Provided are mutants PHY1, PHY4 and PHY5 of a wild-type phytase APPA. After being treated for 10 min at 80° C., the residual enzyme activities of the mutants PHY1, PHY4 and PHY5 are respectively higher by 33.85%, 53.11% and 75.86% compared with that of APPA-M; after being treated for 5 min at 85° C., the residual enzyme activities of the mutants PHY1, PHY4 and PHY5 are respectively higher by 14.89%, 28.45% and 44.94% compared with that of APPA-M, and the heat resistance of these mutants is significantly higher than that of APPA-M.

The subject invention provides microbe-based compositions comprising biologically pure yeasts, and/or one or more microbial growth by-products, such as enzymes. In certain embodiments, the enzymes are phytases. Methods of using these compositions to liberate phosphates from phytic acid-containing organic matter are also provided.

The invention relates to the use of at least one bacterial phytase in combination with one or more protease(s) in animal feed for improving weight gain and/or Feed Conversion Ratio (FCR), wherein the phytase is administered in one or more of the following amounts (dosage ranges): 1,000 FYT/kg feed, 2,000 FYT/kg feed 3,000 FYT/kg feed and wherein the protease is administered in one of the following amounts (dosage ranges): 10,000 units/kg feed, 11,000, 12,000, 13,000, 14,000, 15,000, 16,000, 17,000, 18,000, 19,000, 20,000 units/kg feed.

The present invention relates to variant phytase enzymes and their use thereof.

Provided is a method for safely and selectively producing a substrate culture product including a large amount of a desired degrading enzyme. A method for producing a substrate culture product used for feedstuff includes inoculating filamentous fungi bred so that a target degrading enzyme is produced by self-cloning in high productivity on a substrate, and producing the substrate culture product having functionality by ventilating the substrate to carry out solid culture.

The present invention relates to animal feed compositions comprising polypeptides having lysozyme activity and polypeptides having phytase activity and uses thereof.

Provided is a method for safely and selectively producing a substrate culture product including a large amount of a desired degrading enzyme. A method for producing a substrate culture product used for feedstuff includes inoculating filamentous fungi bred so that a target degrading enzyme is produced by self-cloning in high productivity on a substrate, and producing the substrate culture product having functionality by ventilating the substrate to carry out solid culture.

Disclosed herein is a method for expressing phytase in a filamentous fungus by using an optimized Escherichia coli phytase gene having a nucleotide sequence as shown in SEQ ID NO. 7 and a signal peptide having a nucleotide sequence as shown in SEQ ID NO. 12.

Disclosed is a thermostable phytase, in which at least one pair of introduced disulfide bonds is included in the amino acid sequence of wild-type Escherichia coli phytase or mutant Escherichia coli phytase, and after the introduction, the properties of the phytase can be improved, especially the heat stability, steam stability and granulation stability, which are superior to those of the existing wild-type or mutant phytase; compared to the engineered phytase in which disulfide bonds are introduced, the heat stability is also significantly improved.

Provided are mutants PHY1, PHY4 and PHY5 of a wild-type phytase APPA. After being treated for 10 min at 80 C., the residual enzyme activities of the mutants PHY1, PHY4 and PHY5 are respectively higher by 33.85%, 53.11% and 75.86% compared with that of APPA-M; after being treated for 5 min at 85 C., the residual enzyme activities of the mutants PHY1, PHY4 and PHY5 are respectively higher by 14.89%, 28.45% and 44.94% compared with that of APPA-M, and the heat resistance of these mutants is significantly higher than that of APPA-M.