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Published on: October 23, 2013

Multi locus sequence typing of Chlamydia reveals an association between Chlamydia psittaci genotypes and host species

Yvonne Pannekoek1, Veerle Dickx, Delphine S A Beeckman

  • 1Department of Medical Microbiology, Academic Medical Center, Amsterdam, The Netherlands.

Plos One
|December 15, 2010
PubMed

Insights

This study reveals a surprising association between Chlamydia psittaci genotypes and host species, challenging previous classifications. A specific Chlamydia psittaci strain grouped with Chlamydia abortus, indicating potential host-driven evolutionary shifts.

Area of Science:

  • Bacteriology
  • Genomics
  • Zoonotic Diseases

Background:

  • Chlamydia are obligate intracellular bacteria causing significant human and animal diseases.
  • Species like C. trachomatis, C. pneumoniae, C. psittaci, and C. abortus have distinct clinical manifestations and hosts.
  • Understanding Chlamydia population structure is crucial for disease control and public health.

Purpose of the Study:

  • To investigate the population structure and genetic diversity of various Chlamydia species.
  • To clarify the phylogenetic relationships between Chlamydia species, particularly C. psittaci and C. abortus.
  • To explore the influence of host species on Chlamydia genotype evolution.

Main Methods:

  • Multi-locus sequence typing (MLST) was employed to analyze 132 Chlamydia isolates.
  • Housekeeping gene fragments were concatenated and analyzed using Neighbour-Joining algorithm and maximum composite likelihood model.
  • Cluster analyses were performed on both concatenated sequences and individual alleles.

Main Results:

  • A Chlamydia psittaci isolate (84/2334) from a parrot clustered with Chlamydia abortus isolates from goats and sheep.
  • This reclassification significantly increased genetic differences between C. psittaci and C. abortus.
  • Chlamydia psittaci genotypes showed association with host species, with evidence of host species jumps.

Conclusions:

  • The study provides the first evidence of an association between Chlamydia psittaci genotypes and host species.
  • Phylogenetic analysis suggests host-driven evolution and potential host-switching events in Chlamydia.
  • These findings necessitate a re-evaluation of Chlamydia taxonomy and host-pathogen dynamics.

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