Raman microspectroscopy reveals long-term extracellular activity of chlamydiae
- Author(s)
- Susanne Haider, Michael Wagner, Markus Christian Schmid, Barbara Susanne Sixt, Jan G. Christian, Georg Häcker, Peter Pichler, Karl Mechtler, Albert Müller, Christian Baranyi, Elena Tönshoff, Jacqueline Montanaro-Punzengruber, Matthias Horn
- Abstract
The phylum Chlamydiae consists exclusively of obligate intracellular bacteria. Some of them are formidable pathogens of humans, while others occur as symbionts of amoebae. These genetically intractable bacteria possess a developmental cycle consisting of replicative reticulate bodies and infectious elementary bodies, which are believed to be physiologically inactive. Confocal Raman microspectroscopy was applied to differentiate between reticulate bodies and elementary bodies of Protochlamydia amoebophila and to demonstrate in situ the labelling of this amoeba symbiont after addition of isotope-labelled phenylalanine. Unexpectedly, uptake of this amino acid was also observed for both developmental stages for up to 3 weeks, if incubated extracellularly with labelled phenylalanine, and P. amoebophila remained infective during this period. Furthermore, P. amoebophila energizes its membrane and performs protein synthesis outside of its host. Importantly, amino acid uptake and protein synthesis after extended extracellular incubation could also be demonstrated for the human pathogen Chlamydia trachomatis, which synthesizes stress-related proteins under these conditions as shown by 2-D gel electrophoresis and MALDI-TOF/TOF mass spectrometry. These findings change our perception of chlamydial biology and reveal that host-free analyses possess a previously not recognized potential for direct experimental access to these elusive microorganisms.
- Organisation(s)
- Department of Biochemistry and Cell Biology
- External organisation(s)
- Technische Universität München, Albert-Ludwigs-Universität Freiburg, Vienna BioCenter
- Journal
- Molecular Microbiology
- Volume
- 77
- Pages
- 687-700
- No. of pages
- 14
- ISSN
- 0950-382X
- DOI
- https://doi.org/10.1111/j.1365-2958.2010.07241.x
- Publication date
- 2010
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 106023 Molecular biology
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/f27db1c5-9c4b-4c59-9473-7111d4d92c2c