Publications

• Enzymatic synthesis of deoxypseudouridylic acid and a study of certain of its properties.

  Remsen J.F., Matsushita T., Chirikjian J.G., Davis F.F.

  Biochim Biophys Acta 281:481-487(1972) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Molecular identification of pseudouridine-metabolizing enzymes.

  Preumont A., Snoussi K., Stroobant V., Collet J.-F., Van Schaftingen E.

  Pseudouridine, a non-classical nucleoside present in human urine as a degradation product of RNAs, is one of the few molecules that has a glycosidic C-C bond. Through a data base mining approach involving transcriptomic data, we have molecularly identified two enzymes that are involved in the meta ... >> More

  Pseudouridine, a non-classical nucleoside present in human urine as a degradation product of RNAs, is one of the few molecules that has a glycosidic C-C bond. Through a data base mining approach involving transcriptomic data, we have molecularly identified two enzymes that are involved in the metabolism of pseudouridine in uropathogenic Escherichia coli, the principal agent of urinary tract infections in humans. The first enzyme, coded by the gene yeiC, specifically phosphorylates pseudouridine to pseudouridine 5'-phosphate. Accordingly, yeiC(-) mutants are unable to metabolize pseudouridine, in contrast to wild-type E. coli UTI89. The second enzyme, encoded by the gene yeiN belonging to the same operon as yeiC, catalyzes the conversion of pseudouridine 5'-phosphate to uracil and ribose 5-phosphate in a divalent cation-dependent manner. Remarkably, the glycosidic C-C bond of pseudouridine is cleaved in the course of this reaction, indicating that YeiN is the first molecularly identified enzyme able to hydrolyze a glycosidic C-C bond. Though this reaction is easily reversible, the association of YeiN with pseudouridine kinase indicates that it serves physiologically to metabolize pseudouridine 5'-phosphate rather than to form it. YeiN is homologous to Thermotoga maritima IndA, a protein with a new fold, which we now show to act also as a pseudouridine-5'-phosphate glycosidase. Data base mining indicates that most eukaryotes possess homologues of pseudouridine kinase and pseudouridine-5'-phosphate glycosidase and that these are most often associated in a single bifunctional protein. The gene encoding this bifunctional protein is absent from the genomes of man and other mammals, indicating that the capacity for metabolizing pseudouridine has been lost late in evolution. << Less

  J. Biol. Chem. 283:25238-25246(2008) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.

• Pseudouridine monophosphate glycosidase: a new glycosidase mechanism.

  Huang S., Mahanta N., Begley T.P., Ealick S.E.

  Pseudouridine (Ψ), the most abundant modification in RNA, is synthesized in situ using Ψ synthase. Recently, a pathway for the degradation of Ψ was described [Preumont, A., Snoussi, K., Stroobant, V., Collet, J. F., and Van Schaftingen, E. (2008) J. Biol. Chem. 283, 25238-25246]. In this pathway, ... >> More

  Pseudouridine (Ψ), the most abundant modification in RNA, is synthesized in situ using Ψ synthase. Recently, a pathway for the degradation of Ψ was described [Preumont, A., Snoussi, K., Stroobant, V., Collet, J. F., and Van Schaftingen, E. (2008) J. Biol. Chem. 283, 25238-25246]. In this pathway, Ψ is first converted to Ψ 5'-monophosphate (ΨMP) by Ψ kinase and then ΨMP is degraded by ΨMP glycosidase to uracil and ribose 5-phosphate. ΨMP glycosidase is the first example of a mechanistically characterized enzyme that cleaves a C-C glycosidic bond. Here we report X-ray crystal structures of Escherichia coli ΨMP glycosidase and a complex of the K166A mutant with ΨMP. We also report the structures of a ring-opened ribose 5-phosphate adduct and a ring-opened ribose ΨMP adduct. These structures provide four snapshots along the reaction coordinate. The structural studies suggested that the reaction utilizes a Lys166 adduct during catalysis. Biochemical and mass spectrometry data further confirmed the existence of a lysine adduct. We used site-directed mutagenesis combined with kinetic analysis to identify roles for specific active site residues. Together, these data suggest that ΨMP glycosidase catalyzes the cleavage of the C-C glycosidic bond through a novel ribose ring-opening mechanism. << Less

  Biochemistry 51:9245-9255(2012) [PubMed] [EuropePMC]