title: Microbial oil-degradation under mild hydrostatic pressure (10 MPa): which pathways are impacted in piezosensitive hydrocarbonoclastic bacteria?
abstract: Oil spills represent an overwhelming carbon input to the marine environment that immediately impacts the sea surface ecosystem. Microbial communities degrading the oil fraction that eventually sinks to the seafloor must also deal with hydrostatic pressure, which linearly increases with depth. Piezosensitive hydrocarbonoclastic bacteria are ideal candidates to elucidate impaired pathways following oil spills at low depth. In the present paper, we tested two strains of the ubiquitous Alcanivorax genus, namely A. jadensis KS_339 and A. dieselolei KS_293, which is known to rapidly grow after oil spills. Strains were subjected to atmospheric and mild pressure (0.1, 5 and 10 MPa, corresponding to a depth of 0, 500 and 1000 m, respectively) providing n-dodecane as sole carbon source. Pressures equal to 5 and 10 MPa significantly lowered growth yields of both strains. However, in strain KS_293 grown at 10 MPa CO2 production per cell was not affected, cell integrity was preserved and PO4(3-) uptake increased. Analysis of its transcriptome revealed that 95% of its genes were downregulated. Increased transcription involved protein synthesis, energy generation and respiration pathways. Interplay between these factors may play a key role in shaping the structure of microbial communities developed after oil spills at low depth and limit their bioremediation potential.
authors.affiliation: Laboratory of Microbial Ecology and Technology (LabMET), University of Gent, Coupure Links 653, B 9000 Gent, Belgium.
authors.forename: Alberto
authors.initials: A
authors.lastname: Scoma
authors.affiliation: Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milano, Via Celoria 2, 20133, Milano, Italy.
authors.forename: Marta
authors.initials: M
authors.lastname: Barbato
authors.affiliation: Laboratory of Microbial Ecology and Technology (LabMET), University of Gent, Coupure Links 653, B 9000 Gent, Belgium.
authors.forename: Emma
authors.initials: E
authors.lastname: Hernandez-Sanabria
authors.affiliation: Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milano, Via Celoria 2, 20133, Milano, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Mapelli
authors.affiliation: King Abdullah University of Science and Technology (KAUST), Biological and Environmental Sciences and Engineering Division, Thuwal 23955-6900, Kingdom of Saudi Arabia.|Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milano, Via Celoria 2, 20133, Milano, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Daffonchio
authors.affiliation: Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milano, Via Celoria 2, 20133, Milano, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Borin
authors.affiliation: Laboratory of Microbial Ecology and Technology (LabMET), University of Gent, Coupure Links 653, B 9000 Gent, Belgium.
authors.forename: Nico
authors.initials: N
authors.lastname: Boon
mesh_terms: D053521:Alcanivoraceae / Q000145:classification / Q000235:genetics / Q000378:metabolism; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001673:Biodegradation, Environmental; D017753:Ecosystem; D020869:Gene Expression Profiling / Q000379:methods; D015964:Gene Expression Regulation, Bacterial; D019015:Geologic Sediments / Q000382:microbiology; D006838:Hydrocarbons / Q000378:metabolism; D006874:Hydrostatic Pressure; D053858:Metabolic Networks and Pathways / Q000235:genetics; D010578:Petroleum / Q000378:metabolism*; D059392:Petroleum Pollution; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism; D012343:RNA, Transfer / Q000235:genetics; D012269:Ribosomal Proteins / Q000235:genetics / Q000378:metabolism; D012623:Seawater / Q000382:microbiology; D013045:Species Specificity; D013053:Spectrophotometry
chemical_list: D001426:Bacterial Proteins; D006838:Hydrocarbons; D010578:Petroleum; D012329:RNA, Bacterial; D012269:Ribosomal Proteins; D012343:RNA, Transfer