Dataset Information

Physiology and methane productivity of Methanobacterium thermaggregans.

ABSTRACT: Accumulation of carbon dioxide (CO₂), associated with global temperature rise, and drastically decreasing fossil fuels necessitate the development of improved renewable and sustainable energy production processes. A possible route for CO₂ recycling is to employ autotrophic and hydrogenotrophic methanogens for CO₂-based biological methane (CH₄) production (CO₂-BMP). In this study, the physiology and productivity of Methanobacterium thermaggregans was investigated in fed-batch cultivation mode. It is shown that M. thermaggregans can be reproducibly adapted to high agitation speeds for an improved CH₄ productivity. Moreover, inoculum size, sulfide feeding, pH, and temperature were optimized. Optimization of growth and CH₄ productivity revealed that M. thermaggregans is a slightly alkaliphilic and thermophilic methanogen. Hitherto, it was only possible to grow seven autotrophic, hydrogenotrophic methanogenic strains in fed-batch cultivation mode. Here, we show that after a series of optimization and growth improvement attempts another methanogen, M. thermaggregas could be adapted to be grown in fed-batch cultivation mode to cell densities of up to 1.56 g L^-1. Moreover, the CH₄ evolution rate (MER) of M. thermaggregans was compared to Methanothermobacter marburgensis, the CO₂-BMP model organism. Under optimized cultivation conditions, a maximum MER of 96.1?±?10.9 mmol L^-1 h^-1 was obtained with M. thermaggregans-97% of the maximum MER that was obtained utilizing M. marburgensis in a reference experiment. Therefore, M. thermaggregans can be regarded as a CH₄ cell factory highly suited to be applicable for CO₂-BMP.

SUBMITTER: Mauerhofer LM

PROVIDER: S-EPMC6097776 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Physiology and methane productivity of Methanobacterium thermaggregans.

Mauerhofer Lisa-Maria LM Reischl Barbara B Schmider Tilman T Schupp Benjamin B Nagy Kinga K Pappenreiter Patricia P Zwirtmayr Sara S Schuster Bernhard B Bernacchi Sébastien S Seifert Arne H AH Paulik Christian C Rittmann Simon K-M R SKR

Applied microbiology and biotechnology 20180629 17

Accumulation of carbon dioxide (CO2), associated with global temperature rise, and drastically decreasing fossil fuels necessitate the development of improved renewable and sustainable energy production processes. A possible route for CO2 recycling is to employ autotrophic and hydrogenotrophic methanogens for CO2-based biological methane (CH4) production (CO2-BMP). In this study, the physiology and productivity of Methanobacterium thermaggre ...[more]

PMID: 29959465

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Dataset Information

Physiology and methane productivity of Methanobacterium thermaggregans.

Publications

Physiology and methane productivity of Methanobacterium thermaggregans.

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