Figure 4.

A) Representation of the PhBL reconstituted with F₁F₀‐ATP synthase over an Au electrode. The ATP hydrolysis by F₁F₀ leads to proton pumping across the membrane, which results in a decrease of the pH of the aqueous compartment between the lipid membrane and the Au electrode surface. B) ATP hydrolysis monitored by phosphate production as a function of time for a F₁F₀‐proteoliposome‐modified electrode (black circles) and for a bare liposome‐modified electrode (gray circles). The initial ATP concentration was 150 µm and the temperature was 37 °C. C) The simultaneous proton pumping activity of F₁F₀‐ATP synthase was monitored over time by differential pulse voltammetry (inset). The oxidation peak potential of the SAM on Au is shown as a function of time after ATP hydrolysis started. Error bars=standard deviation of two independent measurements.