Abstract
The specific interaction between the exopolysaccharide purified from a number of Pseudomonas aeruginosa isolates from cystic fibrosis patients and a rat lung heparin-lectin was assayed. The polysaccharide prepared from Homma serotypes M, B, I, and G did not act as hapten inhibitors of lectin activity, whereas the polymers prepared from ca. 80% of strains that did not type with Homma serum did act as hapten inhibitors. Inhibition was shown not to be due to lipopolysaccharide. The infrared spectrums of both inhibitory and noninhibitory polymers appeared very similar, although small amounts of glucose and an unidentified amino sugar were found only in the nontypable strains. This evidence suggests that rat lung lectin recognizes and distinguishes a specific type of alginate-like polymer prevalent on the Homma nontypable P. aeruginosa.