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Insights on the trafficking and retro-translocation of glycosphingolipid-binding bacterial toxins

Jin A Cho1, Daniel J-F Chinnapen, Emil Aamar

  • 1Division of Gastroenterology and Nutrition, Department of Medicine, Children's Hospital Boston, Boston MA, USA; Department of Pediatrics, Harvard Medical School, Boston, MA, USA.

Frontiers in Cellular and Infection Microbiology
|August 25, 2012
PubMed

Insights

Bacterial toxins like cholera toxin (CT) hijack cell transport to cause disease. Understanding how CT enters cells and unfolds in the ER is key to developing new therapies.

Area of Science:

  • Cellular Biology
  • Microbiology
  • Toxicology

Background:

  • Bacterial toxins and viruses utilize host cell glycosphingolipids for entry and intracellular trafficking.
  • Cholera toxin (CT), a key virulence factor, binds GM1 gangliosides to initiate retrograde transport from the plasma membrane to the endoplasmic reticulum (ER).

Purpose of the Study:

  • To review recent advancements in understanding the molecular mechanisms of bacterial AB(5) toxin pathogenesis.
  • To elucidate how toxins interact with and are sorted by cellular lipid receptors.
  • To detail the processes of toxin unfolding and retro-translocation into the cytosol.

Main Methods:

  • Review of recent scientific literature on bacterial AB(5) toxins.
  • Focus on molecular mechanisms of cellular entry and intracellular trafficking.
  • Analysis of toxin unfolding and retro-translocation pathways.

Main Results:

  • Bacterial toxins exploit glycosphingolipids for cellular entry and trafficking.
  • CT undergoes retrograde transport to the ER, where its A1 subunit unfolds.
  • The CT-A1 polypeptide is retro-translocated to the cytosol via ER-associated degradation (ERAD) pathway components.

Conclusions:

  • Bacterial AB(5) toxins employ sophisticated strategies to hijack host cell machinery.
  • Understanding toxin-cell interactions and intracellular transport is crucial for combating toxin-induced diseases.
  • Further research into ER unfolding and retro-translocation mechanisms can inform therapeutic development.
Keywords:
ERADcholera toxinmembrane traffickingretro-translocation

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