A novel cytochrome c oxidase from Rhodobacter sphaeroides that lacks CuA.

Rhodobacter sphaeroides contains at least two different cytochrome c oxidases. When these bacteria are grown with high aeration, the traditional aa 3 -type cytochrome c oxidase is present at relatively high levels. However, under microaerophilic growth conditions or when the bacteria are grown photosynthetically, the amount of the αα 3 -type oxidase is greatly diminished and an alternate cytochrome c oxidase is evident. This alternate oxidase has been purified and characterized. The enzyme consists of three subunits by SDS-PAGE analysis (M app 45, 35, and 29 kDa)