PREPARATION AND PROPERTIES OF CELL WALLS OF THE AGENT OF MENINGOPNEUMONITIS

Abstract

Treatment of purified preparations of the agent of meningopneumonitis, a typical member of the psittacosis group of micro-organisms, with deoxycholate and trypsin yielded structures which are regarded as cell walls because they retained the size and shape of the intact particles, contained only traces of nucleic acid, and were almost completely free of electron-dense internal material. The morphological and chemical properties of the cell walls were compared with those of intact particles. Morphologically, the cell walls appeared as collapsed envelopes devoid of the electron-dense masses characteristic of intact particles. Chemically, they were similar to intact particles, but differed from them in having almost no nucleic acid, a different amino acid composition, and less phospholipid. In some chemical properties and in reaction to deoxycholate, meningopneumonitis cell walls resembled those of rickettsiae and gram-negative bacteria.