Essential role of an active-site guanine in glmS ribozyme catalysis.

Journal of the American Chemical Society

PubMedID: 17990888

Klein DJ, Been MD, Ferré-D'Amaré AR. Essential role of an active-site guanine in glmS ribozyme catalysis. J Am Chem Soc. 2007;129(48):14858-9.
The glmS ribozyme is a catalytic riboswitch that is activated for endonucleolytic cleavage by the coenzyme glucosamine-6-phosphate. Using kinetic assays and X-ray crystallography, we identify an active-site mutation of a conserved guanine that abolishes catalysis without perturbing coenzyme binding. Our results provide evidence that coenzyme function requires a specific nucleobase to interact with the nucleophile of the cleavage reaction.