Properties of yeast cell ghosts obtained by ribonuclease action.

Cell ghosts were obtained from Candida utilis and Saccharomyces cerevisiae by the action of some conformational isomers of pancreatic ribonuclease which passed through the cell wall and penetrated the cell membrane. In the interior, the enzyme caused extensive disorganization of the cellular structure as evidenced by the results of vital staining and electron microscopy. Ribonucleic acid was degraded to fragments that leaked out into the suspending medium. Other cytoplasmic constituents, including the amino acid pool, were released, but most of the cellular protein and deoxyribonucleic acid remained in the ghosts. The lesions in the cytoplasmic membrane were too small to be seen by conventional electron microscopy. The membrane clung to the cell wall even after obliteration of most of the intracellular structure.