Project description:We report the full transcriptome (RNA-Seq) of Vibrio fischeri ES114 in rich medium, seawater, and after venting from the Hawaiian bobtail squid Euprymna scolopes. We also report the effects of ribodepletion on low-biomass samples, down to input amount of 1ng total RNA.
Project description:A short-term microcosm experiment was conducted to evaluate the impact of wastewater discharge on coastal microbial communities. Coastal seawater was exposed to two types of treated wastewater: (i) unfiltered wastewater, containing nutrients, pollutants, and allochthonous microbes, and (ii) filtered wastewater, which retained only nutrients and pollutants while removing microbial components. Metaproteomic samples were collected from the coastal seawater prior to the experiment and from each experimental flask at the late exponential growth phase to assess microbial functional responses to wastewater exposure.
Project description:Genetic engineering of filamentous fungi has promise for accelerating the transition to a more sustainable food system and enhancing the nutritional value, sensory appeal, and scalability of microbial foods. However, genetic tools and demonstrated use cases for bioengineered food production by edible strains are lacking. Here, we developed a synthetic biology toolkit for Aspergillus oryzae, an edible fungus traditionally used in fermented foods and currently used in protein production and meat alternatives. Our toolkit includes a CRISPR-Cas9 method for genome integration, neutral loci, and new promoters. We use these tools to enhance the elevate levels of the nutraceutical ergothioneine and intracellular heme in the edible biomass. The biomass overproducing heme is red in color and is readily formulated into imitation meat patties with minimal processing. These findings highlight the promise of genetic approaches to enhance fungal meat alternatives and provide useful engineering tools for diverse applications in fungal food production and beyond.
Project description:Background: Rainbow trout (Oncorhynchus mykiss) is a salmonid species with a complex life-history. Wild populations are naturally divided into freshwater residents and sea-run migrants. Migrants undergo an energy-demanding adaptation for life in seawater, known as smoltification, while freshwater residents display these changes in an attenuated magnitude and rate. Despite this, in seawater rainbow trout farming all animals are transferred to seawater. Under these circumstances, weeks after seawater transfer, a significant portion of the fish die (around 10%) or experience growth stunting (GS; around 10%), which represents an important profitability and welfare issue. The underlying causes leading to GS in seawater-transferred rainbow trout remain unknown. In this study, we aimed at characterising the GS phenotype in seawater-transferred rainbow trout using untargeted and targeted approaches. To this end, the liver proteome (LC-MS/MS) and lipidome (LC-MS) of GS and fast-growing phenotypes were profiled to identify molecules and processes that are characteristic of the GS phenotype. Moreover, the transcription, abundance or activity of key proteins and hormones related to osmoregulation (Gill Na+, K+–ATPase activity), growth (plasma IGF-I, and liver igf1, igfbp1b, ghr1 and ctsl) and stress (plasma cortisol) were measured using targeted approaches. Results: No differences in Gill Na+, K+–ATPase activity and plasma cortisol were detected between the two groups. However, a significant downregulation in plasma IGF-I and liver igf1 transcription pointed at this growth factor as an important pathomechanism for GS. Changes in the liver proteome revealed reactive-oxygen-species-mediated endoplasmic reticulum stress as a key mechanism underlying the GS phenotype. From the lipidomic analysis, key observations include a reduction in triacylglycerols and elevated amounts of cardiolipins, a characteristic lipid class associated with oxidative stress, in GS phenotype. Conclusion: While the triggers to the activation of endoplasmic reticulum stress are still unknown, data from this study point towards either an unresolved infection or a nutritional deficiency as underlying drivers of this phenotype.
Project description:October 2013 surface seawater collected from Monterey Bay was incubated with 1 micromolar 13C labeled glucose, starch, acetate, lipids, protein, or amino acids for 12 hours. Community RNA was extracted and hybridized to a Roche Nimblegen microarray and analyzed by NanoSIMS to obtain isotope ratio data for all probe spots.
Project description:Atlantic salmon (Salmo salar) move from fresh- to seawater environments following a seasonally timed preparative transition called smoltification, which takes place under photoperiodic control in the freshwater environment. In masu salmon (Oncorhynchus masou), coordination of photoperiodic sexual maturation is proposed to involve in a fish-specific circumventricular organ, the saccus vasculosus (SV), through its intrinsic opsin-based light sensitivity, thyrotrophin secretion and modulation of deiodinase activity (TSH-DIO cascade). The saccus vasculosus is a highly vascularized structure located on the ventral side of the hypothalamus and its interface between the blood and cerebrospinal fluid also hints at a role in ionic balance of the cerebrospinal fluid (CSF). Both the potential photoperiodic and ionic functions of the SV led us to perform transcriptome analysis of the SV in smoltification in Atlantic salmon. Our data show that SV response to seawater exposure is highly dependent on photoperiodic history and identifies ependymin as a major secretory output of the SV, consistent with a role in control of CSF composition. Conversely, we could not detect crucial elements of the opsin-TSH-DIO cascade suggesting that the photoperiodic history-dependence of the SV to seawater exposure is unlikely to stem from SV-intrinsic responses to photoperiod.