Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1327578 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Understanding the environmental factors that shape microbial communities is crucial, especially in extreme environments, like Antarctica. Two main forces were reported to influence Antarctic soil microbes: birds and plants. Both birds and plants are currently undergoing unprecedented changes in their distribution and abundance due to global warming. However, we need to clearly understand the relationship between plants, birds and soil microorganisms. We therefore collected rhizosphere and bulk soils from six different sampling sites subjected to different levels of bird influence and colonized by Colobanthus quitensis and Deschampsia antarctica in the Admiralty Bay, King George Island, Maritime Antarctic. Microarray and qPCR assays targeting 16S rRNA genes of specific taxa were used to assess microbial community structure, composition and abundance and analyzed with a range of soil physico-chemical parameters. The results indicated significant rhizosphere effects in four out of the six sites, including areas with different levels of bird influence. Acidobacteria were significantly more abundant in soils with little bird influence (low nitrogen) and in bulk soil. In contrast, Actinobacteria were significantly more abundant in the rhizosphere of both plant species. At two of the sampling sites under strong bird influence (penguin colonies), Firmicutes were significantly more abundant in D. antarctica rhizosphere but not in C. quitensis rhizosphere. The Firmicutes were also positively and significantly correlated to the nitrogen concentrations in the soil. We conclude that the microbial communities in Antarctic soils are driven both by bird and plants, and that the effect is taxa-specific.
2012-06-01 | GSE33847 | GEO
Project description:To investigate the effects of organic fertilizer replacing chemical fertilizer on the growth and development of barley (Kunlun-14), a pot experiment was conducted. The study examined the impacts of different ratios of organic fertilizer replacing chemical fertilizer nitrogen (0%, 40%, 100%, denoted as OFR0, OFR40, OFR100, respectively) on the growth characteristics, leaf carbon-nitrogen balance, and nitrogen metabolism enzyme activities of barley.
2024-12-19 | GSE252277 | GEO
Project description:Cover cropping is an effective method to protect agricultural soils from erosion, promote nutrient and moisture retention, encourage beneficial microbial activity, and maintain soil structure. Reusing winter cover crop root channels with the maize roots during the summer allows the cash crop to extract resources from farther niches in the soil horizon. In this study, we investigate how reusing winter cover crop root channels to grow maize (Zea mays L.) affects the composition and function of the bacterial communities in the rhizosphere using 16S rRNA gene amplicon sequencing and metaproteomics. We discovered that the bacterial community significantly differed among cover crop variations, soil profile depths, and maize growth stages. Re-usage of the root channels increased bacterial abundance, and it further increases as we elevate the complexity from monocultures to mixtures. Upon mixing legumes with brassicas and grasses, the overall expression of several steps of the carbon cycle (C) and the nitrogen cycle (N) improved. The deeper root channels of legumes and brassicas compared to grasses correlated with higher bacterial 16S rRNA gene copy numbers and community roles in the respective variations in the subsoil regimes due to the increased availability of root exudates secreted by maize roots. In conclusion, root channel re-use (monocultures and mixtures) improved the expression of metabolic pathways of the important C and N cycles, and the bacterial communities, which is beneficial to the soil rhizosphere as well as to the growing crops.
2025-05-02 | PXD046832 | Pride
Project description:Elevated atmospheric CO2 can influence the structure and function of rhizosphere microorganisms by altering root growth and the quality and quantity of compounds released into the rhizosphere via root exudation. In these studies we investigated the transcriptional responses of Bradyrhizobium japonicum cells growing in the rhizosphere of soybean plants exposed to elevated atmospheric CO2. The results of microarray analyses indicated that atmospheric elevated CO2 concentration indirectly influences on expression of large number of Bradyrhizobium genes through soybean roots. In addition, genes involved in C1 metabolism, denitrification and FixK2-associated genes, including those involved in nitrogen fixation, microanaerobic respiration, respiratory nitrite reductase, and heme biosynthesis, were significantly up-regulated under conditions of elevated CO2 in the rhizosphere, relative to plants and bacteria grown under ambient CO2 growth conditions. The expression profile of genes involved in lipochitinoligosaccharide Nod factor biosynthesis and negative transcriptional regulators of nodulation genes, nolA and nodD2, were also influenced by plant growth under conditions of elevated CO2. Taken together, results of these studies indicate that growth of soybeans under conditions of elevated atmospheric CO2 influences gene expressions in B. japonicum in the soybean rhizosphere, resulting in changes to carbon/nitrogen metabolism, respiration, and nodulation efficiency.
