Project description:Background: The soil environment is responsible for sustaining most terrestrial plant life on earth, yet we know surprisingly little about the important functions carried out by diverse microbial communities in soil. Soil microbes that inhabit the channels of decaying root systems, the detritusphere, are likely to be essential for plant growth and health, as these channels are the preferred locations of new root growth. Understanding the microbial metagenome of the detritusphere and how it responds to agricultural management such as crop rotations and soil tillage will be vital for improving global food production. Methods: The rhizosphere soils of wheat and chickpea growing under + and - decaying root were collected for metagenomics sequencing. A gene catalogue was established by de novo assembling metagenomic sequencing. Genes abundance was compared between bulk soil and rhizosphere soils under different treatments. Conclusions: The study describes the diversity and functional capacity of a high-quality soil microbial metagenome. The results demonstrate the contribution of the microbiome from decaying root in determining the metagenome of developing root systems, which is fundamental to plant growth, since roots preferentially inhabit previous root channels. Modifications in root microbial function through soil management, can ultimately govern plant health, productivity and food security.
Project description:The microorganisms that colonized in or on hosts play significant roles in regulating host’s immunological fitness and bioenergy production, thus controls the host’s response to stress or foreign stimuli. Since radiation typically causes a pro-inflammatory and bioenergy expensive condition, we speculate that the radiation could influence gut microbial compositions, thereof the host-microbe bidirectional relationship. Pertinent model included exposing the young adult mice to total body irradiation (TBI) at doses of 9.5Gy and 11Gy, respectively. Descending colon contents (DCC) were collected from non-irradiated mice (baseline control), and irradiated mice euthanized on days 1, 3 and 9 post-TBI. DCC’s 16s ribosomal DNAs were screened for bacterial taxonomic classification and bacterial abundance profile informed metagenome-specific biofunctions. A second aliquot of same DCC was screened for untargeted metabolomics assay to find most perturbed metabolite-enriched networks. Dose-independent temporal delay since TBI emerged as the primary factor explaining the increased richness of bacterial community and the diversity of metabolite landscape. Among the mice exposed to 11Gy TBI, an increased abundance of Firmicutes, an anti-inflammatory and efficient energy harvesting bacteria accompanied an increment of pro-inflammatory Deferribacteres. Systems evaluation of the functional networks linked to DCC’s metagenome and metabolite, respectively, suggested a diverging trend between host and DCC microbes in regulating the network clusters, such as lipid metabolism, bioenergy synthesis, particularly at the later time points post-11Gy TBI. This analysis potentially suggested a disrupted symbiotic relationship between the host and microbes when the host became moribund.
Project description:Proteome analysis of the surface matrix of chitinous barrier membranes of the tunicate Ciona intestinalis Type A, a marine filter-feeding invertebrate chordate. This chitinous membrane separate food microbes from the gut epithelium, as a physical barrier. As controls, we used mucus cords from the esophagus.
Project description:In a prior report, we observed two distinct lung microbiomes in healthy subjects that we termed â??pneumotypesâ??: pneumotypeSPT, characterized by high bacterial load and supraglottic predominant taxa (SPT) such as the anaerobes Prevotella and Veillonella; and pneumotypeBPT, with low bacterial burden and background predominant taxa (BPT) found in the saline lavage and bronchoscope. Here, we determined the prevalence of these two contrasting lung microbiome types, in a multi-center study of healthy subjects. We confirmed that a lower airway microbiome enriched with upper airway microbes (pneumotypeSPT) was present in ~45% of healthy individuals. Cross-sectional Multicenter cohort. BAL of 49 healthy subjects from three cohort had their lower airway microbiome assessed by 16S rDNA sequencing and microbial gene content (metagenome) was computationally inferred from taxonomic assignments. The amplicons from total 100 samples are barcoded; the barcode and other clinical characteristics (e.g. inflammatory biomarkers and metabolome data) for each sample are provided in the 'Pneumotype.sep.Map.A1.txt' file.
Project description:Marine sponges are essential for coral reefs to thrive and harbour a diverse microbiome that is thought to contribute to host health. Although the overall function of sponge symbionts has been increasingly described, in-depth characterisation of each taxa remains challenging, with many sponge species hosting up to 3,000 distinct microbial species. Recently, the sponge Ianthella basta has emerged as a model organism for symbiosis research, hosting only three dominant symbionts: a Thaumarchaeotum, a Gammaproteobacterium, and an Alphaproteobacterium and a range of other minor taxa. Here, we retrieved metagenome assembled genomes (MAGs) for >90% of I. basta’s microbial community which allowed us to make a complete metabolic reconstruction of the sponge’s microbiome, identifying metabolic complementarity between microbes, as well as the importance of symbionts present in low abundance. We also mined the metagenomes for putative viral sequences, highlighting the contribution of viruses to the overall metabolism of the sponge, and complement this data with metaproteomic sequencing to identify active metabolic pathways in both prokaryotes and viruses. This data now allows us to use I. basta as a model organism for studying host-microbe interactions and provides a basis for future (genomic) manipulative experiments.