This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Remsen, C. Articles by Lundgren, D. G. Search for Related Content PubMed PubMed Citation Articles by Remsen, C. Articles by Lundgren, D. G.

 Previous Article  |  Next Article 

J Bacteriol. 1966 December; 92(6): 1765-1771
Copyright © 1966 American Society for Microbiology. All Rights Reserved.

Electron Microscopy of the Cell Envelope of Ferrobacillus ferrooxidans Prepared by Freeze-Etching and Chemical Fixation Techniques

Laboratory of Electron Microscopy, Department of General Botany, Swiss Federation Institute of Technology, Zurich, Switzerland
Department of Bacteriology and Botany, Biological Research Laboratories, Syracuse University, Syracuse, New York

ABSTRACT

REMSEN, C. C. (Swiss Federation Institute of Technology, Zurich, Switzerland), AND D. G. LUNDGREN. Electron microscopy of the cell envelope of Ferrobacillus ferrooxidans prepared by freeze-etching and chemical fixation techniques. J. Bacteriol. 92:1765–1771. 1966.—A comparison was made of the fine structure of the cell envelope of the gram-negative bacterium Ferrobacillus ferrooxidans when cells were prepared for microscopy by freeze-etching and chemical fixation techniques. Cell envelopes of chemically fixed cells appeared as five separate layers distinguishable by their location and electron density. Frozen-etched cells showed a three-layered complex with each layer measuring approximately 100 A in thickness. The latter technique is considered to be "artifact-free" and, as a technique, yields purely morphological information on the natural state. The three layers revealed by freeze-etching are: the outer layer, a lipoprotein-lipopolysaccharide layer; the middle layer, a layer composed of globular protein attached to fibrillar mucopeptide; and the innermost layer, the cytoplasmic membrane. The latter was covered with 100 to 120 A particles. The relationship of the aforementioned layers to those seen in chemically fixed cells is discussed.