Open AccessThe Pseudouridine Synthases Proceed through a Glycal Intermediate
Author(s) -
Govardhan Reddy Veerareddygari,
Sanjay K. Singh,
Eugene G. Mueller
Publication year - 2016
Publication title -
journal of the american chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.115
H-Index - 612
eISSN - 1520-5126
pISSN - 0002-7863
DOI - 10.1021/jacs.6b04491
Subject(s) - chemistry , pseudouridine , deprotonation , glycal , stereochemistry , kinetic isotope effect , isomerization , deuterium , rna , organic chemistry , biochemistry , stereoselectivity , catalysis , transfer rna , ion , physics , quantum mechanics , gene
The pseudouridine synthases isomerize (U) in RNA to pseudouridine (Ψ), and the mechanism that they follow has long been a question of interest. The recent elucidation of a product of the mechanistic probe 5-fluorouridine that had been epimerized to the arabino isomer suggested that the Ψ synthases might operate through a glycal intermediate formed by deprotonation of C2'. When that position in substrate U is deuterated, a primary kinetic isotope effect is observed, which indisputably indicates that the proposed deprotonation occurs during the isomerization of U to Ψ and establishes the mechanism followed by the Ψ synthases.