Project description:The relative contribution of genetic and environmental factors to variation in immune response is still poorly understood. Here, we performed a deep phenotypic analysis of immunological parameters and molecular profiles of laboratory mice released into an outdoor enclosure, carrying genetic susceptibility genes (Nod2 and Atg16l1) implicated in the development of inflammatory bowel diseases. Differences in lymphocyte populations were largely driven by the lab and wild environment. However, cytokine production after stimulation with microbial antigens showed a stronger genetic component in the lab, which was reduced after exposure to the wild environment. Multi-omic models identified key transcriptional factors associated with lymphocyte changes predictive of the environment, as well as sub-networks associated with cytokine responses against Candida albicans and Bacteroides vulgatus. Hence, exposing laboratory mice of different genetic backgrounds to the outdoor environment may identify important contributors to immune variation.
Project description:The metagenomes of complex microbial communities are rich sources of novel biocatalysts. We exploited the metagenome of a mixed microbial population for isolation of more than 15 different genes encoding novel biocatalysts by using a combined cultivation and direct cloning strategy. A 16S rRNA sequence analysis revealed the presence of hitherto uncultured microbes closely related to the genera Pseudomonas, Agrobacterium, Xanthomonas, Microbulbifer, and Janthinobacterium. Total genomic DNA from this bacterial community was used to construct cosmid DNA libraries, which were functionally searched for novel enzymes of biotechnological value. Our searches in combination with cosmid sequencing resulted in identification of four clones encoding 12 putative agarase genes, most of which were organized in clusters consisting of two or three genes. Interestingly, nine of these agarase genes probably originated from gene duplications. Furthermore, we identified by DNA sequencing several other biocatalyst-encoding genes, including genes encoding a putative stereoselective amidase (amiA), two cellulases (gnuB and uvs080), an alpha-amylase (amyA), a 1,4-alpha-glucan branching enzyme (amyB), and two pectate lyases (pelA and uvs119). Also, a conserved cluster of two lipase genes was identified, which was linked to genes encoding a type I secretion system. The novel gene aguB was overexpressed in Escherichia coli, and the enzyme activities were determined. Finally, we describe more than 162 kb of DNA sequence that provides a strong platform for further characterization of this microbial consortium.
Project description:The Arecibo Observatory (AO) located in Arecibo, Puerto Rico, is the most sensitive, powerful and active planetary radar system in the world [1]. One of its principal components is the 305 m-diameter spherical reflector dish (AORD), which is exposed to high frequency electromagnetic waves. To unravel the microbial communities that inhabit this environment, soil samples from underneath the AORD were collected, DNA extracted, and sequenced using Illumina MiSeq. Taxonomic and functional profiles were generated using the MG-RAST server. The most abundant domain was Bacteria (91%), followed by Virus (8%), Archaea (0.9%) and Eukaryota (0.9%). The most abundant phylum was Proteobacteria (54%), followed by Actinobacteria (8%), Bacteroidetes (5%) and Firmicutes (4%). In terms of functions, the most abundant among the metagenome corresponded to phages, transposable elements and plasmids (16%), followed by clustering-based subsystems (11%), carbohydrates (10%), and amino acids and derivatives (9%). This is the first soil metagenomic dataset from dish antennas and radar systems, specifically, underneath the AORD. Data can be used to explore the effect of high frequency electromagnetic waves in soil microbial composition, as well as the possibility of finding bioprospects with potential biomedical and biotechnological applications.
Project description:Soil microbial communities contain the highest level of prokaryotic diversity of any environment, and metagenomic approaches involving the extraction of DNA from soil can improve our access to these communities. Most analyses of soil biodiversity and function assume that the DNA extracted represents the microbial community in the soil, but subsequent interpretations are limited by the DNA recovered from the soil. Unfortunately, extraction methods do not provide a uniform and unbiased subsample of metagenomic DNA, and as a consequence, accurate species distributions cannot be determined. Moreover, any bias will propagate errors in estimations of overall microbial diversity and may exclude some microbial classes from study and exploitation. To improve metagenomic approaches, investigate DNA extraction biases, and provide tools for assessing the relative abundances of different groups, we explored the biodiversity of the accessible community DNA by fractioning the metagenomic DNA as a function of (i) vertical soil sampling, (ii) density gradients (cell separation), (iii) cell lysis stringency, and (iv) DNA fragment size distribution. Each fraction had a unique genetic diversity, with different predominant and rare species (based on ribosomal intergenic spacer analysis [RISA] fingerprinting and phylochips). All fractions contributed to the number of bacterial groups uncovered in the metagenome, thus increasing the DNA pool for further applications. Indeed, we were able to access a more genetically diverse proportion of the metagenome (a gain of more than 80% compared to the best single extraction method), limit the predominance of a few genomes, and increase the species richness per sequencing effort. This work stresses the difference between extracted DNA pools and the currently inaccessible complete soil metagenome.
