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Quorum sensing-regulated functions of Serratia marcescens are reduced by eugenol

Zahra Fekrirad1, Basira Gattali1, Nasim Kashef1

  • 1Department of Microbiology, School of Biology, College of Sciences, University of Tehran, Tehran, Iran.

Iranian Journal of Microbiology
|February 19, 2021
PubMed
Abstract

Insights

Eugenol effectively reduces biofilm formation and virulence factors in Serratia marcescens by inhibiting quorum sensing (QS). This study highlights eugenol

Area of Science:

  • Microbiology
  • Bacterial Pathogenesis
  • Drug Discovery

Background:

  • Serratia marcescens is a nosocomial pathogen with increasing antibiotic resistance.
  • Quorum sensing (QS) regulates biofilm formation and virulence in S. marcescens.
  • Essential oils show potential against drug-resistant bacteria.

Purpose of the Study:

  • To investigate the effect of eugenol on QS-regulated functions in S. marcescens.
  • To assess eugenol's impact on biofilm formation and virulence factor production.

Main Methods:

  • S. marcescens strains were treated with eugenol at 1.25 and 2.5 µg/ml.
  • Biofilm formation, pigment, hemolysin, and protease production were measured.
  • Gene expression of motility, attachment, biofilm, and QS regulatory genes was analyzed.

Main Results:

  • Eugenol significantly reduced biofilm formation, pigment, hemolysin, and protease production.
  • Eugenol down-regulated genes involved in motility (flhD), attachment (fimC), and biofilm formation (bsmA, bsmB).
  • Expression of the QS regulatory gene (swrR) was significantly reduced by eugenol.

Conclusions:

  • Eugenol effectively inhibits quorum sensing-controlled virulence and biofilm formation in S. marcescens.
  • Eugenol presents a potential therapeutic strategy against S. marcescens infections.
Keywords:
Biofilm formationEugenolQuorum sensingSerratia marcescensVirulence factors

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