Editor: Alfons Stams
Prokaryotic functional diversity in different biogeochemical depth zones in tidal sediments of the Severn Estuary, UK, revealed by stable-isotope probing
Article first published online: 15 FEB 2010
© 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved
FEMS Microbiology Ecology
Volume 72, Issue 2, pages 179–197, May 2010
How to Cite
Webster, G., Rinna, J., Roussel, E. G., Fry, J. C., Weightman, A. J. and Parkes, R. J. (2010), Prokaryotic functional diversity in different biogeochemical depth zones in tidal sediments of the Severn Estuary, UK, revealed by stable-isotope probing. FEMS Microbiology Ecology, 72: 179–197. doi: 10.1111/j.1574-6941.2010.00848.x
- Issue published online: 12 APR 2010
- Article first published online: 15 FEB 2010
- Received 16 July 2009; revised 13 November 2009; accepted 26 January 2010.Final version published online 16 March 2010.
- stable-isotope probing;
- marine sediments;
Stable isotope probing of prokaryotic DNA was used to determine active prokaryotes using 13C-labelled substrates (glucose, acetate, CO2) in sediment slurries from different biogeochemical zones of the Severn Estuary, UK. Multiple, low concentrations (5 × 100 μM) of 13C-substrate additions and short-term incubations (7 days) were used to minimize changes in the prokaryotic community, while achieving significant 13C-incorporation. Analysis demonstrated clear metabolic activity within all slurries, although neither the net sulphate removal nor CH4 production occurred in the anaerobic sulphate reduction and methanogenesis zone slurries. Some similarities occurred in the prokaryotic populations that developed in different sediment slurries, particularly in the aerobic and dysaerobic zone slurries with 13C-glucose, which were dominated by Gammaproteobacteria and Marine Group 1 Archaea, whereas both anaerobic sediment slurries incubated with 13C-acetate showed incorporation into Epsilonproteobacteria and other bacteria, with the sulphate reduction zone slurry also showing 13C-acetate utilization by Miscellaneous Crenarchaeotic Group Archaea. The lower potential energy methanogenesis zone slurries were the only conditions where no 13C-incorporation into Archaea occurred, despite Bacteria being labelled; this was surprising because Archaea have been suggested to be adapted to low-energy conditions. Overall, our results highlight that uncultured prokaryotes play important ecological roles in tidal sediments of the Severn Estuary, providing new metabolic information for novel groups of Archaea and suggesting broader metabolisms for largely uncultivated Bacteria.