2h6e
From Proteopedia
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Crystal structure of the D-arabinose dehydrogenase from Sulfolobus solfataricus
Overview
Sulfolobus solfataricus metabolizes the five-carbon sugar d-arabinose to, 2-oxoglutarate by an inducible pathway consisting of dehydrogenases and, dehydratases. Here we report the crystal structure and biochemical, properties of the first enzyme of this pathway: the d-arabinose, dehydrogenase. The AraDH structure was solved to a resolution of 1.80 A by, single-wavelength anomalous diffraction and phased using the two, endogenous zinc ions per subunit. The structure revealed a catalytic and, cofactor binding domain, typically present in mesophilic and thermophilic, alcohol dehydrogenases. Cofactor modeling showed the presence of a, phosphate binding pocket sequence motif (SRS-X(2)-H), which is likely to, be responsible for the enzyme's preference for NADP(+). The, homo-tetrameric enzyme is specific for d-arabinose, l-fucose, l-galactose, and d-ribose, which could be explained by the hydrogen bonding patterns of, the C3 and C4 hydroxyl groups observed in substrate docking simulations., The enzyme optimally converts sugars at pH 8.2 and 91 degrees C, and, displays a half-life of 42 and 26 min at 85 and 90 degrees C, respectively, indicating that the enzyme is thermostable at physiological, operating temperatures of 80 degrees C. The structure represents the first, crystal structure of an NADP(+)-dependent member of the medium-chain, dehydrogenase/reductase (MDR) superfamily from Archaea.
About this Structure
2H6E is a Single protein structure of sequence from Sulfolobus solfataricus with as ligand. Active as D-arabinose 1-dehydrogenase (NAD(P)(+)), with EC number 1.1.1.117 Full crystallographic information is available from OCA.
Reference
Crystal Structure and Biochemical Properties of the d-Arabinose Dehydrogenase from Sulfolobus solfataricus., Brouns SJ, Turnbull AP, Willemen HL, Akerboom J, van der Oost J, J Mol Biol. 2007 Aug 31;371(5):1249-60. Epub 2007 Jun 8. PMID:17610898
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