Séminaire IBS : Reflections on the origin of biocatalysis

Par Dr Juan-Carlos Fontecilla-Camps (IBS/Groupe Métalloprotéines)

The principle of continuity posits that some primordial biocatalytic mechanisms should still be present in the protein synthesis pathway. Key biomolecular reactions of this process are catalyzed by DNA-dependent RNA polymerases, aminoacyl-tRNA synthetases, and ribosomes. Remarkably, none of these biocatalysts contribute chemically active groups to their respective reactions. Instead, structural and functional studies have demonstrated that they resort to “substrate-assisted” catalysis and a binding mode described as an “entropy trap”. These reactions are stereochemically and mechanistically simpler than the ones found in most modern enzymes and are consistent with the way in which primordial catalysts could have operated.