Project description:We designed a new specific mRNA microarray targeting a subset of genes (748) of the diazotrophs Richelia intracellularis and Calothrix rhizosoleniae (genomes RintRC01, RintHH01, RintHM01 and CalSC01) which associate with diatom hosts. The aim was to be able to describe the gene expressions of genes related to several metabolic pathways and how they possibly differed between the closely related strains based on environment and host association. To better understand how the different environments might affect gene expressions, the samples were taken in depth profiles, at night and day, during a cruise in the South China Sea.
Project description:Recent studies have unveiled the deep sea as a rich biosphere, populated by species descended from shallow-water ancestors post-mass extinctions. Research on genomic evolution and microbial symbiosis has shed light on how these species thrive in extreme deep-sea conditions. However, early adaptation stages, particularly the roles of conserved genes and symbiotic microbes, remain inadequately understood. This study examined transcriptomic and microbiome changes in shallow-water mussels Mytilus galloprovincialis exposed to deep-sea conditions at the Site-F cold seep in the South China Sea. Results reveal complex gene expression adjustments in stress response, immune defense, homeostasis, and energy metabolism pathways during adaptation. After 10 days of deep-sea exposure, shallow-water mussels and their microbial communities closely resembled those of native deep-sea mussels, demonstrating host and microbiome convergence in response to adaptive shifts. Notably, methanotrophic bacteria, key symbionts in native deep-sea mussels, emerged as a dominant group in the exposed mussels. Host genes involved in immune recognition and endocytosis correlated significantly with the abundance of these bacteria. Overall, our analyses provide insights into adaptive transcriptional regulation and microbiome dynamics of mussels in deep-sea environments, highlighting the roles of conserved genes and microbial community shifts in adapting to extreme environments.
Project description:In the present study, we studied microbial composition and metabolic activity in the bathypelagic zone of the South China Sea. 12 samples were collected and subjected to metaproteomic analysis. Our data provide a novel view of the roles of two lifestyle prokaryotes and their link in substrate utilization in dark ocean.
Project description:In the present study, we studied microbial composition and metabolic activity in the euphotic zone of the South China Sea. 8 samples were collected and subjected to metaproteomic analysis. Our results suggested that mixotrophic phototrophs-driven NDL carbon fixation along with phytoplankton-driven NRL carbon fixation determined primary production in the oligotrophic ocean’s euphotic zone.
Project description:we applied metaproteomic approach to capture proteins from three size-fractionated microbial communities at the DCM in the basin of the South China Sea. The deep recovery of proteomes from a marine DCM plankton assemblage provides the highest resolution of metabolic activities as well as microbial niche differentiation, revealing a spectrum of biological processes carrying out by microbes at DCM of the SCS.
