Cell surface changes in Pseudomonas aeruginosa PAO4069 in response to treatment with 6-aminopenicillanic acid

Pseudomonas aeruginosa PAO4096 was induced for beta-lactamases with 6-aminopenicillanic acid. Surface changes concomitant with beta-lactamase induction were monitored. The surface hydrophobicity of the culture increased during exposure to 6-aminopenicillanic acid. The increase was associated with a change in the distribution of the O antigen in the lipopolysaccharide of treated cells. The hydrophobicity change was reversible and partially inhibited by depressed protein synthesis. The susceptibility of induced cells to rifampin was increased transiently, suggesting increased permeability of the induced cells.