title: Characterization and application of calcium-dependent β-propeller phytase from Bacillus amyloliquefaciens DS11.
abstract: The enzyme phytase has broad biotechnological applications, especially in the reduction of phytate, antinutritional factors that chelate essential minerals, in human and animal food. We investigated the enzymatic properties of β-propeller phytase (BPP) from Bacillus amyloliquefaciens DS11. Thermal refolding analysis demonstrated that BPP can remarkably restore its enzymatic activity in the presence of 5 mM Ca(2+) to 87% of its original activity after heating to 100 °C and subsequent cooling, indicating that the enzyme requires Ca(2+) for appropriate refolding. Furthermore, pH-dependent kinetic studies showed that BPP required excess Ca(2+) for its enzymatic activity as the pH decreased, suggesting that the optimal Ca(2+)-phytate ratio for enzymatic catalysis depends on the pH value of the environment. Finally, we verified the practical application of BPP at two different pH's using soybean meal as a natural source of phytate. As compared to a commercial phytase, BPP efficiently hydrolyzed food phytate over neutral pH ranges.
authors: Department of Food Science and Nutrition, Hallym University , Hallymdaehak-gil, Chuncheon, Gwangwon-do, 200-702, Korea.
authors: Jae-Hoon
authors: JH
authors: Shim
authors: Byung-Chul
authors: BC
authors: Oh
mesh_terms: D010832:6-Phytase / Q000737:chemistry*; D001407:Bacillus / Q000201:enzymology* / Q000302:isolation & purification; D002118:Calcium / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D002614:Chelating Agents; D006863:Hydrogen-Ion Concentration; D016297:Mutagenesis, Site-Directed; D010833:Phytic Acid / Q000737:chemistry; D013025:Glycine max / Q000737:chemistry; D014131:Trace Elements / Q000737:chemistry
chemical_list: D002614:Chelating Agents; D014131:Trace Elements; D010833:Phytic Acid; D010832:6-Phytase; D002118:Calcium