Abstract: The present invention provides a method for measuring glycated hemoglobin in a sample, which comprises directly oxidizing glycated hemoglobin in a sample, and then measuring a substance produced or consumed by the oxidation; and a method for measuring glycated hemoglobin in a sample, which comprises directly oxidizing glycated hemoglobin in a sample using an enzyme, and then measuring a substance produced or consumed by the oxidation. A method for measuring glycated hemoglobin of the present invention is useful for diagnosing lifestyle-related disease such as diabetes mellitus.

Abstract: The present invention provides a protein comprising an amino acid sequence in which arginine at position 61 of a protein comprising the amino acid sequence represented by SEQ ID NO: 1 is substituted to an amino acid selected from the group consisting of glycine, alanine, valine, leucine, serine, threonine, proline, cysteine, methionine, asparagine, glutamine, and aspartic acid; and a method for measuring a glycated hemoglobin in a sample, wherein the method comprises reacting a glycated hemoglobin in a sample with a protease to produce a glycated hexapeptide, then reacting the produced glycated hexapeptide with the aforementioned protein, and measuring a substance produced or consumed by the reaction.

Abstract: The present invention provides a protein comprising an amino acid sequence in which arginine at position 61 of a protein comprising the amino acid sequence represented by SEQ ID NO: 1 is substituted to an amino acid selected from the group consisting of glycine, alanine, valine, leucine, serine, threonine, proline, cysteine, methionine, asparagine, glutamine, and aspartic acid; and a method for measuring a glycated hemoglobin in a sample, wherein the method comprises reacting a glycated hemoglobin in a sample with a protease to produce a glycated hexapeptide, then reacting the produced glycated hexapeptide with the aforementioned protein, and measuring a substance produced or consumed by the reaction.

Abstract: The present invention provides a method for measuring glycated hemoglobin in a sample, which comprises directly oxidizing glycated hemoglobin in a sample, and then measuring a substance produced or consumed by the oxidation; and a method for measuring glycated hemoglobin in a sample, which comprises directly oxidizing glycated hemoglobin in a sample using an enzyme, and then measuring a substance produced or consumed by the oxidation. A method for measuring glycated hemoglobin of the present invention is useful for diagnosing lifestyle-related disease such as diabetes mellitus.

Abstract: Provided is a method for simply and accurately measuring sphingomyelin in a sample, and a kit therefore. The method is a method for measuring sphingomyelin in a sample, comprising reacting the sample with a phospholipase D which does not react with sphingomyelin and lysophosphatidylcholine but reacts with phosphatidylcholine, a lysophospholipase or a monoglyceride lipase, and a choline oxidase, eliminating the formed hydrogen peroxide, reacting the resultant with a phospholipase D which does not react with glycerol-3-phosphorylcholine and free fatty acid but reacts with sphingomyelin, and a choline oxidase, and measuring the formed hydrogen peroxide.

Abstract: Provided is a method for simply and accurately measuring sphingomyelin in a sample, and a kit therefor. The method is a method for measuring sphingomyelin in a sample, comprising reacting the sample with a phospholipase D which does not react with sphingomyelin and lysophosphatidylcholine but reacts with phosphatidylcholine, a lysophospholipase or a monoglyceride lipase, and a choline oxidase, eliminating the formed hydrogen peroxide, reacting the resultant with a phospholipase D which does not react with glycerol-3-phosphorylcholine and free fatty acid but reacts with sphingomyelin, and a choline oxidase, and measuring the formed hydrogen peroxide.