Reaction of Woodward's reagent K with d -xylose isomerases. Modification of an active site carboxylate residue
| Autor: | C. K. de Bruyne, Hilda Kersters-Hilderson, M Callens, W Vangrysperre |
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| Rok vydání: | 1989 |
| Předmět: |
Xylose isomerase
Stereochemistry Isomerase Ligands Biochemistry chemistry.chemical_compound Carboxylate Oxazoles Molecular Biology Aldose-Ketose Isomerases Binding Sites biology Lactobacillus brevis Chemical modification Active site Isoxazoles Cell Biology biology.organism_classification Kinetics chemistry Reagent biology.protein Indicators and Reagents Bacillus coagulans Carbohydrate Epimerases Research Article |
| Zdroj: | Biochemical Journal. 260:163-169 |
| ISSN: | 1470-8728 0264-6021 |
| DOI: | 10.1042/bj2600163 |
| Popis: | D-Xylose isomerases from Streptomyces violaceoruber, Streptomyces sp., Lactobacillus xylosus, Lactobacillus brevis and Bacillus coagulans were rapidly inactivated by Woodward's reagent K. Second-order rate constants in the absence of ligands, at pH 6.0 and 25 degrees C, were 41, 36, 22, 95 and 26 M-1.min-1 respectively. Spectral analysis at 340 nm revealed that inactivation was correlated with modification of five, six, two, three and six carboxylate residues per monomer respectively. In the presence of protecting ligands, modification of one carboxylate group was prevented. The results support the idea of an active site glutamate or aspartate group that may contribute to the catalytic activity of all these D-xylose isomerases. |
| Databáze: | OpenAIRE |
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