title: Epsilonproteobacteria dominate bacterial diversity at a natural tar seep.
abstract: The bacterial diversity of a naturally seeping bitumen source was investigated by 16S rRNA gene cloning and sequencing. Epsilonproteobacteria were shown to dominate the bacterial diversity in the underground water and within the bitumen, representing ca. 75% of the total bacterial diversity. These Epsilonproteobacteria were dominated by Sulfurimonas OTUs, while Sulfurovum and Arcobacter OTUs completed the remaining diversity. Epsilonproteobacteria are sulfur-oxidizer, nitrate-reducing chemo-lithoautotrophic bacteria, unable to use most organics for growth but capable of CO2fixation. Thus, reduced sulfur species, but not the complex organic matter of the tar, are utilized for growth by bacterial communities at the Puy-de-la-Poix. The large prevalence of populations of Epsilonproteobacteria is a clear indication that crude oil offers a competitive ecological niche for these organisms.
authors.affiliation: Département de biologie, ENS de Lyon, 69364 Lyon, France; Université de Lyon, ENS de Lyon, CNRS UMR 5276, 69364 Lyon, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Lormières
authors.affiliation: Université de Lyon, ENS de Lyon, CNRS UMR 5276, 69364 Lyon, France; Université de Lyon, INSA Lyon, UCBL, CNRS, UMR5240, 69621 Villeurbanne, France. Electronic address: philippe.oger@insa-lyon.fr.
authors.forename: Phil M
authors.initials: PM
authors.lastname: Oger
mesh_terms: D020565:Epsilonproteobacteria / Q000254:growth & development* / Q000302:isolation & purification; D013638:Tars; D014871:Water Microbiology; D014873:Water Pollutants / Q000737:chemistry
chemical_list: D013638:Tars; D014873:Water Pollutants
keywords: Cycle du soufre; Dégradation du pétrole; Epsilonproteobacteria; Epsilonprotéobactéries; Natural oil seep; Oil degradation; Source de bitume; Sulfur cycle; Sulfurimonas