Dr. Stephan Schmitz-Esser
Department of Microbial Ecology
Faculty Center of Ecology
Faculty of Life Sciences
University of Vienna
Althanstr. 14
A-1090 Wien
Austria
 
phone: +43 1 4277 54394
fax: +43 1 4277 54389
email:
 
Genomic and post-genomic analysis of 'Candidatus Amoebophilus asiaticus'
The highly diverse bacterial phylum Bacteroidetes comprises only two major endosymbiont lineages: the first lineage contains the cockroach symbionts Blattabacterium spp. and 'Candidatus Sulcia muelleri', the second lineage comprises the parasitoid wasp symbiont 'Candidatus Cardinium hertigii', and the amoeba symbiont 'Candidatus Amoebophilus asiaticus'. Recently, in collaboration with the US Department of Energy Joint Genome Institute (JGI) the genome sequence of 'Candidatus Amoebophilus asiaticus' 5a2 was determined in the course of the Community Sequencing Program. The genome sequence of provides comprehensive insights into the biology of these symbionts and into mechanisms for interaction with its amoeba host, and paves the way for future post-genomic analyses.
 
 Whole genome analysis of 'Candidatus Amoebophilus asiaticus'
 Genome sequence at JGI

Nucleotide transport proteins in obligate intracellular bacteria
Biological membranes are impermeable for ATP, therefore, carrier proteins are needed for nucleotide transport by obligate intracellular bacteria like chlamydiae and rickettsiae. These bacteria are able to live as energy parasites within their host cells by employing highly specific nucleotide transport proteins (NTT), which import ATP or other nucleotides from the host cell (Neuhaus, 1999). Interestingly, similar transport proteins can be found in the plastids of plants and algae. Phylogenetic analysis of nucleotide transport proteins suggested that ATP/ADP translocases were invented by a chlamydial ancestor and were, after an ancient gene duplication, transferred by lateral gene transfer to rickettsiae and plastids (Greub, 2003; Schmitz-Esser, 2004; Huang, 2007; Tyra, 2007). Recently, in collaboration with  Ilka Haferkamp and Ekkehard Neuhaus (University of Kaiserlautern) we functionally characterized all five NTT proteins from the amoeba symbiont Protochlamydia amoebophila. This analysis revealed that these transporters do not only import DNA and RNA nucleotides but also the electron carrier NAD+ and thus compensate for the inability of Protochlamydia amoebophila to synthesize these compounds de novo (Schmitz-Esser, 2004; Haferkamp, 2004; Haferkamp, 2006).
 
