Project description:Contaminated aquifer (Dusseldorf-Flinger, Germany) templates extracted from 5 sediment depths ranging between 6.4 and 8.4 m below ground and over 3 years of sampling were amplified for amplicon pyrosequencing using the primers Ba27f (5’-aga gtt tga tcm tgg ctc ag-3’) and Ba519r (5’- tat tac cgc ggc kgc tg-3’), extended as amplicon fusion primers with respective primer A or B adapters, key sequence and multiplex identifiers (MID) as recommended by 454/Roche. Amplicons were purified and pooled as specified by the manufacturer. Emulsion PCR (emPCR), purification of DNA-enriched beads and sequencing run were performed following protocols and using a 2nd generation pyrosequencer (454 GS FLX Titanium, Roche) as recommended by the developer. Quality filtering of the pyrosequencing reads was performed using the automatic amplicon pipeline of the GS Run Processor (Roche), with a slight modification concerning the valley filter (vfScanAllFlows false instead of TiOnly) to extract the sequences. Demultiplexed raw reads were furhter trimmed for quality and lenght (>250 bp).
Project description:Contaminated aquifer (Dusseldorf-Flinger, Germany) templates extracted from 5 sediment depths ranging between 6.4 and 8.4 m below ground and over 3 years of sampling were amplified for amplicon pyrosequencing using the primers Ba27f (5’-aga gtt tga tcm tgg ctc ag-3’) and Ba519r (5’- tat tac cgc ggc kgc tg-3’), extended as amplicon fusion primers with respective primer A or B adapters, key sequence and multiplex identifiers (MID) as recommended by 454/Roche. Amplicons were purified and pooled as specified by the manufacturer. Emulsion PCR (emPCR), purification of DNA-enriched beads and sequencing run were performed following protocols and using a 2nd generation pyrosequencer (454 GS FLX Titanium, Roche) as recommended by the developer. Quality filtering of the pyrosequencing reads was performed using the automatic amplicon pipeline of the GS Run Processor (Roche), with a slight modification concerning the valley filter (vfScanAllFlows false instead of TiOnly) to extract the sequences. Demultiplexed raw reads were furhter trimmed for quality and lenght (>250 bp). 15 samples examined in total from important plume zones of the aquifer sampled in Feb. 2006, Sep. 2008 and Jun. 2009 (5 every year of sampling).
Project description:Purpose: Deconstructing the soil microbiome into reduced-complexity functional modules represents a novel method of microbiome analysis. The goals of this study are to confirm differences in transcriptomic patterns among five functional module consortia. Methods: mRNA profiles of 3 replicates each of functional module enrichments of soil inoculum in M9 media with either 1) xylose, 2) n-acetylglucosamine, 3) glucose and gentamycin, 4) xylan, or 5) pectin were generated by sequencing using an Illumina platform (GENEWIZ performed sequencing). Sequence reads that passed quality filters were aligned to a soil metagenome using Burrows Wheeler Aligner. Resulting SAM files were converted to raw reads using HTSeq, and annotated using Uniref90 or EGGNOG databases. Results: To reduce the size of the RNA-Seq counts table and increase its computational tractability, transcripts containing a minimum of 75 total counts, but no more than 3 zero counts, across the 15 samples were removed. The subsequent dataset was normalized using DESeq2, resulting in a dataset consisting of 6947 unique transcripts across the 15 samples, and 185,920,068 reads. We identified gene categories that were enriched in a sample type relative to the overall dataset using Fisher’s exact test. Conclusions: our dataset confirms that the functional module consortia generated from targeted enrichments of a starting soil inoculum had distinct functional trends by enrichment type.
