Essential role of an active-site guanine in glmS ribozyme catalysis.
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.
Klein
Daniel J
DJ
Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, Seattle, Washington 98109, USA.
Been
Michael D
MD
Ferré-D'Amaré
Adrian R
AR
D001408:Bacillus anthracis / Q000201:enzymology / Q000235:genetics; D001665:Binding Sites; D002384:Catalysis; D018360:Crystallography, X-Ray; D006147:Guanine / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D015394:Molecular Structure; D009154:Mutation / Q000235:genetics; D016337:RNA, Catalytic / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D046968:Thermoanaerobacter / Q000201:enzymology / Q000235:genetics
D016337:RNA, Catalytic; D006147:Guanine