Mechanism of H^+ transport by H^+ATPase

H~(2+)-ATPase转运与ATP水合能量偶联的质子，而ATP合成酶则合成偶联于质子运动的ATP。它们是生物体中最重要的两种基本酶。在本项目中，我们重点研究了FoF_1型ATPase和空泡型ATPase。从广泛的诱变研究中，我们可以发现β亚基的Lys-155、Thr-156、Glu-181和Arg-182正在形成催化位点。我们还可以证明，亚基的Glu-185对于酶的催化协同性是必不可少的。Fo的H~+途径由a、b、c三个亚基组成，a亚基有6个跨膜区，整个Fo具有环状结构。我们研究了一系列亲脂性阳离子对FoF_1-ATPase、液泡型ATPase和氯丙嗪的影响，喹卡林对这两种酶都有抑制作用。我们还显示了刀豆素对空泡型ATPase的抑制作用。

H^+-ATPase transport protons coupling with the energy of ATP hydrosis, and ATP synthase synthesizes ATP coupling with proton movement. They are the two of the most the important basic enzymes in organisms. In this project, we have focused on FoF_1 type ATPase and vacuolar type ATPases.From the extensive mutagenesis studies, we could show Lys-155, Thr-156, Glu-181 and Arg-182 of the beta subunit are forming catalytic site. We also could show that Glu-185 of the subunit is essential for the catalytic cooperativity of the enzyme. The carboxyl and amino terminal helices of the gamma subunit were shown to be essential for energy coupling between catalysis and proton transport.The H^+ pathway of Fo is formed from the a, b, and c subunits we could show that the a subunit has six transmembrane domains and the entire Fo has a ring like structure. We have studied effects of a series of lipophilic cations on FoF_1-ATPase and vacuolar type ATPase and chloropromazine, quinacrine could in habit both enzymes. We also showed inhibitory effects of concanamycin on vacuolar type ATPase.