Prof. Marcus A. Horn

Marcus A. Horn
Member in P2: Regulation, ecophysiology, and kinetic parameters of uncultured N-gas flux associated anaerobic microbial communities in agricultural soils |


Curriculum vitae


2011:    Habilitation in Microbiology, University of Bayreuth; Title: ‘Microbial Metabolism of Atmospheric Trace Gases in Terrestrial Ecosystems: Implications for Global Warming’’

2004:    Dissertation (summa cum laude), University of Bayreuth; Title: ‘Mikrobiologie der N2O-Bildung im Darm von Regenwürmern (Oligochaeta, Lumbricidae)’

1993-2000: Study of Biology and Chemistry, Universities of Bayreuth and York (UK), Diploma in Biology, Intermediate Exam in Chemistry



Since 2016: Professor of Soil Microbiology (W2), University of Hannover

2011-2016:    Associate Professor (A13/14 permanent), Department of Ecological Microbiology, University of Bayreuth

2006: Visiting scientist at the Department of Microbial Ecology, University of Vienna, Austria

2004-2011: Assistant Professor (C1/A13), Department of Ecological Microbiology, University of Bayreuth

2000-2004: Doctoral position, Department of Ecological Microbiology, University of Bayreuth


Recent Important Publications 

Schmidt, O., Hink, L., Horn, M.A., and H.L. Drake. 2016. Peat: home to novel syntrophic species that feed acetate- and hydrogen-scavenging methanogens. ISME Journal: doi: 10.1038/ismej.2015.256.

Borken, W., Horn, M.A., and K.-H. Knorr. 2015. Significant non-symbiotic nitrogen fixation in Patagonian ombrotrophic bogs. Global Change Biology: 21: 2357-2365.

Palmer, K., and M.A. Horn 2015. Denitrification activity of a remarkably diverse fen denitrifier community in Finnish Lapland is nitrate limited. PLOSone 10: e0123123. 

Schmidt, O., Horn, M.A., Kolb, S., and H.L. Drake. 2015. Temperature impacts differentially on prokaryotes involved in the intermediary ecosystem metabolism in cellulose-supplemented methane-emitting peatland soil. Environmental Microbiology 17: 720-734.

Dallinger, A., and M.A. Horn. 2014. Agricultural soil and drilosphere as reservoirs of new and unusual assimilators of 2,4-dichlorophenol carbon. Environmental Microbiology 16: 84-100 (Special Issue: Metabolism & Biodegradation).

Liu, Y.-J., Liu, S.-J., Drake, H.L., and M.A. Horn. 2013. Consumers of 4-chloro-2-methylphenoxyacetic acid from agricultural soil and drilosphere harbour cadA, r/spdA, and tfdA-like gene encoded oxygenases. FEMS Microbiology Ecology 86: 114-129 (Special Issue: Microbial ecology of biogeochemical interfaces – diversity, structure and function of microhabitats in soil).

Kolb, S., and M.A. Horn. 2012. Microbial CH4 and N2O consumption in acidic wetlands. Frontiers in Terrestrial Microbiology 3: 78 (doi: 10.3389/fmicb.2012.00078).

Palmer, K., Biasi, C., and M.A. Horn. 2012. Contrasting denitrifier communities relate to contrasting N2O emission patterns from acidic peat soils in arctic tundra. ISME Journal 6: 1058-1077.

Liu, Y.J., A. Zaprasis, S.-J. Liu, H.L. Drake, and M.A. Horn. 2011. The earthworm Aporrectodea caliginosa stimulates abundance and activity of phenoxyalkanoic acid herbicide degraders. ISME Journal 5: 473-485.

Drake, H.L., and M.A. Horn.  2007.  As the worm turns:  the earthworm gut as a transient habitat for soil microbial biomes. Annual Reviews in Microbiology 61: 169–189.


Participant in DFG Research Programs 

Soil Processes (Research Group 562): 2005-2011 (PI) 

Biodiversity Exploratories (Priority Programme 1374): 2007-2011 (Co-PI) 

Biogeochemical Interfaces in Soil (Priority Programme 1315): 2007-2013 (PI) 

Denitrification in Agricultural Soils: Integrated Control and Modelling at Various Scales DASIM (Research Group 2337): 2016 – ongoing (PI)


Scientific Activities (last 5 years) 

Coordinative Tasks

2014-2016        Scientific Coordinator BayCEER Colloquium, University of Bayreuth

Associate Guest Editor 

2013-2016    Frontiers in Microbiology 

Editorial Board Member 

Since 2013    FEMS Microbiology Ecology

Since 2012    Applied and Environmental Microbiology


Scientific Meetings 

Organizing Commitee of session on microbial ecology (International Conference on Permafrost 2016, Potsdam)

Organizing Commitee of session “Microorganisms' impact on trace gas fluxes of terrestrial and aquatic ecosystems”  (VAAM Meeting 2014, Osnabrück).

