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A major outer-membrane protein functions as a porin in Haemophilus influenzae

J L Burns1, A L Smith

  • 1Department of Pediatrics, University of Washington, Seattle.

Journal of General Microbiology
|May 1, 1987
PubMed

Insights

The 40 kDa outer-membrane protein in Haemophilus influenzae acts as a porin, facilitating molecule entry. Its absence reduces permeability and increases resistance to certain antibiotics.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Bacterial Outer Membranes

Background:

  • Porins are crucial outer-membrane proteins in Gram-negative bacteria.
  • They regulate the passage of hydrophilic molecules.
  • Reduced permeability is often linked to specific outer-membrane protein alterations.

Purpose of the Study:

  • To investigate the function of a 40 kDa outer-membrane protein in Haemophilus influenzae.
  • To determine its role in bacterial permeability and antibiotic resistance.

Main Methods:

  • Comparative analysis of isogenic Haemophilus influenzae strains.
  • Strains with and without the 40 kDa protein were studied.
  • Permeability assays for various molecules (sucrose, raffinose, antibiotics) were performed.

Main Results:

  • Haemophilus influenzae strains lacking the 40 kDa protein exhibited slower growth.
  • These strains showed decreased permeability to sucrose, raffinose, penicillin G, and chloramphenicol.
  • The absence of the protein correlated with increased resistance to multiple hydrophilic antibiotics.

Conclusions:

  • The 40 kDa outer-membrane protein functions as a porin in Haemophilus influenzae.
  • This porin plays a significant role in regulating nutrient uptake and antibiotic susceptibility.
  • Targeting this porin could be a strategy to overcome antibiotic resistance.

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