RNA with iron(II) as a cofactor catalyses electron transfer.

TitleRNA with iron(II) as a cofactor catalyses electron transfer.
Publication TypeJournal Article
Year of Publication2013
AuthorsHsiao, C, Chou, I-C, C Okafor, D, Bowman, JC, O'Neill, EB, Athavale, SS, Petrov, AS, Hud, NV, Wartell, RM, Harvey, SC, Williams, LDean
JournalNat Chem
Volume5
Issue6
Pagination525-8
Date Published2013 Jun
ISSN1755-4349
KeywordsBiocatalysis, Electron Transport, Iron, RNA
Abstract

Mg(2+) is essential for RNA folding and catalysis. However, for the first 1.5 billion years of life on Earth RNA inhabited an anoxic Earth with abundant and benign Fe(2+). We hypothesize that Fe(2+) was an RNA cofactor when iron was abundant, and was substantially replaced by Mg(2+) during a period known as the 'great oxidation', brought on by photosynthesis. Here, we demonstrate that reversing this putative metal substitution in an anoxic environment, by removing Mg(2+) and replacing it with Fe(2+), expands the catalytic repertoire of RNA. Fe(2+) can confer on some RNAs a previously uncharacterized ability to catalyse single-electron transfer. We propose that RNA function, in analogy with protein function, can be understood fully only in the context of association with a range of possible metals. The catalysis of electron transfer, requisite for metabolic activity, may have been attenuated in RNA by photosynthesis and the rise of O2.

DOI10.1038/nchem.1649
Alternate JournalNat Chem
PubMed ID23695635