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Updated: Aug 29, 2026

Imaging InlC Secretion to Investigate Cellular Infection by the Bacterial Pathogen Listeria monocytogenes
14:05

Imaging InlC Secretion to Investigate Cellular Infection by the Bacterial Pathogen Listeria monocytogenes

Published on: September 19, 2013

Physiological implications of class IIa bacteriocin resistance in Listeria monocytogenes strains

Viveka Vadyvaloo1, Jacky L Snoep1, John W Hastings1

  • 1Department of Biochemistry, University of Stellenbosch, Private Bag X1, 7602 Matieland, South Africa.

Microbiology (Reading, England)
|February 10, 2004
PubMed

Insights

Losing the EIIAB(Man) subunit in Listeria monocytogenes confers bacteriocin resistance. This results in slower growth and glucose consumption but a higher biomass yield, indicating a more efficient metabolic pathway.

Area of Science:

  • Microbiology
  • Bacteriology
  • Food Safety

Background:

  • Class IIa bacteriocins are crucial antimicrobial agents.
  • Resistance to these bacteriocins in Listeria monocytogenes is linked to the absence of the EIIAB(Man) subunit of the mannose-specific phosphotransferase system (PTS).

Purpose of the Study:

  • To investigate the metabolic consequences of EIIAB(Man) absence in Listeria monocytogenes.
  • To understand the trade-offs between bacteriocin resistance and growth characteristics.

Main Methods:

  • Utilized spontaneous resistant (L. monocytogenes B73-MR1) and defined mutant (L. monocytogenes EGDe-mptA) strains lacking EIIAB(Man).
  • Compared specific growth rates, glucose consumption, and biomass yield with wild-type strains (L. monocytogenes B73 and L. monocytogenes EGDe).
  • Analyzed fermentation profiles in the presence of glucose.

Main Results:

  • Bacteriocin-resistant strains exhibited significantly decreased specific growth and glucose consumption rates.
  • These strains demonstrated a significantly higher growth yield compared to wild-type counterparts.
  • A metabolic shift from lactic-acid to mixed-acid fermentation was observed in resistant strains when using glucose.

Conclusions:

  • The absence of EIIAB(Man) reduces glucose transport and growth rate, imposing a cost for bacteriocin resistance.
  • This metabolic alteration leads to a more efficient ATP production per glucose molecule.
  • A higher biomass yield compensates for the reduced growth rate, optimizing energy utilization.

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