UNIGE document Scientific Article
previous document  unige:74832  next document
add to browser collection

Sputum containing zinc enhances carbapenem resistance, biofilm formation and virulence of Pseudomonas aeruginosa

Que, Yok Ai
Published in Microbial pathogenesis. 2014, vol. 77, p. 36-41
Abstract Pseudomonas aeruginosa chronic lung infections are the leading cause of mortality in cystic fibrosis patients, a serious problem which is notably due to the numerous P. aeruginosa virulence factors, to its ability to form biofilms and to resist the effects of most antibiotics. Production of virulence factors and biofilm formation by P. aeruginosa is highly coordinated through complex regulatory systems. We recently found that CzcRS, the zinc and cadmium-specific two-component system is not only involved in metal resistance, but also in virulence and carbapenem antibiotic resistance in P. aeruginosa. Interestingly, zinc has been shown to be enriched in the lung secretions of cystic fibrosis patients. In this study, we investigated whether zinc might favor P. aeruginosa pathogenicity using an artificial sputum medium to mimic the cystic fibrosis lung environment. Our results show that zinc supplementation triggers a dual P. aeruginosa response: (i) it exacerbates pathogenicity by a CzcRS two-component system-dependent mechanism and (ii) it stimulates biofilm formation by a CzcRS-independent mechanism. Furthermore, P. aeruginosa cells embedded in these biofilms exhibited increased resistance to carbapenems. We identified a novel Zn-sensitive regulatory circuit controlling the expression of the OprD porin and modifying the carbapenem resistance profile. Altogether our data demonstrated that zinc levels in the sputum of cystic fibrosis patients might aggravate P. aeruginosa infection. Targeting zinc levels in sputum would be a valuable strategy to curb the increasing burden of P. aeruginosa infections in cystic fibrosis patients.
Keywords Anti-Bacterial Agents/pharmacologyBiofilms/growth & developmentCarbapenems/pharmacologyDrug Resistance, BacterialHumansMembrane Transport Proteins/metabolismPseudomonas aeruginosa/drug effects/enzymology/growth & development/physiologySignal TransductionSputum/chemistry/microbiologyVirulenceZinc/analysis/metabolism
PMID: 25448466
Full text
Article (Published version) (622 Kb) - document accessible for UNIGE members only Limited access to UNIGE
(ISO format)
MARGUERETTAZ, Mélanie et al. Sputum containing zinc enhances carbapenem resistance, biofilm formation and virulence of Pseudomonas aeruginosa. In: Microbial pathogenesis, 2014, vol. 77, p. 36-41. doi: 10.1016/j.micpath.2014.10.011 https://archive-ouverte.unige.ch/unige:74832

382 hits

0 download


Deposited on : 2015-08-25

Export document
Format :
Citation style :