Publications by authors named "Celia J Webby"

Lysyl and prolyl hydroxylations are well-known post-translational modifications to animal and plant proteins with extracellular roles. More recent work has indicated that the hydroxylation of intracellular animal proteins may be common. JMJD6 catalyses the iron- and 2-oxoglutarate-dependent hydroxylation of lysyl residues in arginine-serine-rich domains of RNA splicing-related proteins.

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The shikimate pathway, responsible for aromatic amino acid biosynthesis, is required for the growth of Mycobacterium tuberculosis and is a potential drug target. The first reaction is catalyzed by 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase (DAH7PS). Feedback regulation of DAH7PS activity by aromatic amino acids controls shikimate pathway flux.

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The finding that the metazoan hypoxic response is regulated by oxygen-dependent posttranslational hydroxylations, which regulate the activity and lifetime of hypoxia-inducible factor (HIF), has raised the question of whether other hydroxylases are involved in the regulation of gene expression. We reveal that the splicing factor U2 small nuclear ribonucleoprotein auxiliary factor 65-kilodalton subunit (U2AF65) undergoes posttranslational lysyl-5-hydroxylation catalyzed by the Fe(II) and 2-oxoglutarate-dependent dioxygenase Jumonji domain-6 protein (Jmjd6). Jmjd6 is a nuclear protein that has an important role in vertebrate development and is a human homolog of the HIF asparaginyl-hydroxylase.

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Variants in the FTO (fat mass and obesity associated) gene are associated with increased body mass index in humans. Here, we show by bioinformatics analysis that FTO shares sequence motifs with Fe(II)- and 2-oxoglutarate-dependent oxygenases. We find that recombinant murine Fto catalyzes the Fe(II)- and 2OG-dependent demethylation of 3-methylthymine in single-stranded DNA, with concomitant production of succinate, formaldehyde, and carbon dioxide.

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The enzymes of the shikimate pathway are attractive targets for new-generation antimicrobial agents. The first step of this pathway is catalysed by 3-deoxy-D-arabino-heptulosonate-7-phosphate (DAH7P) synthase and involves the condensation of phosphoenolpyruvate (PEP) and erythrose 4-phosphate (E4P) to form DAH7P. DAH7P synthases have been classified into two apparently evolutionarily unrelated types and whereas structural data have been obtained for the type I DAH7P synthases, no structural information is available for their type II counterparts.

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The shikimate pathway, responsible for the biosynthesis of aromatic compounds, is essential for the growth of Mycobacterium tuberculosis and is a potential target for the design of new anti-tuberculosis drugs. The first step of this pathway is catalyzed by 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase (DAH7PS). The DAH7PSs have been classified into two apparently unrelated types and, whereas structural data have been obtained for the type I DAH7PSs, no structural information is available for their type II counterparts.

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DAH7P (3-Deoxy-D-arabino-heptulosonate 7-phosphate) synthase catalyses the condensation reaction between phosphoenolpyruvate (PEP) and D-erythrose 4-phosphate (E4P) as the first committed step in the biosynthesis of aromatic compounds in plants and micro-organisms. Previous work has identified two families of DAH7P synthases based on sequence similarity and molecular mass, with the majority of the mechanistic and structural studies being carried out on the type I paralogues from Escherichia coli. Whereas a number of organisms possess genes encoding both type I and type II DAH7P synthases, the pathogen Helicobacter pylori has only a single, type II, enzyme.

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