Kabushiki Kaisha Hayashibara Seibutsu Kagaku Kenkyujo

Kabushiki Kaisha Hayashibara Seibutsu

Tetsuya Nakada

Michio Kubota

Hiroto Chaen

Toshio Miyake

Toshiyuki Sugimoto

Tomoyuki Nishimoto

Kazuhiko Maruta

Hajime Aga

Kozo Yamamoto

Tetsuya Ohashi

Shuzo Sakai

An object of the present invention is to provide a novel ketose 3-epimerase, a process for producing the same, a DNA encoding the enzyme, a recombinant DNA and transformant comprising the DNA, and a process for producing a ketose by using the enzyme. The present invention solves the above objects by providing a ketose 3-epimerase which is obtainable from a microorganism of the genus, a process for producing the same, a DNA encoding the enzyme, a recombinant DNA and transformant comprising the DNA, and a process for converting D- or L-ketohexose into corresponding D- or L-ketohexose by epimerizing the hydroxyl group at the C-3 position of the D- or L-ketohexose; and D- or L-ketopentose into corresponding D- or L-ketopentose by epimerizing the hydroxyl group at the C-3 position of the D- or L-ketopentose; by using the enzyme.

Ketose 3-epimerase, its preparation and uses

An object of the present invention is to provide a crystalline saccharide having novel physical properties, a preparation and uses thereof. The present invention solves the above objects by providing a porous crystalline saccharide having a number of pores, a process for producing the same, comprising the step of keeping hydrous crystalline saccharide at an ambient temperature or higher in an organic solvent for the dehydration, and the use thereof.

Porous crystalline saccharide, its preparation and uses

Objects of the present invention are to provide a novel anhydrous crystalline &#x3b2;-maltose, its preparation and uses. The present invention attains the above objects by providing an anhydrous crystalline &#x3b2;-maltose with a melting point of 154 to 159&#xb0; C.; a process for producing the same, comprising a step of keeping hydrous crystalline &#x3b2;-maltose in an organic solvent at an ambient temperature or higher for the dehydration; and uses of the same.

Anhydrous crystalline &#x3b2;-maltose, its preparation and uses

A thermostable trehalose phosphorylase which is obtainable from microorganisms of the genus Thermoanaerobium and which hydrolyzes trehalose in the presence of an inorganic phosphoric acid to form D-glucose and .beta.-D-glucose-1-phosphoric acid. The trehalose phosphorylase can be also prepared by recombinant DNA technology. When the enzyme is allowed to contact with .beta.-D-glucose-1-phosphoric acid as a saccharide donor in the presence of other saccharides, glucosyl-transferred saccharides including glucosyl-D-galactoside, which are conventionally known but scarcely obtainable, can be produced on an industrial-scale and in a relatively-low cost.

Trehalose phosphorylase, its preparation and use

A polypeptide possessing maltotetraose-forming amylase activity with a revealed amino acid sequence. The polypeptide has features that it acts on starch to mainly produce maltotetraose, and that it has a molecular weight of 50,000.+-.10,000 when electrophoresed on SDS-polyacrylamide gel. The polypeptide can be advantageously used in industrial process.

DNA encoding a polypeptide possessing maltotetraose-forming amylase

A .beta.-fructofuranosidase with a molecular weight of 49,000.+-.5,000 daltons on SDS-PAGE, an isoelectric point of 4.6.+-.0.5, an optimum pH of about 5.5-6.0, and an optimum temperature of about 50.degree. C. in the presence of calcium ion. The enzyme acts on saccharides with a .beta.-fructofuranosidic linkage and other substances including other saccharides, sugar alcohols, and alcohols to produce fructosyl-transferred saccharides in a relatively high yield.

.beta.-fructofuranosidase, its preparation and uses

Trehalose phosphorylase, its preparation and uses

Trehalose phosphorylase its preparation and uses

.beta.-fructofuranosidase its preparation and uses

Disclosed are novel thermostable non-reducing saccharides-forming enzyme, its preparation and uses. The enzyme is obtainable from the culture of microorganisms such as Sulfolobus acidocaldarius (ATCC 33909 and ATCC 49426) and Sulfolobus solfataricus (ATCC 35091 and ATCC 35092), and capable of forming non-reducing saccharides having a trehalose structure as an end unit when allowed to act on reducing partial starch hydrolysates at a temperature of over 55.degree. C. Glucoamylase and .alpha.-glucosidase readily yield trehalose when allowed to act on the non-reducing saccharides. These non-reducing saccharides and trehalose are extensively useful in food products, cosmetics and pharmaceuticals.

Thermostable non-reducing saccharide-forming enzyme its production and

Disclosed is a novel .alpha.-glycosyl derivative of a catecholamine or its salt, said .alpha.-glycosyl derivative being prepared by allowing a saccharide-transferring enzyme together with or without glucoamylase to act on a solution containing an .alpha.-glucosyl saccharide and one of catecholamines in order to form an .alpha.-glycosyl derivative of said catecholamines, and recovering the resultant .alpha.-glycosyl derivative. The .alpha.-glycosyl derivative overcomes conventional drawbacks of catecholamines, and does not substantially exhibit or have a reducing activity and undesirable toxicity, but has a relatively-high stability and exerts the inherent physiological activities of catecholamines in vivo. Thus, the .alpha.-glycosyl derivative is advantageously used as a variety of pharmaceuticals in the form of an injection, tablet, etc.

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Okayama, Japan

Tetsuya Nakada