Noda Institute for Scientific Research

Kikkoman Corporation

Tatsuo Horiuchi

Toshiko Kurokawa

Tetsuya Oguma

Koichiro Tobe

Yasuji Koyama

Eiichi Nakano

Masaru Suzuki

Hiroki Tatsumi

Narimasa Saito

Naoki Eisaki

Hideko Otake

Minoru Hiruma

Toshiyuki Suzuki

Ayumu Nagahara

Tsuyoshi Ohno

Disclosed are a pyruvate orthophosphate dikinase gene coding for a polypeptide containing the amino acid sequence of SEQ ID NO:1 or an amino acid sequence where in said amino acid sequence one or more amino acids are added, deleted or substituted and bringing about the activity of pyruvate orthophosphate dikinase; recombinant DNA having the pyruvate orthophosphate dikinase gene integrated in vector DNA; and a process for producing pyruvate orthophosphate dikinase, which comprises culturing a microorganism belonging to the genus Escherichia carrying the above recombinant DNA in a medium, and recovering pyruvate orthophosphate dikinase from the resulting culture. The pyruvate orthophosphate dikinase gene and a process for producing pyruvate orthophosphate dikinase are provided.

Pyruvate orthophosphate dikinase gene, recombinant DNA, and process for

N-acetylmannosamine dehydrogenase gene derived from a microorganism belonging to the genus Flavobacterium, e.g., Flavobacterium sp. No. 141-8 strain and defined by a specific restriction enzyme map which encodes 271 amino acid sequence. Using the recombinant DNA, N-acetylmannosamine dehydrogenase can be produced in a simpler manner in an industrial scale. The enzyme is useful for quantitative determination of sialic acid.

N-acetylmannosamine dehydrogenase gene and novel recombinant DNA as well

The present invention relates to a novel cycloisomaltooligosaccharide selected from the group consisting of novel cycloisomaltoheptaose having a cyclic structure composed of 7 glucose residues in .alpha.-1,6 linkage, novel cycloisomaltooctaose having a cyclic structure composed of 8 glucose residues in .alpha.-1,6 linkage and novel cycloisomaltononaose having a cyclic structure composed of 9 glucose residues in .alpha.-1,6 linkage, novel cycloisomaltooligosaccharide synthase forming said oligosaccharides from dextran, and a process for producing said oligosaccharides by use of said enzyme or a microorganism capable of producing said enzyme.

Enzyme for producing novel cyclooisomaltooligosaccharides

Cycloisomaltooligosaccharides

L-Fucose dehydrogenase having the following Physicochemical properties (1) and (2):

L-fucose dehydrogenase, a process for production thereof, quantitative

The present invention relates to a novel NADH kinase which has high stability and is specific for NADH, and a process for producing the NADH kinase by culturing a yeast belonging to the genus Pichia in a culture medium, and this enzyme permits highly sensitive determination of NADH alone and hence is useful in the field of clinical medicine.

NADH kinase and a process for producing the same

N-Acetylhexosamine-dehydrogenase which takes off hydrogen from N-acetylglucosamine or N-acetylgalactosamine to convert them to N-acetylglucosaminolactone or N-acetylgalactosaminolactone, respectively, and, at the same time, reduces co-enzymes NAD.sup.+ to NADH is provided herein. The enzyme of this invention can be obtained by culturing, in a medium, a strain belonging to Genus Pseudomonas and having an ability to produce N-acetylhexosamine-dehydrogenase, followed by collecting the enzyme from the cultured product. Herein is also provided a method for quantitatively analyzing N-acetylglucosamine or N-acetylgalactosamine which comprises reacting N-acetylglucosamine-dehydrogenase upon a sample containing N-acetylglucosamine or N-acetylgalactosamine and measuring the quantity of the resulting NADH.

N-acetylhexosamine-dehydrogenase, process for producing same, method for

N-Acetylmannosamine dehydrogenase which takes off hydrogen from N-acetylmannosamine to convert it into N-acetylmannosaminolactone and, at the same time, reduces coenzyme NAD into NADH. This enzyme can be obtained by culturing, in a medium, a strain belonging to Genus Flavobacterium and having an ability to produce N-acetylmannosamine dehydrogenase producing activity, and then collecting it. This enzyme is usable in the quantitative analysis of N-acetylmannosamine or sialic acid.

N-acetylmannosamine dehydrogenase, process for its production, method

A method for quantitative determination of N-acetylhexosamine which comprises (a) allowing an N-acetylhexosamine oxidase to act upon an N-acetylhexosamine-containing liquid in the presence of oxygen and then (b) determining the amount of oxygen consumed in the oxidation reaction or the amount of hydrogen peroxide or N-acetylhexaminic acid formed in the oxidation reaction. Further, a reagent for quantitative determination of N-acetylhexosamine, characterized by containing an N-acetylhexosamine oxidase.

Method and reagent for quantitative determination of N-acetylhexosamine

An N-acetylhexosamine oxidase having the following physiochemical properties. (1) Action and specificity for substrate Oxidizes N-acetylhexosamine in the presence of oxygen to form N-acetylhexosaminic acid and hydrogen peroxide. Hardly acts or does not act at all on hexose and hexosamine. (2) Optimum pH and stable pH range When a potassium phosphate buffer solution contining 0.1M glycine is used, an optimum pH is 7.5 to 8.5 and a stable pH range is 3 to 9. (3) Molecular weight Has a molecular weight of about 140,000 to 150,000 when measured according to a gel filtration method using Sephadex G-200 by the use of 0.05M potassium phosphate buffer solution.

N-acetylhexosamine oxidase and process for producing the same

A method for the assay of .alpha.-amylase activity, which comprises adding an .alpha.-amylase-containing sample to maltohexaitol or maltohexaonic acid used as substrate, reacting, at the same time or subsequent to the addition, .alpha.-glucosidase with the resulting mixture, and determining the reaction product to assay the .alpha.-amylase activity.

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Noda, Japan

Tatsuo Horiuchi