1z6b
From Proteopedia
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Crystal structure of Plasmodium falciparum FabZ at 2.1 A
Overview
The unique beta-hydroxyacyl-ACP dehydratase in Plasmodium falciparum, PfFabZ, is involved in fatty acid biosynthesis and catalyzes the, dehydration of beta-hydroxy fatty acids linked to acyl carrier protein., The structure was solved by single anomalous dispersion (SAD) phasing, using a quick-soaking experiment with potassium iodide and refined to a, resolution of 2.1 A. The crystal structure represents the first structure, of a Plasmodium beta-hydroxyacyl-ACP dehydratase with broad substrate, specificity. The asymmetric unit contains a hexamer that appears as a, trimer of dimers. Each dimer shows the known "hot dog" fold that has been, observed in only a few other protein structures. Each of the two, independent active sites in the dimer is formed by equal contributions, from both subunits. The active site is mainly hydrophobic and looks like, an L-shaped tunnel. The catalytically important amino acids His 133 and, Glu 147' (from the other subunit), together with His98', form the only, hydrophilic site in this tunnel. The inner end of the active site tunnel, is closed by the phenyl ring of Phe 169, which is located in a flexible, partly visible loop. In order to explain the acceptance of substrates, longer than ~C-7, the phenyl ring must move away to open the tunnel. The, present structure supports an enzymatic mechanism consisting of an, elimination reaction catalyzed by His 133 and Glu147'., 3-decynoyl-N-acetylcysteamine, an inhibitor known to interact with the E., coli dehydratase/isomerase, turned out to interact covalently with PfFabZ., A first model of PfFabZ with this potent inhibitor is presented.
About this Structure
1Z6B is a Single protein structure of sequence from Plasmodium falciparum with CL, CAC and SO4 as ligands. Full crystallographic information is available from OCA.
Reference
The crystal structure of PfFabZ, the unique beta-hydroxyacyl-ACP dehydratase involved in fatty acid biosynthesis of Plasmodium falciparum., Kostrewa D, Winkler FK, Folkers G, Scapozza L, Perozzo R, Protein Sci. 2005 Jun;14(6):1570-80. PMID:15930004
Page seeded by OCA on Sun Nov 25 04:45:22 2007
