ISOMICS. Interacción entre los contaminantes orgánicos sintéticos y las comunidades microbianas en aguas costeras. CTM2015-65691-R. Spanish Ministry of Economy and Competitiveness. PI: M Vila-Costa. Total amount: 145.000 euros.
Increasing trace amounts of thousands of man-made organic pollutants (OPs) and hydrocarbons reach seawaters mainly through run-off, riverine and diffuse atmospheric inputs. The fraction of marine dissolved organic matter (DOM) accounted by OPs remains unknown due to the analytical complexity to analyse both pools. However, this assessment is important because OPs are hydrophobic, and thus tend to accumulate in marine biota at higher intracellular concentrations than in seawater. Besides bioconcentration, bacterioplankton (the main consumers of DOM) can degrade some OPs as indicated by few
indirect field evidences. Whereas a handful studies have seen an important impact on phytoplankton by the myriad of OP present in seawater (and not when considering just few OPs), the effects of OPs on heterotrophic microorganisms biodiversity and functionality is unknown. The working hypothesis of ISOMICS is that the marine microbial community structure and function is affected by the cocktail of OPs present in seawater, and that microbial degradation is an important, but yet unaccounted oceanic sink of OPs. Recent genomic insights into the metabolic capacities of marine bacteria have revealed specific phylogenetic-based genetic traits, thus suggesting that different bacterial groups might present different sensitivities to pollutants. We propose to combine functional genomic tools with quantitative biogeochemical approaches under manipulated conditions to determine bacteria-mediated OP pool turnover in coastal waters, and to resolve the molecular mechanisms by which key members of marine microbial communities respond to perturbations by OPs.