Biofilm culture of Pseudomonas aeruginosa expressing lux genes as a model to study susceptibility to antimicrobials.
A simple in vitro model for culture of biofilm populations of self-bioluminescent Pseudomonas aeruginosa was used for real-time monitoring of the effects of ciprofloxacin. Biofilms of these organisms were established within Sorbarod filters, perfused with a chemically defined simple salts medium. The biofilm population was shown to achieve a pseudo-steady state which was reproducible and stable over several days. The viability of membrane-associated and eluted cells was assessed by spread plate viable counts and by monitoring bioluminescence as a measure of metabolic activity. Pseudo-steady state biofilms were exposed to 5x MIC ciprofloxacin (0.3 mg x l(-1)) in the perfusing medium for 1 h. Whilst both methods for viability assessment indicated an immediate reduction in viable cell numbers, the decline recorded with bioluminescence was greater. The use of bioluminescent bacteria proved to be a rapid and sensitive method for the measurement of real-time antibacterial effects on a bacterial biofilm.
Parveen
A
A
Department of Biological and Biomedical Science, University of the West of England, BS16 1QT, Bristol, UK.
Smith
G
G
Salisbury
V
V
Nelson
S M
SM
D000890:Anti-Infective Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D002939:Ciprofloxacin / Q000494:pharmacology*; D003470:Culture Media; D008163:Luminescent Measurements; D008826:Microbial Sensitivity Tests / Q000379:methods; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics / Q000502:physiology*
D000890:Anti-Infective Agents; D001426:Bacterial Proteins; D003470:Culture Media; D002939:Ciprofloxacin