Project description:The arctic ecosystems are increasingly exposed to pollution particularly from offshore petroleum extraction-related activities. The objective of the study is to map transcriptome responses in copepods of the arctic region in response to PAHs phenanthrene (Phe) and benzo[a]pyrene (BaP) found in crude-oil contaminants.
Project description:The arctic ecosystems are increasingly exposed to pollution particularly from offshore petroleum extraction-related activities. The objective of the study is to map transcriptome responses in copepods of the arctic region in response to PAHs phenanthrene (Phe) and benzo[a]pyrene (BaP) found in crude-oil contaminants.
Project description:The arctic ecosystems are increasingly exposed to pollution particularly from offshore petroleum extraction-related activities. The objective of the study is to map transcriptome responses in copepods of the arctic region in response to PAHs phenanthrene (Phe) and benzo[a]pyrene (BaP) found in crude-oil contaminants.
Project description:An Autonomous Underwater Vehicle (AUV) and large volume underwater pumps were used to collect microbial biomass from offshore waters of the Sargasso Sea, from surface waters and into the deep ocean. Seawater collection was performed along a transect in the western North Atlantic Ocean beginning near Bermuda and ending off the coast of Massachusetts, capturing metabolic signatures from oligotrophic, continental margin, and productive coastal ecosystems.
Project description:Origanum oil (ORO), garlic oil (GAO), and peppermint oil (PEO) were shown to effectively lower methane production, decrease abundance of methanogens, and change abundances of several bacterial populations important to feed digestion in vitro. In this study, the impact of these essential oils (EOs, at 0.50 g/L), on the rumen bacterial community composition was further examined using the recently developed RumenBactArray.
Project description:Although N2 fixation can occur in free-living cyanobacteria, the unicellular endosymbiotic cyanobacterium Candidatus Atelocyanobacterium thalassa (UCYN-A) is considered to be a dominant N2-fixing species in marine ecosystems. Four UCYN-A sublineages are known from partial nitrogenase (nifH) gene sequences. However, few studies have investigated their habitat preferences and regulation by their respective hosts in open-ocean versus coastal environments. Here, we compared UCYN-A transcriptomes from oligotrophic open-ocean versus nutrient-rich coastal waters. UCYN-A1 metabolism was more impacted by habitat changes than UCYN-A2. However, across habitats and sublineages genes for nitrogen fixation and energy production were highly transcribed. Curiously these genes, critical to the symbiosis for the exchange of fixed nitrogen for fixed carbon, maintained the same schedule of diel expression across habitats and UCYN-A sublineages, including UCYN-A3 in the open-ocean transcriptomes. Our results undersore the importance of nitrogen fixation in UCYN-A symbioses across habitats, with consequences for community interaction and global biogeochemical cycles.
Project description:Oil spills have polluted the marine environment for decades and continue to be a major source of polycyclic aromatic hydrocarbons (PAHs) to marine ecosystems around the globe. Although the toxicity of PAHs to fish has been well studied, the combined effects of extreme abiotic factors and oil are poorly understood. Gulf of Mexico killifish Fundulus grandis larvae (< 24 hours post hatch) were exposed to varying environmental conditions (dissolved oxygen 2, 6 ppm; temperature 20, 25, 30°C; and salinity 3, 10, 30 ppt) combined with varying concentrations of high energy water accommodated fractions (HEWAF) (total PAHs 0 – ~ 125 ppb) for a total of 48 h. Larvae survival and development were negatively affected by PAHs, starting with the lowest concentration tested (~15 ppb). High temperature + hypoxia + PAHs resulted in the lowest survival with salinity having little impact on any of the endpoints tested. Expression of the hepatic detoxifying gene cyp1a was highly induced in PAH-exposed larvae, but only under normoxic conditions. A lack of cyp1a induction under hypoxia and PAH exposure could explain the enhanced toxicity observed. This work highlights the need for more studies examining the combined impact of suboptimal water quality parameters in the presence of pollution in fish early life-stages.
Project description:Brown algae (Phaeophyceae) are complex photosynthetic organisms with a very different evolutionary history to green plants, to which they are only distantly related. These seaweeds are the dominant species in rocky coastal ecosystems and they exhibit many interesting adaptations to these, often harsh, environments. The brown algae are also important because they are one of only a very small number of eukaryotic lineages that have evolved complex multicellularity. This work used whole genome tiling array approach to generate a comprehensive transcriptome map of the filamentous seaweed Ectocarpus siliculosus (Dillwyn) Lyngbye, a model organism for the brown algae. Keywords: high-resolution tiling array, brown algae, ectocarpus
Project description:This project addresses the question of impact of oil spills on lung health. Specifically the project will address the general hypothesis, which is upon oil/dispersant respiratory exposure there will be a higher carcinogenic potential of lung tissue.
