Marine metagenome
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA277357 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Eukaryotes may experience oxygen deprivation under several physiological and pathological conditions. Because oxygen shortage leads to a reduction in cellular energy production, all the eukaryotes studied so far evolved ways to conserve energy via suppression of metabolism. However, the molecular physiology of animals that naturally and repeatedly experience anoxia is poorly studied. One such animal is the symbiotic marine nematode Laxus oneistus. This thrives, invariably coated by its sulfur-oxidizing bacterium Candidatus Thiosymbion oneisti, in anoxic sulfidic or hypoxic sand. Here, by applying transcriptomics and proteomics, we discovered that, irrespective of the oxygen concentration it is subjected to, this nematode is mostly and constitutively engaging in ubiquitination-mediated proteolysis, energy generation, oxidative stress response and immune response. Furthermore, by incubating L. oneistus under sulfidic anoxic or hypoxic conditions, we found that, under the first condition, the worm upregulated genes involved in ribosome biogenesis, proteolytic systems (autophagy and the ubiquitin-proteasome system), chaperones, detoxification and lectins. Degradation pathways were likely induced to recycle damaged cellular components (mitochondria) and misfolded proteins into nutrients, whereas lectins were likely expressed to promote the attachment of its anaerobic, thiotrophic symbiont. Besides, L. oneistus appeared to survive oxygen deprivation by using alternative electron carriers (rhodoquinone) and acceptors (fumarate) to rewire the electron transfer chain. On the other hand, under hypoxia, genes involved in costly processes (e.g., development, amino acid biosynthesis, feeding behaviour, mating) were upregulated. Intriguingly, the worm’s Toll-like innate immunity pathway and a number of immune effectors (e.g., Bacterial Permeability Increasing proteins, fungicides) were upregulated in the presence of oxygen. In conclusion, we hypothesize that L. oneistus survives in anoxic sulfidic sand by overexpressing degradation processes, rewiring oxidative phosphorylation and by reinforcing its coat of bacterial sulfur-oxidizers. In the presence of oxygen, instead, it appears to exploit glycolysis to eat, mate and grow. Moreover, oxygen appears to affect L. oneistus immune system in such way, as to favor specific attachment of its anaerobic partner in anoxia and to produce broad-range antimicrobials when oxygen is present.
2021-11-11 | GSE188619 | GEO
Project description:Marine Oxygen Minimum Zone 200m Viral Community
| PRJNA40793 | ENA
Project description:Marine Oxygen Minimum Zone 90m Viral Community
| PRJNA40791 | ENA
Project description:Chemoautotrophic bacteria from the SUP05 clade often dominate anoxic waters in marine oxygen minimum zones (OMZs) where reduced sulfur can fuel carbon fixation and denitrification. Some members of the SUP05 clade are facultative aerobes that thrive at the boundaries of OMZs where they experience fluctuations in dissolved oxygen (DO). The degree to which SUP05 contribute to nitrate reduction in these regions depends on their sensitivity to oxygen. We evaluated growth and quantified differences in gene expression in Ca. T. autotrophicus strain EF1 from the SUP05 clade under high DO (22 μM), anoxic, and low DO (3.8 μM) concentrations. We show that strain EF1 cells respire oxygen and nitrate and that cells have higher growth rates, express more genes, and fix more carbon when oxygen becomes available for aerobic respiration. Evidence that facultatively aerobic SUP05 are more active and respire nitrate when oxygen becomes available at low concentrations suggests that they are an important source of nitrite across marine OMZ boundary layers.
2020-06-01 | GSE144480 | GEO
Project description:Cceanic oxygen minimum zone raw sequence reads
| PRJNA280940 | ENA
Project description:Eastern South Pacific Oxygen Minimum Zone Metagenome
| PRJNA244680 | ENA
Project description:Microbial eukaryote diversity in the marine oxygen minimum zone off northern Chile
| PRJNA263803 | ENA
Project description:Metagenomic Analysis of Size-fractionated Picoplankton in a Marine Oxygen Minimum Zone
| PRJNA217777 | ENA