Groupe de recherche en enzymologie fondamentale et appliquée (GREFA), Département de Chimie, Université du Québec à Montreal, C. P. 8888, Succ. A, Montréal, Québec, Canada, H3C 3P8.
Biotechnol Bioeng. 1991 Apr 15;37(9):854-8. doi: 10.1002/bit.260370909.
This article reports the characterization of the biochemical behavior of glucose oxidase entrapped in polypyrrole. The immobilization of glucose oxidase in a polypyrrole film was performed by entrapment during the electropolymerization of pyrrole at a platinum electrode poised at 0.65 V vs. SCE in aqueous solution in a one-compartment electrochemical cell. Thin films of polypyrrole (0.11 microm) were obtained and the entrapped enzyme obeyed Michaelis kinetics, indicating no diffusional constraints of the substrate. Our results indicate that the entrapped glucose oxidase is more resistant to denaturation conditions such as alkaline pH and temperature (50 and 60 degrees C) than the soluble form of the enzyme. The autoinactivation constant for the entrapped enzyme was also determined in presence of 0.25M of glucose and was 6.19 x 10(-4) min(-1), i.e., corresponding to a half-life value of 20 h. The results reported here show clearly that polypyrrole matrix has a strong stabilizing effect on the stucture and on the activity of glucose oxidase.
本文报道了葡萄糖氧化酶包埋在聚吡咯中的生化行为特征。在一个一室电化学池中，通过在 0.65 V 相对于 SCE 的铂电极上电化学聚合吡咯时包埋，将葡萄糖氧化酶固定在聚吡咯薄膜中。获得了厚度为 0.11 微米的聚吡咯薄膜，并且包埋的酶遵循米氏动力学，表明没有底物的扩散限制。我们的结果表明，与酶的可溶性形式相比，包埋的葡萄糖氧化酶对变性条件（如碱性 pH 和温度（50 和 60°C））更具抗性。在存在 0.25M 葡萄糖的情况下，也确定了包埋酶的自动失活动力学常数，为 6.19 x 10(-4) min(-1)，即半衰期值为 20 小时。这里报道的结果清楚地表明，聚吡咯基质对葡萄糖氧化酶的结构和活性具有很强的稳定作用。
