Archives of Microbiology

, Volume 130, Issue 1, pp 19–22

Bacterial mesosomes: Method dependent artifacts

Authors

  • Hans Rudolf Ebersold
    • Mikrobiologisches Institut der ETH
    • Institut für ZellbiologieElektronenmikroskopie I der ETH
  • Jean-Louis Cordier
    • Mikrobiologisches Institut der ETH
  • Peter Lüthy
    • Mikrobiologisches Institut der ETH
Article

DOI: 10.1007/BF00527066

Cite this article as:
Ebersold, H.R., Cordier, J. & Lüthy, P. Arch. Microbiol. (1981) 130: 19. doi:10.1007/BF00527066

Abstract

The occurrence of mesosomes was investigated during septum formation of vegetative and sporulating cells of Bacillus cereus. It has been demonstrated that bacterial mesosomes which are considered by numerous microbiologists as an integrated constituent of Gram positive bacteria, are in reality artifacts arising during the preparation for electron microscopy. The conventional fixation methods allowed enough time for the cytoplasmic membrane to react to the changed conditions and to form the typical pocket-like membrane invaginations. With cryofixation followed by freeze-substitution it was shown in ultrathin sections that mesosomes do not occur. The extremely rapid freezing and the substitution of the ice by an organic solvent containing the fixative prevented the formation of membraneous artifacts.

Key words

Bacillus cereusMesosomesChemical fixationCryofixationFreeze-substitutionFreeze-fracturing

Non-standard abbreviations

OsO4

osmium tetroxide

UO2Ac

uranylacetate

PHB

poly-β-hydroxy-butyric acid

M

mesosome

CW

cell wall

CM

cytoplasmic membrane

PF

plasmatic fracture of the cytoplasmic membrane

Copyright information

© Springer-Verlag 1981