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Forward Genetic Approaches in Chlamydia trachomatis
09:03

Forward Genetic Approaches in Chlamydia trachomatis

Published on: October 24, 2013

Low-nutrient induction of abnormal chlamydial development: a novel component of chlamydial pathogenesis?

A M Coles1, D J Reynolds, A Harper

  • 1Microbial Molecular Genetics and Cell Biology Group, School of Biological Sciences, University of Birmingham, UK.

FEMS Microbiology Letters
|January 15, 1993
PubMed

Insights

Amino acid deprivation causes aberrant intracellular development in chlamydiae, leading to non-cultivable forms. Restoring amino acids reverses these changes, suggesting a mechanism for chlamydial persistence.

Area of Science:

  • Microbiology
  • Cell Biology
  • Infectious Diseases

Background:

  • Chlamydiae are obligate intracellular bacteria with complex developmental cycles.
  • Understanding factors influencing chlamydial development is crucial for controlling infections.

Purpose of the Study:

  • To investigate the impact of amino acid deprivation on the intracellular development of Chlamydia trachomatis and Chlamydia psittaci.
  • To explore the potential role of amino acid deficiency in the formation of non-cultivable chlamydial forms.

Main Methods:

  • McCoy cells were incubated in Eagle's minimal essential medium with varying amino acid concentrations.
  • Intracellular chlamydial development was assessed using fluorescence microscopy, electron microscopy, and infectivity titration.
  • Specific analysis of Chlamydia trachomatis L2 strain 434 response to graded amino acid reductions.

Main Results:

  • Amino acid deprivation induced aberrant intracellular development, producing abnormal reticulate and elementary body forms.
  • Reduced amino acid concentrations correlated with decreased infectivity and increased morphological abnormalities.
  • Restoration of amino acids led to the reversion of inclusions to normal morphology and reappearance of infectious forms.

Conclusions:

  • Amino acid deprivation can lead to aberrant chlamydial development, potentially explaining non-cultivable forms observed in vivo.
  • Tryptophan deprivation, possibly mediated by interferon gamma, may induce these aberrant developmental changes.

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