小麦液泡膜H^+-ATPase的Ca^(2+)激活特性  

Characterization of Ca^(2+) Stimulation of Wheat Tonoplast H^+-ATPase

作　　者：王志强[1] 赵芳[1] 董彩华[1] 王延枝[1] 

机构地区：[1]武汉大学生命科学学院,武汉430072

出　　处：《武汉大学学报（自然科学版）》1999年第6期841-844,共4页Journal of Wuhan University(Natural Science Edition)

基　　金：国家自然科学基金!资助项目(39570434)

摘　　要：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.

关 键 词：液泡膜 ATPASE 小麦 钙离子 激活作用 质子泵 

分 类 号：S512.101[农业科学—作物学] Q556[生物学—生物化学]