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

designated to be 4 fold higher than the activity of soluble proteins. Theseactivities indicate the oxidation of H 2 in the enrichment culture, but thespecies expressing hydrogenases could not yet be identified.Amplified sequences indicating CO 2 fixation via the Calvin Cycle matchedthe respective gene of T. crunogena.Additionally, to confirm and amend these first results, future investigationsshall include the identification of the hydrogenase expressing species,determination of hydrogen consumption rates and purification of thehydrogenase.EMP053Will not be presented!EMP054Bacterial degradation of 1H-benzotriazoleB. Morasch*, V. Heesel, D. Ilieva, S. HaderleinCenter for Applied Geoscience, Eberhard Karls University, Tübingen,GermanyThe complexing agent 1H-benzotriazole (BT) is a widely-used corrosioninhibitor in cooling and heating fluids, dishwashing detergents, and aircraftde-icing fluids. Due to its apparent persistence against biodegradation, it isubiquitously present in the aquatic environment. This is even more alarmingsince the compound has toxic effects. So far, BT has been considered nonbiodegradableby bacteria under oxic and anoxic conditions.In this study, we investigated the presence of an intrinsic biodegradationpotential for BT in two environmentally relevant compartments: sewagesludge and deep aquifer sediments. An aerobic sewage-sludge-derivedmixed culture coupled BT degradation with bacterial growth. Duringbiodegradation of BT, N-methylaniline and further transformation productswith absorption maxima at 367 and 550 nm were formed. This is the firstreport on bacterial growth with BT at mesophilic temperatures andunderlines that sewage sludge is a habitat of microorganisms can potentiallydegrade BT. The anaerobic intrinsic biodegradation potential for BT wasstudied in deep aquifer sediments eventually contaminated by heat transferfluids leaking from borehole heat exchangers. Concentrations of BT and itsderivative methyl-benzotriazole stayed constant over a period of more than200 days indicating that no intrinsic biodegradation potential was detectableunder the various redox conditions investigated.EMP055Dynamic of microbial communities in anaerobic biogasreactorsK. Heeg* 1,2 , M. Sontag 1 , E. Nettmann 11 APECS Nachwuchsgruppe, Leibniz Institute for Agricultural TechnologyPotsdam-Bornim e.V., Potsdam, Germany2 Department of Environmental Technology, Chair EnvironmentalMicrobiology, Institute of Technology, Berlin, GermanyKnowledge about the composition and function of microbial communitiesresponsible for substrate degradation and formation of biogas in anaerobicdigestion reactors is still rather incomplete. In this study, the dynamic of themicrobial diversity from start-up to the development of a stable biogasformation process into anaerobic digesters was investigated. The anaerobicdigestion was performed into an up-flow leach-bed reactor combined with amethane reactor and recirculation of the liquid phase. Reactors werecontinuously fed with wheat straw and run at thermophilic (56°C) andmesophilic (36°C) conditions. Samples were taken from the liquid phase anddigestate. Additionally, at stable process conditions, carrier bodies from themethane reactor were sampled. Terminal-restriction-fragment polymorphism(T-RFLP) of restriction endonuclease digested PCR-amplified 16S rDNAwas applied to analyse changes into the community structures. Furthermore,16S rRNA gene libraries were constructed to get detailed insights into thecomposition of the microbial communities at the date of start-up phase andstable process of biogas formation. The results of this study provide a basisfor the modelling and optimisation of the overall anaerobic digestion processwithin the APECS project. The aim of APECS (Anaerobic Pathways torenewable Energies and Carbon Sinks) is to provide the scientific andtechnical basis for an efficient and sustainable production of bio-methane asa high quality fuel and biochar as a long lasting carbon sink and an efficientsoil improver.EMP056Comparative and functional genomics ofMethylobacterium and Hyphomicrobium strainsdegrading halogenated methanesE. Muller 1 , A. Lajus 2 , M. Farhan Ul Haque 1 , T. Nadalig 1 , C. Gruffaz 1 ,Y. Louhichi 1 , V. Barbe 2 , S. Mangenot 2 , C. Médigue 2 , F. Bringel 1 ,S. Vuilleumier* 21 University of Strasbourg, Strasbourg, France2 LABGeM, Genoscope-IG-CEA, Evry, FranceThe halogenated methanes dichloromethane and chloromethane are volatiletoxic halogenated solvents produced both naturally and industrially.Dichloromethane- and chloromethane-degrading bacteria have been modelsof choice to study microbial dehalogenation metabolism at thephysiological, biochemical and genetic levels. A comparative analysis ofcomplete genome sequences of halogenated methane degradingMethylobacterium and Hyphomicrobium strains (Vuilleumier et al., 2009;Muller et al., accepted), obtained at Genoscope and the US American JointGenomic Institute, was performed to complement the investigation ofdichloromethane- and chloromethane-degrading bacteria using functionalgenomics approaches (Muller et al., submitted; Roselli et al., submitted).Our study highlights both the importance of horizontal gene transfer in thedissemination of halomethane degradation genes in the environment, and theinvolvement of the Alphaproteobacterial core genome in specific adaptationsto dehalogenative metabolism.[1] Vuilleumier, S. et al (2009): Methylobacterium genome sequences: a reference blueprint toinvestigate microbial metabolism of C1 compounds from natural and industrial sources. PLoS ONE 4,e5584.[2] Muller, E. et al (accepted). Dichloromethane-degrading bacteria in the genomic age. Res.Microbiol.EMP057Metaproteomics to investigate the impact of sampling-sitebiogeochemistry on structure and functionality of leaflitterdegrading microbial communitiesT. Schneider 1 , K. Keiblinger 2 , M. Kucklick* 3 , E. Schmid 1 , L. Eberl 1 ,S. Zechmeister-Boltenstern 2 , K. Riedel 31 Institute of Plant Biology, University of Zürich, Zurich, Switzerland2 Federal Office and Research Center for Forests – BFW, Vienna, Austria3 Institute of Microbiology, University of Technology, Braunschweig,GermanyThe composition of organic matter in natural ecosystems is stronglyinfluenced by the microorganisms present. Conversely, bacteria and fungiare limited by the amount and type of organic matter available in a givenenvironment, most of which is ultimately derived from plants. Changes inthe stoichiometry and biochemical constituents of plant litter may thereforealter species composition and elicit changes in the activities of microbialcommunities and their component parts. The identification of the microbialproteins of a given habitat together with the analysis of their phylogeneticorigin and their spatial and temporal distribution are expected to providefundamentally new insights into the role of microbial diversity inbiogeochemical processes.To relate structure and functionality of microbial communities involved inleaf-litter decomposition we determined biogeochemistry, communitystructure (PFLA-analyses), enzymatic activities, and analysed the proteincomplement of different litter types, which were collected in winter andspring at various Austrian sampling sites, by a semi-quantitative proteomicsapproach (1-D-SDS-PAGE combined with LC-MS/MS). In samples withhigh manganese and phosphor content a significant increase of fungalproteins from February to May was observed, which was in good agreementwith the PFLA-analyses showing similar trends towards an increase of thefungal community. In contrast, the PFLA analysis revealed no temporalchanges in the community at Achenkirch and even a decrease in thefungal/bacterial ratio at Klausen-Leopoldsdorf, two sampling sites low in Pand Mn; similar trends are reflected in our spectral counts. In conclusion,semi-quantitative proteome- and PFLA-analyses suggest that fungal andbacterial abundance positively correlates with the total amount of P and Mnwithin the different litter types. Spectral counts of extracellular enzymesdemonstrated a significant increase of these enzymes in the May, which wasalso mirrored by measurements of total enzymatic activities. The findingthat almost all hydrolytic enzymes identified from litter were of fungalorigin suggests a prominent role of fungi during aerobic litterdecomposition.spektrum | Tagungsband 2011