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 jig/mouse, but their Limulus test activity had increased considerably as compared with the starting lipopolysaccharide-protein complex material: from 10-6 to 10-l1010-l2 mg/ml. The lipid A-protein complexes were readily soluble in a water solution of triethylamine, in dimethyl sulfoxide, and in pyridine.Dubois et al. (7).Assay for fatty acids of lipids. The assays for 465 on July 16, 2020 by guest http://iai.asm.org/ Downloaded from

Biological and chemical comparison of butanol‐ and phenol‐water extracted lipopolysaccharide from Capnocytophaga sputigena

“…Cations, nucleic acids, and pep-tides may interfere with the ionic and/or hydrophobic interactions between LPS molecules resulting in a change in the LPS configuration (Shands 1971), which may be the case with C. sputigena BLPS which contained at least 12% protein. The difference in biological activity and morphology between C. sputigena BLPS and PLPS was presumably due to outer membrane proteins which associated with BLPS, similar to that observed in other gramnegative bacteria (i.e., Gmeiner & Schlecht 1980, Russell, Johnson & McDonald 1975, Frasch, McNelis & Gotschlich 1976, Sourek et al 1979. The BLPS proteins of C. sputigena were probably outer membrane proteins with the 39-41 kilodalton band of BLPS ( Fig.…”

Characteristics of a lipid preparation (lipid A) from Haemophilus influenzae type a lipopolysaccharide

“…These lipid preparations typically contain D-glucosamine, fatty acids, phosphate, and often ethanolamine in various proportions (3,15,24). Moreover, identical biological activities are found with various lipid A preparations, although the endotoxins may be extracted from bacteria and purified in various ways (23). Thus, in the LPS molecule, the great diversity of the 0-specific chain contrasts with the lesser variability observed in lipid A.…”