 Nucleotide transport proteins in environmental chlamydiae
 
Publications in peer reviewed journals
  1. Toenshoff ER, Penz T, Narzt T, Collingro A, Schmitz-Esser S, Pfeiffer S, Klepal W, Wagner M, Weinmaier T, Rattei T, Horn M. 2012. Bacteriocyte-associated gammaproteobacterial symbionts of the Adelges nordmannianae/piceae complex (Hemiptera: Adelgidae) ISME J. 6: 384-396.
     PUBMED
  2. Schmitz-Esser S, Penz T, Spang A, Horn M. 2011. A bacterial genome in transition - an exceptional enrichment of IS elements but lack of evidence for recent transposition in the symbiont Amoebophilus asiaticus. BMC Evol. Biol. 11: 270.
     Full text    PUBMED
  3. Knab S, Mushak TM, Schmitz-Esser S, Horn M, Haferkamp I. 2011. Nucleotide parasitism by Simkania negevensis (Chlamydiae). J. Bacteriol. 193: 225-235.
     PUBMED
  4. Penz T, Horn M, Schmitz-Esser S. 2010. The genome of the amoeba symbiont "Candidatus Amoebophilus asiaticus" encodes an afp-like prophage possibly used for protein secretion. Virulence 1: 1-5.
     PUBMED
  5. Schmitz-Esser S, Tischler P, Arnold R, Montanaro J, Wagner M, Rattei T, Horn M. 2010. The genome of the amoeba symbiont 'Candidatus Amoebophilus asiaticus' reveals common mechanisms for host cell interaction among amoeba-associated bacteria. J. Bacteriol. 192: 1045-1057.
     PUBMED
     Supplementary material [PDF]
  6. Ast M, Gruber A, Schmitz-Esser S, Neuhaus HE, Kroth PG, Horn M, Haferkamp I. 2009. Diatom plastids depend on nucleotide import from the cytosol. Proc. Natl. Acad. Sci. USA 106: 3621-3626.
     PUBMED
     Supplementary online material [PDF]
  7. Rinke C, Schmitz-Esser S, Loy A, Horn M, Wagner M, Bright M. 2009. High genetic similarity between two geographically distinct strains of the sulfur-oxidizing symbiont 'Candidatus Thiobios zoothamnicoli' FEMS Microbiol. Ecol. 67: 229-41.
     PUBMED
  8. Schmitz-Esser S, Toenshoff ER, Haider S, Heinz E, Hoenninger VM, Wagner M, Horn M. 2008. Diversity of bacterial endosymbionts of environmental Acanthamoeba isolates. Appl. Environ. Microbiol. 74: 5822-5831.
     PUBMED
     Supplementary material (Table S1)
  9. Schmitz-Esser S, Haferkamp I, Knab S, Penz T, Ast M, Kohl C, Wagner M, Horn M. 2008. Lawsonia intracellularis encodes a functional rickettsia-like ATP/ADP translocase for host exploitation. J. Bacteriol. 190: 5746-5752.
     PUBMED
  10. Maixner F, Wagner M, Lücker S, Pelletier E, Schmitz-Esser S, Hace K, Spieck E, Konrat R, Le Paslier D, Daims H.. 2008. Environmental genomics reveals a functional chlorite dismutase in the nitrite-oxidizing bacterium "Candidatus Nitrospira defluvii". Environ. Microbiol. 10: 3043-3056.
     PUBMED
     Supplementary material
  11. Haferkamp I, Schmitz-Esser S, Wagner M, Neigel N, Horn M, Neuhaus HE. 2006. Tapping the nucleotide pool of the host: novel nucleotide carrier proteins of Protochlamydia amoebophila. Mol. Microbiol. 60: 1534-1545.
     PUBMED
     Supplemental Material
  12. Rinke C, Schmitz-Esser S, Stoecker K, Nussbaumer AD , Molnár DA, Vanura K, Wagner M, Horn M, Ott J, Bright M. 2006. Candidatus Thiobios zoothamnicoli, an ectosymbiotic bacterium covering the giant marine ciliate Zoothamnium niveum. Appl. Environ. Microbiol. 72: 2014-2021.
     PUBMED
  13. Collingro A, Poppert S, Heinz E, Schmitz-Esser S, Essig A, Schweikert M, Wagner M, Horn M. 2005. Recovery of an environmental chlamydia strain from activated sludge by co-cultivation with Acanthamoeba sp. Microbiology 151: 301-309.
     PUBMED
  14. Haferkamp I, Schmitz-Esser S, Linka N, Urbany C, Collingro A, Wagner M, Horn M, Neuhaus HE. 2004. A candidate NAD+ transporter in an intracellular bacterial symbiont related to chlamydiae. Nature 432: 622-625.
     PUBMED
     Supplementary material [PDF]
  15. Horn M, Collingro A, Schmitz-Esser S, Beier CL, Purkhold U, Fartmann B, Brandt P, Nyakatura GJ, Droege M, Frishman D, Rattei T, Mewes HW, Wagner M. 2004. Illuminating the evolutionary history of chlamydiae. Science 304: 728-730.
     PUBMED
     Supplementary material [PDF]
     Press release [PDF]
     Press release (German) [PDF]
     Movie showing environmental chlamydia UWE25 within its amoeba host cells.
        © AAAS/Science. [Windows Media Player]
     Movie showing environmental chlamydia UWE25 within its amoeba host cells.
        © AAAS/Science.[Quicktime]
     Environmental chlamydia genome database
  16. Schmitz-Esser S, Linka N, Collingro A, Beier CL, Neuhaus HE, Wagner M, Horn M. 2004. ATP/ADP translocases: A common feature of obligate intracellular amoebal symbionts related to chlamydiae and rickettsiae. J. Bacteriol. 186: 683-691.
     PUBMED
     ARB/FastA database
  17. Schmid MC, Schmitz-Esser S, Jetten M, Wagner M. 2001. 16S-23S rDNA intergenic spacer and 23S rDNA of anaerobic ammonium oxidizers: implications for phylogeny and in situ detection. Environ. Microbiol. 3: 450-459.

Book chapters and other publications
  1. Horn M, Collingro A, Schmitz-Esser S, Wagner M. 2006. Environmental chlamydia genomics. In Chlamydia: genomics and pathogenesis, pp. 25-44. (Bavoil PM, Wyrick PB, ed.). Horizon Scientific Press, Norfolk.
     Order information
  2. Schmid MC, Schmitz-Esser S, Jetten M, Wagner M. 2001. The rDNA operon of anaerobic ammonium oxidizing bacteria: Implications for phylogeny and in situ detection In Der Stickstoff im Wasser/Abwasser, pp. 7-19. (Metzger J W, ed.). Oldenbourg Industrieverlag GmbH, München.
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