Toyobo Co., Ltd.

Toyo Boseki Kabushiki Kaisha

Kyoto University

Hiroshi Aiba

Takahide Kishimoto

Yuu Utashima

Yosuke Sumida

Hiroshi Kawaminami

Shusaku Yanagidani

Rie Hirao

Yoshiaki Nishiya

Yasuhiro Yamazaki

Masao Kitabayashi

Tadayuki Imanaka

Yuji Tsuji

Hiroaki Kitazawa

Haruyuki Atomi

The present invention provides a novel glucose dehydrogenase that has excellent substrate specificity and that is suitable for use in SMBG. The present invention provides a flavin-bound glucose dehydrogenase having the following characteristics (1) to (5): (1) Temperature stability: stable at a temperature of 45&#xb0; C. or lower; (2) stable at a pH range of 4.5 to 7.5; (3) substrate specificity: the reactivity to D-xylose, maltose, or D-galactose is 2% or less, based on the reactivity to D-glucose taken as 100%; (4) optimal activity temperature: 34 to 47&#xb0; C.; and (5) optimal activity pH: 6.3 to 6.7.

Glucose dehydrogenase

Provided is a flavin adenine dinucleotide-dependent glucose dehydrogenase comprising a polypeptide having an amino acid sequence with 78% or more identity to the amino acid sequence of SEQ ID NO: 3, and having glucose dehydrogenase activity.

The present invention provides a novel glucose dehydrogenase that has excellent substrate specificity, specific activity, thermal stability, and the like, and that is suitable for use in SMBG sensors. The present invention provides a purified polypeptide comprising an amino acid sequence having at least 80% identity to the sequence of SEQ ID NO: 1 and having glucose dehydrogenase activity.

An object of the present invention is to provide a novel glucose dehydrogenase, a method for producing the glucose dehydrogenase, and applications of the glucose dehydrogenase. An isolated flavin-binding glucose dehydrogenase comprising a polypeptide having an amino acid sequence with 80% or more identity to the amino acid sequence of SEQ ID NO: 1, and having glucose dehydrogenase activity is provided.

An object of the present invention is to provide a novel glucose dehydrogenase, a method for producing the glucose dehydrogenase, and applications of the glucose dehydrogenase. The flavin-binding glucose dehydrogenase of the invention has the following characteristics (1) and (4): (1) Molecular weight: the molecular weight of a polypeptide moiety in the enzyme is about 68 kDa as measured by SDS-polyacrylamide electrophoresis; (2) Km value: the Km value for D-glucose is about 15 mM or less; (3) Temperature stability: stable at a temperature of 55&#xb0; C. or less; and (4) pH stability: stable at a pH range of 3.0 to 8.5.

The present invention provides AP that has a high specific activity and preferably has superior reactivity with respect to various luminescent substrates generally used for high-sensitivity immunoassay analysis. Further preferably, the present invention provides AP having a thermal stability higher than that of CIAP. The alkaline phosphatase of the present invention is derived from the genusand has the following characteristics: (A) molecular weight: about 104,000; (B) optimum reaction pH: about 9.5; (C) stable pH range: 5.5 to 10.4; (D) thermal stability: 65&#xb0; C., and (E) specific activity: 5,000 U/mg or more.

Alkaline phosphatase

The invention provides a glucose dehydrogenase that is an extremely stable enzyme having a thermostability of 80&#xb0; C. or more, and that does not substantially act upon saccharides other than glucose (e.g., having a reactivity of less than 3% with respect to maltose, galactose, and xylose). The invention also provides a method for producing such an enzyme, and a composition for quantifying glucose using such an enzyme.

The present invention provides glucose dehydrogenase which is excellent in heat resistance and substrate specificity and is not affected by dissolved oxygen. Specifically, the present invention relates to glucose dehydrogenase characterized by being derived from an eukaryotic organism and keeping 90% or more activity after being treated with heat at 55&#xb0; C. for 15 minutes in a liquid form compared with the activity before being treated.

The present invention relates to a method for lowering activity with respect to maltose in glucose measurement comprising a step of reacting modified pyrroloquinoline quinone dependent glucose dehydrogenase subjected to amino acid sequence modification, wherein pyrroloquinoline quinone dependent glucose dehydrogenase is reacted in the presence of at least one type of substance selected from the group comprising succinic acid, malonic acid, glutaric acid, malic acid, phthalic acid, 2-ketoglutaric acid, 3,3-dimethylglutaric acid, pimeric acid, suberic acid, adipic acid, maleic acid, potassium chloride, ammonium chloride, diammonium hydrogen citrate, L-lysine, taurine, calcium glycerate, amino-n-butyric acid, sodium glycolate, sodium &#x3b1;-ketoglutarate, fumaric acid, glycine, glutamic acid, serine and citric acid.

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Tsuruga, Japan

Hiroshi Aiba