Abstract: Provided is an application of trehalase in fermentative production. The trehalase has amino acid sequences shown in SEQ ID NO.6, SEQ ID NO.7, and SEQ ID NO.8. Provided are methods for producing and applying trehalase, particularly being applied in the production and fermentation of alcohol and an amino acid.

Abstract: 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.

Abstract: Provided is an application of trehalase in fermentative production. The trehalase has amino acid sequences shown in SEQ ID NO.6, SEQ ID NO.7, and SEQ ID NO.8. Provided are methods for producing and applying trehalase, particularly being applied in the production and fermentation of alcohol and an amino acid.

Abstract: Provided is an ? amylase variant obtained by the mutation or deletion of at least one amino acid residue in the amino acid sequence of a parent ? amylase, and at the same time, same is an ? amylase maintaining the capability of the parent to hydrolyse ?-1,4 glycosidic bond, wherein the amino acid sequence homology of the two reaches 95% or more. A series of ? amylase variants provided therein have a relatively high catalytic activity under acidic conditions of pH 5.0 and high temperatures of at least 100° C.

Abstract: The present invention discloses an L-type amylase variant and use thereof. The ?-amylase variant is obtained by deleting the first N-terminal amino acid residue V from the ?-amylase of B. licheniformis and replacing it with three other amino acid residues DGL. The ?-amylase variant provided by the present invention has high catalytic activity under the acidic conditions of pH 5.0-5.8 and a high temperature of 100° C. or above. The acid resistance and thermal stability of these ?-amylase variants are suitable for starch liquefaction.

Abstract: Truncated pullulanases having an N-terminal deletion in a parental pullulanase are provided. These truncated pullulanases have altered properties as compared to the parental pullulanase, including an increased saccharification rate and higher catalytic activity at acidic pH values below 4.5 and higher temperatures of up to 64° C. These truncated pullulanase also have improved thermal stability as compared to the parental enzyme. Also provided are compositions containing the truncated pullulanases and a glucoamylase, and processes for applying the truncated pullulanases and compositions in the starch industry. Polynucleotides that encode the truncated pullulanases, and recombinant host cells for producing the truncated pullulanases are also described.

Abstract: Provided is an ? amylase variant obtained by the mutation or deletion of at least one amino acid residue in the amino acid sequence of a parent ? amylase, and at the same time, same is an ? amylase maintaining the capability of the parent to hydrolyse ?-1,4 glycosidic bond, wherein the amino acid sequence homology of the two reaches 95% or more. A series of ? amylase variants provided therein have a relatively high catalytic activity under acidic conditions of pH 5.0 and high temperatures of at least 100° C.

Abstract: The present invention discloses an L-type amylase variant and use thereof. The ?-amylase variant is obtained by deleting the first N-terminal amino acid residue V from the ?-amylase of B. licheniformis and replacing it with three other amino acid residues DGL. The ?-amylase variant provided by the present invention has high catalytic activity under the acidic conditions of pH 5.0-5.8 and a high temperature of 100° C. or above. The acid resistance and thermal stability of these ?-amylase variants are suitable for starch liquefaction.