HYADES · Hydrostatic pressure and prokaryotic activity in the deep sea
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2016-04-15 → 2018-04-14
- EU contribution
- €178,157
- Participants
- 1
- Scheme
- MSCA-IF-EF-ST
Lines connect the coordinator with its partners.
Results in brief
Hydrostatic pressure and prokaryotic activity in the deep sea
The deep-sea realm (depth > 200 m) is characterized by low temperature (0–4°C), absence of sunlight, and high hydrostatic pressure, which increases by 1 atm every 10 m depth. It is a key site for degrading organic matter back to carbon dioxide and into other inorganic compounds. This is a crucial process for driving the carbon cycle in the deep-sea mediated largely by microbes, especially prokaryotes. Recently, global carbon budget estimates indicated an unresolved mismatch between organic carbon supply and prokaryotic carbon demand in the deep-sea. Hence measured prokaryotic activity in the deep-sea exceeds the input of sedimenting organic carbon from the sunlit euphotic layer. Without realistic measurements on prokaryotic activity, we cannot advance our understanding on the ocean carbon cycle. Thus, one of the most important issues discussed for some decades remains still unresolved as is the role of hydrostatic pressure on deep-sea prokaryotic activity. Because prokaryotic activity is traditionally measured on board of research vessels under atmospheric pressure conditions, the results obtained hitherto on deep sea heterotrophic microbial activity might be biased if hydrostatic pressure does influence heterotrophic microbial activity. While it has been shown already in the 1940s, that there are some piezophilic (‘pressure-loving’) bacteria present in the deep-sea preferentially growing under high-pressure conditions, their ecological role is still not clear. Overall, the main objectives of HYADES project are to understand deep-sea prokaryotic activity and metabolism under in situ hydrostatic pressure and reveal the contribution of piezophilic prokaryotes to the total prokaryotic community in the dark ocean.
Data: CORDIS, © European Union
Project objective
The main goal of this project is to understand deep-sea prokaryotic activity and metabolism under in situ hydrostatic pressure and reveal the contribution of piezophilic prokaryotes to the total prokaryotic community in the dark ocean. In the project, deep-sea prokaryotes will be incubated under in situ hydrostatic pressure with an in situ microbial incubator (ISMI) which has been developed in the lab of the applicant’s PhD supervisor in Japan. The ISMI, as the name suggests, is an instrument to incubate deep-sea biota at the depth of sampling and hence, without change of the hydrostatic pressure and temperature. Deep-sea prokaryotes will also be incubated under atmospheric pressure at otherwise identical conditions as a control, thus, this approach will reveal the impact of hydrostatic pressure on prokaryotic activity. Consequently, we will obtain information on the phylogeny and metabolism of piezophilic and piezotolerant prokaryotic populations in the dark ocean. The ISMI will be deployed during two long (ca. 1 month) research cruises, and a short (a week) cruise in the project. Prokaryotic heterotrophic and autotrophic production under in situ hydrostatic pressure will be measured, and piezophilic, piezotolerant, and piezosensitive prokaryotes will be studied with microautoradiography combined with catalyzed reporter deposition fluorescence in situ hybridization (MICRO-CARD-FISH) and omics approaches. Measuring metabolic activity of deep-sea microbes under in situ pressure conditions represents a major endeavor, and it remains unknown how large the fraction of piezophilic and piezotolerant prokaryotes in the deep ocean really is. The project has the potential to provide an answer to the question of the metabolic activity of microbes under in situ pressure conditions in the global ocean.
Original text from CORDIS.
Participants
- UNIVERSITAT WIEN · WienCoordinatorAustria
Links
Data: CORDIS, © European Union