title: Electron microscopic studies of endotoxins treated with alkaline and acid reagents.
abstract: Endotoxins extracted from Salmonella minnesota wild strain and R mutants (Ra to Re) were treated with two different alkaline reagents. Treatment with diluted sodium hydroxide, which caused partial removal of O-ester linked fatty acids, changed the ultrastructures of endotoxins from an onion-like structure to monolayer particles (approximately 100 A in diameter) except for endotoxic glycolipids from Rd2 and Re mutants which showed mixed ultrastructures of untreated and treated endotoxins. Treatment with alkaline hydroxylamine, which caused liberation of all O-ester linked fatty acids, changed the ultrastructures of all endotoxins to monolayer particles. The results suggested that the ultrastructures of alkaline-treated endotoxins were dependent on the degree of their hydrophobicity. On the other hand, the micrographs of acid treated endotoxins did not show a constant structure because of the high hydrophobicity.
mesh_terms: D000085:Acetates / Q000494:pharmacology; D001427:Bacterial Toxins / Q000302:isolation & purification; D055598:Chemical Phenomena; D002621:Chemistry; D004731:Endotoxins / Q000302:isolation & purification; D004768:Enterotoxins / Q000302:isolation & purification; D006017:Glycolipids / Q000302:isolation & purification; D006851:Hydrochloric Acid / Q000494:pharmacology; D006898:Hydroxylamines / Q000494:pharmacology; D008050:Lipid A; D008070:Lipopolysaccharides / Q000302:isolation & purification; D008854:Microscopy, Electron; D012475:Salmonella; D012972:Sodium Hydroxide / Q000494:pharmacology
chemical_list: D000085:Acetates; D001427:Bacterial Toxins; D004731:Endotoxins; D004768:Enterotoxins; D006017:Glycolipids; D006898:Hydroxylamines; D008050:Lipid A; D008070:Lipopolysaccharides; C027952:salmonella toxin; D012972:Sodium Hydroxide; D006851:Hydrochloric Acid