A New Metabolic Cell-Wall Labelling Method Reveals Peptidoglycan in Chlamydia Trachomatis

Nature. 2014 Feb 27;506(7489):507-10. doi: 10.1038/nature12892. Epub 2013 Dec 11.


Peptidoglycan (PG), an essential structure in the cell walls of the vast majority of bacteria, is critical for division and maintaining cell shape and hydrostatic pressure. Bacteria comprising the Chlamydiales were thought to be one of the few exceptions. Chlamydia harbour genes for PG biosynthesis and exhibit susceptibility to 'anti-PG' antibiotics, yet attempts to detect PG in any chlamydial species have proven unsuccessful (the 'chlamydial anomaly'). We used a novel approach to metabolically label chlamydial PG using d-amino acid dipeptide probes and click chemistry. Replicating Chlamydia trachomatis were labelled with these probes throughout their biphasic developmental life cycle, and the results of differential probe incorporation experiments conducted in the presence of ampicillin are consistent with the presence of chlamydial PG-modifying enzymes. These findings culminate 50 years of speculation and debate concerning the chlamydial anomaly and are the strongest evidence so far that chlamydial species possess functional PG.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Amino Acids / chemistry
  • Amino Acids / metabolism
  • Cell Wall / chemistry*
  • Cell Wall / metabolism*
  • Chlamydia trachomatis / chemistry*
  • Chlamydia trachomatis / cytology
  • Chlamydia trachomatis / drug effects
  • Chlamydia trachomatis / metabolism
  • Click Chemistry
  • Dipeptides / analysis
  • Dipeptides / chemistry
  • Fluorescence
  • Intracellular Space / chemistry
  • Intracellular Space / metabolism
  • Molecular Probes / analysis
  • Molecular Probes / chemistry
  • Peptidoglycan / analysis*
  • Peptidoglycan / biosynthesis
  • Peptidoglycan / chemistry
  • Peptidoglycan / metabolism
  • Staining and Labeling / methods*


  • Amino Acids
  • Dipeptides
  • Molecular Probes
  • Peptidoglycan