Kaneka Corporation

Kanegafuchi Kagaku Kogyo Kabushiki Kaisha

Kanegafuchi Chemical Industry Co., Ltd.

Hirokazu Nanba

Satomi Takahashi

Kazuyoshi Yajima

Yukio Yamada

Yasuhiro Ikenaka

Masayuki Takano

Makoto Ueda

Satohiro Yanagisawa

Sakayu Shimizu

Hideaki Yamada

Hiroyuki Kanamaru

Kenji Inoue

Takehisa Ohashi

Nobuo Nagashima

Tatsuya Honda

Masashi Izumida

Takahiro Ohishi

Masanobu Sugawara

Kohei Mori

Kazuhiko Yamada

Yoshiro Hiraishi

Kenichi Nishi

Ryuuji Miki

Kazuma Okubo

Yasuko Takaoka

Naoto Noro

The present invention has its object to provide a method for producing an L-amino acid comprising reacting a keto acid with an amino acid dehydrogenase and an enzyme having coenzyme regenerating ability to convert to a L-amino acid, wherein a coenzyme is added in two or more portions in the reaction. The method of the present invention enables efficient production of an L-amino acid useful as a synthetic intermediate such as a pharmaceutical intermediate with high optical purity by an enzymatic reductive amination independent of the purity of the keto acid used as a substrate.

Method for production of L-amino acid

The present invention provides a simple industrial process for producing an L- or D-optically active &#x3b1;-methylcysteine derivative or its salt, which is a useful pharmaceutical intermediate, from readily available, inexpensive raw materials. In a process for producing an L- or D-optically active &#x3b1;-methylcysteine derivative or its salt, a racemic N-carbamoyl-&#x3b1;-methylcysteine derivative or its salt is D-selectively cyclized with hydantoinase to produce a D-5-methyl-5-thiomethylhydantoin derivative or its salt and an N-carbamoyl-&#x3b1;-methyl-L-cysteine derivative or its salt, which are then subjected to deprotection of the amino group and the sulfur atom, and hydrolysis.

Process for producing optically active &#x3b1;-methylcysteine derivative

The present invention relates to novel D-amino acid oxidase isolated and purified from, a gene encoding the D-amino acid oxidase, a recombinant plasmid containing the gene, and a transformant into which the D-amino acid oxidase gene has been introduced, as well as a production method of D-amino acid oxidase including culturing the transformant. Moreover, the present invention relates to a production method of L-amino acids, 2-oxo acids or cyclic imines, which include reacting racemic amino acids with the D-amino acid oxidase, more preferably, a production method of L-amino acids, which includes reacting racemic amino acid with the D-amino acid oxidase, amino acid dehydrogenase and an enzyme having a coenzyme-regenerating activity. According to the present invention, L-amino acids, 2-oxo acids or cyclic imines can be produced with good efficiency in an industrial scale.

D-amino acid oxidase, and method for production of L-amino acid, 2-oxo acid, or cyclic imine

Disclosed are a novel hydantoin racemase and a process for producing an optically active N-carbamylamino acid or an optically active amino acid using the hydantoin racemase. A novel hydantoin racemase isolated and purified fromsp. Strain KNK519HR; a gene encoding the hydantoin racemase; a recombinant plasmid having the gene introduced therein; a transformant having the hydantoin racemase gene introduced therein; and a process for producing an optically active N-carbamylamino acid or an optically active amino acid characterized in that a 5-substituted hydantoin compound is treated in the presence of hydantoinase and N-carbamylamino acid amidohydrolase as well as the hydantoin racemase.

5-Substituted hydantoin racemase, DNA encoding the same, recombinant DNA, transformed cell, and process for production of optically active N-carbamylamino acid or optically active amino acid

It is an object of the present invention to provide a novel amidase that is useful for production of an optically active amino acid, and in particular, a D-amino acid, and a production method thereof. The present invention relates to a novel D-amidase isolated and purified from thesp. KNK1101J, a gene encoding the above amidase, a recombinant plasmid comprising the above gene, and a transformant into which the above amidase gene has been introduced. In addition, the present invention also relates to a method for producing the amidase, comprising culturing thesp. KNK1101J or the above transformant, and collecting the above amidase.

