STRUCTURAL STUDIES OF THE O-ANTIGEN ISOLATED FROM THE PHENOL-SOLUBLE LIPOPOLYSACCHARIDE OF ACINETOBACTER-BAUMANNII (DNA GROUP-2) STRAIN-9

A polysaccharide containing D-GalNAc, D-Glc and 4-acetamido-4,6-dideox y-D-glucose (Qui4NAc) was isolated from the phenol-soluble lipopolysac charide originating from Acinetobacter baumannii strain 9. The structu re of the repeating unit was shown by means of monosaccharide analyses , Smith-degradation, partial acid hydrolysis, mass spectrometry, and N MR spectroscopy to be a branched pentasaccharide, in which the tetrasa ccharide backbone is built from amino sugars only. [GRAPHICS] The poly saccharide was identified by serological and western blot analyses as the O-antigen of the lipopolysaccharide.