Argüelles J C, Gacto M
Departamento de Microbiologia, Facultad de Biologia, Universidad de Murcia, Spain.
Microbiologia. 1986 Oct;2(2):105-14.
Candida utilis ATCC 60459 contains two intracellular trehalase enzymes clearly distinguishable by molecular weight, behaviour in ion-exchange chromatography and kinetic properties. The high molecular weight trehalase (500 kDa trehalase) is specifically inhibited by acetate and accounts for less than 30% of the total trehalase activity found in cell extracts. The smaller trehalase (280 kDa trehalase) exists mostly as a cryptic enzyme whose activity can be postranslationally activated by cAMP-dependent phosphorylation. The enzyme activity of the 280 kDa trehalase is strongly inhibited by Zn2+ and markedly enhanced in the presence of Ca2+ and Mn2+. The activation by these cations, contrariwise to that induced by ATP and cAMP, does not imply a covalent modification of the 280 kDa enzyme. Several parameters have been determined for both enzymes. The 280 kDa enzyme has the properties shown by the so-called regulatory trehalases whereas the 500 kDa enzyme presents characteristics of a nonregulatory type of trehalase.
产朊假丝酵母ATCC 60459含有两种胞内海藻糖酶，它们在分子量、离子交换色谱行为和动力学性质上有明显区别。高分子量海藻糖酶（500 kDa海藻糖酶）被乙酸盐特异性抑制，在细胞提取物中发现的总海藻糖酶活性中占比不到30%。较小的海藻糖酶（280 kDa海藻糖酶）大多以一种隐蔽酶的形式存在，其活性可通过cAMP依赖性磷酸化进行翻译后激活。280 kDa海藻糖酶的酶活性受到Zn2+的强烈抑制，在Ca2+和Mn2+存在时显著增强。与ATP和cAMP诱导的激活相反，这些阳离子的激活并不意味着280 kDa酶发生了共价修饰。已经测定了这两种酶的几个参数。280 kDa酶具有所谓调节性海藻糖酶所表现出的特性，而500 kDa酶呈现出非调节型海藻糖酶的特征。
