Stephan Schmitz-Esser - Department of Microbial Ecology

	Dr. Stephan Schmitz-Esser Department für Mikrobielle Ökologie Wiener Ökologiezentrum Universität Wien 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 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. PDF PUBMED Supplementary material [PDF] 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. PDF PUBMED Supplementary online material [PDF] 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. PDF PUBMED 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. PDF PUBMED Supplementary material (Table S1) 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. PDF PUBMED 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. PDF PUBMED Supplementary material 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. PDF PUBMED Supplemental Material 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. PDF PUBMED 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. PDF PUBMED 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. PDF PUBMED Supplementary material [PDF] 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. PDF 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 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. PDF PUBMED ARB/FastA database 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. PDF Book chapters and other publications 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. PDF Order information 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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