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Microbial community structure and functioning in marine sediments associated with diffuse hydrothermal venting
Tim Urich1, Anders Lanzén, Runar Stokke
1Division of Archaea Biology and Ecogenomics, Department of Ecogenomics and Systems Biology, University of Vienna, 1090, Vienna, Austria; Centre for Geobiology, University of Bergen, 5007, Bergen, Norway.
Environmental Microbiology
|October 12, 2013
Summary
Microbial communities in diffuse deep-sea hydrothermal vents are dominated by specific bacteria and archaea. These organisms utilize sulphur and methane oxidation, and carbon fixation, highlighting their crucial role in these unique ecosystems.
Area of Science:
- Marine Biology
- Microbial Ecology
- Geochemistry
Background:
- Deep-sea hydrothermal vents host chemosynthetic ecosystems, with microbial life forming the base of food webs.
- While high-temperature vents are well-studied, the microbial communities in low-temperature diffuse vents remain poorly understood.
Purpose of the Study:
- To investigate the structure and function of microbial communities in diffuse venting sediments.
- To understand the metabolic activities and ecological roles of microbes in these environments.
Main Methods:
- Integrated 'omics' approach: metatranscriptomics, metaproteomics, and metagenomics.
- Polymerase chain reaction-independent three-domain community profiling.
- Analysis of gene expression and protein activity related to metabolic pathways.
Main Results:
- Highly similar microbial communities found in two diffuse venting sediments, dominated by Epsilon-, Delta-, and Gammaproteobacteria, ciliates, nematodes, and archaea.
- High expression of sulphur and methane oxidation, carbon fixation, and respiratory pathways (aerobic and anaerobic).
- Upregulated chemotaxis and flagella genes indicate adaptation to dynamic, gradient-rich environments.
Conclusions:
- Distinct taxonomic groups were linked to major metabolic pathways, providing insights into their functional roles.
- This research enhances understanding of microbial community functioning in diffuse hydrothermal vent sediments.
- The findings shed light on the ecological strategies of microorganisms in deep-sea chemosynthetic ecosystems.
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