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Peptide translocation across MOMP, the major outer membrane channel from Campylobacter jejuni

Naresh Niranjan Dhanasekar1, Soumeya Aliouane2, Mathias Winterhalter1

  • 1Department of Life Sciences and Chemistry, Jacobs University Bremen, 28719 Bremen, Germany.

Biochemistry and Biophysics Reports
|September 29, 2017
PubMed

Insights

Short poly-arginine peptides can translocate across the outer membrane of Campylobacter jejuni by passing through the major outer membrane protein (MOMP) channel. This study demonstrates peptide transport through a bacterial porin.

Area of Science:

  • Microbiology
  • Biophysics
  • Membrane Protein Research

Background:

  • Campylobacter jejuni possesses a major outer membrane protein (MOMP) crucial for its cell wall structure.
  • Understanding transport mechanisms across the bacterial outer membrane is vital for developing antimicrobial strategies.

Purpose of the Study:

  • To investigate the translocation of short poly-arginine peptides across the Campylobacter jejuni MOMP.
  • To characterize the channel properties of purified MOMP and its interaction with peptides.

Main Methods:

  • Purification of MOMP from a pathogenic C. jejuni strain.
  • Reconstitution of purified MOMP into lipid membranes.
  • Measurement of ion current through MOMP channels.
  • Analysis of peptide-induced current fluctuations and voltage-dependent effects.

Main Results:

  • Purified MOMP formed distinct mono- and trimeric channel populations in lipid membranes.
  • Poly-arginine peptides induced concentration- and voltage-dependent ion current fluctuations.
  • Increased transmembrane potential reduced peptide residence time within the channel.

Conclusions:

  • Poly-arginine peptides are capable of translocating through the Campylobacter jejuni MOMP.
  • MOMP functions as a channel facilitating peptide passage across the bacterial outer membrane.
Keywords:
Campylobacter jejuniLipid bilayerMOMPResidence timeSingle-channel

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