Electrochemical Nitrate Reduction In marine Sediment – ENIRIS
My current project at VUB, named “Electrochemical Nitrate Reduction In marine Sediment – ENIRIS”, aims to investigate the impact of the recently described “cable bacteria” on the benthic nitrogen cycling. Cable bacteria are filamentous multi-cellular prokaryotes able to couple the oxidation of sulphide at depths of one-two cm in the sediment to the reduction of O2 or NO3- at the sediment surface, by generating electric currents.
Their discovery radically extended our understanding on the physiological capacities of prokaryotes. Especially, their ability to couple half-redox reactions over centimetre distances (thereby bypassing possible intermediate electron acceptors) challenges the paradigm of “redox cascade” (i.e. the subsequential reduction of electron acceptors with decreasing energy yield with depth). Thus, this finding requires scientists to develop new tools and conceptual models to assess the implications of natural electric currents in marine sediments.
Within ENIRIS, using a multidisciplinary approach which incorporates electrochemical, geochemical, and molecular tools, we are investigating how the generation of such natural electric currents alter the nitrogen (and sulphur) cycling in the sediment. I am also engaged in assessing the relevance of cable bacteria metabolism in natural systems.
Find more information on cable bacteria at www.microbial-electricity.eu
ENIRIS has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 656385.
Cable bacteria, nitrogen, sediment
My expertise lies in the field of aquatic biogeochemistry. I am particularly interested in the processes that regulates macronutrient cycling in the benthic environment and in the factors that alter such transformations (e.g. bioturbation, organic matter input, abiotic changes of the physical-chemical environment). In my research, I primarily apply electrochemical and bacterial-based microsensors, planar optode technology, and stable isotopes techniques