Detection of submicrogram quantities of Escherichia coli lipopolysaccharides by agarose-gel electrophoresis.
A sensitive agarose-gel electrophoresis method has been developed for the visualization of lipopolysaccharide (LPS) samples from several Escherichia coli serotypes, such as 026:B6, 055:B5, 0128:B12, 0111:B4, 0127:B8, and K235. This method can detect as little as 0.5-6 microg of LPS depending on the serotype by treatment of the plates with toluidine blue, and it is able to measure sub-microgram amounts of samples, approx. 0.05-0.5 microg, when the staining with toluidine blue followed by Stains-All procedure is adopted. Treatment of LPS with alkali under anhydrous conditions removes the ester-linked fatty acids and the phosphate groups of the Lipid A component, producing the detoxified LPS. The carbohydrate neutral moiety obtained from the hydrolysate does not migrate during electrophoresis. This was utilized to monitor quantitatively the removal process of the Lipid A component for the formation of the detoxified LPS.
Maccari
Francesca
F
Department of Biologia Animale, University of Modena and Reggio Emilia, 41100 Modena, Italy.
Volpi
Nicola
N
D004396:Coloring Agents / Q000737:chemistry; D004587:Electrophoresis, Agar Gel / Q000379:methods*; D004926:Escherichia coli / Q000737:chemistry* / Q000145:classification; D008050:Lipid A / Q000032:analysis / Q000737:chemistry; D008070:Lipopolysaccharides / Q000032:analysis* / Q000302:isolation & purification; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012703:Serotyping; D014048:Tolonium Chloride / Q000737:chemistry
D004396:Coloring Agents; D008050:Lipid A; D008070:Lipopolysaccharides; D014048:Tolonium Chloride