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Protein import and export across the bacterial outer membrane.

Jérémy Guérin1, Susan K Buchanan1

  • 1Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, 20892, USA.

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Bacterial outer membranes import large protein toxins via beta-barrel proteins. This review covers bacteriocin import using TonB-dependent transporters and protein secretion by autotransporter and two-partner systems.

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Area of Science:

  • Microbiology
  • Molecular Biology
  • Biochemistry

Background:

  • The bacterial outer membrane is a critical barrier.
  • Transport across this membrane is essential for bacterial survival and interaction.
  • Import/export of large proteins, like toxins, is a complex process.

Purpose of the Study:

  • To review recent progress in understanding large protein transport across the bacterial outer membrane.
  • To summarize mechanisms of bacteriocin import and protein secretion.

Main Methods:

  • Review of existing literature on bacterial outer membrane transport systems.
  • Focus on TonB-dependent transporters, autotransporter systems, and two-partner secretion systems.

Main Results:

  • Detailed explanation of bacteriocin import via TonB-dependent transporters.
  • Description of protein secretion mechanisms employed by autotransporters.
  • Overview of the two-partner secretion system for large protein export.

Conclusions:

  • Significant advancements have been made in elucidating these complex transport pathways.
  • Understanding these systems is crucial for developing novel antibacterial strategies.
  • Bacterial outer membrane transport involves sophisticated protein machinery.