小麦液泡膜H⁺-ATPase的Ca²⁺激活特性

小麦液泡膜H + -ATPase的Ca 2+ 激活特性 Characterization of Ca 2+ Stimulation of Wheat Tonoplast H + -ATPase 王志强 WANG Zhi\|qiang 1 first-author 赵芳 ZHAO Fang 1 董彩华 DONG Cai\|hua 1 王延枝 WANG Yan\|zhi 1 武汉大学生命科学学院,武汉,430072 武汉大学生命科学学院,武汉,430072 College of Life Sciences,Wuhan University College of Life Sciences,Wuhan University 纯化小麦液泡膜H+ -ATPase,测定了纯化的小麦液泡膜H+ -ATPase 受Mg2+ 和Ca2+ 双重激活的特性及两种激活状态下酶的特性. Mg2+ 激活时酶水解活性受DCCD的抑制,受磷脂酰丝氨酸（PS）影响明显,ATP水解和泵质子活性相偶联.而在Ca2+ 激活时酶水解活性不受DCCD抑制,受PS影响微弱,Ca2+ 激活时ATP水解与泵质子活性解偶联. Mg2+ 和Ca2+ 对小麦液泡膜H+ -ATPase的激活作用不具有叠加效应. The stimulations of wheat tonoplast H +\|ATPase by both Mg 2+ and Ca 2+ were measured on the base of purification of the enzyme. The characterizations of the Mg 2+ \|stimulated and Ca 2+ \|stimulated H +\|ATPase were studied. Mg 2+ \|stimulated H +\|ATPase is inhibited by DCCD, and is greatly affected by PS. ATP hydrolysis and the H + pumping of the Mg 2+ \|stimulated H +\|ATPase are coupled. But the Ca 2+ \|stimulated H +\|ATPase is insensitive to DCCD, and is only slightly affected by PS. ATP hydrolysis and the H + pumping of the Ca 2+ \|stimulated H +\|ATPase are uncoupled. The Mg 2+ stimulation and Ca 2+ stimulation of the wheat tonoplast H +\|ATPase have effects on each other. Ca2+激活 液泡膜H+-ATPase 小麦 Q556 国家自然科学基金!资助项目（39570434） 1999-06-01 2021-04-01 6