CAENEUS · Crenarchaeota ecology and nutrient utilization in the subsurface ocean (CAENEUS)
FP7 — People (Marie Curie Actions)
- Duration
- 2010-06-01 → 2012-05-31
- EU contribution
- €163,623
- Participants
- 1
- Scheme
- MC-IEF
Lines connect the coordinator with its partners.
Results in brief
Crenarchaeota ecology and nutrient utilization in the subsurface ocean
Project objectives CAENEUS aims to study microbial communities in the dark open ocean by determining their abundance, identity, activity and the environmental factors influencing their distribution and activity. Project results To address these objectives I joined two cruises. In October 2010, on RV Pelagia in the open Atlantic, I took samples for molecular analysis, single-cells analysis, prokaryotic activities and abundance. The samples have already been processed and a manuscript has been submitted for publication. In March 2011, on RRS James Cook, we focused on a transect from 52 oS to the equator in the Southern Atlantic Ocean and samples were taken for molecular analysis, single-cells analysis, prokaryotic activities and abundance. The analyses of these samples is still in progress. Apart from the research activities, I have participated in all the seminars, journal clubs and management meetings of the Department of Marine Biology at the University of Vienna. The results of this project have been presented at three international meetings: SAME12, Ocean Science Meeting and ISME14. One manuscript is submitted for publication, and one is currently being prepared and will be submitted in October 2012. Project impact The project took advantage of recent major scientific findings and will substantially increase our knowledge on the ecology of marine prokaryotes thriving throughout the world's oceans. In general, the deep sea has received considerable scientific attention in recent years, since it has been recognised that we know more about the surface of the moon than about the deep pelagic waters comprising the largest marine subsystem amounting to about 80 % of global ocean volume. Using molecular tools, several novel metabolic pathways have recently been discovered in the deep sea. The work in this project has allowed us to effectively link genomics with biogeochemical rate measurements. This has substantially widened my scientific horizon, and allowed me to acquire technological know-how and to stimulate and advance my scientific career.
Data: CORDIS, © European Union
Project objective
Over the past 10 years, it become apparent that Crenarchaeota are not only striving in some extreme environments but that they are ubiquitously present in the aquatic and terrestrial environment including the oceanic water column. In the pelagic realm of the ocean, their relative contribution to the total prokaryotic abundance increases with depth. It has been shown that the mesophilic Marine Crenarchaeota Group I (MCGI) live chemoautotrophically, fixing carbon dioxide as carbon source and using ammonia as an energy source. Based on the abundance of the amoA gene, encoding the ammonia monoxygenase, a key enzyme common to all nitrifiers, it has been deduced that they might be more important nitrifiers than Bacteria. This has never been tested thus far, however. In this proposal, we will investigate the enigma of this MCGI cluster is utilizing ammonia in the deep ocean, where ammonia concentrations are below the detection limit using conventional analytical methods. We will determine the distribution of archaeal and bacterial amoA gene abundance throughout the water column down to abyssopelagic realms in the northern North Atlantic and the tropical Atlantic and distinguish between archaeal and bacterial nitrification and dark CO2 fixation rates. Using three different single-cell approaches in a correlative way, we will specifically focus on the potential shifts in the phylogenetic composition of the MCGI cluster and its autotrophic activity with depth, as ammonia concentrations are probably below the nanomolar level in bathypelagic waters. Taken together, we will determine for the first time, the relative importance of archaeal vs. bacterial nitrification in the ocean. By focusing on two Atlantic sites with contrasting age of deep-water masses and accompanied to that, contrasting deep-water ammonia concentrations, we will be able to investigate the entire range of diversity and metabolic adaptation in Marine Crenarchaeota Group I.
Original text from CORDIS.
Participants
- UNIVERSITAT WIEN · WienCoordinatorAustria
Links
Data: CORDIS, © European Union