The Isolation of Two Different Lipopolysaccharide Fractions from Various Proteus mirabilis Strains

Abstract

Four distinct Proteus mirabilis strains were extracted by the phenol/water procedure. After ultra-centrifugation of the dialyzed water phase, the pelleted lipopolysaccharide was purified and analyzed. The sugar composition of this lipopolysaccharide fraction I was similar for all four strains, containing only small amounts of strain-specific constituents. A second lipopolysaccharide fraction was isolated from the supernatant above (termed L1 fraction) after removal of nucleic acids. DEAE-cellulose chromatography indicated that this material is not a polysaccharide but rather a water-soluble lipo-polysaccharide containing strain-specific constituents such as uronic acids, amino acids, amino sugars, neutral sugars, ethanolamine and phosphate, depending on the strain from which lipo-polysaccharide II was isolated.