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

DCP degraders, and (b) soils influenced by earthworms harbor highlydiverse and novel 2,4-DCP-utilizing microorganisms.EMP078Bacteria emissions from broiler shedsU. Jäckel 1 , A. Gärtner 2 , A. Gessner 2 , E. Martin* 11 Federal Institute for Occupational Safety and Health (BAuA), BiologicalAgents, Berlin, Germany2 State Office for Nature, Environment and Consumer Protection of NorthRhine-Westphalia, Emission Measurement, Essen, GermanyEmissions of microorganisms from live stock buildings and theirenvironmental impact are hardly characterized. In particular residents in thearea of poultry processing plants are increasingly interested in thischaracterization because of a potential negative health effect. Therefore weinvestigated the microbial load and the bacterial diversity in emissionsamples from broiler sheds by cultivation independent analysis. Distributedover 2.5 fattening periods emissions samples from a broiler shed werecollected by impingement into isotonic NaCl solution. Concentrations ofmicroorganisms in emission samples clearly increased during the fatteningperiod from 3.7 x 10 7 cells per m 3 at the beginning to 9.4 x 10 8 cells per m 3at the end (after ~ 40d). Depending on the ventilation rate an enormousnumber of > 10 10 microbial cells was emitted from one broiler shed persecond. Qualitative analyses of bacterial diversity in emission samples forthe first time via a generation of 16S rRNA-gene clone libraries revealedthat the most abundant sequences (60%) of all 257 investigated clones couldbe assigned to the genus Staphylococcus. Among them sequences which aremost closely related to S. cohnii subsp. cohnii, S. cohnii subsp. urealyticum,S. nepalensis, S. lentus and S. arlettae. With respect to risk assessment, thelargest percentage of the identified 16S rRNA gene sequences can beassigned to bacteria which are classified to biological agents of the riskgroup 1 (German technical rule TRBA 466). However, bacterial species ofthe risk group 2, like Staphylococcus saprophyticus, Aerococcus viridans,Enterococcus hirae, E. faecium and Escherichia spp. were detected, too. Alltogether 28 different and well described bacterial species within 11 differentgenera were detected. But the remaining 21% of the analysed sequenceswere next related to yet uncultured bacteria. Against the background ofincreasing numbers of poultry fattening plants, both from ecological andmedical point of view the environmental impact of these emissions shouldbe considered in further investigations.EMP079Distribution of deep-biosphere bacteria in sediments andthe water column of the Black SeaN. Straaten*, H. Wichmann, M. Sahlberg, H. Cypionka, B. EngelenInstitue for Chemistry and Biology of the Marine Environment (ICBM), Carlvon Ossietzky University, Oldenburg, GermanyThe marine subseafloor biosphere is one of the largest biotopes on Earth.The microbial community is composed of a broad range of so far unculturedphyla with unknown metabolic properties. However, several communitymembers have pelagic or even terrestrial relatives (Batzke et al. 2004). Thescientific question of this study is to understand the origin of deepsubseafloorbacteria. Therefore, two different hypotheses were tested: (i)Bacteria that are abundant in the water column enter their habitat bysedimentation and survive long-term burial. (ii) The extreme environmentalconditions select for specific phylotypes that thrive in the deep-subseafloorbiosphere.In this study, samples were collected from the Black Sea (Meteor cruiseM72/5) which was chosen as a model habitat as it is characterized by astratified water column. To span the whole range of redox regimes, sampleswere taken from oxic surface waters, the oxic-anoxic transition zone, anoxicbottom waters and sediments down to a depth of 8 meters below seafloor(mbsf). The goal was to focus on four model organisms and not to analysethe whole microbial community composition. Those were members of theRoseobacter clade, the Chloroflexi, Photobacterium sp. and Rhizobiumradiobacter. While Roseobacter affiliated bacteria and Photobacterium sp.are abundant in the water column but are also found in surface sediments(Sass et al. 2010, Süß et al. 2008), the Chloroflexi and R. radiobacterrepresent highly abundant members of the deep-subseafloor biosphere (Süßet al. 2006, Wilms et al. 2006). Analyses were performed by usingquantitative