The Reversible Interaction of Sodium Dodecyl Sulfate with Bacterial Chromatophores.

The interaction of detergents with photosynthetic systems was studied early by Emil Smith (l), who pointed out the utility of anionic detergents for dispersing chloroplast material. Smith obtained what appeared to be subunits of the pigment complex, and characterized these components by ultracentrifugation. Subsequently, a number of investigators have studied the enzymatic capabilities of chloroplasts treated with detergents; generally, such preparations proved to be either photochemically inactive or to have greatly altered activity. For example, Ke and Clendenning (2) found that very low concentrat.ions of sodium dodecyl sulfate completely destroyed the activity of chloroplasts in Hill reaction assays. Nieman and Vennesland (3), Chiba and Okayama (4), and Kok, Hoch, and Cooper (5) showed that chloroplasts treated with detergents carried out photooridase reactions which appeared to be segments or alterations of the photochemical electron transport syst,em. Recently, with the use of chromatophores of Rhodospirillum rubrum, an energy-linked process was described that rendered these particles resistant to detergent action (6). This observation indicated that operation of the photochemical electron transport system could alter the physical state of the particles, a possibility which has been explored in the present study. This work has also provided a means of reversibly inactivating certain photochemical systems in the bacterial particles.