Resistance to oxidative stress caused by ceftazidime and piperacillin in a biofilm of Pseudomonas.

The capacity to form a biofilm was evaluated in Pseudomonas aeruginosa isolated from patients with lung and urinary infections. Adherence, development of microcolonies and slime formation varied in the studied strains. P.

Oxidative stress involved in the antibacterial action of different antibiotics.

Staphylococcus aureus and Escherichia coli sensitive to chloramphenicol incubated with this antibiotic suffered oxidative stress with increase of anion superoxide (O2-). This reactive species of oxygen was detected by chemiluminescence with lucigenin. S.