Structure and FUNctioning of HYdrocarbon polluted microbial MATs – FUNHYMAT

One of the greatest challenges facing microbiology today is the task of linking taxonomy and function. Understanding the underlying metabolic mechanisms and regulatory networks as integrated units in complex communities is paramount. The comprehension of the mechanisms of microbial community assemblage, ie, the processes affecting the distribution, abundance, demography and interactions of populations, is central to understand the communities’ functioning. The stability and function of these communities require balancing competition and positive interactions among multiple species. The genetic diversity enhances the productivity and sustainability of populations because of positive interactions between community members and because individuals with different requirements use available habitats more effectively, thus extending the range of conditions in which the community will thrive. By this way, diversity lessens the impact of environmental upheaval. However, describing the bacterial assemblage is not informative as to the functioning of the microbial community. Information about the functionality of microbes in their particular environment may give the key to understand the functional diversity of microbial communities and ultimately of ecosystem function as a whole.
Among complex microbial communities, microbial mats exhibit extensive genetic and metabolic diversification, which confers a high capacity to colonize hostile environments. Microbial mats probably are the oldest structured ecosystems on earth, since stromatolithes (microfossils of mats) have been dated to be ~3.5 billion years old. They host different functional interacting groups, creating a network of relationships which determines the mats’ functioning.
In this context, the FUNHYMAT project intends to increase knowledge in the assembly and functioning of microbial mats. The mats that will be investigated are similar except for the level of petroleum contamination, which constitutes the forcing parameter affecting the mats. Microbial mats have been characterized growing on shore lines contaminated after oil spills. Although their biodegradation potential has already been highlighted, currently it is not understand how the complex network characteristic of the mat and its function is affected by the petroleum contamination. The assessment of pollution impact either at functional groups level or at community level is a real challenge to understand the overall response of microbial mats to pollution, therefore the specific assemblage and functioning of the microbial mats will be investigated at both levels.
To further investigate the functioning of a microbial mat and the impact of petroleum hydrocarbons on microbial communities, new approaches will be applied. Recent studies provide evidence that metagenomic and metatranscriptomic investigations of natural microbial communities are not only feasible, but when paired with microbial activity measurements, offer an unprecedented opportunity to explore both structure and function of microbial communities. The application of these combined technologies will bring a new insight of the dynamics and functioning of these complex microbial communities.