Publications by authors named "Corinne Nguyen"

We have previously identified a series of triphenylmethane derivatives of deoxyuridine with antimalarial activity in vitro which selectively inhibit Plasmodium falciparum deoxyuridine triphosphate nucleotidohydrolase (PfdUTPase) compared to the human enzyme. The crystal structure of PfdUTPase in complex with one of these inhibitors suggested that the triphenylmethane derivative was selective due to a series of interactions between the trityl group and the side chains of residues Phe(46), Ile(117) and Lys(96) located in a hydrophobic pocket distinct from the phosphate binding site. Here we show by site-directed mutagenesis that the hydrophobic nature of the trityl binding site and in particular aromatic interactions established between the inhibitor and residue Phe(46) contribute significantly to the binding of uracil-based derivatives containing trityl groups in the 5'-position.

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2'-Deoxyuridine triphosphate nucleotidohydrolase (dUTPase) is a potential drug target for the treatment of malaria. We previously reported the discovery of 5'-tritylated analogues of deoxyuridine as selective inhibitors of this Plasmodium falciparum enzyme. Herein we report further structure-activity studies; in particular, variations of the 5'-trityl group, the introduction of various substituents at the 3'-position of deoxyuridine, and modifications of the base.

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The enzyme deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) catalyses the hydrolysis of dUTP to dUMP and PPi thus controlling the incorporation of uracil into DNA genomes. In Campylobacter jejuni dUTPase exhibits structural properties of dimeric proteins characteristic of protozoa of the Kinetoplastidae family. In the present study we perform a kinetic analysis of Campylobacter dUTPase using the continuous spectrophotometric method and show that the enzyme is highly specific for deoxyuridine nucleotides.

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We report the discovery of novel uracil-based acyclic compounds as inhibitors of deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase), an enzyme involved in nucleotide metabolism that has been identified as a promising target for the development of antimalarial drugs. Compounds were assayed against both P.falciparum dUTPase and intact parasites.

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This paper describes a structure-activity study to identify novel, small-molecule inhibitors of the enzyme deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) from parasitic protozoa. The successful synthesis of a variety of analogues of dUMP is described in which the substituents are introduced at the 3'- and 5'-positions, together with variation in the heteroatom at the 5'-position. The compounds were assayed against recombinant Plasmodium falciparum and Leishmania major enzymes and the human enzyme to give a measure of selectivity.

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Pyrimidine metabolism is a major route for therapeutic intervention against malaria. Here we report inhibition and structural studies on the deoxyuridine nucleotidohydrolase from the malaria parasite Plasmodium falciparum (PfdUTPase). We have identified a series of triphenylmethane derivatives of deoxyuridine with antimalarial activity in vitro which inhibit specifically the Plasmodium dUTPase versus the human enzyme.

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