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The transmembrane protein cytochrome <i>c</i> oxidase (C<i>c</i>O) is the terminal oxidase in the respiratory chain of many aerobic organisms and catalyzes the reduction of dioxygen to water. This process maintains an electrochemical proton gradient across the membrane hosting the oxidase. C<i>c</i>O is a well-established model enzyme in bioenergetics to study the proton-coupled electron transfer reactions and protonation dynamics involved in these processes. Its catalytic mechanism is subject to ongoing intense research. Previous research, however, was mainly focused on the turnover of oxygen and electrons in C<i>c</i>O, while studies reporting proton turnover rates of C<i>c</i>O, that is the rate of proton uptake by the enzyme, are scarce. Here, we reconstitute C<i>c</i>O from <i>R. sphaeroides</i> into liposomes containing a pH sensitive dye and probe changes of the pH value inside single proteoliposomes using fluorescence microscopy. C<i>c</i>O proton turnover rates are quantified at the single-enzyme level. In addition, we recorded the distribution of the number of functionally reconstituted C<i>c</i>Os across the proteoliposome population. Studies are performed using proteoliposomes made of native lipid sources, such as a crude extract of soybean lipids and the polar lipid extract of <i>E. coli</i>, as well as purified lipid fractions, such as phosphatidylcholine extracted from soybean lipids. It is shown that these lipid compositions have only minor effects on the C<i>c</i>O proton turnover rate, but can have a strong impact on the reconstitution efficiency of functionally active C<i>c</i>Os. In particular, our experiments indicate that efficient functional reconstitution of C<i>c</i>O is strongly promoted by the addition of anionic lipids like phosphatidylglycerol and cardiolipin.