Effect of proteolytic and lipolytic enzymes on the electron transport particle fraction of Rhodospirillum rubrum. II. Phospholipases.

Digestion of the electron transport particle fraction of Rhodospirillum rubrum with the proteases chymotrypsin, trypsin, subtilisin and pronase resulted in a release of protein from the membranal system. The solubilization was, however, limited to only 15 — 18 percent of the total protein, being the same with each of the four proteases. The enzymes catalyzing electron transfer which are located on these particles were not solubilized by the proteolytic digestion but were found to be­ come differently inactivated already with low protease concentrations. The proteolytic attack re­ vealed differences in the specificity of proteolysis