ELECTRON MICROSCOPIC STUDY OF SOME STRAINS OF BACTEROIDES

Abstract

Bladen, Howard A. (National Institute of Dental Research, Bethesda, Md.), and Judith F. Waters . Electron microscopic study of some strains of Bacteroides . J. Bacteriol. 86: 1339–1344. 1963.—Cultures of some unidentified strains of Bacteroides were fixed, and embedded in Vestopal W. Thin sections were cut with a microtome and examined in an electron microscope. A triple-layered cell wall completely encircled the organisms and was separated from the cytoplasmic membrane by a space of 150 to 250 A. This space was crossed by frequent bridges connecting the cell wall to the cytoplasmic membrane. A five-layered cytoplasmic membrane was occasionally observed. However, the outer two dense layers were often difficult to resolve as separate structures and usually appeared as a single thick dense line. Cytokinesis of Bacteroides involved the inward annular growth of the cell wall-cytoplasmic membrane. No cell-plate formation was observed. Intracellular membranous elements occurred in Bacteroides and are reported.