|Title||RNA with iron(II) as a cofactor catalyses electron transfer.|
|Publication Type||Journal Article|
|Year of Publication||2013|
|Authors||Hsiao, C, Chou, I-C, C Okafor, D, Bowman, JC, O'Neill, EB, Athavale, SS, Petrov, AS, Hud, NV, Wartell, RM, Harvey, SC, Williams, LDean|
|Date Published||2013 Jun|
|Keywords||Biocatalysis, Electron Transport, Iron, RNA|
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.
|Alternate Journal||Nat Chem|