title: Structural studies on the O-antigen of Aeromonas salmonicida.
abstract: Lipopolysaccharide from a strain of Aeromonas salmonicida salmonicida was isolated from cells by the aqueous phenol method in 2.3% yield (based on dry weight of bacteria). Hydrolysis of the lipopolysaccharide in 1% acetic acid afforded O-polysaccharide (19% by weight), core-oligosaccharide (12.2%) and lipid A (44.6%). Analysis indicated that 3-deoxy-D-manno-2-octulosonic acid was absent from the lipopolysaccharide and that no low-molecular-weight compounds were released by the mild hydrolysis. The O-polysaccharide had the monosaccharide composition of rhamnose, glucose and N-acetylmannosamine in molar ratio of 1.0:1.58:0.83. 75% of the N-acetylmannosamine residues were substituted at position 4 by O-acetyl groups. Hydrolysis of the methylated polysaccharide proved to be both difficult and dependent on the method of hydrolysis chosen, in all cases a partially methylated disaccharide of rhamnose and N-acetylmannosamine was identified in the hydrolysate. Methylation analysis, periodate oxidation and proton magnetic resonance analysis were used to confirm the structure of the repeating unit as: (formula; see text).
mesh_terms: D000333:Aeromonas / Q000276:immunology*; D000942:Antigens, Bacterial / Q000302:isolation & purification*; D055598:Chemical Phenomena; D002621:Chemistry; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D019081:O Antigens; D010084:Oxidation-Reduction; D011135:Polysaccharides, Bacterial / Q000302:isolation & purification
chemical_list: D000942:Antigens, Bacterial; D019081:O Antigens; D011135:Polysaccharides, Bacterial