The virulence factors of Pseudomonas aeruginosa
are under the control of quorum sensing (QS) signals. Hence,
interference with QS prevents its pathogenesis.
The aim of the present research is to assess the influence of some β-lactam antibiotics on cell communication and
the release of different virulence factors.
The minimal inhibitory concentrations of ceftazidime, cefepime and imipenem were evaluated by microbroth dilution
method. The effect of sub-inhibitory concentration of the tested antibiotics on QS signals was investigated using reporter
strain assay. In addition, different virulence factors (elastase, protease, pyocyanin and hemolysin) were estimated in the presence
of their sub-inhibitory concentrations.
Low concentrations of ceftazidime, cefepime and imipenem caused significant elimination of the QS signals 3OHC12-HSL and C4-HSL up to 1/20 MIC. Furthermore, low concentrations of the tested antimicrobials suppressed virulence
factors elastase and hemolysin. Moreover, 1/20 of their MICs reduced elastase, protease, pyocyanin and hemolysin.
Utilization of β-lactam antibiotics at low concentrations could be an effective approach for prevention and treatment
of P. aeruginosa