Analytical characterization of lipopolysaccharide antigens from seven strains of Pseudomonas aeruginosa.

Lipopolysaccharide antigens from seven different serotype strains (antigen immunotypes Nos. 1-7 in the classification of Fisher et al.3) of Pseudomonas aeruginosa have been analyzed for neutral carbohydrate, amino sugars, lipid, protein, 3-deoxy-manno-octulosonic acid, and phosphorus. The individual amino sugars were determined for each antigen type; all contained 2-amino-2-deoxy-D-glucose and -D-galactose, together with 2-amino-2,6-dideoxygalactose; the latter as isolated from the type 2 antigen was identified as the DL form. In addition, 2-amino-2,6-dideoxy-D-glucose was present in the types 3, 4, and 5 antigens. Mild, acid hydrolysis of the antigens gave the lipid A component containing all of the lipid and 2-amino-2-deoxy-D-glucose, together with lipid A-free polysaccharides that contained principally carbohydrate. The lipid A-free polysaccharides all contained L-rhamnose and D-glucose, together with 2-amino-2,6-dideoxygalactose in all except those from types 1, 5, and 7; that from type 6 also contained D-xylose.