Project description:The experiment at three long-term agricultural experimental stations (namely the N, M and S sites) across northeast to southeast China was setup and operated by the Institute of Soil Science, Chinese Academy of Sciences. This experiment belongs to an integrated project (The Soil Reciprocal Transplant Experiment, SRTE) which serves as a platform for a number of studies evaluating climate and cropping effects on soil microbial diversity and its agro-ecosystem functioning. Soil transplant serves as a proxy to simulate climate change in realistic climate regimes. Here, we assessed the effects of soil type, soil transplant and landuse changes on soil microbial communities, which are key drivers in Earth’s biogeochemical cycles.
Project description:This study began with 72 male 4-week-old BALB/c mice. The mice were split evenly into one of four cohorts: Control, River, Pine, and Road. The control mice were raised with standard corn cob bedding whereas the remaining mice were raised with clean bedding amended with 300 mL of one of three different types of soil. The soil exposure continued throughout the experiment, with 300 mL of new soil added with bi-weekly cage changes. The soils used to amend the cage bedding were previously characterized as having high (Pine), medium (River), and low (Road) diversity. The River and Pine soil were collected from Duke Forest and the Road soil was collected adjacent to Highway 15-501 in Chapel Hill, North Carolina. All mice were given a standard diet and the cages were distributed reverse osmosis treated water through a centralized Lixit® system that was fed to each cage in parallel. After 32 days of standard rearing with amended soils, the mice were exposed via oropharyngeal aspiration to either live influenza A (PR8) virus or heat inactivated (HI) virus.
Project description:Genome-wide microarray analysis was performed using RNA extracted from soil cultures of Streptomyces coelicolor A3(2) in the presence or absence of chitin. The vast majority of genes in chitin and amino sugar metabolism, as well as many other genes for carbon and energy, nitrogen and sulfur metabolism, were differentially expressed in response to addition of chitin. Moreover, the gene expressions of eight gene clusters for secondary metabolites were also significantly up-regulated in the chitin amended soil. To reveal the role of a pleiotropic transcriptional regulator, DasR, which has been reported to be involved in regulation of chitin metabolism, antibiotic production and morphological differentiation, the gene expression patterns of wild type and dasR mutant in soil amended with chitin were compared by microarray analysis. The dasR mutation resulted in up-regulation of four antibiotic gene clusters and down-regulation of chitin metabolism.
Project description:Genome-wide microarray analysis was performed using RNA extracted from soil cultures of Streptomyces coelicolor A3(2) in the presence or absence of chitin. The vast majority of genes in chitin and amino sugar metabolism, as well as many other genes for carbon and energy, nitrogen and sulfur metabolism, were differentially expressed in response to addition of chitin. Moreover, the gene expressions of eight gene clusters for secondary metabolites were also significantly up-regulated in the chitin amended soil. To reveal the role of a pleiotropic transcriptional regulator, DasR, which has been reported to be involved in regulation of chitin metabolism, antibiotic production and morphological differentiation, the gene expression patterns of wild type and dasR mutant in soil amended with chitin were compared by microarray analysis. The dasR mutation resulted in up-regulation of four antibiotic gene clusters and down-regulation of chitin metabolism. A study using total RNA extracted from soil cultures of Streptomyces ceolicolor A3(2). A whole genome microarray of S. coelicolor (NimbleGen Custom Prokaryotic Gene Expression 72K 4-plex Arrays) was designed and manufactured by Roche (Roche NimbleGen, Madison, WI). Each array contained four sets of 8 sequence-specific 60-mer probes per gene corresponding to 7825 genes from the S. coelicolor A3(2) genome.
Project description:Little progress has been made in studying the toxicity of realistic 'non-pristine' forms of nanoparticles that presents in real soil environment. It is presently unkown whether the transformed nanoparticles in realistic environment exerts an adverse effect to rhizobium-legume symbiosis on molecular level. We used microarray to investigate the toxicogenomic responses of the model legume Medicago truncatula following 30 days exposure to three different types of biosolids (control biosolids (control BS), a mixture of Ag, ZnO and TiO2 manufactured nanomaterials added biosolids (Nano BS) and a corresponding bulk metals added biosolids (Bulk BS) ) amended soil that were aged for 6 months prior to exposure in pot experiment.
Project description:Cropping soils vary in extent of natural suppression of soil-borne plant diseases. However, it is unknown whether similar variation occurs across pastoral agricultural systems. We examined soil microbial community properties known to be associated with disease suppression across 50 pastoral fields varying in management intensity. The composition and abundance of the disease-suppressive community were assessed from both taxonomic and functional perspectives.
