大肠杆菌中的鸟苷酸环化酶。纯化及性质
Guanylate cyclase in Escherichia coli. Purification and properties.
作者信息
Macchia V, Varrone S, Weissbach H, Miller D L, Pastan I
机构信息
Centro di Endocrinologio e Oncologia Spermimentale del Consiglio Nazionale di Richerche II Instituto di Patologia Generale
Roche Institute of Molecular Biology
出版信息
J Biol Chem. 1975 Aug 25;250(16):6214-7.
Guanylate cyclase has been purified from extracts of Escherichia coli. After a 1000-fold purification, the enzyme contains only minor contaminants as judged by disc gel electrophoresis. The Km for GTP is approximately 7 times 10(-5) M and the optimal pH is 8.0. More activity is observed with Mn2+ than with Mg2+, and maximal activity is observed at 0.14 mM Mn2+ and 1.4 mM Mg2+. Based on its behavior on Sephadex G-100, the molecular weight of E. coli guanylate cyclase is about 30,000. Disc gel electrophoretic analysis indicates that the enzyme consists of a single polypeptide chain. Guanylate cyclase does not form 3':5'-AMP from ATP, and therefore, is distinct from adenylate cyclase.
鸟苷酸环化酶已从大肠杆菌提取物中纯化出来。经过1000倍的纯化后，通过圆盘凝胶电泳判断，该酶仅含有少量污染物。GTP的米氏常数约为7×10⁻⁵M，最适pH为8.0。观察到Mn²⁺比Mg²⁺具有更高的活性，在0.14 mM Mn²⁺和1.4 mM Mg²⁺时观察到最大活性。根据其在葡聚糖G - 100上的行为，大肠杆菌鸟苷酸环化酶的分子量约为30,000。圆盘凝胶电泳分析表明该酶由一条多肽链组成。鸟苷酸环化酶不能由ATP形成3':5'-AMP，因此，它与腺苷酸环化酶不同。
Zotero 插件