Dataset Information

Fermentative Spirochaetes drive nutrient cycling by a subsurface microbial loop in hydrocarbon-contaminated habitats

ABSTRACT: 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.

INSTRUMENT(S): LTQ Orbitrap Elite

ORGANISM(S): Uncultured Desulfobacterium Sp. Treponema

SUBMITTER: Farnusch Kaschani

LAB HEAD: Farnusch Kaschani

PROVIDER: PXD005624 | Pride | 2018-05-17

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	ACE_0177_DeltaproteobacteriumN47.fasta	Fasta
	ACE_0177_TreponemacontaminophilusHM.fasta	Fasta
	ACE_0177_XD01.raw	Raw
	ACE_0177_XD02.raw	Raw
	ACE_0177_XD03.raw	Raw

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Publications

Fermentative Spirochaetes mediate necromass recycling in anoxic hydrocarbon-contaminated habitats.

Dong Xiyang X Greening Chris C Brüls Thomas T Conrad Ralf R Guo Kun K Blaskowski Svenja S Kaschani Farnusch F Kaiser Markus M Laban Nidal Abu NA Meckenstock Rainer U RU

The ISME journal 20180530 8

Spirochaetes are frequently detected in anoxic hydrocarbon- and organohalide-polluted groundwater, but their role in such ecosystems has remained unclear. To address this, we studied a sulfate-reducing, naphthalene-degrading enrichment culture, mainly comprising the sulfate reducer Desulfobacterium N47 and the rod-shaped Spirochete Rectinema cohabitans HM. Genome sequencing and proteome analysis suggested that the Spirochete is an obligate fermenter that catabolizes proteins and carbohydrates, r ...[more]

PMID: 29849169

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