Project description:Samples of oil and production water were collected from five wells of the Qinghai Oilfield, China, and subjected to GeoChip hybridization experiments for microbial functional diversity profiling. Unexpectedly, a remarkable microbial diversity in oil samples, which was higher than that in the corresponding water samples, was observed, thus challenging previously believed assumptions about the microbial diversity in this ecosystem. Hierarchical clustering separated oil and water samples, thereby indicating distinct functional structures in the samples. Genes involved in the degradation of hydrocarbons, organic remediation, stress response, and carbon cycling were significantly abundant in crude oil, which is consistent with their important roles in residing in oil. Association analysis with environmental variables suggested that oil components comprising aromatic hydrocarbons, aliphatic hydrocarbons, and a polar fraction with nitrogen-, sulfur-, and oxygen-containing compounds were mainly influential on the structure of the microbial community. Furthermore, a comparison of microbial communities in oil samples indicated that the structures were depth/temperature-dependent. To our knowledge, this is the first thorough study to profile microbial functional diversity in crude oil samples.
Project description:Samples of oil and production water were collected from five wells of the Qinghai Oilfield, China, and subjected to GeoChip hybridization experiments for microbial functional diversity profiling. Unexpectedly, a remarkable microbial diversity in oil samples, which was higher than that in the corresponding water samples, was observed, thus challenging previously believed assumptions about the microbial diversity in this ecosystem. Hierarchical clustering separated oil and water samples, thereby indicating distinct functional structures in the samples. Genes involved in the degradation of hydrocarbons, organic remediation, stress response, and carbon cycling were significantly abundant in crude oil, which is consistent with their important roles in residing in oil. Association analysis with environmental variables suggested that oil components comprising aromatic hydrocarbons, aliphatic hydrocarbons, and a polar fraction with nitrogen-, sulfur-, and oxygen-containing compounds were mainly influential on the structure of the microbial community. Furthermore, a comparison of microbial communities in oil samples indicated that the structures were depth/temperature-dependent. To our knowledge, this is the first thorough study to profile microbial functional diversity in crude oil samples. From the Qinghai Oilfield located in the Tibetan Plateau, northwest China, oil production mixtures were taken from four oil production wells (No. 813, 516, 48 and 27) and one injection well (No. 517) in the Yue-II block. The floating oil and water phases of the production mixtures were separated overnight by gravitational separation. Subsequently, the microbial community and the characteristics of the water solution (W813, W516, W48, and W27) and floating crude oil (O813, O516, O48, and O27) samples were analyzed. A similar analysis was performed with the injection water solution (W517).
Project description:Crude oil is the one of the most important natural assets of humankind, yet it is a major environmental pollutant, in particular, in marine environments. One of the largest crude oil polluted areas in the word is the semi-enclosed Mediterranean Sea, where the metabolic potential of indigenous populations towards the chronic pollution at a large scale is yet to be defined, particularly in anaerobic and micro-anaerobic marine sites. Here, we provided a novel insight into the active microbial metabolism in sediments from three environments along the coastline of Italy. Microbial proteomes exhibited prevalence in anaerobic metabolism, not related to the biodegradation directly, suggesting the strong limitation by oxygen induced by the carbon overload. They also point at previously unrecognized metabolic coupling between methane and methanol utilizers as well as sulfur reducers in marine petroleum polluted sediments.
Project description:The application of chemical dispersants during marine oil spills can affect the community composition and activity of native marine microorganisms. Several studies have indicated that certain marine hydrocarbon-degrading bacteria, such as Marinobacter spp., can be inhibited by chemical dispersants, resulting in lower abundances and/or reduced hydrocarbon-biodegradation rates. In this respect, a major knowledge gap exists in understanding the mechanisms underlying these observed physiological effects. Here, we performed comparative proteomics of the Deepwater Horizon isolate Marinobacter sp. TT1 grown under different conditions that varied regarding the supplied carbon sources (pyruvate vs. n-hexadecane) and whether or not dispersant (Corexit EC9500A) was added, or that contained crude oil in the form of a water-accommodated fraction (WAF) or chemically-enhanced WAF (CEWAF). We characterized the proteins associated with alkane metabolism and alginate biosynthesis in strain TT1, report on its potential for aromatic hydrocarbon biodegradation and present a proposed metabolism of Corexit components as carbon substrates for the strain. Our findings implicate Corexit in affecting hydrocarbon metabolism, chemotactic motility, biofilm formation, and inducing solvent tolerance mechanisms like efflux pumps in strain TT1. This study provides novel insights into dispersant impacts on microbial hydrocarbon degraders that should be taken into consideration for future oil spill response actions.
Project description:To reveal the potential effects of oil and oil dispersants on the respiratory system at the molecular level, we evaluated the transcriptomic profile of human airway epithelial cells grown under treatment of crude oil, the dispersants Corexit 9500 and Corexit 9527 and oil-dispersant mixtures. We identified a very strong effect of Corexit 9500 treatment, with 84 genes (response genes) differentially expressed in treatment vs. control samples. We discovered an interactive effect of oil + dispersant mixtures; while no response gene was found for Corexit 9527 treatment alone, cells treated with Corexit 9527 + oil mixture showed an increased number of response genes (46 response genes), suggesting a synergic effect of 9527 with oil on the transcriptomic perturbation of airway epithelial cells. Through GO (gene ontology) functional term and pathway-based analysis, we identified upregulation of genes involved in angiogenesis and immune responses and downregulation of genes involved in cell junctions and steroid synthesis as the prevailing transcriptomic signatures in the cells treated with Corexit 9500, oil or Corexit 9500 + oil mixture. Interestingly, these key molecular features coincide with those observed in common lung diseases, such as asthma, cystic fibrosis and chronic obstructive pulmonary disease. Our study provides mechanistic insights into the detrimental effects of oil and oil dispersants to the respiratory system and suggested significant health impacts of the recent BP oil spill to those people involved in the cleaning operation.
2017-08-24 | GSE70909 | GEO
Project description:Stimulation of crude oil biodegradation via methanogenesis in depleted oil reservoirs
| PRJNA393031 | ENA
Project description:crude oil degrading microbial community
Project description:In order to explore the bacteriostatic mechanism of Neolamarckia cadamba essential oil, the effect of Neolamarckia cadamba essential oil on microbial transcription in logarithmic growth phase was determined.
Project description:A significant part of the heavier petroleum fraction resulting from offshore oil-spills sinks to the deep-sea. Its fate and biodegradation by microbial communities is unclear. In particular, the physiological and metabolic features of hydrostatic pressure (HP) adapted oil-degraders have been neglected. In this study, hydrocarbon-free sediment from 1km below surface water (bsl) was incubated at 0.1, 10 and 20MPa (equivalent to surface waters, 1 and 2km bsl) using triacontane (C30) as sole carbon source for a 3-month enrichment period. HP strongly impacted biodegration, as it selected for microbial communities with small cells, high O2 respiration and nutrients requirements, but low biomass and C30-degradation yields. The alkane-degrading metaproteome linked to β-oxidation was detected but its expression was reduced under HP contrary to several housekeeping genes. This was reflected in the enriched communities, as atmospheric pressure was dominated by hydrocarbonoclastic bacteria while non-specialized or previously unrecognized oil-degrading genera were enriched under HP.
2018-12-19 | PXD004328 | Pride
Project description:Temporal biodegradation of crude oil and Corexit 9500 in Arctic seawater