PCR (qPCR) on original samples and enrichment cultures incombination with molecularly steered cultivation.Based on the results of the qPCR, we were able to quantify the naturalabundance of the four model organisms in the different habitats and couldshow a successful enrichment in our culture media. The molecular screeningof serial dilution cultures by specific PCR was used to identify and isolateunique phylotypes. Isolates belonging to the four model organisms weresubjected to further physiological characterisation.EMP080Diversity and abundance of Roseobacter-affiliatedbacteria on various algal surfaces and in sedimentsJ. Lucas* 1 , T. Schütte 1 , A. Hecht 2 , O. Frank 3 , H. Wang 4 , D. Patzelt 4 ,S. Haas 2 , N. Gödecke 2 ,D.Kaufholdt 2 , U. Lau 2 , I. Wagner-Döbler 4 ,H. Cypionka 1 , B. Engelen 11 Institue for Chemistry and Biology of the Marine Environment (ICBM),Carl von Ossietzky University, Oldenburg, Germany2 Institute of Microbiology, University of Technology, Braunschweig,Germany3 German Collection for Microorganisms and Cell Cultures, Braunschweig,Germany4 Helmholtz Center for Infection Research, Braunschweig, GermanyRoseobacter-affiliated bacteria belong to the most abundant marinemicroorganisms. They inhabit a wide range of ecological niches, especiallyin coastal environments and the polar oceans. Members have been found tobe free-living, particle-associated, in relationships with marinephytoplankton, invertebrates and vertebrates. This widespread distribution isreflected in a broad physiological spectrum. Most of the Roseobacteraffiliatedbacteria are known to be aerobic heterotrophs, some are facultativeanaerobes and others are even capable of performing aerobic anoxgenicphotosynthesis (AAP). The ecology, physiology and molecular biology ofthe Roseobacter clade is now investigated in a transregional collaborativeresearch center (SFB/TRR51).Sediments have been identified as the third-most important habitat for theRoseobacter-clade [1]. It has been shown that this group contributes with anaverage of 3% to the microbial communities thriving in marine surfacesediments, but they were also detected in deep anoxic layers. However, theabundance, distribution and metabolic potential of sediment-dwellingRoseobacter have not been studied systematically so far.To elucidate their role in marine sediments in comparison to other surfaces,we have analyzed algal and sediment samples from Helgoland on differentphylogenetic levels. DGGE was performed using primers specific forBacteria, Rhodobacteraceae and Phaeobacter. The fraction of AAP bacteriawas traced by specifically targeting the pufML gene, which encodes for twohighly conserved structural proteins of the light harvesting complex. Allphylogenetic and physiological groups were analyzed by quantitative PCR.To confirm the results, numbers of bacteria and Rhodobacteraceae weredetermined by CARD-FISH. Additionally, a cultivation approach wasconducted to obtain isolates for further physiological studies.An unexpected high number of Rhodobacteraceae was found within thesediment samples. Diversity analysis via group specific PCR revealed ahigher diversity on algae surfaces than in the sediments with representativesspreading over the whole Rhodobacteraceae lineage.[1] Buchan, A. et al (2005): Overview of the marine Roseobacter lineage. Appl Environ Microbiol 71:5665-5677.EMP081Reconstituting lantipeptide biosynthesis in E. coliH. Kage*, M. NettLeibniz Institute for Natural Product Research and Infection Biology Hans-Knöll-Institute, Junior Research Group Secondary Metabolism of PredatoryBacteria, Jena, GermanyLantipeptides are ribosomally synthesized and posttranslationally modifiedpeptides containing lanthionine or methyl-lanthionine rings. They are mainlyproduced by Gram-positive bacteria and exhibit significant biologicalactivities targeting components of the bacterial plasma membrane, e.g. lipidII. Since their bactericidal effect often stems from more than onemechanism, the emergence of resistance to lantipeptides is rarely observed.Therefore, lantipeptides represent promising leads for drug development.Recent genome mining studies unveiled that the genes responsible forlantipeptide biosynthesis are widespread in the eubacterial kingdom [1; 2].The Gram-negative filamentous bacterium, Herpetosiphon aurantiacusATCC 23779, harbours two putative lantipeptide gene clusters in its genomespektrum | Tagungsband 2011