Human -editing enzyme displays tRNA acceptor-stem specificity and relaxed amino acid selectivity.

Accurate translation of genetic information into proteins is vital for cell sustainability. ProXp-ala prevents proteome-wide Pro-to-Ala mutations by hydrolyzing misacylated Ala-tRNA, which is synthesized by prolyl-tRNA synthetase. Bacterial ProXp-ala was previously shown to combine a size-based exclusion mechanism with conformational and chemical selection for the recognition of the alanyl moiety, whereas tRNA is selected via recognition of tRNA acceptor-stem elements G72 and A73.