G. Geis et al., ULTRASTRUCTURE AND BIOCHEMICAL-STUDIES OF THE FLAGELLAR SHEATH OF HELICOBACTER-PYLORI, Journal of Medical Microbiology, 38(5), 1993, pp. 371-377
Helicobacter pylori flagellar sheaths were isolated by sucrose density
-gradient centrifugation and analysed by electronmicroscopy, SDS-PAGE
and gas-liquid chromatography. Electronmicroscopy of thin sections of
flagella showed an internal electron-dense filament and a surrounding
flagellar sheath with the typical bilayer structure of a membrane. The
flagellar filaments could be disintegrated by acid treatment and the
resulting isolated flagellar sheaths formed vesicles, sometimes with c
haracteristic structures. Centrifugation of flagellar preparations aft
er acid treatment resulted in the enrichment of flagellar sheaths in t
he pellet. SDS-PAGE analysis of the pellet showed a reduction of the f
lagellin band and a number of protein bands of 150,76,67,65,53,51,49,2
9.5,18,17 and 16 kDa. However, there were no major protein bands chara
cteristic for the sheath. Differences between the protein profiles of
Sarkosyl-insoluble membranes and flagellar sheaths appeared in the low
er M(r) range of 30-14 kDa. Major fatty acids of isolated flagellar sh
eaths were C 14:0, C 19:0 cyc, C 18:0, and the LPS-specific fatty acid
s 3-OH C 16:0 and 3-OH C 18:0. The results demonstrate that the flagel
lar sheaths of H. pylori are membranes and contain LPS and proteins.