EC Number   |
|---|
    3.2.1.37 | - |
| 3.2.1.37 | both D-xylose-bound enzyme and a covalent 2-deoxy-2-fluoro-alpha-D-xylosyl-enzyme intermediate complex |
| 3.2.1.37 | hanging-drop vapor-diffusion method at 10°C, crystal structures of the enzyme in the unliganded form and with bound products, at 1.7 A resolution. The structures are very similar to those of other enzymes belonging to glycoside hydrolase family 43. The monosaccharides are bound in very different ways. Arabinose preferentially binds in subsite -1, while xylose exclusively interacts with subsite +1 |
| 3.2.1.37 | homology modeling of structure |
| 3.2.1.37 | in complex with substrate xylobiose. The xylose moiety at the K1 subsite is held by a large number of hydrogen bonds, whereas only one hydroxyl of the xylose unit at the C1 subsite can create hydrogen bonds with the enzyme. The general base, Asp15, is located on the alpha-side of the K1 xylose sugar ring, 5.2 A from the anomeric carbon. This location enables it to activate a water molecule for a single displacement attack on the anomeric carbon, resulting in inversion of the anomeric configuration. Glu187, the general acid, is 2.4 A from the glycosidic oxygen atom and can protonate the leaving aglycon. The third catalytic carboxylic acid, Asp128, is 4 A from the general acid, modulating its pKa and keeping it in the correct orientation relative to the substrate |
| 3.2.1.37 | molecular docking studies for the enzyme with the substrates xylobiose and 4-nitrophenyl-beta-D-xylopyranoside. The essential catalytic residues of RuBG3A are D297 and E499. Besides D113, K218, H219, and R185 also form hydrogen bonds with substrates and are condervative. The active center for beta-glucosidic and beta-xylosidic substrates are the same and the bifunctional activity should come from one functional domain. RuBG3A and RuBG3B exhibit higher scores in the docking analysis against 4-nitrophenyl-beta-D-glucopyranoside than against 4-nitrophenyl-beta-D-xylopyranoside, indicating a larger affinity between the enzymes and 4-nitrophenyl-beta-D-glucopyranoside, which is consistent with the kinetic parameters |
| 3.2.1.37 | molecular docking studies for the enzyme with the substrates xylobiose and 4-nitrophenyl-beta-D-xylopyranoside. The essential catalytic residues of RuBG3B are D272 and E481. Besides D88, K193, H194, and R160 also form hydrogen bonds with substrates and are condervative. The active center for beta-glucosidic and beta-xylosidic substrates are the same and the bifunctional activity should come from one functional domain. RuBG3A and RuBG3B exhibit higher scores in the docking analysis against 4-nitrophenyl-beta-D-glucopyranoside than against 4-nitrophenyl-beta-D-xylopyranoside, indicating a larger affinity between the enzymes and 4-nitrophenyl-beta-D-glucopyranoside, which is consistent with the kinetic parameters |
| 3.2.1.37 | native enzyme and selenomethionyl derivative |
| 3.2.1.37 | purified recombinant enzyme, hanging drop vapour diffusion method, 0.002 ml protein solution containing 5 mg/ml protein in 50 mM Tris-HCl, pH 7.0, 100 mM NaCl, and 0.02% NaN3, is mixed with 0.002 ml well solution containing 2.3-2.4 M ammonium sulfate, and 40-60 mM sodium citrate at pH 5.5, a few weeks, X-ray diffraction structure determination and analysis at 2.0 A resolution |
| 3.2.1.37 | purified recombinant wild-type and mutant D15G, D128G, and E178G XynB3s, 22-30 mg/ml protein, 0.005 ml protein solution is mixed with 0.005 ml reservoir solution and 0.001 ml detergent solution, equilibration to 0.5 ml with reservoir solution, X-ray diffraction structure determination and preliminary analysis at 2.2-2.5 A resolution |
