| 摘要 |
PURPOSE:To obtain the subject dehydrogenase, directly and selectively reactive with fructose and useful for determining the fructose. CONSTITUTION:This quinone-dependent fructose dehydrogenase is obtained by culturing Acetobacter aceti 1023 (FERM BP-2287), etc., and has the following properties: (1) catalyzing the conversion of D-fructose into a keto-D-fructose by oxidation and having 2.1X10<-3>M value of Km (30 deg.C and pH 5.0); (2) optimum pH: 5.0 and stable at pH 5.0-7.0; (3) optimum action temperature: 10-60 deg.C and having about 45% residual activity by treating at 40 deg.C for 15min; (4) constituted of four proteins respectively having about 57000, about 41000, about 21500 and about 16000 molecular weights obtained from the measurement according to the sodium dodecyl sulfate (SDS)-polyacrylamide electrophoresis and (5) inhibited by heavy metals such as copper, nickel or zinc. |
