Project description:Although the biodegradation of biodegradable plastics in soil and compost is well-studied, there is little knowledge on the metabolic mechanisms of synthetic polymers degradation by marine microorganisms. Here, we present a multiomics study to elucidate the biodegradation mechanism of a commercial aromatic-aliphatic copolyester film by a marine microbial enrichment culture. The plastic film and each monomer can be used as sole carbon source. Our analysis showed that the consortium synergistically degrades the polymer, different degradation steps being performed by different members of the community. Analysis of gene expression and translation profiles revealed that the relevant degradation processes in the marine consortium are closely related to poly(ethylene terephthalate) biodegradation from terrestrial microbes. Although there are multiple genes and organisms with the potential to perform a degradation step, only a few of these are active during biodegradation. Our results elucidate the potential of marine microorganisms to mineralize biodegradable plastic polymers and describe the mechanisms of labor division within the community to get maximum energetic yield from a complex synthetic substrate.
Project description:Maps of open chromatin in three primary human blood cell types of the myeloid lineage (megakaryocytes, erythroblasts and monocytes) using the formaldehyde-assisted isolation of regulatory elements method followed by next-generation sequencing (FAIRE-seq). We also generated FAIRE-seq data in the megakaryocytic cell line CHRF-288-11. In addition to our data sets, we retrieved FAIRE-seq data for the erythroblastoid cell line K562 (ENCODE Project Consortium 2012) and pancreatic islets (Gaulton et al. 2010), and reanalyzed these data sets using the same methodology.
Project description:Pseudomonas putida KT2440 is a well-known model organism for the medium chain length (mcl) PHA accumulation. (R)-Specific enoyl-coenzyme A hydratase (PhaJ) was considered to be the main supplier of monomers for PHA synthesis by converting the -oxidation intermediate, trans-2-enoyl-CoA to (R)-3-hydroxyacyl-CoA when fatty acids (FA) are used. Three PhaJ homologues, PhaJ1, PhaJ4 and MaoC are annotated in P. putida KT2440. To investigate the relationship of fatty acids - PHA metabolism and the role of each PhaJ in PHA biosynthesis in P. putida KT2440, a series of P. putida KT2440 knockouts was obtained. PHA content and monomer composition in WT and mutants under different growth conditions were analysed. However, when all three PhaJ homologues were deleted, the mutant still accumulated PHA up to 10.7 % of the cell dry weight (CDW). To identify other potential PHA monomer suppliers by analysing the proteome of the phaJ1maoCphaJ4. The deletion of (R)-3-hydroxydecanoyl-ACP:CoA transacylase (PhaG), which connects de novo FA and PHA synthesis pathways, while causing further 1.8-fold decrease in PHA content, did not abolish PHA accumulation. Further proteome analysis revealed quinoprotein alcohol dehydrogeanses PedE and PedH as potential monomer suppliers, but when these were deleted PHA level remained at 2.2 – 14.8 % CDW depending on the fatty acid used, and whether nitrogen limitation was applied. To identify the other non-specific dehydrogenases supply monomers for PHA synthesis, we analysed the proteome of the sextuple mutant under nitrogen limiting and non-limiting conditions.
Project description:Mitigation of N2O-emissions from soils is needed to reduce climate forcing by food production. Inoculating soils with N2O-reducing bacteria would be effective, but costly and impractical as a standalone operation. Here we demonstrate that digestates obtained after biogas production may provide a low-cost and widely applicable solution. Firstly, we show that indigenous N2O-reducing bacteria in digestates grow to high levels during anaerobic enrichment under N2O. Gas kinetics and meta-omic analysis show that the N2O respiring organisms, recovered as metagenome-assembled genomes (MAGs) grow by harvesting fermentation intermediates of the methanogenic consortium. Three digestate-derived denitrifying bacteria were obtained through isolation, one of which matched the recovered MAG of a dominant Dechloromonas-affiliated N2O reducer. While the identified N2O-reducers encoded genes required for a full denitrification pathway and could thus both produce and sequester N2O, their regulatory traits predicted that they act as N2O-sinks in the current system. Secondly, moving towards practical application, we show that these isolates grow by aerobic respiration in digestates, and that fertilization with these enriched digestates reduces N2O emissions. This shows that the ongoing implementation of biogas production in agriculture opens a new avenue for cheap and effective reduction of N2O emissions from food production.
Project description:These samples are being analyzed by the Duke-UNC-Texas-EBI ENCODE consortium. Expression from these cell types will compared to three whole genome open chromatin methodologies: DNaseI hypersensitivity (DNase-seq), Formaldehyde-Assisted Isolation of Regulatory elements (FAIRE-seq), and Chromatin Immunoprecipitation (ChIP-seq) . For data usage terms and conditions, please refer to http://www.genome.gov/27528022 and http://www.genome.gov/Pages/Research/ENCODE/ENCODEDataReleasePolicyFinal2008.pdf
Project description:Pseudomonas putida KT2440 is a well-known model organism for the medium chain length (mcl) PHA accumulation. (R)-Specific enoyl-coenzyme A hydratase (PhaJ) was considered to be the main supplier of monomers for PHA synthesis by converting the -oxidation intermediate, trans-2-enoyl-CoA to (R)-3-hydroxyacyl-CoA when fatty acids (FA) are used. Three PhaJ homologues, PhaJ1, PhaJ4 and MaoC are annotated in P. putida KT2440. To investigate the relationship of fatty acids - PHA metabolism and the role of each PhaJ in PHA biosynthesis in P. putida KT2440, a series of P. putida KT2440 knockouts was obtained. PHA content and monomer composition in WT and mutants under different growth conditions were analysed. However, when all three PhaJ homologues were deleted, the mutant still accumulated PHA up to 10.7 % of the cell dry weight (CDW). To identify other potential PHA monomer suppliers by analysing the proteome of the phaJ1maoCphaJ4. The proteomes of the WT, phaJ1phaJ4 and phaJ1maoCphaJ4 strains in MSM medium with octanoate under nitrogen limited condition were detected. In addition, we found that the deletion of PhaJ1 in P. putida KT2440 has a negative impact on the PHA accumulation in cells cultivated on glucose with nitrogen limitation conditions. It seems PhaJ1 also mediates the synthesis of PHA when glucose was used as the carbon and energy source. To investigate the role of PhaJ1 in PHA accumulation with glucose, the proteomes of P. putida KT2440 wild type, phaJ1, phaJ1phaJ4 and phaJ1maoCphaJ4 mutant growing on glucose were detected and compared.