Electrophoretic analysis of the lipopolysaccharides of Bacteroides spp.
Lipopolysaccharide (LPS) extracts of reference strains and isolates of Bacteroides spp. prepared by the proteinase K method were resolved by tricine-sodium-dodecyl-sulphate-polyacrylamide gel electrophoresis and located by silver staining. A considerable diversity of LPS profiles was evident within the Bacteroides genus although profiles were essentially species-specific, with some minor interstrain variations apparent among isolates of B. uniformis, B. ovatus, B. eggerthii and B. thetaiotaomicron. The LPS of most species consisted of a major rough LPS component of 2-5 kDa and a series of higher molecular weight bands which varied with species. B. vulgatus LPS was distinctive in showing an extensive ladder of multiple repeating oligosaccharide units with molecular weights ranging from 4 to > 17 kDa B. stercoris LPS included a high molecular weight (> 17 kDa) ladder of repeating oligosaccharide units. B. fragilis and B. thetaiotaomicron differed from most other species in producing a short ladder of repeating oligosaccharide units interspersing the rough LPS and a 5.6 kDa (B. fragilis) or 9 kDa (B. thetaiotaomicron) yellow-staining component. The heterogeneity of LPS profiles within the Bacteroides genus may reflect the differences in pathogenicity among the species and prove useful for typing.
Department of Medical Microbiology, London Hospital Medical College, Whitechapel, UK.
J P
JP
Maskell
D015373:Bacterial Typing Techniques; D001439:Bacteroides / Q000737:chemistry* / Q000145:classification; D004591:Electrophoresis, Polyacrylamide Gel; D008070:Lipopolysaccharides / Q000737:chemistry* / Q000302:isolation & purification; D008970:Molecular Weight; D009844:Oligosaccharides; D013045:Species Specificity
D008070:Lipopolysaccharides; D009844:Oligosaccharides