Simultaneous Oxidation of Atmospheric Methane, Carbon Monoxide and Hydrogen for Bacterial Growth
The second largest sink for atmospheric methane (CH 4 ) is atmospheric methane oxidizing-bacteria (atmMOB). How atmMOB are able to sustain life on the low CH 4 concentrations in air is unknown. Here, we show that during growth, with air as its only source for energy and carbon, the recently isolated...
Published in: | Microorganisms |
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Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
MDPI
2021
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Subjects: | |
Online Access: | https://hdl.handle.net/10037/20296 https://doi.org/10.3390/microorganisms9010153 |
Summary: | The second largest sink for atmospheric methane (CH 4 ) is atmospheric methane oxidizing-bacteria (atmMOB). How atmMOB are able to sustain life on the low CH 4 concentrations in air is unknown. Here, we show that during growth, with air as its only source for energy and carbon, the recently isolated atmospheric methane-oxidizer Methylocapsa gorgona MG08 (USCα) oxidizes three atmospheric energy sources: CH 4 , carbon monoxide (CO), and hydrogen (H 2 ) to support growth. The cell-specific CH 4 oxidation rate of M. gorgona MG08 was estimated at ~0.7 × 10 −18 mol cell −1 h −1 , which, together with the oxidation of CO and H 2 , supplies 0.38 kJ Cmol −1 h −1 during growth in air. This is seven times lower than previously assumed necessary to support bacterial maintenance. We conclude that atmospheric methane-oxidation is supported by a metabolic flexibility that enables the simultaneous harvest of CH 4 , H 2 and CO from air, but the key characteristic of atmospheric CH 4 oxidizing bacteria might be very low energy requirements. |
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