Abstract: The present invention relates to a protein-immobilized membrane (14) including a cell membrane homologous layer (14A) and a protein (14B) immobilized to the cell membrane homologous layer (14A), where the protein contains cytochrome or a cytochrome complex. The present invention also relates to a method for forming a protein-immobilized membrane (14), and an enzyme-immobilized electrode and a biosensor (X1) provided with a protein-immobilized membrane (14). Preferably, the cell membrane homologous layer (14A) may contain a phospholipid polymer, and the protein (14B) may be CyGDH including an ? subunit having a glucose dehydrogenase activity and cytochrome C having a function of electron transfer.

Abstract: The present invention relates to a protein-immobilized membrane (14) including a cell membrane homologous layer (14A) and a protein (14B) immobilized to the cell membrane homologous layer (14A), where the protein contains cytochrome or a cytochrome complex. The present invention also relates to a method for forming a protein-immobilized membrane (14), and an enzyme-immobilized electrode and a biosensor (X1) provided with a protein-immobilized membrane (14). Preferably, the cell membrane homologous layer (14A) may contain a phospholipid polymer, and the protein (14B) may be CyGDH including an ? subunit having a glucose dehydrogenase activity and cytochrome C having a function of electron transfer.

Abstract: The present invention relates to a method for purifying target protein which contains electron transfer protein, from a protein solution containing the target protein, by means of liquid chromatography. The liquid chromatography is performed as follows: First, the protein solution is introduced into a column which is filled with a packing agent, thereby causing the packing agent to bond to the target protein. Then, impurities are removed, and then the target protein is eluted from the packing agent in an eluent which contains a hydroxy-cholate. An example of the target protein is glucose dehydrogenase which contains a protein having glucose dehydrogenation activity. The liquid chromatography is performed as a combination of hydrophobic chromatography and anion exchange chromatography.

Abstract: The present invention relates to a method for purifying target protein which contains electron transfer protein, from a protein solution containing the target protein, by means of liquid chromatography. The liquid chromatography is performed as follows: First, the protein solution is introduced into a column which is filled with a packing agent, thereby causing the packing agent to bond to the target protein. Then, impurities are removed, and then the target protein is eluted from the packing agent in an eluent which contains a hydroxy-cholate. An example of the target protein is glucose dehydrogenase which contains a protein having glucose dehydrogenation activity. The liquid chromatography is performed as a combination of hydrophobic chromatography and anion exchange chromatography.

Abstract: A sensor storage container is provided that allows sensors to be checked visually from the outside. A container is used for storing sensors including an oxidation-reduction enzyme that oxidizes or reduces an object to be analyzed, a mediator that mediates the transfer of electrons caused by oxidation or reduction, and a detection means that detects the oxidation or reduction reaction. The container is transparent or semi-transparent in whole or in part and thereby the sensors can be checked visually from the outside of the container. This container may be composed of a container body and a lid. The container body may be provided with a scale. Preferably, the sensors are those produced using a ruthenium metal complex as the mediator.

Abstract: Substrate specificity for glucose of a glucose dehydrogenase having the amino acid sequence of SEQ ID NO: 13 is improved by substituting another amino acid residue for the amino acid residue at position 472 and/or 475.

Abstract: Substrate specificity for glucose of a glucose dehydrogenase having the amino acid sequence of SEQ ID NO: 13 is improved by substituting another amino acid residue for the amino acid residue at position 472 and/or 475.

Abstract: The present invention relates to a technique for measuring a glucose level by utilizing a reaction system containing an enzyme and an electron carrier. In accordance with the glucose level measuring method of the present invention, glucose dehydrogenase with cytochrome C attached thereto or glucose dehydrogenase derived from a microorganism belonging to a burkholderia genus is used as the enzyme, and a Ru compound is used as the electron carrier. The present invention further provides a glucose sensor in which glucose dehydrogenase with cytochrome C attached thereto or glucose dehydrogenase derived from derived from a microorganism belonging to a burkholderia genus is used as the enzyme, and a Ru compound is used as the electron carrier.

Abstract: Substrate specificity for glucose of a glucose dehydrogenase having the amino acid sequence of SEQ ID NO: 13 is improved by substituting another amino acid residue for the amino acid residue at position 472 and/or 475.

Abstract: The present invention relates to an analytical instrument (1) which includes a flow path (5) for moving a sample containing blood cells, an introduction port (50) for introducing the sample into the flow path (5), a reagent portion (51) arranged in the flow path (5), and an electron detection medium (52) for obtaining information necessary for analyzing an analysis target component contained in the sample in relation with an amount of electrons transferred. The reagent portion (51) contains an electron mediator for supplying an electron taken from the analysis target component in the sample to the electron detection medium (52), and at least part of the reagent portion is positioned adjacent to the introduction port (50).

