Project description:Jellyfish blooms represent a significant, but largely overlooked, source of labile organic matter (jelly-OM) in the ocean, characterized by high protein content with a low C:N ratio. The bloom-decay cycle of jellyfish in coastal waters are important vehicles for carbon export to the ocean’s interior. To accurately incorporate them into biogeochemical models, the interactions between microbes and jelly-OM have yet to be fully characterized. We conducted jelly-OM enrichment experiments to simulate the scenario experienced by the coastal microbiome after the decay of a jellyfish bloom. We combined metagenomics, endo- and exo-metaproteomic approaches to obtain a mechanistic understanding on the metabolic network operated by the jelly-OM degrading bacterial consortium.
Project description:The scyphozoan jellyfish Nemopilema nomurai are common blooming species in China.The venomous characteristics of jellyfish Nemopilema nomurai is largely attributed to their complex and elaborate venom delivery system: the stinging cells, or nematocytes. These specialized cells synthesize and secrete unique intracellular organelles called nematocysts. Nematocysts with heterogeneous sizes and morphologies may contain different toxic components that exert diverse pharmacological and physiological activities such as hemolysis, cytolysis and proteolysis for defense and prey capture. We modified the previous method of nematocyst preparation using density centrifugation to purify undischarged nematocysts from jellyfish Nemopilema nomurai tentacles. Ultimately, isorhiza-type were successfully purified.Then we used purified nematocysts for proteomic study to identify sting-related toxins in Nemopilema nomurai nematocysts.
Project description:The scyphozoan jellyfish Cyanea capillata are common blooming species in China.The venomous characteristics of jellyfish Cyanea capillata is largely attributed to their complex and elaborate venom delivery system: the stinging cells, or nematocytes. These specialized cells synthesize and secrete unique intracellular organelles called nematocysts. Nematocysts with heterogeneous sizes and morphologies may contain different toxic components that exert diverse pharmacological and physiological activities such as hemolysis, cytolysis and proteolysis for defense and prey capture. We modified the previous method of nematocyst preparation using density centrifugation to purify undischarged nematocysts from jellyfish Cyanea capillata tentacles. Ultimately, mastigophore-type nematocysts were successfully purified.Then we used purified nematocysts for proteomic study to identify sting-related toxins in Cyanea capillata nematocysts.
Project description:<p>Symbiotic microorganisms play an important role in the growth and development of marine invertebrates, such as the sea moon, affecting their metamorphosis process. The outbreak of jellyfish puts pressure on marine ecosystems and affects their stability. However, researches on the development of jellyfish are still fewer, the use of biological control of jellyfish disaster is still in the theoretical stage, and the inhibition mechanism of microorganisms on jellyfish remains to be revealed. We isolated a strain of <em>Bacillus paramycoides</em> SG15 from rhizosphere sediments of seagrass <em>Zostera japonica</em>, and found that this strain could inhibit the asexual reproduction of jellyfish <em>Aurelia coerulea</em> polyp larva. Through co-culture experiments, we used transcriptomics, metabolomics and fluorescence in situ hybridization techniques, combined with the genome and metabolome of SG15, and found that this isolate could inhibit the asexual reproduction rate of the larva polyp by inhibiting the absorption of vitamins, and the endoderm cells were the most important action site of SG15. Although there are relatively high concentrations of vitamins and their derivatives in the surrounding environment, the transport of hydra is reduced, and most vitamins cannot be synthesized in the polys as well, thus affecting the growth and reproduction of polyps. Our study, analyzed the interaction processes between Bacillus and polyps and revealed the inhibiting mechanism of the polyp asexual reproduction by <em>B. paramycoides</em> SG15, which laid a theoretical foundation for the subsequent analysis of interactions between jellyfish and microorganisms, bring materials for the biological control of jellyfish disasters.</p><p><br></p><p><strong>Polyps culture media</strong> is reported in the current study <a href='https://www.ebi.ac.uk/metabolights/MTBLS9419' rel='noopener noreferrer' target='_blank'><strong>MTBLS9419</strong></a>.</p><p><strong>Polyps whole organism</strong> is reported in <a href='https://www.ebi.ac.uk/metabolights/MTBLS9409' rel='noopener noreferrer' target='_blank'><strong>MTBLS9409</strong></a>.</p>