Abstract: As a method for producing a 3-hydroxyisobutyric acid ester using a biocatalyst, a method for producing a 3-hydroxyisobutyric acid ester, including a step of allowing an alcohol or phenol to act on 3-hydroxyisobutyryl-CoA in the presence of alcohol acyltransferase to produce a 3-hydroxyisobutyric acid ester is provided.

Abstract: A method for producing an active-form mutant enzyme, by specifying a protein of which a native form exhibits an enzyme activity but which has 10% or less enzyme activity of the native form when a gene of the protein is expressed to provide an inactive-form enzyme; determining a sequence conservation of amino acid residues in an amino acid sequence of the inactive-form enzyme and specifying amino acid residue(s) for which sequence conservation in the inactive-form enzyme is lower than sequence conservation of other amino acid(s) of the same residue; preparing a gene having a base sequence that codes for the amino acid sequence of the inactive-form enzyme in which at least one said specified amino acid residue is substituted by another amino acid with a higher sequence conservation; and expressing the gene to obtain an enzyme that exhibits an enzyme activity of the native form protein.

Abstract: Provided are a method for obtaining an HNL gene and HNL derived from a millipede other than Chamberlinius hualienensis, and preparing a practically useable amount of HNL; and a method for producing optically active cyanohydrin using this HNL. A method for producing a millipede-derived HNL gene. A method that includes the selection of a gene having a base sequence that encodes a conserved amino acid sequence TAX1DIX2G (SEQ ID NO: 15) or VPNGDKIH (SEQ ID NO: 16) of millipede-derived HNL from genes present in an organism belonging to the Diplopoda. A protein having an amino acid sequence of any of (1)-(3) and having HNL activity. (1) An amino acid sequence listed in any of SEQ ID NOS: 1, 3, 5, 7, 9, 11, 13, 83, 85, 87, or 89; (2) an amino acid sequence having amino acids deleted, substituted, and/or added in an amino acid sequence of (1); or (3) an amino acid sequence having 90% or greater identity to an amino acid sequence of (1).

Abstract: A method for expressing, as a soluble protein or an active-form mutant enzyme, an enzyme that cannot be expressed as a soluble protein or an active-form enzyme in a heterologous expression system or that is obtained in a minute amount even when an active-form enzyme is expressed, the method including a technique for selecting an effective mutation site and a mutated amino acid. A new active-form mutant enzyme is also disclosed. The method involves: specifying an insoluble protein or an inactive-form enzyme; specifying a hydrophilic amino acid in a hydrophobic domain and/or a hydrophobic amino acid in a hydrophilic domain of an ?-helix structure portion of the insoluble protein or the inactive-form enzyme and preparing a gene that codes for an amino acid sequence in which a substitution is made to the hydrophilic amino acid in the hydrophobic domain and/or the hydrophobic amino acid in the hydrophilic domain.

Abstract: The present invention provides a process for industrial production of chiral-1,1-difluoro-2-propanol. More specifically, a microorganism having the activity to cause asymmetric reduction of 1,1-difluoroacetone or an enzyme having the same activity is allowed to act on 1,1-difluoroacetone, whereby chiral-1,1-difluoro-2-propanol can be produced with high optical purity and in good yield. The process for production of the present invention is easy for industrial implementation.

Abstract: Disclosed is a method for quantifying L-tryptophan involving a step for mixing a specimen, L-tryptophan oxidase, and water, a step for allowing the obtained reaction solution to stand a predetermined period of time in the presence of oxygen, and a step for measuring the reaction product resulting from action of enzymes present in the reaction solution after allowing to stand. Also disclosed are a kit used to quantify the L-tryptophan containing L-tryptophan oxidase, and an enzyme sensor using the L-tryptophan oxidase. This method, kit and enzyme sensor use an L-tryptophan-specific enzyme, so are capable of quantifying L-tryptophan even in the presence of other amino acids.

Abstract: The objective of the present invention is to provide a (R)-hydroxynitrile lyase which is more stable than a hydroxynitrile lyase derived from a plant, a gene which encodes the hydroxynitrile lyase and by which heterologous expression is possible, and a method for producing the hydroxynitrile lyase. The (R)-hydroxynitrile lyase according to the present invention is characterized in having the specific amino acid sequence such as the amino acid sequence of SEQ ID NO: 3.