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Two crystal structures of dihydrofolate reductase-thymidylate synthase from Cryptosporidium hominis reveal protein-ligand interactions including a structural basis for observed antifolate resistance.

ABSTRACT: Cryptosporidium hominis is a protozoan parasite that causes acute gastrointestinal illness. There are no effective therapies for cryptosporidiosis, highlighting the need for new drug-lead discovery. An analysis of the protein-ligand interactions in two crystal structures of dihydrofolate reductase-thymidylate synthase (DHFR-TS) from C. hominis, determined at 2.8 and 2.87 A resolution, reveals that the interactions of residues Ile29, Thr58 and Cys113 in the active site of C. hominis DHFR provide a possible structural basis for the observed antifolate resistance. A comparison with the structure of human DHFR reveals active-site differences that may be exploited for the design of species-selective inhibitors.

SUBMITTER: Anderson AC

PROVIDER: S-EPMC1952288 | biostudies-literature | 2005 Mar

REPOSITORIES: biostudies-literature

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Two crystal structures of dihydrofolate reductase-thymidylate synthase from Cryptosporidium hominis reveal protein-ligand interactions including a structural basis for observed antifolate resistance.

Anderson Amy C AC

Acta crystallographica. Section F, Structural biology and crystallization communications 20050208 Pt 3

Cryptosporidium hominis is a protozoan parasite that causes acute gastrointestinal illness. There are no effective therapies for cryptosporidiosis, highlighting the need for new drug-lead discovery. An analysis of the protein-ligand interactions in two crystal structures of dihydrofolate reductase-thymidylate synthase (DHFR-TS) from C. hominis, determined at 2.8 and 2.87 A resolution, reveals that the interactions of residues Ile29, Thr58 and Cys113 in the active site of C. hominis DHFR provide ...[more]

PMID: 16511011

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Structural studies provide clues for analog design of specific inhibitors of Cryptosporidium hominis thymidylate synthase-dihydrofolate reductase.

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