Chlamydiae

Abstract

Chlamydiae are bacterial species with a developmental cycle requiring replication in eukaryotic cells. They infect the cells of mammals, birds, marsupials, fish, reptiles, amphibians, insects and protozoa. The most famous species, Chlamydia trachomatis, causes sexually transmitted disease in humans. Analysis of available genome sequences for these bacterial species has shown that their common ancestor lived over a billion years ago. Because of their diversity, Chlamydiae are often recognised and grouped by using rDNA PCR methods. All Chlamydiae have 16S or 23S ribosomal ribonucleic acid (rRNA) sequences that are at least 80% identical to the rRNA of the Chlamydiaceae family. Chlamydiae are also characterised by four unique phenotypic traits: they have an electron dense infectious form (0.2 μm), they have a morphologically and physiologically distinct replicative form (approximately 1.0 μm), the outer membrane has lipopolysaccharide and is structurally dependent on disulfide‐crosslinked cysteine‐rich proteins, and in host cells Chlamydiae generally are located within membrane‐bound inclusions.

Key Concepts:

  • Chlamydia was long believed to be a simple and mysterious disease.

  • Today we know it is a tiny intracellular bacterium so unique that it is classified at the highest level: phylum Chlamydiae.

  • Chlamydiae probably includes thousands of species.

  • So far (since 1980) 25 chlamydial species have been described in some detail.

  • These species are found in animals, amoebae, insects and a worm living on the bottom of the ocean.

  • The complete genomes of 12 chlamydial species have been DNA sequenced.

  • Genome sequencing reveals that Chlamydiae existed a billion years ago.

  • The common ancestor of all Chlamydiae was directly related to the ancestors of plants and animals and other bacteria.

  • All genome‐sequenced Chlamydiae have 493 genes in common – approximately one quarter to one half of each genome.

  • Chlamydial phenotypes today display the observable effects of these genes.

Keywords: Chlamydia(e); disease; psittacosis; genome; intracellular; bacteria; evolution; amoeba; virus; veterinary

Figure 1.

Chlamydial taxonomy and phylogeny, 2011. Heavy bars=the year the family was named is indicated. Scale bar=‘estimated evolutionary change’; clustal alignment manually refined, Neighbour joining – no filter. Courtesy of Astrid Collingro, Department of Microbial Ecology, University of Vienna.

Figure 2.

The classic Chlamydiales developmental cycle of infection and replication. EB and RB morphological shape variations can include cocci, crescent, bow‐tie, elongated, pear‐shaped, vacuolated and head‐and‐tail. Some species are also found living directly in the cytoplasm. In amoebae some Chlamydiae can survive in cysts. The cycle typically takes 2–3 days, although some species have longer cycles (e.g. Simkaniaceae). EB, elementary body; RB, reticulate body.

Figure 3.

Electron micrograph of Chlamydia pneumoniae in the Alzheimer's brain. Arrows=EBs; arrowheads=RBs; Bar, 0.5 μm. Unpublished, courtesy of Brian J. Balin, Center for Chronic Disorders of Aging, Philadelphia College of Osteopathic Medicine, Philadelphia, PA; Alan P Hudson, Professor of Immunology and Microbiology, Wayne State University, Detroit, MI.

Figure 4.

Cell walls and inclusion wall of intracellular Chlamydiae. COMC, chlamydial outer membrane complex; T3SS, type‐3 secretion system.

Figure 5.

Eukaryotic evolution timescale indicating lineages infected with Chlamydiae (*). The phylogeny is based on SSU rRNA and calibrated using the continuous Phanerozoic microfossil record (Berney and Pawlowski, ). Rectangles delimit 95% confidence intervals. Lineages that host Chlamydiae in order of known frequency of infection: Metazoan>Amoebozoa>Excavates>Alveolates (Casson et al., ; Horn, ; Everett KDE and Meijer A, unpublished).

close

References

Barbour AG, Amano K, Hackstadt T et al. (1982) Chlamydia trachomatis has penicillin‐binding proteins but not detectable muramic acid. Journal of Bacteriology 151: 420–428.

Beeckman DS, Geens T, Timmermans JP et al. (2008) Identification and characterization of a type III secretion system in Chlamydophila psittaci. Veterinary Research 39: 27.

Berney C and Pawlowski J (2006) A molecular time‐scale for eukaryote evolution recalibrated with the continuous microfossil record. Proceedings of the Royal Society of London. Series B 273: 1867–1872.

Bertelli C, Collyn F, Croxatto A et al. (2010) The Waddlia genome: a window into chlamydial biology. PLoS One 5: e10890.

