Structural and Serological Characterization of the O‐Antigenic Polysaccharide of the Lipopolysaccharide from Acinetobacter Strain 90 Belonging to DNA Group 10

Water-soluble lipopolysaccharide (phenol/water extraction) isolated from Acinetobacter strain 90, which belongs to DNA group 10, was hydrolysed with 1% acetic acid, ultracentrifuged, and water-soluble products finally eluted from a Sephadex G-50 column. The major fraction, a polysaccharide, contained D-Gal, D-GlcNAc, D-GalNAc, and 4,6-dideoxy-4-[(R)-3-hydroxybutyramido]-D-galactose (Fuc4NBuOH). The polysaccharide was characterised by means of monosaccharide analyses, Smith-degradation, N-deacetylation/deamination, and NMR studies, and was shown to have a branched pentasaccharide repeating unit. [structure in text] This structure was specifically recognised in western blots and enzyme immunoassays by polyclonal rabbit antisera.