Reducing greenhouse gases is a significant responsibility, and scientists have found a "super-mini helper" in nature! Recent research has discovered a special type of methane-oxidizing bacteria that can more efficiently break down methane, the second most potent greenhouse gas after carbon dioxide. While researchers have high hopes for this bacteria, it's still in the laboratory stage, and scaling it up remains a major challenge.
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It can also work in low concentration methane environment
Methane is the second-largest contributor to global warming, second only to carbon dioxide. Its global warming potential is 84 times greater than that of carbon dioxide over a 20-year period. Methane is produced by human activities, including oil and gas production, industry, agriculture, and landfills.
Methane-oxidizing bacteria (methanotrophs) are not new, but they are quite demanding. Most thrive only in methane concentrations between 5,000 and 10,000 ppm. However, atmospheric methane concentrations are approximately 1.9 ppm. Even in areas prone to methane production, such as landfills, rice paddies, and oil wells, concentrations are only around 500 ppm. This makes it impractical to rely on standard methanotrophs to reduce methane.
But a team from the University of Washington and the U.S. Navy Academy has found a new possibility. They discovered a methanotrophic bacterium that can function even at low methane concentrations. The study was published in the journal Proceedings of the National Academy of Sciences (PNAS) on August 21.
The team tested six strains of methanotrophic bacteria. Among them, the strain Methylotuvimicrobium buryatense 5GB1C performed particularly well. According to Chemical & Engineering News, this strain can rapidly consume methane even at concentrations of 200 to 1000 ppm.
PHYS points out that 5GB1C can not only consume methane at low concentrations, but also continuously increase its own number. It consumes methane faster than other bacteria.
5GB1C has another benefit. One of the authors, Mary E. Lidstrom, a microbiologist and chemical engineer at the University of Washington, explained to The Guardian that boosting bacterial activity could increase nitrous oxide (N2O), the third most potent greenhouse gas, but this strain of bacteria did not produce N2O during the experiment.
There are still financial and technical barriers to scale expansion
Researchers hope the new discovery will offer new opportunities for reducing methane emissions. Lidstrom stated, "Currently, the biggest obstacle to application is technical challenges. The methane decomposition equipment must first be scaled up 20-fold. Once this is achieved, there are still issues of funding and public acceptance. We estimate that pilot testing will be possible within three to four years. Whether this can be scaled up will depend on funding and commercial viability."
According to the United Nations' 2022 Greenhouse Gas Bulletin, concentrations of carbon dioxide, methane, and nitrous oxide increased by 49%, 162%, and 24%, respectively, in 2021 compared to pre-industrial levels, with methane seeing the largest increase. Data from the World Meteorological Organization shows that methane concentrations increased by 15 ppb in 2020 and 18 ppb in 2021, respectively, the largest increases since systematic records began in 1983.
References:
*The Guardian (22 August 2023), Bacteria that ‘eat’ methane could slow global heating, study finds
*Chemical& Engineering News (27 August 2023), Methane-eating bacteria could one day slow global warming
*Clean Technicia (4 August 2023), Got Climate Change? Rescue!
*National Library of Medicine (August 21, 2023), A methanotrophic bacterium to enable methane removal for climate mitigation
*ClimateScience (January 9, 2023), Greenhouse Gases: What is Warming Up Our Earth?
*Phys.org (August 24, 2023), Researchers identify a type of bacteria that eats low volumes of methane
Source: Environmental Information Center
