1 research outputs found
Aquatic and terrestrial cyanobacteria produce methane
Evidence is accumulating to challenge the paradigm that biogenic methanogenesis, considered a strictly anaerobic
process, is exclusive to archaea. We demonstrate that cyanobacteria living in marine, freshwater, and terrestrial
environments produce methane at substantial rates under light, dark, oxic, and anoxic conditions, linking methane
production with light-driven primary productivity in a globally relevant and ancient group of photoautotrophs.
Methane production, attributed to cyanobacteria using stable isotope labeling techniques, was enhanced during
oxygenic photosynthesis. We suggest that the formation of methane by cyanobacteria contributes to methane
accumulation in oxygen-saturated marine and limnic surface waters. In these environments, frequent cyanobacterial
blooms are predicted to further increase because of global warming potentially having a direct positive feedback
on climate change. We conclude that this newly identified source contributes to the current natural methane budget
and most likely has been producing methane since cyanobacteria first evolved on EarthPeer reviewe