Project description:Nine Curtobacterium strains (three from three clades) were subjected to a lab desiccation experiment with no access to moisture or nutrients to compare between clades. RNA was extracted at days 0, 1, and 32 and sequenced
Project description:In our lab we detected focal genomic amplification of PDE1C in 90% of short term GBM cultures. Knocking down of PDE1C was associated with compromised capacity opf these cultures to proliferate, migrate and invade. Therefore we carried out affymetric whole genome expression analysis to identify the down stream gene effectors of this function effects.
Project description:This experiment was annotated by TAIR (http://arabidopsis.org). This experiment looks at changes in gene expression in Col-0 plants grown in soil in response to low temperature over time. Experimenter name = Jonathan Vogel Experimenter phone = 517-355-2299 Experimenter fax = 517-353-5174 Experimenter department = MSU-DOE Plant Research Lab Experimenter institute = Michigan State University Experimenter address = East Lansing Experimenter zip/postal_code = MI 48824 Experimenter country = USA Keywords: time_series_design
Project description:Background: In classrooms high concentrations of particulate matter PM10 were measured. It is unknown whether the hazard of indoor particles is similar to that of the better studied outdoor particles. This study therefore analyzed adverse biological effects of classroom in comparison to outdoor PM10. Methods: Samples were taken from six schools during teaching hours. Genome-wide gene expression in human bronchial BEAS-2B epithelial cells was analyzed, and regulated genes were verified by quantitative PCR. Polycyclic aromatic hydrocarbons (PAH), endotoxin, and cat allergen Fel d 1 were analyzed with standard methods. Enhancement of allergic reactivity by PM10 was confirmed with CD63 upregulation in human primary basophils. Acceleration of human blood coagulation was determined with supernatants of PM10-exposed human peripheral blood monocytes. Results: Indoor PM10 induced SERPINB2 (involved in blood coagulation) and inflammatory genes (like CXCL6, CXCL1, IL6, IL8, all p<0.001). Outdoor PM10 induced xenobiotic metabolizing enzymes (CYP1A1, CYP1B1, TIPARP, all p<0.001). The induction of inflammatory genes by indoor PM10 could be explained by endotoxin (indoor 128.5±42.2EU/mg versus outdoor 13.4±21.5EU/mg, p<0.001), the induction of CYP by outdoor PAH (indoor 8.3±4.9ng/mg versus outdoor 16.7±15.2ng/mg, p<0.01). The induction of SERPINB2 was confirmed by a more rapid human blood coagulation (p<0.05). Indoor PM10 had no effect on the allergic reactivity from human primary basophils, except in cat allergic individuals. This was explained by varying Fel d 1 concentrations in indoor PM10 (p<0.001). Conclusions: Indoor PM10, compared to outdoor PM10, was 6 times higher, had a different composition, and on an equal weight basis induced more inflammatory and allergenic reactions, and accelerated blood coagulation. Outdoor PM10 had significantly lower effects, but induced detoxifying enzymes. Therefore, preliminary interventions for the reduction of classroom PM10 seem reasonable, perhaps by intensified ventilation.
Project description:The soil ecosystem is critical for human health, affecting aspects of the environment from key agricultural and edaphic parameters to critical influence on climate change. Soil has more unknown biodiversity than any other ecosystem. We have applied diverse DNA extraction methods coupled with high throughput pyrosequencing to explore 4.88 × 10(9) bp of metagenomic sequence data from the longest continually studied soil environment (Park Grass experiment at Rothamsted Research in the UK). Results emphasize important DNA extraction biases and unexpectedly low seasonal and vertical soil metagenomic functional class variations. Clustering-based subsystems and carbohydrate metabolism had the largest quantity of annotated reads assigned although <50% of reads were assigned at an E value cutoff of 10(-5). In addition, with the more detailed subsystems, cAMP signaling in bacteria (3.24±0.27% of the annotated reads) and the Ton and Tol transport systems (1.69±0.11%) were relatively highly represented. The most highly represented genome from the database was that for a Bradyrhizobium species. The metagenomic variance created by integrating natural and methodological fluctuations represents a global picture of the Rothamsted soil metagenome that can be used for specific questions and future inter-environmental metagenomic comparisons. However, only 1% of annotated sequences correspond to already sequenced genomes at 96% similarity and E values of <10(-5), thus, considerable genomic reconstructions efforts still have to be performed.