Search

Jellyfish, microorganisms, and the marine environment collectively shape a complex ecosystem. This study aimed to analyze the microbial communities associated with five jellyfish species, exploring their composition, diversity, and relationships. Microbial diversity among the species was assessed using 16S rRNA gene sequencing and QIIME analysis. Significant differences in bacterial composition were found, with distinct dominant taxa in each species: Mycoplasmataceae (99.21%) in Aurelia coerulea, Sphingomonadaceae (22.81%) in Cassiopea andromeda, Alphaproteobacteria_unclassified (family level) (64.09%) in Chrysaora quinquecirrha, Parcubacteria_unclassified (family level) (93.11%) in Phacellophora camtschatica, and Chlamydiaceae (35.05%) and Alphaproteobacteria_unclassified (family level) (38.73%) in Rhopilema esculentum. C. andromeda showed the highest diversity, while A. coerulea exhibited the lowest. Correlations among dominant genera varied, including a positive correlation between Parcubacteria_unclassified (genus level) and Chlamydiaceae_unclassified (genus level). Genes were enriched in metabolic pathways and ABC transporters. The most abundant potential pathogens at the phylum level were Proteobacteria, Tenericutes, Chlamydiae, and Epsilonbacteraeota. The differing microbial compositions are likely influenced by species and their habitats. Interactions between jellyfish and microorganisms, as well as among microorganisms, showed interdependency or antagonism. Most microbial gene functions focused on metabolic pathways, warranting further study on the relationship between pathogenic bacteria and these pathways.

Objective: To investigate the effects of simulated nitrogen-oxygen saturation exposure at a water depth of 50 m on the expression of inflammatory mediators including interleukin-6 (IL-6), interleukin-10 (IL-10), and tumor necrosis factor-alpha (TNF-α) in the external auditory canal (EAC) of rabbits., Methods: Two batches of New Zealand rabbits were exposed to nitrogen-oxygen saturated at a water depth of 50 m. After exposure, the epithelial tissue in the EAC was analyzed using hematoxylin-eosin (HE) staining, and the changes in expression of inflammatory mediators including IL-6, IL-10, and TNF-α in the EAC of rabbits were determined by real-time polymerase chain reaction (PCR)., Results: According to the result of HE staining, more inflammatory cell infiltration, small vascular congestion, and mucosal edema in the EAC of rabbits were observed in the exposure group than in the control group. Additionally, compared with the control group, the exposure group had increased expression of IL-6 and TNF-α and reduced expression of IL-10 in the EAC of rabbits according to the result of real-time PCR., Conclusion: The nitrogen-oxygen saturation exposure at a water depth of 50 m can cause inflammatory injuries in the EAC of rabbits. The mechanism may be associated with increased expression of IL-6 and TNF-α and reduced expression of IL-10.