Dataset Information

Transient O2 pulses direct Fe crystallinity and Fe(III)-reducer gene expression within a soil microbiome.

ABSTRACT: BACKGROUND:Many environments contain redox transition zones, where transient oxygenation events can modulate anaerobic reactions that influence the cycling of iron (Fe) and carbon (C) on a global scale. In predominantly anoxic soils, this biogeochemical cycling depends on Fe mineral composition and the activity of mixed Fe(III)-reducer populations that may be altered by periodic pulses of molecular oxygen (O2). METHODS:We repeatedly exposed anoxic (4% H2:96% N2) suspensions of soil from the Luquillo Critical Zone Observatory to 1.05?×?102, 1.05?×?103, and 1.05?×?104 mmol O2 kg-1 soil h-1 during pulsed oxygenation treatments. Metatranscriptomic analysis and 57Fe Mössbauer spectroscopy were used to investigate changes in Fe(III)-reducer gene expression and Fe(III) crystallinity, respectively. RESULTS:Slow oxygenation resulted in soil Fe-(oxyhydr)oxides of higher crystallinity (38.1?±?1.1% of total Fe) compared to fast oxygenation (30.6?±?1.5%, P?

SUBMITTER: Wilmoth JL

PROVIDER: S-EPMC6199725 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Transient O<sub>2</sub> pulses direct Fe crystallinity and Fe(III)-reducer gene expression within a soil microbiome.

Wilmoth Jared Lee JL Moran Mary Ann MA Thompson Aaron A

Microbiome 20181023 1

<h4>Background</h4>Many environments contain redox transition zones, where transient oxygenation events can modulate anaerobic reactions that influence the cycling of iron (Fe) and carbon (C) on a global scale. In predominantly anoxic soils, this biogeochemical cycling depends on Fe mineral composition and the activity of mixed Fe(III)-reducer populations that may be altered by periodic pulses of molecular oxygen (O<sub>2</sub>).<h4>Methods</h4>We repeatedly exposed anoxic (4% H<sub>2</sub>:96% ...[more]

PMID: 30352628

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Dataset Information

Transient O2 pulses direct Fe crystallinity and Fe(III)-reducer gene expression within a soil microbiome.

Publications

Transient O<sub>2</sub> pulses direct Fe crystallinity and Fe(III)-reducer gene expression within a soil microbiome.

Similar Datasets

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