1tzf
From Proteopedia
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X-ray Crystal Structure of alpha-D-glucose-1-phosphate cytidylyltransferase from Salmonella typhi
Overview
Dideoxysugars, which display biological activities ranging from mediating, cell-cell interactions to serving as components in some antibiotics, are, synthesized in various organisms via complex biochemical pathways that, begin with the attachment of alpha-D-glucose 1-phosphate to either CTP or, dTTP. Here we describe the three-dimensional structure of the, alpha-D-glucose-1-phosphate cytidylyltransferase from Salmonella typhi, which catalyzes the first step in the production of CDP-tyvelose. For this, investigation, the enzyme was crystallized in the presence of its product, CDP-glucose. In contrast to previous reports, the enzyme exists as a fully, integrated hexamer with 32-point group symmetry. Each subunit displays a, "bird-like" appearance with the "body" composed predominantly of a, seven-stranded mixed beta-sheet and the two "wings" formed by beta-hairpin, motifs. These two wings mediate subunit-subunit interactions along the, 3-fold and 2-fold rotational axes, respectively. The six active sites of, the hexamer are situated between the subunits related by the 2-fold, rotational axes. CDP-glucose is anchored to the protein primarily by, hydrogen bonds with backbone carbonyl oxygens and peptidic NH groups. The, side chains of Arg111 and Asn188 from one subunit and Glu178 and Lys179, from the second subunit are also involved in hydrogen bonding with the, ligand. The topology of the main core domain bears striking similarity to, that observed for glucose-1-phosphate thymidylyltransferase and, 4-diphosphocytidyl-2-C-methylerythritol synthetase.
About this Structure
1TZF is a Single protein structure of sequence from Salmonella typhi with MG and C5G as ligands. Active as Glucose-1-phosphate cytidylyltransferase, with EC number 2.7.7.33 Full crystallographic information is available from OCA.
Reference
Molecular structure of alpha-D-glucose-1-phosphate cytidylyltransferase from Salmonella typhi., Koropatkin NM, Holden HM, J Biol Chem. 2004 Oct 15;279(42):44023-9. Epub 2004 Aug 3. PMID:15292268
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