Enrichment of a microbial community performing anaerobic oxidation of methane in a continuous high-pressure bioreactor
1 State Key Laboratory of Microbial Metabolism and School of Life Science & Biotechnology, State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Dongchuan Rd. 800, Shanghai, 200240, P. R. China
2 Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, Gent, 9000, Belgium
BMC Microbiology 2011, 11:137 doi:10.1186/1471-2180-11-137Published: 16 June 2011
Anaerobic oxidation of methane coupled to sulphate reduction (SR-AOM) prevents more than 90% of the oceanic methane emission to the atmosphere. In a previous study, we demonstrated that the high methane pressure (1, 4.5, and 8 MPa) stimulated in vitro SR-AOM activity. However, the information on the effect of high-pressure on the microbial community structure and architecture was still lacking.
In this study we analysed the long-term enrichment (286 days) of this microbial community, which was mediating SR-AOM in a continuous high-pressure bioreactor. 99.7% of the total biovolume represented cells in the form of small aggregates (diameter less then 15 μm). An increase of the total biovolume was observed (2.5 times). After 286 days, the ANME-2 (anaerobic methanotrophic archaea subgroup 2) and SRB (sulphate reducing bacteria) increased with a factor 12.5 and 8.4, respectively.
This paper reports a net biomass growth of communities involved in SR-AOM, incubated at high-pressure.