Li S, Yang H P, Zhou H M
Department of Biological Science and Biotechnology, Tsinghua University, Beijing, China.
J Pept Res. 1998 Jan;51(1):45-8.
Yeast invertase exists in two different forms. The cytoplasmic enzyme is non-glycosylated, whereas the external invertase contains approximately 50% carbohydrate of the high mannose type. In this paper, the inactivation and the conformational changes of the yeast external invertase are analyzed for unfolding in urea and guanidinium chloride. The results show that much lower concentrations of denaturants are required to bring about inactivation than are required to produce significant conformational changes of the yeast external invertase. The results suggest that the active sites of the external invertase containing carbohydrate residues may display more conformational flexibility than the enzyme molecules as a whole.
酵母转化酶以两种不同形式存在。胞质酶是非糖基化的，而胞外转化酶含有约50%的高甘露糖型碳水化合物。本文分析了酵母胞外转化酶在尿素和氯化胍中展开时的失活和构象变化。结果表明，导致失活所需的变性剂浓度远低于引起酵母胞外转化酶显著构象变化所需的浓度。结果表明，含有碳水化合物残基的胞外转化酶的活性位点可能比整个酶分子表现出更大的构象灵活性。
