Membrane structure: Morphological and chemical alterations in phospholipase-C-treated mitochondria and red cell ghosts.

Phospholipase C fromBacillus cereus was used as a tool for the study of membrane structure. Interference and electron microscopic examination of isolated rat kidney mitochondria and human red blood cell ghosts incubated in the presence of the enzyme revealed that there were discrete areas of digestion on the membranes. These areas were distributed over the surface of the membrane but did not coalesce. These data are interpreted as giving support to the membrane model which postulates that protein does not cover the entire phospholipid layer of the membrane, but that there are areas of the membrane in which the phospholipid polar groups are in direct contact with the outside milieu.