Project description:Members of the bacterial phylum Spirochaetes are primarily studied for their commensal and pathogenic roles in animal hosts. However, Spirochaetes are also frequently detected in anoxic hydrocarbon-contaminated environments but their ecological role in such ecosystems has so far remained unclear. Here we provide a functional trait to these frequently detected organisms with an example of a sulfate-reducing, naphthalene-degrading enrichment culture consisting of a sulfate-reducing deltaproteobacterium Desulfobacterium naphthalenivorans and a novel spirochete Rectinema cohabitans. Using a combination of genomic, proteomic, and physiological studies we show that R. cohabitans grows by fermentation of organic compounds derived from biomass from dead cells (necromass). It recycles the derived electrons in the form of H2 to the sulfate-reducing D. naphthalenivorans, thereby supporting naphthalene degradation and forming a simple microbial loop. We provide metagenomic evidence that equivalent associations between Spirochaetes and hydrocarbon-degrading microorganisms are of general importance in hydrocarbon- and organohalide-contaminated ecosystems. We propose that environmental Spirochaetes form a critical component of a microbial loop central to nutrient cycling in subsurface environments. This emphasizes the importance of necromass and H2-cycling in highly toxic contaminated subsurface habitats such as hydrocarbon-polluted aquifers.
2018-05-17 | PXD005624 | Pride
Project description:Microbial diversity on petroleum hydrocarbon contaminated soils
| PRJNA807052 | ENA
Project description:Microbial community diversity in petroleum hydrocarbon contaminated sites
Project description:Deciphering the in situ activities of microorganisms is essential for understanding the biogeochemical processes occurring in complex environments. Here we used environmental metaproteomics to obtain information about the identity and activity of subsurface microbial populations in coal-tar-contaminated groundwater. The present study reports metaproteomic data showing high representation of Candidatus Methylomirabilis oxyfera in our study site’s subsurface microbial community. In addition, eight of the nine proteins of the n-damo pathway were identified—indicating that n-damo is an active process occurring in situ in this habitat.
Project description:Deciphering the in situ activities of microorganisms is essential for understanding the biogeochemical processes occurring in complex environments. Here we used environmental metaproteomics to obtain information about the identity and activity of subsurface microbial populations in coal-tar-contaminated groundwater. The present study reports metaproteomic data showing high representation of Candidatus Methylomirabilis oxyfera in our study site’s subsurface microbial community. In addition, eight of the nine proteins of the n-damo pathway were identified—indicating that n-damo is an active process occurring in situ in this habitat.
Project description:Deciphering the in situ activities of microorganisms is essential for understanding the biogeochemical processes occurring in complex environments. Here we used environmental metaproteomics to obtain information about the identity and activity of subsurface microbial populations in coal-tar-contaminated groundwater. The present study reports metaproteomic data showing high representation of Candidatus Methylomirabilis oxyfera in our study site’s subsurface microbial community. In addition, eight of the nine proteins of the n-damo pathway were identified—indicating that n-damo is an active process occurring in situ in this habitat.
Project description:We demonstrate the feasibility of total RNA-SIP in experiments where microbes from a hydrocarbon-contaminated aquifer were studied in microcosms with 13C-labelled-toluene to understand their adaptation to the simultaneous availability of low levels of different electron acceptors. SIP successfully resolved the involvement of microaerobic vs. aerobic and anaerobic populations. Under microoxic, nitrate-amended conditions hydrocarbon degradation was actually stimulated, but transcripts of denitrification showed no signs of 13C-labelling. The expression of distinct oxygenase-based catabolic pathways for toluene degradation was clearly apparent in 13C-labelled mRNA. We discuss how these direct insights into the gene expression and adaptation mechanisms within complex degrader communities can guide more integrated approaches in monitoring and restoration of contaminated sites.
2019-11-08 | GSE140055 | GEO
Project description:Microbial 16S rRNA diversity in organoclay-amended hydrocarbon-contaminated soil
| PRJNA369284 | ENA
Project description:Fermentative Spirochaetes drive nutrient cycling by a subsurface microbial loop in hydrocarbon-contaminated habitats