English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Envelope structure of four gliding filamentous cyanobacteria

Hoiczyk, E., & Baumeister, W. (1995). Envelope structure of four gliding filamentous cyanobacteria. Journal of Bacteriology, 177(9), 2387-2395.

Item is

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Hoiczyk, E.1, Author           
Baumeister, W.1, Author           
Affiliations:
1External Organizations, ou_persistent22              

Content

show
hide
Free keywords: Blue-green alga; Freeze-substitution; Myxococcus-xanthus; Acetobacter-xylinum; Electron-microscopy; Cell-walls; Motility; Ultrastructure; Bacteria; Visualization.; Microbiology.
 Abstract: The cell walls of four gliding filamentous Oscillatoriaceae species comprising three different genera were studied by freeze substitution, freeze fracturing, and negative staining, In all species, the multilayered gramnegative cell wall is covered with a complex external double layer, The first layer is a tetragonal crystalline S-layer anchored on the outer membrane, The second array is formed by parallel, helically arranged surface fibrils with diameters of 8 to 12 nm, These fibrils have a serrated appearance in cross sections, In all cases, the orientation of the surface fibrils correlates with the sense of revolution of the filaments during gliding, i.e., clockwise in both Phormidium strains and counterclockwise in Oscillatoria princeps and Lyngbya aeruginosa, The lack of longitudinal corrugations or contractions of the surface fibrils and the identical appearances of motile and nonmotile filaments suggest that this structure plays a passive screw thread role in gliding, It is hypothesized that the necessary propulsive force is generated by shear forces between the surface fibrils and the continuing flow of secreted extracellular slime, Furthermore, the so-called junctional pores seem to be the extrusion sites of the slime, In motile cells, these pores exhibit a different staining behavior than that seen in nonmotile ones, In the former, the channels of the pores are filled with electron-dense material, whereas in the latter, the channels appear comparatively empty, highly contrasting the peptidoglycan. Finally, the presence of regular surface structures in other gliding prokaryotes is considered an indication that comparable structures are general features of the cell walls of gliding microbes. [References: 49]

Details

show
hide
Language(s):
 Dates: 1995-05
 Publication Status: Issued
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Type: -
 Identifiers: eDoc: 318462
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Journal of Bacteriology
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: -
Pages: - Volume / Issue: 177 (9) Sequence Number: - Start / End Page: 2387 - 2395 Identifier: -