Polypeptide having amidase activity and gene thereof

The invention provides a formate dehydrogenase having high specific activity, small Km values for formate and NAD, broad temperature and pH ranges of stability, broad temperature and pH ranges for action, and capable of regenerating a coenzyme with good efficiency in case of being present in an enzymatic reduction reaction system without inactivated. The invention provides the enzyme mentioned above which has characteristics suited for industrial application by screening for soil formate dehydrogenase-producing microorganisms. The invention further provides a DNA containing the gene coding for the enzyme of the invention, a recombinant DNA constructed using a vector, and a transformant obtained by using this plasmid. The invention further provides a process for producing the formate dehydrogenase of the invention by using any microorganism of the genusor a transformant constructed by using a formate dehydrogenase gene derived from above strain of microorganism, and a process for regenerating a coenzyme by using said enzyme in an enzymatic reduction system.

Formate dehydrogenase tolerant to halogen compounds and process for producing the same

A DNA fragment coding for a decarbamylase protein improved in thermostability as the result of replacement of at least one base of a DNA fragment coding for a decarbamylase protein derived from a microorganism with another base and the resultant replacement of at least one of the corresponding amino acids, and its production process; a vector containing the DNA fragment; a transformant obtained by transformation with the vector; as well as a decarbamylase improved in thermostability and its production process. Also disclosed is a process for producing a D-.alpha.-amino acid, which comprises converting an N-carbamoyl-D-.alpha.-amino acid into the corresponding D-.alpha.-amino acid in an aqueous medium by the action of a decarbamylase having a thermostable temperature of 65.degree. C. or higher; and collecting the D-.alpha.-amino acid produced.

DNA coding for decarbamylase improved in thermostability and use thereof

Process for producing D-amino acids with composite immobilized enzyme

Process for the production of D-.alpha.-amino acids by hydrolysis of the

In a process for the production of a D-.alpha.-amino acid, in which an N-carbamyl-D-.alpha.-amino acid corresponding to the general formula: ##STR1## wherein R represents phenyl, hydroxy-substituted phenyl, substituted or unsubstituted alkyl, or thienyl, is converted by a microbial enzyme in an aqueous medium to a D-.alpha.-amino acid corresponding to the general formula: ##STR2## wherein R is the same as defined above, decarbamylase produced by a microorganism of the genus Comamonas, Blastobacter, Alcaligenes, Sporosarcina, Rhizobium, Bradyrhizobium or Arthrobacter is used as the enzyme converting the N-carbamyl-D-.alpha.-amino acid to the D-.alpha.-amino acid. The conversion of the N-carbamyl-D-.alpha.-amino acids to the D-.alpha.-amino acids is carried out in a neutral to alkaline pH range.

Decarbamylase isolated from comamonas or blastobacter

Decarbamylases are provided capable of producing D-.alpha.-amino acids by hydrolysis of N-carbamyl-D-.alpha.-amino acids. A source of the decarbamylases is recombinant microorganisms produced by gene manipulation methods. Decarbamylases having improved thermostability can be obtained in which amino acids at a thermostability-related site of a natural decarbamylase have been replaced with other amino acids by mutating a DNA fragment encoding the natural decarbamylase. Recombinant DNA is obtained from a vector DNA and a DNA fragment encoding a natural decarbamylase where the nucleic acid sequence encoding an amino acid at a thermostability-related site is replaced with a nucleic acid sequence encoding another amino acid. The recombinant DNA is used to produce transformants that produce thermostable decarbamylases. The decarbamylases may be immobilized in purified, partially-purified or crude form or in the form of decarbamylase-containing microbial cells on a support such as a polymer having ion exchange groups or covalent bonding groups. The presence of an antioxidant such as dithiothreitol results in an immobilized decarbamylase preparation that can be repeatedly used 30 times or more.

Recombinant decarbamylases for producing D-.alpha.-amino acids

The present invention is directed to a gene which is related to a D-N-carbamoyl-.alpha.-amino acid amidohydrolase which is an enzyme capable of converting D-N-carbamoyl-.alpha.-amino acids into D-.alpha.-amino acids; a recombinant plasmid in which a DNA fragment containing the gene is incorporated into a vector; a microorganism belonging to the genus Escherichia, Pseudomonas, Flavobacterium, Bacillus, Serratia, Corynebacterium, or Brevibacterium, which is transformed by incorporating the recombinant plasmid thereinto; a process for the production of D-N-carbamoyl-.alpha.-amino acid amidohydrolases, comprising the steps of cultivating the transformed microorganism and collecting the desired product therefrom; a D-N-carbamoyl-.alpha.-amino acid amidohydrolase obtained by the method; and a process for the production of D-.alpha.-amino acids with the aid of an action of the enzyme. The D-N-carbamoyl-.alpha.-amino acid amidohydrolase can be fixed on a support for immobilization and used as an immobilized enzyme.

Process for production of D-.alpha.-amino acids

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Takasago, Japan

Hirokazu Nanba