Abstract: A method of quantifying glucose in a solution characterized in that electric potential measurement is conducted by potentiometry using a glucose dehydrogenase that requires a flavin compound as a coenzyme. It is preferable to carry out the quantification using a glucose dehydrogenase derived from a filamentous fungus, in particular derived from Aspergillus oryzae or Aspergillus terreus.

Abstract: Object: An object of the present invention is to provide a more practically advantageous enzyme usable as a reagent for measuring blood glucose than the known enzymes used as blood glucose sensors. Method for Achieving the Object: A modified flavin adenine dinucleotide dependent glucose dehydrogenase (FADGDH) with more improved heat stability than FADGDH derived from wild-type FADGDH, the modified FADGDH being derived from preferably a eukaryote, more preferably a filamentous fungus, and furthermore preferably an Aspergillus fungus, and, for example, those having a primary structure with at least one amino acid substituted, deleted, inserted or added to FADGDH having an amino acid sequence represented by SEQ ID Nos. 2 or 46 in the sequence table.

Abstract: The present invention relates to a method for enhancing stability of a composition comprising soluble glucose dehydrogenase (GDH). Soluble GDH is preferably FAD-dependent GDH derived from filamentous fungus, and the best effect is observed in FAD-GDH derived from A. oryzae or FAD-GDH derived from A. terreus. According to the invention, in a composition comprising soluble glucose dehydrogenase (GDH), stability of GDH can be enhanced by coexisting the enzyme with one or more compounds selected from amino acids and sugars which are not substrate of the enzyme, thus expected to enhancing a measurement accuracy of glucose.

Abstract: An X-ray analysis apparatus has information about a relationship between selection of a measurement type and a replacement work of optical parts and shows, on a screen of a display, graphical information about optical parts which should be changed, to make it easy for an operator to perform a preliminary work before measurement. When the operator selects one desired measurement type among a plurality of measurement types in a selection window, there is displayed on the display, depending on the selected measurement type, graphical information about necessary optical parts which should be newly installed and/or installed optical parts which should be removed. The operator looks at the operating instructions and then performs the replacement work. The graphical information may be: graphical indication of the installation locations of the optical parts; different pictorial expressions about the installation and the removal works; and graphical indication of the identification marks of the optical parts.

Abstract: The present invention effectively produces glucose dehydrogenase derived from Aspergillus oryzae, and provides more practical glucose dehydrogenase. The invention makes it possible to efficiently produce glucose dehydrogenase and to obtain glucose dehydrogenase in more practical manner by using a glucose dehydrogenase gene isolated from Aspergillus oryzae.

Abstract: The present invention provides a method for highly expressing a recombinant FAD-GDH protein derived from filamentous fungi, protein obtained by the method, and a regent for measuring glucose using the protein. According to the invention, the FAD-GDH can be highly expressed by altering DNA sequence coding for a signal peptide of FAD-GDH gene isolated from Aspergillus oryzae. FAD-GDH can be stably produced by adjusting pH of 7.1 to 7.3 during culture production.

Abstract: The present invention relates to a method for enhancing stability of a composition comprising soluble glucose dehydrogenase (GDH). Soluble GDH is preferably FAD-dependent GDH derived from filamentous fungus, and the best effect is observed in FAD-GDH derived from A. oryzae or FAD-GDH derived from A. terreus. According to the invention, in a composition comprising soluble glucose dehydrogenase (GDH), stability of GDH can be enhanced by coexisting the enzyme with one or more compounds selected from amino acids and sugars which are not substrate of the enzyme, thus expected to enhancing a measurement accuracy of glucose.