Heliobacterium chlorum: cell organization and structure

The basic cellular organization of Heliobacterium chlorum is described using the freeze-etching technique. Internal cell membranes have not been observed in most cells, leading to the conclusion that the photosynthetic apparatus of these organisms must be localized in the cell membrane of the bacter...

Full description

Saved in:
Bibliographic Details
Published in:Archives of microbiology 1986-11, Vol.146 (2), p.111-114
Main Authors: MILLER, K. R, JACOB, J. S, SMITH, U, KOLACZKOWSKI, S, BOWMAN, M. K
Format: Article
Language:English
Subjects:
Bacteria - ultrastructure
Bacteriology
Biological and medical sciences
Cell Membrane - ultrastructure
Freeze Etching
Freeze Fracturing
Fundamental and applied biological sciences. Psychology
Microbiology
Microscopy, Electron
Morphology, structure, chemical composition
Photosynthesis
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The basic cellular organization of Heliobacterium chlorum is described using the freeze-etching technique. Internal cell membranes have not been observed in most cells, leading to the conclusion that the photosynthetic apparatus of these organisms must be localized in the cell membrane of the bacterium. The two fracture faces of the cell membrane are markedly different. The cytoplasmic (PF) face is covered with densely packed particles averaging 8 nm in diameter, while the exoplasmic (EF) face contains far fewer particles, averaging approximately 10 nm in diameter. Although a few differentiated regions were noted within these fracture faces, the overall appearance of the cell membrane was remarkably uniform. The Heliobacterium chlorum cell wall is a strikingly regular structure, composed of repeating subunits arranged in a rectangular pattern at a spacing of 11 nm in either direction. We have isolated cell wall fragments by brief sonication in distilled water, and visualized the cell wall structure by negative staining as well as deep-etching.
ISSN:0302-8933
1432-072X
DOI:10.1007/bf00402335