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Chlamydia attachment to mammalian cells requires protein disulfide isomerase

Carolyn G Conant1, Richard S Stephens

  • 1Division of Infectious Diseases, School of Public Health, 140 Earl Warren Hall, University of California, Berkeley, CA 94720, USA.

Cellular Microbiology
|August 24, 2006
PubMed

Insights

Researchers discovered that protein disulfide isomerase (PDI) on the host cell surface is crucial for Chlamydia infection. Restoring PDI function in a mutant cell line re-enabled bacterial attachment and entry, highlighting PDI

Area of Science:

  • Cell Biology
  • Microbiology
  • Pathogenesis Research

Background:

  • Chlamydia is an intracellular human pathogen requiring host cell invasion for survival and pathogenesis.
  • Molecular mechanisms of Chlamydia binding and entry into mammalian cells remain poorly understood.
  • Genetic manipulation of Chlamydia is challenging, necessitating host-targeted experimental strategies.

Purpose of the Study:

  • To investigate the molecular basis of Chlamydia attachment and entry into host cells.
  • To identify host factors involved in Chlamydia infection using a mutant cell line.

Main Methods:

  • Utilized proteomic analysis to identify defects in a Chlamydia-resistant mutant cell line (CHO6).
  • Assessed Chlamydia trachomatis binding and infectivity following complementation with full-length protein disulfide isomerase (PDI).
  • Evaluated the role of cell-surface PDI in diphtheria toxin entry.

Main Results:

  • The CHO6 cell line exhibited a defect in the processing of the leader sequence for protein disulfide isomerase (PDI).
  • Complementation with PDI restored Chlamydia trachomatis binding and infectivity in the CHO6 mutant cells.
  • Cell-surface PDI was also found to be essential for diphtheria toxin entry.

Conclusions:

  • Native protein disulfide isomerase (PDI) at the cell surface is essential for effective Chlamydia attachment and host cell invasion.
  • PDI plays a critical role in mediating the entry of Chlamydia into mammalian cells.
  • This finding provides a novel host-targeted mechanism for controlling Chlamydia infections.

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