title: The products of 5-fluorouridine by the action of the pseudouridine synthase TruB disfavor one mechanism and suggest another.
abstract: The pseudouridine synthase TruB handles 5-fluorouridine in RNA as a substrate, converting it into two isomeric hydrated products. Unexpectedly, the two products differ not in the hydrated pyrimidine ring but in the pentose ring, which is epimerized to arabinose in the minor product. This inversion of stereochemistry at C2' suggests that pseudouridine generation may proceed by a mechanism involving a glycal intermediate or that the previously proposed mechanism involving an acylal intermediate operates but with an added reaction manifold for 5-fluorouridine versus uridine. The arabino product strongly disfavors a mechanism involving a Michael addition to the pyrimidine ring.
authors: Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
authors: Edward J
authors: EJ
authors: Miracco
authors: Eugene G
authors: EG
authors: Mueller
mesh_terms: D019751:Intramolecular Transferases / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D011789:Quantum Theory; D012313:RNA / Q000737:chemistry / Q000378:metabolism; D013237:Stereoisomerism; D014529:Uridine / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000737:chemistry
chemical_list: C001943:5-fluorouridine; D012313:RNA; D019751:Intramolecular Transferases; C096995:pseudouridine synthases; D014529:Uridine