VAAM-Jahrestagung 2011 Karlsruhe, 3.–6. April 2011

methods (IS6110-RFLP, 24-MIRU-VNTR and spoligotyping). Drugresistance mutations analysis was apply for rpoB hot-spot, katG315, inhApromoter region, and embB306.Results and Discussion: The availability of the international databaseSITVIT2 permitted us to view our results in the context of the globally andlocally circulating M. tuberculosis clones. Comparison with SITVIT2showed that spoligotype ST53 is found in similar and rather high proportionin the neighboring Greece and Turkey and almost equally distributed acrossdifferent regions of Bulgaria. Contrarily, ST125 is not found elsewhere andis specific for Bulgaria; furthermore it appears to be mainly confined to thesouthern part of the country. Novel 15/24-loci format of MIRU-VNTRtyping was found to be the most discriminatory tool. Three types of the rpoBmutations were found in 20 of 27 RIF-resistant isolates; rpoB S531L was themost frequent. Eleven (48%) of 23 INH-resistant isolates had katG S315Tmutation. inhA -15C>T mutation was detected in one INH-resistant isolateand three INH-susceptible isolates. A mutation in embB306 was found in 7of 11 EMB-resistant isolates. A monoresistance was found in 15 of 37 drugresistantisolates and may be an additional indication of the somewhatinsufficient anti-TB control in Bulgaria.Acknowledgements: This work was partly supported by European SocialFound, Bulgaria, Development of human resources-BG051PO001-3.3.04/32and National Science Fund, Bulgaria,‘Young Researchers'DMU 02/1.[1] WHO-Global tuberculosis control. Geneva, Switzerland. 2010. 2. Brudey, K. et al, 2006.M.tuberculosis complex genetic diversity: mining the fourth international spoligotyping database forclassification, population genetics and epidemiology. BMC Microbiol. 6, 23.MDP025Thermophilic microbial community for methaneproduction at high temperaturesI. Röske*, A. Marks, K. Sahm, G. AntranikianInstitute of Technical Microbiology, University of Technology, Hamburg,GermanyThe development of an efficient and sustainable bioethanol production plantbased on waste biomass requires the integration of various biological andnon-biological processes. After the fermentation of raw wheat straw toethanol and the distillation process large amounts of lignocellulose and yeastcell material remain untreated (stillage). In this project an attempt was madeto identify the microbial community, which is involved in the bioconversionprocess to methane at elevated temperatures (55°C to 70°C). By severalmolecular biological and microbiological methods e.g. Denaturing GradientGel Electrophoresis (DGGE) and 16S rDNA different species of the generaMethanobacterium and Methanosarcina were identified and pure cultureswere isolated. Optimal growth was obtained at a temperature range between55°C and 70°C; most isolates were sensitive to chloramphenicol andrequired hydrogen for growth. The establishment of a robust and definedthermophilic microbial community will contribute to the development of amore efficient biogas production technology. This concept will be developedin collaboration with partners from academia and industry (Biorefinery2021)and is supported by the Graduate School ‘C 1-Chemistry for Resource andEnergy Management’ of the Landesexzellenzinitiative Hamburg (LEXI).MDP024Bacteria and archaea involved in anaerobic digestion ofdistillers grains with solublesS. Kleinsteuber* 1 , A. Ziganshin 1,2 , T. Schmidt 3 , H. Harms 11 Department ofEnvironmental Microbiology, Helmholtz Center forEnvironmental Research (UFZ), Leipzig, Germany2 Microbiology, Kazan Federal University, Kazan, Russian Federation3 German Biomass Research Center (DBFZ), Biochemical Conversion,Leipzig, GermanyCereal distillers grains with solubles (DDGS), a by-product from bioethanolindustry, were tested as a possible substrate for biogas production inmesophilic laboratory scale anaerobic digesters. The effects of variousorganic loading rates (OLR), iron additives for sulfide precipitation, as wellas aerobic substrate pretreatment on microbial community structure andperformance were investigated. Five continuously stirred tank reactors wererun under