abstract |
Provided are an amadoriase that is less likely to be influenced by oxygen concentration and a method and a reagent kit for measurement of HbAlc using such amadoriase. Provided are an amadoriase that is obtained via substitution of one or more amino acid residues at a position or positions corresponding to the position(s) selected from the group consisting of positions 280, 267, 269, 54, and 241 of the amadoriase derived from the genus Coniochaeta, a method for measurement of HbA1c, a reagent kit for measurement, and a sensor using such amadoriase. The modified amadoriase according to the invention has a lowered oxidase activity and an enhanced dehydrogenase activity, and this enables the use of an electron mediator, and this reduces the influence of oxygen concentration. Thus, HbAlc can be measured with high sensitivity. |