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Correlation of quorum sensing and virulence factors in Pseudomonas aeruginosa isolates in Egypt

Hamida M Aboushleib1, Hoda M Omar, Rania Abozahra

  • 1Faculty of Pharmacy, Alexandria University, Alexandria, Egypt. h_abou_shleib@yahoo.com.

Journal of Infection in Developing Countries
|October 31, 2015
PubMed
Abstract

Insights

Quorum sensing (QS) genes correlate with virulence factors in Pseudomonas aeruginosa, but QS-deficient strains can still cause infections. Clove oil effectively inhibits QS, offering potential clinical applications.

Area of Science:

  • Microbiology
  • Bacterial Pathogenesis
  • Antimicrobial Research

Background:

  • Pseudomonas aeruginosa is a major cause of hospital-acquired infections.
  • Quorum sensing (QS) controls virulence factors and biofilm formation in P. aeruginosa.
  • Key QS genes include lasR, lasI, rhlR, and rhlI.

Purpose of the Study:

  • To investigate the relationship between specific QS genes and P. aeruginosa virulence factors.
  • To evaluate the potential of clove oil as an inhibitor of QS.

Main Methods:

  • Collected and analyzed 50 P. aeruginosa clinical isolates.
  • Assessed antibiotic susceptibility, biofilm formation, pyocyanin production, and twitching motility.
  • Utilized PCR and sequencing to analyze QS genes (lasR, lasI, rhlR, rhlI).
  • Tested the inhibitory effects of clove oil on virulence factors.

Main Results:

  • Positive correlation observed between biofilm formation and lasR/rhlI genes.
  • Twitching motility correlated positively with lasR, lasI, and rhlI genes.
  • No correlation found between pyocyanin production and the studied QS genes.
  • Identified QS-deficient isolates with point mutations in QS genes, yet still virulent.
  • Clove oil demonstrated significant inhibition of QS-dependent virulence factors.

Conclusions:

  • QS plays a crucial role in P. aeruginosa virulence.
  • QS-deficient isolates can emerge and cause infections.
  • Clove oil shows promise for clinical use in inhibiting P. aeruginosa QS.

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