constant conditions and monitored for biogas production andcomposition along with other process parameters such as pH, volatile fattyacids (VFA) and ammonium. The microbial communities in the reactorswere investigated for their phylogenetic composition by terminal restrictionfragment length polymorphism (T-RFLP) analysis and sequencing of 16SrRNA genes. Iron additives for sulfide precipitation significantly improvedthe process stability and efficiency, whereas aerobic pretreatment of thegrains had no effect. The bacterial subcommunities were highly diverse, andtheir composition did not show any correlation with reactor performance.The dominant phylotypes were affiliated to the phylum Bacteroidetes,among them various members of the Porphyromonadaceae. Furthermore,members of the Actinomycetales seemed to play a significant role, whereasClostridia were less abundant. The archaeal subcommunities were lessdiverse and correlated with the reactor performance. The well-performingreactors operated at lower OLR and amended with iron chloride weredominated by aceticlastic methanogens of the genus Methanosaeta. Thewell-performing reactor operated at a high OLR and supplemented with ironhydroxide was dominated by Methanosarcina ssp. The reactor without ironadditives was characterized by lowest biogas yield, accompanied by VFAaccumulation and high hydrogen sulfide content, and was dominated byhydrogenotrophic methanogens of the genus Methanoculleus. Our resultsshow that distillers grains are a valuable feedstock for biogas production butthe use of iron additives is needed to ensure high biogas yield.MDP026Impact of fungal aldehyde dehydrogenase onectomycorrhizal symbiosisK. Krause, T. Asiimwe, C. Henke*, E. KotheInstitute of Microbiology, Microbial Phytopathology, Friedrich SchillerUniversity, Jena, GermanyEctomycorrhizal fungi are known to improve plant growth, the supply ofnutrients and protect plants from pathogens during symbiosis. We isolated afungal aldehyde dehydrogenase (ALDH) encoding gene ald1 from thebasidiomycete Tricholoma vaccinum. ALDHs catalyze the conversion ofaldehyde to carboxylic acid in alcohol metabolism.Ald1 shows specific expression in ectomycorrhiza during interaction withthe compatible host spruce (Picea abies). It has a function in thedetoxification of alcohols and aldehydes occurring in mycorrhizal biotopesand is involved in phytohormone production. By using competitive and realtimeRT-PCR, ald1 was shown to be induced in response to alcohol- andaldehyde-related stress. Overexpression of ald1 in T. vaccinum resulted in anincrease in ethanol stress tolerance of the fungus. Phylogenetic analyzesrevealed duplication events within the specific fungal ALDH family, whichwe verified with T. vaccinum ALDH sequences (ald1, ald2 and ald3).MPV001A metaproteomics approach to study host-pathogeninteractions between Pseudomonas aeruginosa andCaenorhabditis elegansJ. Toller* 1 , B. Roschitzki 2 , C. Fortes 2 , M. Givskov 3 , L. Eberl 1 , K. Riedel 41 Institute of Plant Biology, Department of Microbiology, University ofZurich, Zurich, Switzerland2 Functional Genomics Center Zurich, ETH/UZH, Zurich, Switzerland3 Department of International Health, Immunology and Microbiology,University of Copenhagen, Copenhagen, Denmark4 Institute of Microbiology, Department of Microbial Proteomics, Universityof Technology, Braunschweig, GermanyPseudomonas aeruginosa, a Gram-negative opportunistic pathogen, causeslife-threatening and chronic infections in immunocompromised patients orpeople suffering from cystic fibrosis and employs an N-acyl homoserinelactone -mediated quorum sensing (QS) system to coordinate e.g. theexpression of virulence factors in a cell-density dependent manner. Nonmammalianinfection models such as Caenorhabditis elegans are wellestablishedtools to obtain first insights into molecular mechanismsunderlying bacterial pathogenicity. State-of-the-art gel-free, semiquantitativeproteomics based on unique spectral counting allowsinvestigating the „infectiosome” defined as global changes in proteinexpression in both the host and the pathogen during the infectious-likeprocess (ILP).spektrum | Tagungsband 2011