THE RATE OF ATP-SYNTHESIS AS A FUNCTION OF DELTA-PH AND DELTA-PSI CATALYZED BY THE ACTIVE, REDUCED H+-ATPASE FROM CHLOROPLASTS
THE RATE OF ATP-SYNTHESIS AS A FUNCTION OF DELTA-PH AND DELTA-PSI CATALYZED BY THE ACTIVE, REDUCED H+-ATPASE FROM CHLOROPLASTS
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DOI：
10.1016/0014-5793(91)81447-g
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发表时间：
1991-12-09
期刊：
影响因子：
3.5
通讯作者：
GRABER, P
中科院分区：
文献类型：
--
作者：
JUNESCH, U;GRABER, P
叶绿体中的H⁺ - ATP酶被置于活性的还原态。然后，通过酸碱转换产生质子穿过类囊体膜的电化学势差ΔpH，并结合K⁺ /缬氨霉素扩散电位Δψ。用快速混合猝灭流动装置在20 - 150毫秒的时间范围内测量ATP合成的初始速率。ATP合成速率以S形方式依赖于ΔpH。扩散电位的增加使对ΔpH的依赖向更低的ΔpH值偏移。对数据的分析表明，ATP合成速率取决于质子的电化学势差，而与ΔpH和Δψ的相对贡献无关。
The H+-ATPase from chloroplasts was brought into the active, reduced state. Then, an electrochemical potential difference of protons across the thylakoid membranes was generated by an acid-base transition, DELTA-pH, combined with a K+/valinomycin diffusion potential, DELTA-psi. The initial rate of ATP synthesis was measured with a rapid-mixing quenched-flow apparatus in the time-range between 20-150 ms. The rate of ATP synthesis depends in a sigmoidal way on DELTA-pH. Increasing diffusion potentials shifts the DELTA-pH-dependencies to lower DELTA-pH values. Analysis of the data indicate that the rate of ATP synthesis depends on the electrochemical potential difference of protons irrespective of the relative contribution of DELTA-pH and DELTA-psi.