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DNA Stable-Isotope Probing DNA-SIP
Published on: August 2, 2010
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Linking Uncultivated Microbial Populations and Benthic Carbon Turnover by Using Quantitative Stable Isotope Probing
Ömer K Coskun1, Monica Pichler1, Sergio Vargas1
1Department of Earth and Environmental Sciences, Ludwig-Maximilians Universität München, Munich, Germany.
Applied and Environmental Microbiology
|July 8, 2018
Summary
This study reveals the crucial roles of uncultivated microbes in benthic carbon cycling. Quantitative DNA stable isotope probing (qSIP) identified specific bacterial and archaeal groups actively involved in organic matter turnover in lake sediments.
Area of Science:
- Microbial Ecology
- Biogeochemistry
- Environmental Microbiology
Background:
- Benthic microbial communities are diverse and control carbon fluxes.
- The function of uncultivated microbial groups in organic matter turnover remains unclear.
- Understanding these microbes is key to comprehending benthic carbon cycling.
Purpose of the Study:
- To link uncultivated bacterial and archaeal populations to carbon turnover in lacustrine sediments.
- To quantify the contribution of specific microbial groups to autotrophy and heterotrophy.
- To elucidate the role of these microbes in benthic carbon cycling.
Main Methods:
- Quantitative DNA stable isotope probing (qSIP) using [13C]bicarbonate.
- Incubation of lacustrine surface sediments under dark conditions.
- Extraction and concentration of high-molecular-weight (HMW) organic matter for labeling.
Main Results:
- Ammonia-oxidizing archaea (AOA) were identified as dominant active chemolithoautotrophs.
- 823 microbial operational taxonomic units (OTUs) were involved in turning over labeled organic matter.
- Uncultivated taxa, including Latescibacteria and Bathyarchaeota, contributed significantly to biomass turnover.
Conclusions:
- This study provides quantitative evidence for the active metabolism of poorly understood microbial groups in benthic carbon turnover.
- Archaeal ammonia oxidizers drive 'dark' primary production, supporting heterotrophic bacteria.
- Findings expand knowledge of microbial populations in benthic food webs and the significance of uncultivated microbes.
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