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.
Project description:Viral concentrates (VCs) contained both viral particles and cell-affiliated components. In this study, a shotgun metaproteomic approach was applied to characterize proteins in the VCs collected from chlorophyll maximum, mesopelagic (200 m) and bathypelagic (3000 m) waters in the South China Sea. Abundant viral proteins indicated the shift of viral community as depth. Whereas the remaining non-viral proteins suggested the diverse microbial metabolism distinct at different layers.
Project description:Microbial communities respond to temperature with physiological adaptation and compositional turnover. Whether thermal selection of enzymes explains marine microbiome plasticity in response to temperature remains unresolved. By quantifying the thermal behaviour of seven functionally-independent enzyme classes (esterase, extradiol dioxygenase, phosphatase, beta-galactosidase, nuclease, transaminase, and aldo-keto reductase) in native proteomes of marine sediment microbiomes from the Irish Sea to the southern Red Sea, we record a significant effect of the mean annual temperature (MAT) on enzyme’s response (R2, 0.51–0.80, p < 0.01 in all cases). Activity and stability profiles of 228 esterases and 5 extradiol dioxygenases from sediment and seawater across 70 locations worldwide (latitude 62.2°S–16°N, MAT –1.4ºC–29.5ºC) validate this thermal pattern. Modelling the esterase phase transition temperature as a measure of structural flexibility, confirm the observed relationship with MAT. Furthermore, when considering temperature variability in sites with non-significantly different MATs, the broadest range of enzyme thermal behaviour and the highest growth plasticity of the enriched heterotrophic bacteria occur in samples with the widest annual thermal variability. These results indicate that temperature-driven enzyme selection shapes microbiome thermal plasticity and that thermal variability finely tunes such processes and should be considered alongside MAT in forecasting microbial community thermal response