Buffering capacity and membrane H+ conductance of Halobacterium halobium.

Buffering capacity and membrane H+ conductance were measured in Halobacterium halobium suspensions in the light and in the dark over a wide range of external pH. The values of both variables for this archaeobacterium were significantly higher than those found for eubacteria in other reports. It appears from our results that the special chemical composition of the cell envelope and the movement of ions, mainly protons, may influence the magnitude of the buffering power and the H+ membrane conductance of these cells.