title: Characteristics of lipid A-protein complex from endotoxin of Shigella dysenteriae type 1 (S and R strains).
abstract: Mild acetic acid hydrolysis of endotoxin (lipopolysaccharide-protein complex) of Shigella dysenteriae type 1 (S and R forms) yielded a lipid A-protein complex that consisted of amino acids, fatty acids, and sugar and, in terms of chemical composition, displayed no marked differences between the S and R forms. Its protein portion (53 to 56%) consisted of at least 16 amino acids. In the fatty acid portion (14 to 18%), myristic, 3-hydroxymyristic, palmitic, and stearic acids accounted for 50%. The sugar portion (10 to 12%) consisted solely of glucosamine. The remainder was unidentified substances, most of which contained phosphorus. Lipid A-protein complexes derived from both S and R forms were not toxic for mice in doses up to 1,000 microgram/mouse, but their Linulus test activity had increased considerably as compared with the starting lipopolysaccharide-protein complex material: from 10(-6) to 10(-10--10(-12) mg/ml. The lipid A-protein complexes were readily soluble in a water solution of triethylamine, in dimethyl sulfoxide, and in pyridine.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D001426:Bacterial Proteins / Q000032:analysis*; D004731:Endotoxins / Q000032:analysis*; D005227:Fatty Acids / Q000032:analysis; D008033:Limulus Test; D008050:Lipid A / Q000032:analysis*; D008070:Lipopolysaccharides / Q000032:analysis*; D012762:Shigella dysenteriae / Q000032:analysis*; D013045:Species Specificity
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D004731:Endotoxins; D005227:Fatty Acids; D008050:Lipid A; D008070:Lipopolysaccharides