2010-07-29 | GSE23296 | GEO
Project description:Elevated atmospheric CO2 can influence the structure and function of rhizosphere microorganisms by altering root growth and the quality and quantity of compounds released into the rhizosphere via root exudation. In these studies we investigated the transcriptional responses of Bradyrhizobium japonicum cells growing in the rhizosphere of soybean plants exposed to elevated atmospheric CO2. Transciptomic expression profiles indicated that genes involved in carbon/nitrogen metabolism, and FixK2-associated genes, including those involved in nitrogen fixation, microanaerobic respiration, respiratory nitrite reductase, and heme biosynthesis, were significantly up-regulated under conditions of elevated CO2, relative to plants and bacteria grown under ambient CO2 growth conditions. The expression profile of genes involved in lipochitinoligosaccharide Nod factor biosynthesis and negative transcriptional regulators of nodulation genes, nolA and nodD2, were also influenced by plant growth under conditions of elevated CO2. Taken together, results of these studies indicate that growth of soybeans under conditions of elevated atmospheric CO2 influences gene expressions in B. japonicum in the soybean rhizosphere, resulting in changes to carbon/nitrogen metabolism, respiration, and nodulation efficiency. Bradyrhizobium japonicum strains were grown in the soybean rhizosphere under two different CO2 concentrations. Transcriptional profiling of B. japonicum was compared between cells grown under elevated CO2 and ambient conditions. Four biological replicates of each treatment were prepared, and four microarray slides were used for each strain.
2010-07-28 | E-GEOD-23296 | biostudies-arrayexpress
Project description:Rhodobacter sphaeroides produces hydrogen gas (H2) via its nitrogenase enzyme during photoheterotrophic growth under nitrogen-limited conditions. We find that cells produce different amounts of H2 and show different growth rates, depending on the organic substrate provided (lactate, succinate, glucose, xylose, or glycerol). We used global transcript analyses to determine what genes are involved in the onset of H2 production, and those that lead to different H2 production capacities in cells fed different organic substrates.
2011-08-22 | GSE29811 | GEO
Project description:Organic matter recycling in marine systems is largely driven by microbial processes, particularly in the Arctic where primary production and inputs can be temporally offset from upper trophic level consumption. This study followed bacterial dynamics in the chlorophyll maximum of the Bering Strait and sediment-water interface of the Chukchi Sea using metaproteomic and 16S rRNA methods to measure cellular function and taxonomic composition under low and high marine-derived particulate organic matter (POM) treatments at 0°C. Parallel analysis of major organic components (lipids and amino acids) allowed a comparison of microbial-POM interactions. Over the 10 day experimental period, bacteria under both treatments showed rapid community responses and changes in proteomic expression, accompanied by small changes in the concentration and distributions of organic components. In the Bering Strait community, protein translation was an important immediate cellular response under both POM scenarios while specific metabolic processes were more distinct between treatments. For example, under both conditions, evidence for carboxylic acid metabolism increased at day 6 while carbohydrate utilization as an energy source showed unique patterns as the experiments progressed. With POM additions to the Bering Strait community, nitrogen transport and regulation went up, including nitrogen fixation and ammonia assimilation, by day 6. In addition, a number of vitamin enzymatic cofactors were enriched by this day, providing evidence for an increase in C1 metabolism at that time. Low POM conditions stimulated the cycling and synthesis of amino acids, which was not as pronounced under the high POM treatment. In the Chukchi Sea community, nitrate reduction and substrate-specific transporter activity was statistically higher than in the Bering Strait, especially under low POM conditions. Taxonomic inference revealed that a wide range of bacterial classes were associated with the shifting cellular functions, but that Alphaproteobacteria, Gammaproteobacteria and Flavobacteria controlled most of these protein abundances. Activities of all classes were highly variable, with less dominant bacterial groups exhibiting a particularly strong degree of niche separation.
2019-02-18 | PXD008780 | Pride