title: Response of Core Microbial Consortia to Chronic Hydrocarbon Contaminations in Coastal Sediment Habitats.
abstract: Traditionally, microbial surveys investigating the effect of chronic anthropogenic pressure such as polyaromatic hydrocarbons (PAHs) contaminations consider just the alpha and beta diversity and ignore the interactions among the different taxa forming the microbial community. Here, we investigated the ecological relationships between the three domains of life (i.e.,Bacteria, Archaea, andEukarya) using 454 pyrosequencing on the 16S rRNA and 18S rRNA genes from chronically impacted and pristine sediments, along the coasts of the Mediterranean Sea (Gulf of Lion, Vermillion coast, Corsica, Bizerte lagoon and Lebanon) and the French Atlantic Ocean (Bay of Biscay and English Channel). Our approach provided a robust ecological framework for the partition of the taxa abundance distribution into 859 core Operational taxonomic units (OTUs) and 6629 satellite OTUs. OTUs forming the core microbial community showed the highest sensitivity to changes in environmental and contaminant variations, with salinity, latitude, temperature, particle size distribution, total organic carbon (TOC) and PAH concentrations as main drivers of community assembly. The core communities were dominated byGammaproteobacteriaandDeltaproteobacteriaforBacteria, byThaumarchaeota, BathyarchaeotaandThermoplasmataforArchaeaandMetazoaandDinoflagellataforEukarya. In order to find associations among microorganisms, we generated a co-occurrence network in which PAHs were found to impact significantly the potential predator - prey relationship in one microbial consortium composed of ciliates andActinobacteria. Comparison of network topological properties between contaminated and non-contaminated samples showed substantial differences in the network structure and indicated a higher vulnerability to environmental perturbations in the contaminated sediments.
authors: Equipe Environnement et Microbiologie, Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux, UMR 5254 Centre National de la Recherche Scientifique - Université de Pau et des Pays de L'Adour Pau, France.
authors: Mathilde
authors: M
authors: Jeanbille
authors: Equipe Environnement et Microbiologie, Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux, UMR 5254 Centre National de la Recherche Scientifique - Université de Pau et des Pays de L'Adour Pau, France.
authors: Jérôme
authors: J
authors: Gury
authors: Equipe Environnement et Microbiologie, Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux, UMR 5254 Centre National de la Recherche Scientifique - Université de Pau et des Pays de L'Adour Pau, France.
authors: Robert
authors: R
authors: Duran
authors: Laboratoire Biogéochimie des Contaminants Organiques, Unité Biogéochimie et Ecotoxicologie, Département Ressources Biologiques et Environnement, Ifremer Centre Atlantique Nantes, France.
authors: Jacek
authors: J
authors: Tronczynski
authors: Littoral, Environnement et Sociétés, UMR 7266 Centre National de la Recherche Scientifique - Université de La Rochelle La Rochelle, France.
authors: Hélène
authors: H
authors: Agogué
authors: Equipe Environnement et Microbiologie, Institut Pluridisciplinaire de Recherche sur l'Environnement et les Matériaux, UMR 5254 Centre National de la Recherche Scientifique - Université de Pau et des Pays de L'AdourPau, France; Laboratoire de Bio-surveillance de l'Environnement, Faculté des Sciences de BizerteZarzouna, Tunisie.
authors: Olfa
authors: O
authors: Ben Saïd
authors: Laboratoire d'Océanographie Microbienne, Sorbonne Universités, UMR 7621, Centre National de la Recherche Scientifique-University Pierre and Marie Curie Banyuls sur mer, France.
authors: Jean-François
authors: JF
authors: Ghiglione
authors: Marine Biodiversity, Exploitation and Conservation, UMR Centre National de la Recherche Scientifique 9190 Montpellier, France.
authors: Jean-Christophe
authors: JC
authors: Auguet
keywords: PAH; chronic contamination; co-occurrence network; coastal sediment; core community; microbial consortia