Ontology highlight
ABSTRACT:
PROVIDER: PRJNA884624 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Anaerobic ammonium oxidizing (anammox) bacteria mediate a key step in the biogeochemical nitrogen cycle and have been applied worldwide for the energy-efficient removal of nitrogen from wastewater. However, outside their core energy metabolism, little is known about the metabolic networks driving anammox bacterial anabolism and mixotrophy beyond genome predictions. Here, we experimentally resolved the central carbon metabolism using metabolomics (LC-MS and GC-MS), metabolic flux analysis and proteomics (shot-gun proteomics).
2021-07-30 | PXD016171 | Pride
Project description:Effect of phosphorus limitation on the anammox process under different nitrogen concentrations
| PRJDB16520 | ENA
Project description:Phosphorus is a critical nutrient controlling phytoplankton growth. Availability of this limiting factor can vary significantly in space and time, particularly in dynamic aquatic ecosystems. Diatoms are important eukaryotic phytoplankton that thrive in regions of pulsed phosphate supply, yet little is known of the sensory mechanisms enabling them to detect and rapidly respond to phosphorus availability. Here we show that phosphorus-starved diatoms utilise a novel Ca2+-dependent signalling pathway to sense and regulate cellular recovery following phosphorus resupply. This pathway, which has not previously been described in eukaryotes, is sensitive to sub-micromolar concentrations of phosphate, alongside a range of environmentally relevant phosphorus forms. Using comparative proteomics, we have characterised early adaptations governing diatom cellular recovery from phosphorus limitation. Strikingly, the dominant response was substantial enhancement of nitrogen assimilation proteins. This led to 12-fold increases in absolute nitrate uptake rates, relative to phosphorus-starved cells. Moreover, we find that the novel phosphorus-Ca2+ signalling pathway controls this primary recovery response. Our findings highlight that fundamental cross-talk between the essential nutrients phosphorus and nitrogen drive diatom recovery from phosphorus limitation. Moreover, a novel Ca2+-dependent phosphorus signalling pathway governs such ecological acclimation responses, and is thus likely critical to the success of diatoms in regions of episodic nutrient supply.
2021-02-22 | PXD022586 | Pride
Project description:The community composition (in terms of abundance, distribution and contribution of diverse clades) of bacteria involved in nitrogen transformations in the oxygen minimum zones may be related to the rates of fixed N loss in these systems. The abundance of both denirifying and anammox bacteria, and the assemblage composition of denitrifying bacteria were investigated in the Eastern Tropical South Pacific and the Arabian Sea using assays based on molecular markers for the two groups of bacteria. The abundance and distribution of bacteria associated with the fixed N removal processes denitrification and anammox were investigated using quantitative PCR for genes encoding nitrite reductase (nirK and nirS) in denitrifying bacteria and hydrazine oxidase(hzo) and 16S rRNA genesin anammox bacteria. All of these genes had depth distributions with maxima associated with the secondary nitrite maximum in low oxygen waters. NirS was mch more abundant than nirK, and much more abundant than the 16S rRNA gene from anammox bacteria. The ratio of hzo:16S rRNA for anammox was low and variable implying greater unexplored diversity in the the hzo gene. Assemblage composition of the abundant nirS-type denitrifiers was evaluated using a funcitonal gene microarray. Of the nirS archetypes represented on the microarray, very few occurred speficically in one region or depth interval, but the assemblages varied significantly. Community composition of denitrifiers based on microarray analysis of the nirS gene was most different between geographical regions. Within each region, the surface layer and OMZ assemblages clustered distinctly. Thus, in addition to spatial and temporal variation in denitrificaiton and anammox rates, both microbial abundance and community composition also vary between OMZ regions and depths.
2013-09-12 | GSE50787 | GEO
Project description:Coastal marine sediments, as locations of substantial fixed nitrogen loss, are very important to the nitrogen budget and to the primary productivity of the oceans. Coastal sediment systems are also highly dynamic and subject to periodic natural and anthropogenic organic substrate additions. The response to organic matter by the microbial community involved in nitrogen loss processes was evaluated using mesocosms of Chesapeake Bay sediments. Over the course of a 50-day incubation, rates of anammox and denitrification were measured weekly using 15N tracer incubations, and samples were collected for genetic analysis. Rates of both nitrogen loss processes and gene abundances associated with them corresponded loosely, probably because heterogeneities in sediments obscured a clear relationship. The rates of denitrification were stimulated more by the higher organic matter addition, and the fraction of nitrogen loss attributed to anammox slightly reduced. Furthermore, the large organic matter pulse drove a significant and rapid shift in the denitrifier community as determined using a nirS microarray, indicating the diversity of these organisms plays an essential role in responding to anthropogenic inputs. We also suggest that the proportion of nitrogen loss due to anammox in these coastal estuarine sediments may be underestimated due to temporal dynamics as well as from methodological artifacts related to conventional sediment slurry incubation approaches.
2015-01-30 | GSE65430 | GEO