Romeu A, Montero M A, Ruiz J A, De María M J, Jimenez J A, Rojas A, Arola L
University of Rovira i Virgili, Department of Biochemistry and Biotechnology, Tarragona, Spain.
Biochem Mol Biol Int. 1994 Aug;33(5):939-46.
The kinetic parameters of almond beta-glucosidase (beta-D-glucoside glucohydrolase; EC 3.2.1.21), using pNGP as substrate were kM = 2.24 +/- 0.11 mM and Vmax 588 +/- 25.1 U/mg protein. Only Hg(II) and Cu(II) showed irreversible inactivation of the enzyme. However, when these metals were present in the reaction system the inhibition effects were consistent with a mixed-type inhibition pattern (Cu(II) ki: 5.08 mM and Hg(II) ki: 0.07 mM). The glucose kinetic effect was also consistent with a mixed-type inhibition (ki = 406 mM) pattern with pNGP as varied substrate. Ethanol displayed the kinetic pattern of competitive inhibition (ki = 640 mM).
以对硝基苯基-β-D-吡喃葡萄糖苷（pNGP）为底物时，杏仁β-葡萄糖苷酶（β-D-葡糖苷葡糖水解酶；EC 3.2.1.21）的动力学参数为：米氏常数（kM）= 2.24±0.11 mM，最大反应速度（Vmax）= 588±25.1 U/mg蛋白质。只有汞（II）和铜（II）会使该酶发生不可逆失活。然而，当这些金属存在于反应体系中时，抑制作用符合混合型抑制模式（铜（II）的抑制常数（ki）：5.08 mM，汞（II）的抑制常数（ki）：0.07 mM）。以pNGP为可变底物时，葡萄糖的动力学效应也符合混合型抑制（抑制常数（ki）= 406 mM）模式。乙醇表现出竞争性抑制的动力学模式（抑制常数（ki）= 640 mM）。
