Fig 4. ATPase activity of CopB was measured either without (○) or with (●) xenon in the buffer.

A. Solubilized CopB in the presence of 0.1% dodecylmaltoside. B. Solubilized CopB in the presence of 0.1% dodecylmaltoside and 10 μg/ml of soybean phospholipids. C. Reconstituted CopB in proteoliposomes. Each data point represents the release of Pi by 0.337 μg (A, B) or 0.715 μg (C) of CopB. Other details of the measurements were conducted as detailed under Material and methods. The error bars indicate the standard deviation of three independent experiments (n = 3).