Abstract: A process for producing glucose dehydrogenases. This process comprises transferring a DNA containing a sequence represented by SEQ ID NO:1 which encodes an ? subunit having a glucose dehydrogenase activity and a ? subunit being an electron transfer protein into a microorganism belonging to the genus Pseudomonas to thereby construct a transformant, and culturing this transformant so as to allow the production of a first glucose dehydrogenase containing the above-described ? subunit and a second glucose dehydrogenase free from the ? subunit. The ? subunit as described above has a molecular weight of about 60 kDa measured by, for example, SDS-polyacrylamide gel electrophoresis under reducing conditions, while the ? subunit as described above has a molecular weight of about 43 kDa measured by, for example, SDS-polyacrylamide gel electrophoresis under reducing conditions.

Abstract: A mutant glucose dehydrogenase having the amino acid sequence of SEQ ID NO: 3 or an amino acid sequence of SEQ ID NO: 3 including substitution, deletion, insertion or addition of one or more amino acid residues other than the amino acid residue at the 365th position and having glucose dehydrogenase activity, wherein an amino acid residue at a position corresponding to the 365th position of, the amino acid sequence is replaced with another amino acid residue, and the mutant glucose dehydrogenase shows an improved substrate specificity to glucose.

Abstract: A mutant glucose dehydrogenase having an improved substrate specificity to glucose, which is a protein comprising the amino acid sequence depicted in SEQ ID NO:3 or an amino acid sequence having the substitution, deletion, insertion or addition of one or more amino acid residues excluding amino acid 365 in the amino acid sequence depicted in SEQ ID NO:3 and having a glucose dehydrogenase activity, the amino acid residue corresponding to amino acid 365 being substituted by other amino acid residue.

Abstract: The present invention relates to a protein-immobilized membrane (14) including a cell membrane homologous layer (14A) and a protein (14B) immobilized to the cell membrane homologous layer (14A), where the protein contains cytochrome or a cytochrome complex. The present invention also relates to a method for forming a protein-immobilized membrane (14), and an enzyme-immobilized electrode and a biosensor (X1) provided with a protein-immobilized membrane (14). Preferably, the cell membrane homologous layer (14A) may contain a phospholipid polymer, and the protein (14B) may be CyGDH including an ? subunit having a glucose dehydrogenase activity and cytochrome C having a function of electron transfer.

Abstract: The present invention relates to an analytical instrument (1) which includes a flow path (5) for moving a sample containing blood cells, an introduction port (50) for introducing the sample into the flow path (5), a reagent portion (51) arranged in the flow path (5), and an electron detection medium (52) for obtaining information necessary for analyzing an analysis target component contained in the sample in relation with an amount of electrons transferred. The reagent portion (51) contains an electron mediator for supplying an electron taken from the analysis target component in the sample to the electron detection medium (52), and at least part of the reagent portion is positioned adjacent to the introduction port (50).

Abstract: Substrate specificity for glucose of a glucose dehydrogenase having the amino acid sequence of SEQ ID NO: 13 is improved by substituting another amino acid residue for the amino acid residue at position 472 and/or 475.

Abstract: A mutant glucose dehydrogenase having an improved substrate specificity to glucose, which is a protein comprising the amino acid sequence depicted in SEQ ID NO:3 or an amino acid sequence having the substitution, deletion, insertion or addition of one or more amino acid residues excluding amino acid 365 in the amino acid sequence depicted in SEQ ID NO:3 and having a glucose dehydrogenase activity, the amino acid residue corresponding to amino acid 365 being substituted by other amino acid residue.

Abstract: The present invention relates to technology for constructing a reaction system including a test target, an oxidation-reduction enzyme, and an electron mediator, and measuring the concentration of the test target by an electrochemical process. A Ru compound is used as the electron mediator. The present invention provides a concentration test instrument including a substrate, first and second electrodes formed on the substrate, and a reagent layer formed as a solid. The reagent layer contains an oxidation-reduction enzyme and a Ru compound, and is constituted so as to dissolve and construct a liquid phase reaction system when a sample liquid is supplied.

Abstract: The present invention relates to technology for constructing a reaction system including a test target, an oxidation-reduction enzyme, and an electron mediator, and measuring the concentration of the test target by an electrochemical process. A Ru compound is used as the electron mediator. The present invention provides a concentration test instrument including a substrate, first and second electrodes formed on the substrate, and a reagent layer formed as a solid. The reagent layer contains an oxidation-reduction enzyme and a Ru compound, and is constituted so as to dissolve and construct a liquid phase reaction system when a sample liquid is supplied.

Abstract: The present invention relates to technology for constructing a reaction system including a test target, an oxidation-reduction enzyme, and an electron mediator, and measuring the concentration of the test target by an electrochemical process. A Ru compound is used as the electron mediator. The present invention provides a concentration test instrument including a substrate, first and second electrodes formed on the substrate, and a reagent layer formed as a solid. The reagent layer contains an oxidation-reduction enzyme and a Ru compound, and is constituted so as to dissolve and construct a liquid phase reaction system when a sample liquid is supplied.