EC Number   |
|---|
    3.1.3.8 | - |
| 3.1.3.8 | analysis of crystal structure of the phytate complex of Escherichia coli phytase at pH 6.6 with phytate bound via its 3-phosphate to the active site with Hg2+ as intermolecular bridge, X-ray diffraction structure at 2.28 A resolution, analysis of active site loops, overview |
| 3.1.3.8 | apo-enzyme, to 1.9 A resolution, and in complex with substrate analogue myo-inositiol hexakissulfate, to 1.59 A resolution. The substrate analogue is coordinated by residues Arg18, His19, Arg22, Thr25, Lys26, His128, Thr219, His306, Asp307 and a number of water molecules. The Nepsilon2 atom of the catalytic nucleophile, His19, lies 3.2 A from S6 of the analogue and is in-line with the S-O bond from the inositol ring. The OD1 atom of Asp307, the proton donor, forms an H-bond with the oxygen at position 6 of the inositol ring |
| 3.1.3.8 | crystal structure at resolution higher than 1.7 A, native enzyme and enzyme in complex with P=4 at pH 5.5 and at pH 7.5. The enzyme may be a 3-phytase, EC 3.1.3.8, or a 6-phytase, EC 3.1.3.26. The product of the hydrolysis of myo-inositol hexakisphosphate i.e. myo-inositol 1,2,3,4,5-pentakisphosphate or myo-inositol 1,3,4,5,6-pentakisphosphate has not been identified |
| 3.1.3.8 | deglycosylated PhyA free or in complex with inhibitor myo-inositol-1,2,3,4,5,6-hexakis sulfate, vapour-diffusion hanging drop technique, reservoirs contain 1 ml of PEG 3350 at 15-30% w/v, and ammonium nitrate a t0.1-0.4 M, siliconized coverslips are used to suspend a drop containing 0.002 ml of phytase at 13 mg/ml protein concetration and 0.002 ml of reservoir solution over the reservoir, X-ray diffraction structure determination and analysis at 2.2-2.4 A resolution |
| 3.1.3.8 | hanging-drop vapour diffusion method at 22°C, crystal structure determined at 1.5 A resolution. The crystal structure clearly shows a partially occupied phosphohistidine residue, the transient reaction intermediate of the enzyme, at the active site |
| 3.1.3.8 | in complex with phosphate, to 1.9 A resolution |
| 3.1.3.8 | molecular dynamics simulation and comparison between wild-type and thermostable mutant A35E/P42S/Q168R/T248R show that among secondary structure elements, loops have the most impact on the thermal stability of Aspergillus niger phytase. In addition, the location rather than the number of hydrogen bonds has an important contribution to thermostability. Salt bridges may have stabilizing or destabilizing effect on the enzyme and influence its thermostability accordingly |
| 3.1.3.8 | molecular modeling of structure |
| 3.1.3.8 | native PhyK and inactive mutant H25A phytase PhyK, the latter with bound sulfate ions, hanging-drop vapor diffusion at 18°C, 5-6 weeks, for the wild-type enzyme: mixing of 6 mg/ml protein in 20 mM sodium acetate (pH 5.0), 50 mm NaCl with an equal volume of 4.0 M sodium formate, for mutant H25A: mixing of 0.0015 ml of protein in 25 mM sodium acetate pH 5.0, 60 mM NaCl and 1 mM tris-(2-carboxyethyl)phosphine with 0.0015 ml of 12% PEG 8000, 0.08 M (NH4)2SO4, 0.1 M sodium acetate and 1.5 mM phytate, 1 week, 22°C, X-ray diffraction structure determination and analysis at 1.7 A resolution, single-wavelength anomalous-diffraction phasing |
