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Intracellular Trafficking and Translocation of Pertussis Toxin

Ken Teter1

  • 1Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL 32816, USA. kteter@mail.ucf.edu.

Toxins
|July 28, 2019
PubMed

Insights

Pertussis toxin (PT) enters cells and traffics to the ER, where its active subunit unfolds and refolds in the cytosol. This process disrupts cellular signaling by targeting Gi/o proteins.

Area of Science:

  • Microbiology
  • Cell Biology
  • Biochemistry

Background:

  • Pertussis toxin (PT) is a key virulence factor of *Bordetella pertussis*.
  • PT is a multimeric protein complex crucial for bacterial pathogenesis.
  • It targets heterotrimeric Gi/o proteins, disrupting cellular signaling.

Purpose of the Study:

  • To review the intracellular trafficking mechanisms of Pertussis toxin.
  • To elucidate the role of PTS1 subunit unfolding and refolding in PT activity.
  • To understand how PT disrupts cAMP-dependent signaling pathways.

Main Methods:

  • Literature review focusing on cellular and molecular biology studies.
  • Analysis of protein structure and function relevant to toxin activity.
  • Examination of intracellular transport pathways, including endocytosis and ER-associated degradation.

Main Results:

  • PT holotoxin is endocytosed after binding to cell surface glycoconjugates.
  • The active PTS1 subunit is translocated to the cytosol via the ER.
  • PTS1 undergoes order-disorder-order transitions, essential for its ADP-ribosyltransferase activity and signaling disruption.

Conclusions:

  • Intracellular trafficking and conformational changes of PT, particularly PTS1, are critical for its biological activity.
  • Understanding these processes provides insights into toxin mechanisms and host-pathogen interactions.
  • PT's journey from cell entry to cytosolic activation highlights complex cellular pathways exploited by pathogens.

Keywords:
AB toxinERADchaperoneendocytosisendoplasmic reticulumretrograde transporttranslocation

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