Toyobo Co., Ltd.

Yosuke Sumida

Takahide Kishimoto

Hiroshi Aiba

Yuu Utashima

Shusaku Yanagidani

Rie Hirao

Hiroshi Kawaminami

Yasuhiro Yamazaki

Hiroaki Kitazawa

The invention provides streptolysin O containing a polypeptide comprising an amino acid sequence having deletion of a polypeptide extending from a lysine residue at position 2 of SEQ ID NO: 1 to any of an alanine residue at position 31, a glutamate residue at position 32, a serine residue at position 33, and an asparagine residue at position 34, and also having deletion of any of an isoleucine residue at position 465 to an alanine residue at position 472 of SEQ ID NO: 1 and all of the subsequent amino acid residues, as well as variants thereof and related DNA, vectors, transformants, and methods of use thereof.

Modified streptolysin O

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.

Growing community of inventors

Tsuruga, Japan

Yosuke Sumida