Project description:The soil worm Enchytraeus crypticus (oligochaete) is an ecotoxicology model species although without genome or transcriptome sequence information. The present research aimed at studying, via high-throughput pyrosequencing, the transcriptome of Enchytraeus crypticus, sampled from multiple test conditions, and the construction of a high-density microarray for functional genomic studies. A pyrosequencing run retrieved approximately 1.5 million reads representing 645 million bases. After assembly, 27,296 contigs and 87,686 singletons were obtained. from which 44% and 25% were annotated as protein-coding genes. We show that the high amount of orphan genes is not due to poor sequence or assemble quality: 84% of the contig sequences contains an open reading frame with a start codon and E. crypticus homologs were identified for 92% of the core eukaryotic genes. Moreover, 65 and 77% of the unknown singletons and contigs, respectively, showed transcriptional activity. An Agilent 180K microarray platform was designed and validated by hybridizing cDNA from 3 day zinc- exposed E. crypticus to the concentration corresponding to 50% reduction in reproduction (EC50). Overall, 70% of all probes exerted a hybridization signal above background level. More specifically, the probes derived from contigs showed a wider range of average intensities when compared to probes derived from singletons. In total, 522 significantly regulated transcripts were identifying upon zinc exposure. Several significantly regulated genes exerted predicted functions (e.g. zinc efflux, zinc transport) associated with zinc stress. Unexpectedly, the microarray data suggest that zinc exposure alters retrotransposon activity in the E. crypticus genome. In conclusion, characterization of the presented E. crypticus transcriptome and associated microarray platform is a valuable and high quality resource that permits further functional genomics experiments examining gene expression patterns underlying distinct environmental stress conditions. We show that unknown sequences are not the result of technical errors but mostly represent functional genes that are actively transcribed. The data presented in our manuscript is part of a larger experiment which was performed in single, large loop design. The analysis presented here can be replicated only by including all raw data from the larger experiment (all raw files are included in the archive linked to this submission). A single channel, interwoven loop design was used to test animals exposed to zinc EC50 on reproduction as compared to untreated controls for 4 days. 4 biological replicates per condition were used containing 25 grams of soil and 5 - 7, adult old animals per replicate. T4_con stands for untreated control soil while T4_50 are the samples exposed to EC50 of zinc on reproduction.
Project description:Melon (Cucumis melo L.) is a commercially important fruit crop that is cultivated worldwide. The melon research community has recently benefited from the determination of a complete draft genome sequence and the development of associated genomic tools, which have allowed us to focus on small RNAs (sRNAs). These are short, non-coding RNAs 21â24 nucleotides in length with diverse physiological roles. In plants, they regulate gene expression and heterochromatin assembly, and control protection against virus infection. Much remains to be learned about the role of sRNAs in melon. We constructed 10 sRNA libraries from two stages of developing ovaries, fruits and photosynthetic cotyledons infected with viruses, and carried out high-throughput pyrosequencing. We catalogued and analyzed the melon sRNAs, resulting in the identification of 26 known miRNA families (many conserved with other species), the prediction of 84 melon-specific miRNA candidates, the identification of trans-acting siRNAs, and the identification of chloroplast, mitochondrion and transposon-derived sRNAs. In silico analysis revealed more than 400 potential targets for the conserved and novel miRNAs. This analysis provides insight into the composition and function of the melon small RNAome, and paves the way towards an understanding of sRNA-mediated processes that regulate melon fruit development and melonâvirus interactions. 11 small RNA libraries from several tissues of melon are included en the raw data. 2 samples from ovary, 2 samples from fruit, 1 sample from healthy cotyledons (Cultivar Tendral), 1 samples from healthy cotyledons (genotype TGR-1551), 1 sample from cotyledons (cultivar Tendral) infected with Watermelon mosaic virus (WMV), 1 sample from cotyledons (cultivar TGR-1551) infected with WMV, 1 sample from cotyledons (cultivar Tendral) infected with Melon necrotic spot virus (MNSV, Malfa5 isolate), 1 sample from cotyledons (cultivar Tendral) infected with MNSV (chimeric virus with Malfa5-264 isolates), 1 library from synthetic RNA oligos. Raw reads were obtained from two independent 454 runs, ~22,000 reads each one, to a total of 447,180 reads
Project description:Because of severe abiotic limitations, Antarctic soils represent simplified ecosystems, where microorganisms are the principle drivers of nutrient cycling. This relative simplicity makes these ecosystems particularly vulnerable to perturbations, like global warming, and the Antarctic Peninsula is among the most rapidly warming regions on the planet. However, the consequences of the ongoing warming of Antarctica on microorganisms and the processes they mediate are unknown. Here, using 16S rRNA gene pyrosequencing and qPCR, we report a number of highly consistent changes in microbial community structure and abundance across very disparate sub-Antarctic and Antarctic environments following three years of experimental field warming (+ 0.5-2°C). Specifically, we found significant increases in the abundance of fungi and bacteria and in the Alphaproteobacteria-to-Acidobacteria ratio. These alterations were linked to a significant increase in soil respiration. Furthermore, the shifts toward generalist or opportunistic bacterial communities following warming weakened the linkage between bacterial diversity and functional diversity. Warming also increased the abundance of some organisms related to the N-cycle, detected as an increase in the relative abundance of nitrogenase genes via GeoChip microarray analyses. Our results demonstrate that soil microorganisms across a range of sub-Antarctic and Antarctic environments can respond consistently and rapidly to increasing temperatures, thereby potentially disrupting soil functioning.