Abstract
Background: Chlamydiae are obligate intracellular bacteria comprising some of the most important bacterial pathogens of animals and humans. Although chlamydial outer membrane proteins play a key role for attachment to and entry into host cells, only few have been described so far. We developed a comprehensive, multiphasic in silico approach, including the calculation of clusters of orthologues, to predict outer membrane proteins using conservative criteria. We tested this approach using Escherichia coli (positive control) and Bacillus subtilis (negative control), and applied it to five chlamydial species; Chlamydia trachomatis, Chlamydia muridarum, Chlamydia (a.k.a. Chlamydophila) pneumoniae, Chlamydia (a.k.a. Chlamydophila) caviae, and Protochlamydia amoebophila.Results: In total, 312 chlamydial outer membrane proteins and lipoproteins in 88 orthologous clusters were identified, including 238 proteins not previously recognized to be located in the outer membrane. Analysis of their taxonomic distribution revealed an evolutionary conservation among Chlamydiae, Verrucomicrobia, Lentisphaerae and Planctomycetes as well as lifestyle-dependent conservation of the chlamydial outer membrane protein composition.Conclusion: This analysis suggested a correlation between the outer membrane protein composition and the host range of chlamydiae and revealed a common set of outer membrane proteins shared by these intracellular bacteria. The collection of predicted chlamydial outer membrane proteins is available at the online database pCOMP http://www.microbial-ecology.net/pcomp and might provide future guidance in the quest for anti-chlamydial vaccines.
| Original language | English |
|---|---|
| Article number | 634 |
| Number of pages | 18 |
| Journal | BMC Genomics |
| Volume | 10 |
| DOIs | |
| Publication status | Published - 29 Dec 2009 |
Funding
The authors would like to thank Christian Baranyi for technical support. This work was supported by the Austrian Science Fund (FWF) grant Y277-B03 and an Austrian Federal Ministry for Science and Research (bmwf) grant in the context of the GEN-AU program. Preliminary sequence data from P. acanthamoebae was obtained from The Institute for Genomic Research. Sequencing of P. acanthamoebae was accomplished with support from the United States National Institute of Health (NIH).
Keywords
- bacterial outer membrane proteins
- chlamydia
