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Title: Aerobic bacterial methane synthesis
Reports of biogenic methane (CH 4 ) synthesis associated with a range of organisms have steadily accumulated in the literature. This has not happened without controversy and in most cases the process is poorly understood at the gene and enzyme levels. In marine and freshwater environments, CH 4 supersaturation of oxic surface waters has been termed the “methane paradox” because biological CH 4 synthesis is viewed to be a strictly anaerobic process carried out by O 2 -sensitive methanogens. Interest in this phenomenon has surged within the past decade because of the importance of understanding sources and sinks of this potent greenhouse gas. In our work on Yellowstone Lake in Yellowstone National Park, we demonstrate microbiological conversion of methylamine to CH 4 and isolate and characterize an Acidovorax sp. capable of this activity. Furthermore, we identify and clone a gene critical to this process (encodes pyridoxylamine phosphate-dependent aspartate aminotransferase) and demonstrate that this property can be transferred to Escherichia coli with this gene and will occur as a purified enzyme. This previously unrecognized process sheds light on environmental cycling of CH 4 , suggesting that O 2 -insensitive, ecologically relevant aerobic CH 4 synthesis is likely of widespread distribution in the environment and should be considered in CH 4 modeling efforts.  more » « less
Award ID(s):
1817428
PAR ID:
10270641
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
118
Issue:
27
ISSN:
0027-8424
Page Range / eLocation ID:
e2019229118
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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