Characterization of Ca(2+)/H(+) exchange in the plasma membrane of Saccharomyces cerevisiae.
Characterization of Ca(2+)/H(+) exchange in the plasma membrane of Saccharomyces cerevisiae.
复制标题
酿酒酵母质膜中 Ca(2 )/H( ) 交换的表征。
DOI：
10.1016/j.abb.2013.07.005
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发表时间：
2013
影响因子：
3.9
通讯作者：
Xingyu Jiang
中科院分区：
文献类型：
--
作者：
Sha Hong;Xinli Cong;Haiyu Jing;Zhihui Xia;Xi Huang;Xin;Xingyu Jiang
使用水性两相分配方法，在从酵母中分离的功能倒转（内向外）质膜囊泡中直接研究 Ca2+/H+ 交换的特征。结果表明，在产生内部酸性 pH 梯度（荧光猝灭）后，添加 Ca2+ 会导致 H+ 移出囊泡（荧光恢复）。 Ca2+/H+交换显示出相对于质膜中泡外Ca2+和ATP浓度的饱和动力学，并且显示出对Ca2+的特异性。质子载体 FCCP（羰基氰化物-（三氟甲氧基）苯腙）消除了荧光猝灭，从而抑制了质膜囊泡中的 Ca2+/H+ 交换。已知钒酸盐可抑制质膜 H+-ATP 酶，显着降低 Ca2+ 依赖性的 H+ 转运出囊泡。当跨质膜的电势用缬氨霉素和钾消散时，Ca2+/H+交换速率与不含缬氨霉素的对照相比增加，表明该交换的化学计量比大于2H+:Ca2+。这些数据表明，Ca2+ 通过 Ca2+/H+ 交换系统转运出酵母细胞，该系统由质膜 H+-ATP 酶产生的质子动力驱动。
The characteristics of the Ca2+/H+exchange were directly investigated in functionally inverted (inside-out) plasma membrane vesicles isolated from yeast using an aqueous two-phase partitioning method. Results showed that following the generation of an inside-acid pH gradient (fluorescence quenching), addition of Ca2+caused movement of H+out of the vesicles (fluorescence recovery). The Ca2+/H+exchange displayed saturation kinetics with respect to extravesicular Ca2+and ATP concentrations in the plasma membrane, and showed specificity for Ca2+. The protonophore FCCP (carbonyl cyanidep-(trifluoromethoxy) phenylhydrazone), abolished the fluorescence quenching and consequently inhibited Ca2+/H+exchange in plasma membrane vesicles. Vanadate, which is known to inhibit the plasma membrane H+-ATPase, significantly decreased the Ca2+-dependent transport of H+out of vesicles. When the electrical potential across the plasma membrane was dissipated with valinomycin and potassium, the rate of Ca2+/H+exchange increased compared to that of the control without valinomycin, indicating that the stoichiometric ratio for this exchange is greater than 2H+:Ca2+. These data suggest that Ca2+is transported out of yeast cells through a Ca2+/H+exchange system that is driven by the proton-motive force generated by the plasma membrane H+-ATPase.
影响因子：
4
作者：
Cunningham KW
通讯作者：
Cunningham KW
影响因子：
4
作者：
Cui, Jiangjun;Kaandorp, Jaap A.;Ositelu, Olufisayo O.;Beaudry, Veronica;Knight, Alicia;Nanfack, Yves F.;Cunningham, Kyle W.
通讯作者：
Cunningham, Kyle W.