Sone N, Hinkle P C
J Biol Chem. 1982 Nov 10;257(21):12600-4.
Cytochrome oxidase from the thermophilic bacterium PS3 which contains three types of polypeptide subunits are reconstituted into liposomes by a freeze-thaw technique. The reconstituted enzyme caused acidification of the medium during cytochrome c oxidation with a stoichiometry of up to 0.8 H+/e. Uptake of K+ ions in the presence of valinomycin occurred with a stoichiometry between 1.5 and 2 K+/e. Dicyclohexylcarbodiimide inhibited the acidification and decreased the stoichiometry of K+ ion uptake to about 1 K+/e. This bacterial oxidase thus appears to be a proton pump with properties similar to the mitochondrial enzyme.
来自嗜热细菌PS3的细胞色素氧化酶含有三种类型的多肽亚基，通过冻融技术被重组到脂质体中。重组后的酶在细胞色素c氧化过程中导致培养基酸化，化学计量比高达0.8 H⁺/e。在缬氨霉素存在的情况下，K⁺离子的摄取化学计量比在1.5至2 K⁺/e之间。二环己基碳二亚胺抑制了酸化作用，并将K⁺离子摄取的化学计量比降低至约1 K⁺/e。因此，这种细菌氧化酶似乎是一种质子泵，其性质与线粒体酶相似。
