Dataset Information

Mineralogical control on methylotrophic methanogenesis and implications for cryptic methane cycling in marine surface sediment.

ABSTRACT: Minerals are widely proposed to protect organic carbon from degradation and thus promote the persistence of organic carbon in soils and sediments, yet a direct link between mineral adsorption and retardation of microbial remineralisation is often presumed and a mechanistic understanding of the protective preservation hypothesis is lacking. We find that methylamines, the major substrates for cryptic methane production in marine surface sediment, are strongly adsorbed by marine sediment clays, and that this adsorption significantly reduces their concentrations in the dissolved pool (up to 40.2 ± 0.2%). Moreover, the presence of clay minerals slows methane production and reduces final methane produced (up to 24.9 ± 0.3%) by a typical methylotrophic methanogen-Methanococcoides methylutens TMA-10. Near edge X-ray absorption fine structure spectroscopy shows that reversible adsorption and occlusive protection of methylamines in clay interlayers are responsible for the slow-down and reduction in methane production. Here we show that mineral-OC interactions strongly control methylotrophic methanogenesis and potentially cryptic methane cycling in marine surface sediments.

SUBMITTER: Xiao KQ

PROVIDER: S-EPMC9114137 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Mineralogical control on methylotrophic methanogenesis and implications for cryptic methane cycling in marine surface sediment.

Xiao Ke-Qing KQ Moore Oliver W OW Babakhani Peyman P Curti Lisa L Peacock Caroline L CL

Nature communications 20220517 1

Minerals are widely proposed to protect organic carbon from degradation and thus promote the persistence of organic carbon in soils and sediments, yet a direct link between mineral adsorption and retardation of microbial remineralisation is often presumed and a mechanistic understanding of the protective preservation hypothesis is lacking. We find that methylamines, the major substrates for cryptic methane production in marine surface sediment, are strongly adsorbed by marine sediment clays, and ...[more]

PMID: 35581283

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Dataset Information

Mineralogical control on methylotrophic methanogenesis and implications for cryptic methane cycling in marine surface sediment.

Publications

Mineralogical control on methylotrophic methanogenesis and implications for cryptic methane cycling in marine surface sediment.

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