|Caractérisation des capacités de dégradation de communautés bactériennes de sédiments marins : adaptation, processus métaboliques et influence des régimes d’oxygénation|
|In DEpth characterization of HC-degradation CAPAcities of marine sediment microbial communities: adaptation, metabolic processes and influence of oxyGEnation regimes|
Recently, we showed that the effect of petroleum on bacterial communities is enhanced by the presence of burrowing organisms (Stauffert et al, 2010 ; DHYVA project). The reworking activity is augmented, integrase gene expression increased and the bacterial communities are more deeply changed resulting in a different community than that observed without burrowing organisms. Nevertheless both communities have overall similar degradation efficiencies highlighting the functional redundancy involved in hydrocarbons degradation. These results rise up several important questions to understand the mechanisms underpinning the bacterial communities structuring:
- How petroleum and the adaptative mechanisms induced influence the communities’ structures?
- How the fluctuation of environmental parameters, particularly oxygenation and redox oscillations resulting from the biological (bioturbation) or mechanical (harrowing) reworking of the sediment, influence the coupling between bacterial functional groups and their degradation capacities?
- Does the community obtained in presence of burrowing organisms produce the same metabolites than that obtained without burrowing organisms?
- Do these communities have similar degradation pathways? Are the same genes (operons) involved?
The DECAPAGE project aims precisely to answer these questions characterizing in depth these bacterial communities and comparing them with those resulting from mechanical reworking that correspond to a mitigation strategy implemented during oil spills.
At the academic point of view, the expected results will allow to understand the adaptation mechanisms driving the reorganization of bacterial communities in response to petroleum. This will help to determine the optimal oxygenation regimes for efficient petroleum degradation, crucial information for the implementation of mitigation strategies.
Project start: 1st November, 2011
Project end: 30 April, 2015