Bodetti TJ, Jacobson E, Wan C et al. (2002) Molecular evidence to support the expansion of the host range of Chlamydophila pneumoniae to include reptiles as well as humans, horses, koalas and amphibians. Systematic and Applied Microbiology 25: 146–152.

Büttner D and He SY (2009) Type III protein secretion in plant pathogenic bacteria. Plant Physiology 150: 1656–1664.

Casson N, Michel R, Müller KD et al. (2008) Protochlamydia naegleriophila as etiologic agent of pneumonia. Emerging Infectious Diseases 14: 168–172.

Clifton DR, Dooley CA, Grieshaber SS et al. (2005) Tyrosine phosphorylation of the chlamydial effector protein Tarp is species specific and not required for recruitment of actin. Infection and Immunity 73: 3860–3868.

Corsaro D and Venditti D (2009) Detection of Chlamydiae from freshwater environments by PCR, amoeba coculture and mixed coculture. Research in Microbiology 160: 547–552.

Eickhoff M, Thalmann J, Hess S et al. (2007) Host cell responses to Chlamydia pneumoniae in gamma interferon‐induced persistence overlap those of productive infection and are linked to genes involved in apoptosis, cell cycle, and metabolism. Infection and Immunity 75: 2853–2863.

Essig A, Heinemann M, Simnacher U et al. (1997) Infection of Acanthamoeba castellanii by Chlamydia pneumoniae. Applied and Environmental Microbiology 63: 1396–1399.

Everett KDE, Bush RM and Andersen AA (1999) Emended description of the order Chlamydiales, proposal of Parachlamydiaceae fam. nov. and Simkaniaceae fam. nov., each containing one monotypic genus, revised taxonomy of the family Chlamydiaceae, including a new genus and five new species, and standards for the identification of organisms. International Journal of Systematic Bacteriology 49: 415–440.

Fukushi H and Hirai K (1992) Proposal of Chlamydia pecorum sp. nov. for Chlamydia strains derived from ruminants. International Journal of Systematic Bacteriology 42: 306–308.

Grayston JT, Kuo C‐C, Campbell LA et al. (1989) Chlamydia pneumoniae sp. nov. for Chlamydia sp. strain TWAR. International Journal of Systematic Bacteriology 39: 88–90.

Greub G and Raoult D (2003) History of the ADP/ATP‐translocase‐encoding gene, a parasitism gene transferred from a Chlamydiales ancestor to plants 1 billion years ago. Applied and Environmental Microbiology 69: 5530–5535.

Haider S, Wagner M, Schmid MC et al. (2010) Raman microspectroscopy reveals long‐term extracellular activity of Chlamydiae. Mololecular Microbiology 77: 687–700.

Halberstaedter L and von Prowazek S (1907) Über Zelleinschlüsse parasitärer Natur beim Trachom. Arbeiten aus dem Kaiserlichen Gesundheitsamte (Berlin, Deutschland) 26: 44–47.

Heinmets F and Golub OJ (1948) Observations on the growth of psittacosis virus in chorioallantoic membranes by electron microscope. Journal of Bacteriology 56: 509–525.

Heinz E, Pichler P, Heinz C et al. (2010a) Proteomic analysis of the outer membrane of Protochlamydia amoebophila elementary bodies. Proteomics 10: 4363–4376.

Heinz E, Rockey DD, Montanaro J et al. (2010b) Inclusion membrane proteins of Protochlamydia amoebophila UWE25 reveal a conserved mechanism for host cell interaction among the Chlamydiae. Journal of Bacteriology 192: 5093–5102.

Horn M (2008) Chlamydiae as symbionts in eukaryotes. Annual Review of Microbiology 62: 113–131.

Horn M, Collingro A, Schmitz‐Esser S et al. (2004) Illuminating the evolutionary history of chlamydiae. Science 304: 728–730.

Horn M, Wagner M, Müller KD et al. (2000) Neochlamydia hartmannellae gen. nov., sp. nov. (Parachlamydiaceae), an endoparasite of the amoeba Hartmannella vermiformis. Microbiology 146: 1231–1239.

Huang J and Gogarten JP (2007) Did an ancient chlamydial endosymbiosis facilitate the establishment of primary plastids? Genome Biology 8: R99.

Huang J and Gogarten JP (2008) Concerted gene recruitment in early plant evolution. Genome Biology 9: R109.

Hueck CJ (1998) Type III protein secretion systems in bacterial pathogens of animals and plants. Microbiology and Molecular Biology Reviews 62: 379–433.

