An enzymatic method for the determination of hemoglobinA(1C).
Fructosyl peptide oxidase is a flavoenzyme that catalyzes the oxidative deglycation of N-(1-deoxyfructosyl)-Val-His, a model compound of hemoglobin (Hb)A(1C). To develop an enzymatic method for the measurement of HbA(1C), we screened for a proper protease using N-(1-deoxyfructosyl)-hexapeptide as a substrate. Several proteases, including Neutral protease from Bacillus polymyxa, were found to release N-(1-deoxyfructosyl)-Val-His efficiently, however no protease was found to release N-(1-deoxyfructosyl)-Val. Neutral protease also digested HbA(1C) to release N-(1-deoxyfructosyl)-Val-His, and then the fructosyl peptide was detected using fructosyl peptide oxidase. The linear relationship was observed between the concentration of HbA(1C) and the absorbancy of fructosyl peptide oxidase reaction, hence this new method is a practical means for measuring HbA(1C.).
Hirokawa
Kozo
K
Research and Development Division, Kikkoman Corporation, 399 Noda, 278-0037, Noda-city, Chiba Pref., Japan. khirokawa@mail.kikkoman.co.jp
Shimoji
Kazuhiko
K
Kajiyama
Naoki
N
D000594:Amino Acid Oxidoreductases / Q000737:chemistry*; D001407:Bacillus / Q000201:enzymology*; D001426:Bacterial Proteins / Q000737:chemistry*; D001681:Biological Assay; D004151:Dipeptides / Q000032:analysis; D010450:Endopeptidases / Q000737:chemistry*; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D010084:Oxidation-Reduction; D012680:Sensitivity and Specificity
D000594:Amino Acid Oxidoreductases; D001426:Bacterial Proteins; D004151:Dipeptides; D010450:Endopeptidases; D006442:Glycated Hemoglobin; C103012:amadoriase; C065481:Bacillus polymyxa proteinase