Immunochemical and Biologic Studies of the Lipopolysaccharide of Bacteroides Melaninogenicus Subspecies Asaccharolyticus

摘要: Lipopolysaccharide (LPS) was isolated from the outer membrane complex of Bacteroides melaninogenicus by gel chromatography using sodium deoxycholate (NaD), an endotoxin-disaggregating detergent in running buffer. Reaggregation occurred after removal residual NaD. LPS also prepared phenol/water method for comparison. The composed loosely bound lipid (62%) and carbohydrate (32%), with less than 5% protein. Glucose, galactose, glucosamine were major sugars as detected gas-liquid (GLC). Heptose 2-keto-3-deoxyoctonate (KDO) found to be absent when colorimetric tests. Fatty acid analysis GLC disclosed unusual pattern; β-OH myristic notably absent. Biologic activity assessed dermal Shwartzman test, Limulus lysate assay, chick embryo lethality test. preparations gave no positive skin reactions rabbits doses up 1 mg, compared Salmonella typhi 0:901 endotoxin which at 12.5 µg. gelation 30-fold or more different controls. Hemagglutination inhibition (HAI) studies demonstrated presence capsular polysaccharide a contaminant extracted LPS. This could removed partially further purifying ultracentrifugation. B. lacks two core characteristic aerobic Gram-negative endotoxins, has unique fatty composition, displays low biologic potency. These findings may explain rarity septic shock patients infected this organism. contaminating phenol/water-extracted serologic heterogeneity been described previously