Alpha-glycated amino acid releasing enzyme

Abstract

The present invention relates to a novel enzyme (α-GARE) which releases an amino acid residue having a glycated α-amino group (α-GA) from a glycated protein etc. and to bacterial strains producing the same. Examples of the bacterial strains include Sphingomonas parapaucimobilis KDK1004 (FERM BP-7041). The α-GARE is contained in the culture supernatant of this strain and α-GA can be released from a glycated peptide by using the same, as shown in FIG. 1.

1 - 25 . cancelled  
     
     
         26 . An isolated enzyme that releases an amino acid having a glycated α-amino group from a glycated protein or a glycated peptide, wherein the enzyme is derived from  Sphingomonas parapaucimobilis.    
     
     
         27 . An enzyme according to  claim 26 , wherein  Sphingomonas parapaucimobilis  is  Sphingomonas parapaucimobilis  KDK 1004 (FERM BP-7041).  
     
     
         28 . An enzyme according to  claim 26 , wherein the amino acid having a glycated α-amino group to be released is valine having a glycated α-amino group.  
     
     
         29 . A method for determining an amount of glycated protein or a glycated peptide in a sample, comprising: 
 (a) degrading a glycated protein or peptide with an enzyme according to  claim 26  to give a degradation product;    (b) performing a redox reaction between the degradation product and a fructosyl amino acid oxidase; and    (c) measuring a product or reactant of the redox reaction to determine the amount of glycated protein or glycated peptide.    
     
     
         30 . A method according to  claim 29 , wherein the product is hydrogen peroxide and an amount of hydrogen peroxide produced by the redox reaction is measured.  
     
     
         31 . A method according to  claim 30 , wherein the amount of hydrogen peroxide produced by the redox reaction is determined by measuring oxidation of a substrate by a peroxidase.  
     
     
         32 . A method according to  claim 31 , wherein the substrate is chromogenic.  
     
     
         33 . A method according to  claim 29 , wherein the reactant is oxygen and an amount of oxygen consumed by the redox reaction is measured.  
     
     
         34 . A method according to  claim 29 , wherein the glycated protein or glycated peptide is glycated hemoglobin.  
     
     
         35 . A kit for determining an amount of glycated protein or glycated peptide, comprising: 
 (a) an enzyme according to  claim 26;     (b) a fructosyl amino acid oxidase;    (c) a peroxidase; and    (d) a substrate that is oxidized by the peroxidase.