Coenzyme-binding glucose dehydrogenase

Abstract

The present invention provides a microorganism-derived soluble coenzyme-binding glucose dehydrogenase which catalyzes a reaction for oxidizing glucose in the presence of an electron acceptor, has an activity to maltose as low as 5% or less, and is inhibited by 1,10-phenanthroline. The invention also provides a method for producing the coenzyme-binding glucose dehydrogenase, and a method and a reagent for measuring employing the coenzyme-binding glucose dehydrogenase. According to the invention, the coenzyme-binding glucose dehydrogenase can be applied to an industrial field, and a use becomes possible also in a material production or analysis including a method for measuring or eliminating glucose in a sample using the coenzyme-binding glucose dehydrogenase as well as a method for producing an organic compound. It became also possible to provide a glucose sensor capable of accurately measuring a blood sugar level. Therefore, it became possible to provide an enzyme having a high utility, such as an ability of being used for modifying a material in the fields of pharmaceuticals, clinical studies and food products.

1 - 19 . (canceled) 
   
   
       20 . A biosensor for measuring glucose comprising soluble flavin compound-binding glucose dehydrogenase obtainable from  Aspergillus terreus , or a mutant thereof which results from a deletion, substitution or addition of one amino acid residue, which:
 (a) catalyzes a reaction for oxidizing glucose in the presence of an electron acceptor;   (b) has a 5% or less specific activity to maltose relative to the enzymatic activity to glucose; and   (c) is inhibited by 1,10-phenanthroline.   
   
   
       21 . The biosensor of  claim 20 , wherein ferricyanide is employed at a final concentration of 2 mM to 500 mM.