Project description:Here, we applied a microarray-based metagenomics technology termed GeoChip 5.0 to examined functional gene structure of microbes in three biomes, including boreal, temperate and tropical area.
Project description:Over 20% of Earth’s terrestrial surface is underlain by permafrost that represents one of the largest terrestrial carbon pools, with an estimated ~1700 Pg of carbon (C) contained in the upper 3 m of permafrost. Models estimate that C release from thawing permafrost might represent the largest new transfer of C from the biosphere to the atmosphere as the climate warms. Here we investigated microbial community phylogeny, genetic functional potential gene expression, and protein production patterns along a natural thaw gradient, including permafrost, the seasonally thawed active layer and nearby thawed thermokarst bog, using a combination of molecular “omics” approaches: metagenomics (MG), metatranscriptomics (MT) and metaproteomics (MP). Highlights from these analyses reveal energy yielding microbial processes and potential strategies for microbial survival in permafrost soils, and linkages between biogeochemical process rates and –omics measurements. The results provide new knowledge about microbial life and activity potential in permafrost, the potential importance of iron reduction as a survival strategy under frozen conditions in mineral soils, and the importance of methanogenesis following thaw. The multi-omics strategy demonstrated here enables better mechanistic understanding of the ecological strategies utilized by soil microbial communities in response to climate change. Associated metagenomics data available at the EBI Metagenomics portal under the accession number <a href="https://www.ebi.ac.uk/metagenomics/projects/SRP052575">SRP052575</a>.
Project description:Low oxygen tensions are often encountered in flooded soils of rice fields by root-associated, strictly respiratory, beta proteobacterium, Azoarcus sp. BH72 which fixes nitrogen only under microaerobic condition. In this study, genome wide oligonucleotide microarrays were used compare the global transcription profile of Azoarcus sp. BH72 under microaerobic condition with cells grown under aerobic condition, both with ammonia as sole nitrogen source. The outcome of this study will provide a better insight about the establishment of this endophyte in the microaerobic environment, probably prevailing inside of the rice root niche . RNA from cells grown under microaerobic condition with 0.3% oxygen (experiment) and aerobic condition with 21% oxygen (control), respectively was used for two color whole genome microarray approach.
Project description:We compared global transcriptional patterns in Pyrobaculum aerophilum cultures with oxygen, nitrate, arsenate and ferric iron as respiratory electron acceptors to identify genes and regulatory patterns that differentiate these pathways. Keywords: Time course study with different respiratory electron acceptors
2009-01-23 | GSE11366 | GEO
Project description:Endophytic fungi from South American temperate rainforest
Project description:Global warming has shifted climate zones poleward or upward. However, understanding the responses and mechanism of microbial community structure and functions relevant to natural climate zone succession is challenged by the high complexity of microbial communities. Here, we examined soil microbial community in three broadleaved forests located in the Wulu Mountain (WLM, temperate climate), Funiu Mountain (FNM, at the border of temperate and subtropical climate zones), or Shennongjia Mountain (SNJ, subtropical climate).Soils were characterized for geochemistry, Illumina sequencing was used to determine microbial taxonomic communities and GeoChips 5.0 were used to determine microbial functional genes.
Project description:Low oxygen tensions are often encountered in flooded soils of rice fields by root-associated, strictly respiratory, beta proteobacterium, Azoarcus sp. BH72 which fixes nitrogen only under microaerobic condition. In this study, genome wide oligonucleotide microarrays were used compare the global transcription profile of Azoarcus sp. BH72 under microaerobic condition with cells grown under aerobic condition, both with ammonia as sole nitrogen source. The outcome of this study will provide a better insight about the establishment of this endophyte in the microaerobic environment, probably prevailing inside of the rice root niche .
Project description:Anaerobic digestion (AD) is a core technology in management of urban organic wastes, converting a fraction of the organic carbon to methane and the residual digestate, the biorest, have a great potential to become a major organic fertilizer for agricultural soils in the future. At the same time, mitigation of N2O-emissions from the agricultural soils is needed to reduce the climate forcing by food production. Our goal was therefore to enrich for N2O reducing bacteria in AD digestates prior to fertilization, and in this way provide an avenue for large-scale and low-cost cultivation of strongly N2O reducing bacteria which can be directly introduced to agricultural soils in large enough volumes to alter the fate of nitrogen in the soils. Gas kinetics and meta-omics (metagenomics and metaproteomics) analyses of the N2O enriched digestates identified populations of N2O respiring organisms that grew by harvesting fermentation intermediates of the methanogenic consortium.
Project description:This series includes a 32-array training dataset used to evaluate E-Predict normalization and similarity metric parameters as well as 13 microarrays used as examples in (Urisman, et. al 2005). Training data set includes 15 independent HeLa RNAhybridizations (microarrays 1-15), 10 independent nasal lavage samples positive for Respiratory Syncytial virus (microarrays 16-25), and 7 independent nasal lavage samples positive for Influenza A virus (microarrays 26-32). Examples iclude a serum sample positive for Hepatitis B virus (microarray 33), a nasal lavage sample positive for both Influenza A virus and Respiratory Syncytial virus (microarray 34), and culture samples of 11 distinct Human Rhinovirus serotypes (microarrays 35-45). Keywords = virus detection, E-Predict, species identification, metagenomics