Organizing Committee of International Symposium on “Biogeochemical Interfaces in Soil: Towards a Comprehensive and Mechanistic Understanding of Soil Functions”, 2014 in Leipzig

Organizing Committee of International Symposium on “Life in Microhabitats of Soils – Microbial Ecology of Biogeochemical Interfaces” (1.3. - 2.3.2012, Dornburg, Germany) 

Moderator of the subgroup 6 of PP1315 (2008 - 2011) “Architect and Actor – elucidate transformations of organic chemicals” of the Priority Program 1315 

Organization of joint meeting of Subgroup 6 and 4 (05.03. - 06.03.2012, Bayreuth UBT) of the Priority Program 1315 


Invited Talks

2016    Denitrifiers – manipulators of global warming. Institutskolloquium am 26.01.206, Institut für Landschaftsbiogeochemie, Leibniz-Zentrum für Agrarlandschaftsforschung (ZALF) e. V.

2015    Anaerobic food chain as driver of biohydrogen and methane production from complex organic matter. Kolloquium 25.11.2015, Landesamt für Landwirtschaft, Fresising

2014    Extreme nitrous oxide fluxes of permafrost soils: Do new denitrifier communities make the difference? International Society for Microbial Ecology (ISME) 15, 26.08.2014, Seoul, South Korea. 

2014    Denitrifying microbes as corner stones of nitrous oxide fluxes in peatlands. Seminar MPI for Chemistry, Mainz, 08.05.2014.

2013    Denitrifiers in permafrost affected soils as drivers of extreme and contrasting nitrous oxide fluxes.  BioGeo-Kolloquium, Universität Jena, 15.10.2013.

2013    Phenoxyacetic acid herbicide degradation in soil and drilosphere: What are microbial key players? Bodenkundliches Kolloquium, Universität Hohenheim, 29.04.2013.

2011    Unraveling earthworm-microbe interactions in soil (Keynote), 05.-07.10.11, GfÖ Workshop “Microbial-faunal interactions shaping soil processes”, Humboldt Universität Berlin.


Invited Reviewer      

Academy of Sciences of the Czech Republic, European Journal of Soil Science, Deutsche Forschungsgemeinschaft , FEMS Microbiology Ecology, Deutscher Akademischer Austauschdienst, FEMS Letters, European Research Council , Frontiers in Terrestrial Microbiology, German Israeli Foundation, Geoderma, Netherlands Organization for Scientific Research, International Journal of Systematic and Evolutionary Microbiology, Tiroler Wissenschaftsfonds, Applied and Environmental Microbiology, ISME Journal, Applied and Environmental Soil Science, Journal of Protistology, Applied Microbiology and Biotechnology, Letters in Applied Microbiology, Biogeochemistry, Microbial Ecology, Biogeosciences, Molecular Ecology, Biology and Fertility of Soils, Plant and Soil, Ecological Engineering , PLOSone, Ecology, Pedobiologia, Environmental Microbiology, Pedosphere, Environmental Pollution, Soil Biology and Biochemistry, Environmental Science & Technology, Systematic and Applied Microbiology, European Journal of Soil Biology, Zoology



Vereinigung für Allgemeine und Angewandte Mikrobiologie VAAM), American Society for Microbiology (ASM), International Society for Microbial Ecology (ISME)

Scientific interest

  • Community to gene scale regulation of nitrogen dissimilating microbes: Relevance for nitrate removal and greenhouse gas production in wetlands, temperate and permafrost affected soils.
  • Symbiotic nitrogen fixation associated with wetland plants: Diazotrophs as key microbes
  • Earthworm-microbe interactions in soils and their relevance to soil processes: Greenhous gas metabolism and pollutant degradation.
  • Regulation of the anaerobic feed chain in natural and engineered ecosystems: From biopolymers to methane.
  • Microbial (Micro-)pollutant transformations in soils and sediments: Potential for bioremediation.