Keeling PJ (2010) The endosymbiotic origin, diversification and fate of plastids. Philosophical Transactions of the Royal Society Biological Sciences 365: 729–748.

Koonin EV, Makarova KS and Aravind L (2001) Horizontal gene transfer in prokaryotes: quantification and classification. Annual Review of Microbiology 55: 709–742.

Lazarus AS and Meyer KF (1939) The Virus of Psittacosis: I, II, and III. Journal of Bacteriology 38: 121–198).

Medini D, Covacci A and Donati C (2006) Protein homology network families reveal step‐wise diversification of Type III and Type IV secretion systems. PLoS Computational Biology 2: e173.

Moulder JW (1966) The relation of the psittacosis group (Chlamydiae) to bacteria and viruses. Annual Review of Microbiology 20: 107–130.

Moustafa A, Reyes‐Prieto A and Bhattacharya D (2008) Chlamydiae has contributed at least 55 genes to Plantae with predominantly plastid functions. PLoS One 3: e2205.

Ochman H, Elwyn S and Moran NA (1999) Calibrating bacterial evolution. Proceedings of the National Academy of Sciences of the USA 96: 12638–12643.

Pallen MJ, Beatson SA and Bailey CM (2005) Bioinformatics, genomics and evolution of non‐flagellar type‐III secretion systems: a Darwinian perspective. FEMS Microbiology Reviews 29: 201–229.

Page LA (1966) Revision of the family Chlamydiaceae Rake (Rickettsiales): unification of the psittacosis‐lymphogranuloma venereum‐trachoma group of organisms in the genus Chlamydia, Jones, Rake and Stearns, 1945. International Journal of Systematic Bacteriology 16: 223–252.

Ramsey KH, Sigar IM, Schripsema JH et al. (2009) Strain and virulence diversity in the mouse pathogen Chlamydia muridarum. Infection and Immunity 77: 3284–3293.

Rocap G, Larimer FW, Lamerdin J et al. (2003) Genome divergence in two Prochlorococcus ecotypes reflects oceanic niche differentiation. Nature 424: 1042–1047.

Seth‐Smith HM, Harris SR, Rance R et al. (2011) Genome sequence of the zoonotic pathogen Chlamydophila psittaci. Journal of Bacteriology 193: 1282–1283.

Skipp P, Robinson J, O'Connor CD et al. (2005) Shotgun proteomic analysis of Chlamydia trachomatis. Proteomics 5: 1558–1573.

Stephens RS, Kalman S, Lammel C et al. (1998) Genome sequence of an obligate intracellular pathogen of humans: Chlamydia trachomatis. Science 282: 754–759.

Storz J and Page LA (1971) Taxonomy of the chlamydiae: reasons for classifying organisms of the genus Chamydia family Chlamydiaceae, in a separate order, Chlamydiales ord. nov. International Journal of Systematic Bacteriology 21: 332–334.

Takano H and Takechi K (2010) Plastid peptidoglycan. Biochimica et Biophysica Acta 1800: 144–151.

Taylor HR (2008) Trachoma: A Blinding Scourge. Australia: Haddington Press/Centre for Eye Research.

Thygeson P (1962) Trachoma virus: historical background and review of isolates. Annals of the New York Academy of Sciences 98: 6–13.

Vandahl BB, Birkelund S, Demol H et al. (2001) Proteome analysis of the Chlamydia pneumoniae elementary body [http://www.gram.au.dk]. Electrophoresis 22: 1204–1223.

Weisburg WG, Hatch TP and Woese CR (1986) Eubacterial origin of chlamydiae. Journal of Bacteriology 167: 570–574.

Wyrick PB (2010) Chlamydia trachomatis persistence in vitro: an overview. Journal of Infectious Diseases 201(suppl. 2): S88–S95.

Zhang YX, Fox JG, Ho Y et al. (1993) Comparison of the major outer‐membrane protein (MOMP) gene of mouse pneumonitis (MoPn) and hamster SFPD strains of Chlamydia trachomatis with other Chlamydia strains. Molecular Biology and Evolution 10: 1327–1342.

Further Reading

Collingro A, Tischler P, Weinmaier T et al. (2011) Unity in variety – the pan‐genome of the Chlamydiae. Molecular Biology and Evolution June 20. (Epub ahead of print).

Contact Editor close
Submit a note to the editor about this article by filling in the form below.

* Required Field

How to Cite close
Everett, Karin DE(Jul 2011) Chlamydiae. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0000451.pub2]