Editor: Alfons Stams
New insight into stratification of anaerobic methanotrophs in cold seep sediments
Article first published online: 14 JUL 2011
FEMS Microbiology Ecology © 2011 Federation of Microbiological Societies. Published by Blackwell Publishing Ltd. No claim to original Norwegian works
FEMS Microbiology Ecology
Volume 78, Issue 2, pages 233–243, November 2011
How to Cite
Roalkvam, I., Jørgensen, S. L., Chen, Y., Stokke, R., Dahle, H., Hocking, W. P., Lanzén, A., Haflidason, H. and Steen, I. H. (2011), New insight into stratification of anaerobic methanotrophs in cold seep sediments. FEMS Microbiology Ecology, 78: 233–243. doi: 10.1111/j.1574-6941.2011.01153.x
- Issue published online: 14 OCT 2011
- Article first published online: 14 JUL 2011
- Accepted manuscript online: 15 JUN 2011 10:18AM EST
- Received 7 December 2010; revised 16 May 2011; accepted 2 June 2011., Final version published online 14 July 2011.
Methane seepages typically harbor communities of anaerobic methane oxidizers (ANME); however, knowledge about fine-scale vertical variation of ANME in response to geochemical gradients is limited. We investigated microbial communities in sediments below a white microbial mat in the G11 pockmark at Nyegga by 16S rRNA gene tag pyrosequencing and real-time quantitative PCR. A vertical stratification of dominating ANME communities was observed at 4 cmbsf (cm below seafloor) and below in the following order: ANME-2a/b, ANME-1 and ANME-2c. The ANME-1 community was most numerous and comprised single or chains of cells with typical rectangular morphology, accounting up to 89.2% of the retrieved 16S rRNA gene sequences. Detection rates for sulfate-reducing Deltaproteobacteria possibly involved in anaerobic oxidation of methane were low throughout the core. However, a correlation in the abundance of Candidate division JS-1 with ANME-2 was observed, indicating involvement in metabolisms occurring in ANME-2-dominated horizons. The white microbial mat and shallow sediments were dominated by organisms affiliated with Sulfurovum (Epsilonproteobacteria) and Methylococcales (Gammaproteobacteria), suggesting that aerobic oxidation of sulfur and methane is taking place. In intermediate horizons, typical microbial groups associated with methane seeps were recovered. The data are discussed with respect to co-occurring microbial assemblages and interspecies interactions.