Antibiotic efflux and permeability resistance mechanisms

Bruxelles Woluwe

We have provioulsy demonstrated the role of active efflux as a mechanism responsible for the intrinsic resistance of P. aeruginosato specific antibiotics, like temocillin, or macrolides.

We have now started to evaluate the ipact of this mechanism of resistance in Achromobacter xylosoxidans, a bacterial species which follows P. aeruginosain the colonization of the lung of patients with cystic fibrosis (CF).

NPN (fluorescent substrate of efflux pumps) accumulation in reference strains and clinical CF isolates of Achromobacteras a function of their AZI/AMK MIC

We could demonstrate that effluxindeed plays a major role in the poor susceptibility of this species to commonly used antibiotics. Importantly, also we could evidence some mutations in these proteins that affect their substrate specificity.