ERC FUNDED PROJECTS

For over a century it was believed that ammonium could only be oxidized by microbes in the presence of oxygen. The possibility of anaerobic ammonium oxidation (anammox) was considered impossible. However, about 10 years ago the microbes responsible for the anammox reaction were discovered in a wastewater plant. This was followed by the identification of the responsible bacteria. Recently, the widespread environmental occurrence of the anammox bacteria was demonstrated leading to the realization that anammox bacteria may play a major role in biological nitrogen cycling. The anammox bacteria are unique microbes with many unusual properties. These include the biological turn-over of hydrazine, a well known rocket fuel, the biological synthesis of ladderane lipids, and the presence of a prokaryotic organelle in the cytoplasma of anammox bacteria. The aim of this project is to obtain a fundamental understanding of the metabolism and ecological importance of the anammox bacteria. Such understanding contributes directly to our environment and economy because the anammox bacteria form a new opportunity for nitrogen removal from wastewater, cheaper, with lower carbon dioxide emissions than existing technology. Scientifically the results will contribute to the understanding how hydrazine and dinitrogen gas are made by the anammox bacteria. The research will show which gene products are responsible for the anammox reaction, and how their expression is regulated. Furthermore, the experiments proposed will show if the prokaryotic organelle in anammox bacteria is involved in energy generation. Together the environmental and metabolic data will help to understand why anammox bacteria are so successful in the biogeochemical nitrogen cycle and thus shape our planets atmosphere. The different research lines will employ state of the art microbial and molecular methods to unravel the exceptional properties of these highly unusual and important anammox bacteria.

2 500 000 €

Start date: 2009-01-01, End date: 2013-12-31

One of the central goals in evolutionary biology is to understand adaptation. Experimental evolution represents a highly promising approach to study adaptation. In this proposal, a freshly collected D. simulans population will be allowed to adapt to laboratory conditions under two different temperature regimes: hot (27°C) and cold (18°C). The trajectories of adaptation to these novel environments will be monitored on three levels: 1) genomic, 2) transcriptomic, 3) phenotypic. Allele frequency changes during the experiment will be measured by next generation sequencing of DNA pools (Pool-Seq) to identify targets of selection. RNA-Seq will be used to trace adaptation on the transcriptomic level during three developmental stages. Eight different phenotypes will be scored to measure the phenotypic consequences of adaptation. Combining the adaptive trajectories on these three levels will provide a picture of adaptation for a multicellular, outcrossing organism that is far more detailed than any previous results. Furthermore, the proposal addresses the question of how adaptation on these three levels is reversible if the environment reverts to ancestral conditions. The third aspect of adaptation covered in the proposal is the question of repeatability of adaptation. Again, this question will be addressed on the three levels: genomic, transcriptomic and phenotypic. Using replicates with different degrees of genetic similarity, as well as closely related species, we will test how similar the adaptive response is. This large-scale study will provide new insights into the importance of standing variation for the adaptation to novel environments. Hence, apart from providing significant evolutionary insights on the trajectories of adaptation, the results we will obtain will have important implications for conservation genetics and commercial breeding.

2 452 084 €

Start date: 2012-07-01, End date: 2018-06-30

The discovery of deep-sea hydrothermal vents in 1977 was one of the most profound findings of the 20th century, revolutionizing our perception of energy sources fueling primary productivity on Earth. These ecosystems are based on chemosynthesis, that is the fixation of carbon dioxide into organic compounds as in photosynthesis, but using inorganic compounds such as sulfide, methane or hydrogen, as energy sources instead of sunlight. Hydrothermal vents support tremendous biomass and productivity of which the majority is generated through symbiotic microbe-animal associations. Bathymodiolus mussels are able to build extraordinarily large and productive communities at hydrothermal vents because they harbor symbiotic bacteria that use inorganic energy sources from the vent fluids to feed their hosts via carbon fixation. In addition to their beneficial symbionts, the mussels are infected by a novel bacterial parasite that exclusively invades and multiplies in their nuclei. In the work proposed here, I will use a wide array of tools that range from deep-sea in situ instruments to sophisticated molecular, 'omic' and imaging analyses to study the microbiome associated with Bathymodiolus mussels. The proposed research bridges biogeochemistry, ecological and evolutionary biology, and molecular microbiology to develop a systematic understanding of the symbiotic interactions between microbes, their hosts, and their environment in one of the most extreme and fascinating habitats on Earth, hydrothermal vents.

2 499 122 €

Start date: 2014-02-01, End date: 2019-01-31

This project addresses a key issue in fundamental research - one that has challenged ecologists ever since Darwin s time that is why some species are common, and others rare, and why, despite marked turnover at the level of individual species abundances, the structure of a community is generally conserved through time. Its aim is to examine the temporal dynamics of species abundance distributions (SADs), and to assess the capacity of these distributions to withstand change (resistance) and to recover from change (resilience). These are topical and important questions given the increasing impact that humans are having on the natural world. There are three components to the research. First, we will model SADs and predict responses to a range of events including climate change and the arrival of invasive species. A range of modeling approaches (including neutral, niche and statistical) will be adopted; by incorporating temporal turnover in hitherto static models we will advance the field. Second, we will test predictions concerning the resistance and resilience of SADs by a comparative analysis of existing data sets (that encompass communities in terrestrial, freshwater and marine environments for ecosystems extending from the poles to the tropics) and through a new field experiment that quantifies temporal turnover across a community (unicellular organisms to vertebrates) in relation to factors both natural (dispersal limitation) and anthropogenic (human disturbance) thought to shape SADs. In the final part of the project we will apply these new insights into the temporal dynamics of SADs to two important conservation challenges. These are 1) the conservation of biodiversity in a heavily utilized European landscape (Fife, Scotland) and 2) the conservation of biodiversity in Mamirauá and Amaña reserves in Amazonian flooded forest. Taken together this research will not only shed new light on the structure of ecological communities but will also aid conservation.

1 812 782 €

Start date: 2010-08-01, End date: 2016-01-31