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http://purl.uniprot.org/citations/8180169http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/8180169http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/8180169http://www.w3.org/2000/01/rdf-schema#comment"The X-ray crystallographic structures of the metal-activated enzyme xylose isomerase from Streptomyces olivochromogenes with the substrates D-glucose, 3-O-methyl-D-glucose and in the absence of substrate were determined to 1.96-, 2.19-, and 1.81-A resolution and refined to R-factors of 16.6%, 15.9%, and 16.1%, respectively. Xylose isomerase catalyzes the interconversion between glucose and fructose (xylose and xylulose under physiological conditions) by utilizing two metal cofactors to promote a hydride shift; the metals are bridged by a glutamate residue. This puts xylose isomerase in the small but rapidly growing family of enzymes with a bridged bimetallic active site, in which both metals are involved in the chemical transformation. The substrate 3-O-methylglucose was chosen in order to position the glucose molecule in the observed electron density unambiguously. Of the two essential magnesium ions per active site, Mg-2 was observed to occupy two alternate positions, separated by 1.8 A, in the substrate-soaked structures. The deduced movement was not observed in the structure without substrate present and is attributed to a step following substrate binding but prior to isomerization. The substrates glucose and 3-O-methylglucose are observed in their linear extended forms and make identical interactions with the enzyme by forming ligands to Mg-1 through O2 and O4 and by forming hydrogen bonds with His53 through O5 and Lys182 through O1. Mg-2 has a water ligand that is interpreted in the crystal structure in the absence of substrate as a hydroxide ion and in the presence of substrate as a water molecule. This hydroxide ion may act as a base to deprotonate the glucose O2 and subsequently protonate the product fructose O1 concomitant with hydride transfer. Calculations of the solvent-accessible surface of possible dimers, with and without the alpha-helical C-terminal domain, suggest that the tetramer is the active form of this xylose isomerase."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.org/dc/terms/identifier"doi:10.1021/bi00184a016"xsd:string
http://purl.uniprot.org/citations/8180169http://purl.org/dc/terms/identifier"doi:10.1021/bi00184a016"xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/author"Lavie A."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/author"Lavie A."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/author"Petsko G.A."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/author"Petsko G.A."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/author"Ringe D."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/author"Ringe D."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/author"Allen K."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/author"Allen K."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/date"1994"xsd:gYear
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/date"1994"xsd:gYear
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/name"Biochemistry"xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/name"Biochemistry"xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/pages"5469-5480"xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/pages"5469-5480"xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/title"X-ray crystallographic structures of D-xylose isomerase-substrate complexes position the substrate and provide evidence for metal movement during catalysis."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/title"X-ray crystallographic structures of D-xylose isomerase-substrate complexes position the substrate and provide evidence for metal movement during catalysis."xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/volume"33"xsd:string
http://purl.uniprot.org/citations/8180169http://purl.uniprot.org/core/volume"33"xsd:string
http://purl.uniprot.org/citations/8180169http://www.w3.org/2004/02/skos/core#exactMatchhttp://purl.uniprot.org/pubmed/8180169
http://purl.uniprot.org/citations/8180169http://www.w3.org/2004/02/skos/core#exactMatchhttp://purl.uniprot.org/pubmed/8180169
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