects appear good. Discovery of an improved method of purine synthesis, and an efficient means of stringing activated nucleotides together, will provide underpinning support to those theories that posit a central role for RNA in the origins of life.

Copyright © 2010 Cold Spring Harbor Laboratory Press; all rights reserved

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