Provided are a transaminase mutant and use thereof. The transaminase mutant has an amino acid sequence obtained by mutation of an amino acid sequence shown in SEQ ID NO:1, the mutation at least includes one of the following mutation site combinations: T7C+S47C, Q78C+A330C, V137C+G313C, A217C+Y252C and L295C+C328C; or the transaminase mutant has an amino acid sequence which has the mutation sites in the mutated amino acid sequence and has 80% or more identity with the mutated amino acid sequence. The transaminase mutant realizes the change of protein structure and functions, reduces the enzyme amount, increases the enantiomeric excess (ee) value of a product, and reduces the difficulty of post-processing, so that the transaminase mutant may be suitable for industrial production.

The present disclosure provides engineered transaminase enzymes having improved properties as compared to a naturally occurring wild-type transaminase enzyme. Also provided are polynucleotides encoding the engineered transaminase enzymes, host cells capable of expressing the engineered transaminase enzymes, and methods of using the engineered transaminase enzymes to synthesize a variety of chiral compounds.

The present disclosure provides engineered transaminase enzymes having improved properties as compared to a naturally occurring wild-type transaminase enzyme. Also provided are polynucleotides encoding the engineered transaminase enzymes, host cells capable of expressing the engineered transaminase enzymes, and methods of using the engineered transaminase enzymes to synthesize a variety of chiral compounds.

The present invention refers to a modified D-amino acid oxidase (DAAO). In particular, the modified DAAO of the present invention has the activity of catalyzing the oxidation of D-glufosinate into PPO. Further, the modified DAAO of the present invention has increased activity of catalyzing the oxidation of D-glufosinate into PPO and/or increased stability as compared to SEQ ID NO: 4. The present invention also refers to the polynucleotide encoding the modified DAAO of the present invention, the vector and host cell expressing the modified DAAO of the present invention, and the method of producing L-glufosinate with the modified DAAO and host cell of the present invention.

The invention relates to nitrilases and to nucleic acids encoding the nitrilases. In addition methods of designing new nitrilases and method of use thereof are also provided. The nitrilases have increased activity and stability at increased pH and temperature.

The present invention has its object to provide a novel polypeptide having amidase activity to selectively hydrolyze S-enantiomer in racemic nipecotamide, a DNA encoding the polypeptide, a vector containing the DNA, a transformant transformed with the vector, and a method for producing an optically active carboxylic acid amide and an optically active carboxylic acid in which a racemic carboxylic acid amide is hydrolyzed with the polypeptide or the transformant.

The present invention refers to a modified D-amino acid oxidase (DAAO). In particular, the modified DAAO of the present invention has the activity of catalyzing the oxidation of D-glufosinate into PPO. Further, the modified DAAO of the present invention has increased activity of catalyzing the oxidation of D-glufosinate into PPO and/or increased stability as compared to SEQ ID NO: 4. The present invention also refers to the polynucleotide encoding the modified DAAO of the present invention, the vector and host cell expressing the modified DAAO of the present invention, and the method of producing L-glufosinate with the modified DAAO and host cell of the present invention.

Provided is a method for resolving an optical isomer from a racemate by using supercritical fluid extraction technology. The method is mainly applied to the separation of a product obtained after enzymatic resolution. Taking a preparation process of D-pantolactone as an example, the key point is to separate D-pantolactone and L-pantolactone from an enzymatic resolution liquid by means of supercritical fluid extraction.

This application relates to biological pharmacy and biochemical engineering, and more particularly to a method of preparing a (S)-1-benzyl-1,2,3,4,5,6,7,8-octahydroisoquinoline compound. This method includes: subjecting a 1-benzyl-1,2,3,4,5,6,7,8-octahydroisoquinoline raceme as a substrate to selective oxidation in the presence of a monoamine oxidase and the non-selective reduction to prepare the (S)-1-benzyl-1,2,3,4,5,6,7,8-octahydroisoquinoline compound, where the monoamine oxidase has an amino acid sequence as shown in SEQ ID NO: 1 or an amino acid sequence having an identity of more than 80% with SEQ ID NO: 1. The kinetic resolution is carried out in the presence of the monoamine oxidase as a catalyst and a reductant, and the resulting product has a high chiral purity.

Provided is a method for synthesizing a chiral diamine compound. The synthesizing method includes: converting a substrate represented by Formula I into a chiral diamine compound in Formula I by using a transaminase, herein n=1˜10, an R group represents an alkyl, a cycloalkyl, a heteroatom-containing alkyl, a heteroatom-containing cycloalkyl, a heteroatom-containing aryl, an amide compound residue, or an ether compound residue, and a hetero atom is at least one from among O, S and N; R1 and R2 are the same or not the same, the R1 and R2 are respectively and independently hydrogen, a C1-C3 alkyl, or an amino protecting group; and the transaminases are derived from a plurality of strains.