title: Optimal conditions for the analysis of Pasteurella haemolytica lipopolysaccharide by sodium dodecyl sulphate-polyacrylamide gel electrophoresis.
abstract: The optimal conditions for the analysis of the lipopolysaccharide (LPS) of two serotype A1 isolates and a serotype A2 isolate of Pasteurella haemolytica by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and silver staining were determined. The LPS of the A1 isolates possessed O side chains, consisting of high molecular mass bands with the appearance of a ladder-like pattern, as well as a low molecular mass core-oligosaccharide region; the LPS of the A2 isolate consisted only of the core-oligosaccharide region. Furthermore, the LPS of the two A1 isolates differed in the core-oligosaccharide region. Optimal resolution of low molecular mass LPS components was obtained in a 15% acrylamide resolving gel containing 4 M urea whereas optimal resolution of high molecular mass components was obtained when urea was omitted. Conventional silver staining resulted in excellent visualisation of LPS bands, whereas a modified staining method did not detect additional bands, as has been demonstrated with the LPS of Pseudomonas aeruginosa. Proteinase K digestion of outer membranes gave more clearly defined LPS profiles than did similar digestions of whole cells, and more closely resembled the profiles of purified LPS. With the exception of slight variation in the average molecular mass of a group of O side chains between logarithmic and stationary phases there were no differences in LPS profiles at various stages of the growth cycle; freezing and thawing of LPS samples had no effect on the profiles.
authors.affiliation: Department of Microbiology, University of Glasgow, U.K.
authors.forename: R L
authors.initials: RL
authors.lastname: Davies
authors.forename: Q
authors.initials: Q
authors.lastname: Ali
authors.forename: R
authors.initials: R
authors.lastname: Parton
authors.forename: J G
authors.initials: JG
authors.lastname: Coote
authors.forename: A
authors.initials: A
authors.lastname: Gibbs
authors.forename: J H
authors.initials: JH
authors.lastname: Freer
mesh_terms: D000818:Animals; D000940:Antigenic Variation; D002417:Cattle; D004591:Electrophoresis, Polyacrylamide Gel; D008070:Lipopolysaccharides / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D016978:Mannheimia haemolytica / Q000737:chemistry* / Q000145:classification / Q000254:growth & development; D012703:Serotyping; D016622:Silver Staining; D012967:Sodium Dodecyl Sulfate
chemical_list: D008070:Lipopolysaccharides; D012967:Sodium Dodecyl Sulfate