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Marine Molecular Microbiology

Key interest areas: marine microbiology; microbial interaction networks; DOM cycling; microbial carbon pump and carbon sequestration in the oceans; microbial response to stress; microbial production and function of natural products. My areas of expertise are: molecular biology, proteomics, metabolomics, and molecular ecology.

Current research has three main axes:joseph 2

i) to generate new knowledge on carbon cycling and potential mediation of climate change. Anthropogenic gas emissions and the growing concentration of CO2 in the atmosphere has become one of the main public concerns during the past decades. My research is focussed in gaining knowledge on CO2 sequestration by the oceans and how these become the major sinks of the growing amounts of atmospheric carbon. This process is mainly driven by the microbial carbon pump, were primary producers will fix carbon releasing labile DOM that will become more and more recalcitrant through the microbial food web.

ii) to understand how evolution in stable environments pushes free-living organisms to lose genetically-encoded functions in order to lower their costly maintenance energy. This results in organisms becoming dependent on other members of the community that carry out these dispensable, but still vital, functions within the community as a whole. Therefore, any member of the community that conserves such a vital function will be essential to the rest and be maintained in the consortium. This suggests that in stable marine systems a mutualistic and co-operative consortium will compete as ‘a whole’ during natural selection instead of in an individualistic way. Certainly, the fact that the marine microbial community carries out essential processes as ‘a whole’ and not as an individual is, without doubt, the major reason for the low success rate in culturing marine microbes in the laboratory. However, there is still a dearth of information on a mechanistic understanding of this process and the network of interactions that take place in these systems.

iii) to discover novel natural products for future biotechnological exploitation. Environmental microorganisms represent a huge reservoir of enzymatic and chemical activities that could be useful items for the green chemistry field to produce novel biotechnological products of interest. Research is being conducted on the secreted products of relevant marine micro-organisms which are known for being a prolific, rich and diverse source of novel biochemistry and natural products. These products (antibiotics, probiotics or bactericides) have a wide interest not only for Human health but also for other industrial activities such as fisheries or energy-producing algae plants. Nevertheless, one of the biggest gaps found during the study of these natural products is determining their real function within their natural environment.

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