Scientists discover India’s first Methane-Eating Bacteria, potential breakthrough in tackling Climate challenges

A team of scientists from the Agharkar Research Institute (ARI) led by Monali Rahalkar, have made a groundbreaking discovery, identifying India’s first indigenous methane eating bacteria—known as methanotrophs. These natural agents, which thrive in environments where both methane and oxygen are present, were found in the rice fields and wetlands of the Western Ghats and Vetal Tekdi in Pune, India. 

The findings were recently published in the Indian Journal of Microbiology which revealed that the particular methanotroph, Methylocucumis oryzae, was first cultured by the team of researchers in 2018 and from 6 years of research it has been now concluded that it appeared to be phylogenetically unique with no no strains reported or cultured from any other part of the world. 

Methane-eating cucumbers’

The scientists have named the new genus and species, Methylocucumis oryzae, ‘methane-eating cucumbers’ because of their oval and elongated appearance. It was found that when they are added to the transplanted paddy fields of the high-yielding Indrayani variety, it also increases the yield and promotes early flowering. 

One notable characteristic of this bacterium is its strict mesophilic nature, meaning it cannot thrive at temperatures above 37°C, whereas most other methanotrophs can survive even at 40°C. 

Scientists identified this new species of methanotroph as a key component in the stone quarry at Vetal Tekdi. The region is home to unique flora and fauna, and the quarry’s water harbors unique invertebrates and molluscs. 

“The bacteria form light pale pink colonies, and the genome indicates a carotenoid pathway. In recent years, this methanotroph was found to promote the growth of rice plants by inducing early flowering and increasing grain yield,” Rahalkar, lead researcher of the study, was quoted as saying by TOI. 

Important for climate change 

Methane, the second most important greenhouse gas, has 26 times more global warming potential than carbon dioxide. It is produced by methanogens in wetlands, rice fields, ruminants, landfills and its mitigation is being globally regarded as utmost crucial in the fight against climate change. 

The recent discovery is being regarded as crucial by Indian experts as it can help tackle methane emissions and hence climate challenges. “While the world is experiencing global warming and climate change, there are some diligent micro-organisms in this world, doing their job perfectly in mitigating the ill effects of it,” Rahalkar was quoted as saying besides explaining, “Wetlands, ruminants, rice fields, and landfills produce methane by the action of methanogens. Methanotrophs or methane-oxidizing bacteria oxidise this methane and build their biomass, breathing oxygen and producing CO2 and H2O.”

However, the researchers noted that the slow growth rate of this methanotroph presents a challenge for large-scale cultivation and its application in biotechnology. The identification of this unique and possibly endemic methanotroph is vital for future research and its potential role in climate mitigation. Enhancing culture conditions and scaling up cultivation methods could improve the practical use of this organism in reducing atmospheric methane levels, the study further suggested. 

Earlier in a similar discovery, researchers from the University of Washington had stated that the global average temperature rise can be reduced 0.21-0.22 degree Celsius by removing 0.3-1 petagrams of methane by 2050. The experts from the 2023 study had revealed that a bacterial strain, Methylotuvimicrobium buryatense 5GB1C, if harnessed on a large scale, could prevent 240 million tonnes of methane from entering the atmosphere by 2050. 

References:

https://link.springer.com/epdf/10.1007/s12088-024-01347-x?sharing_token=p2SeHvQoROVKJlUGWENc8ve4RwlQNchNByi7wbcMAY4ZgV3JEmKkAmfM4LCwHicsJ2g56sdM32LmMTk-ei-OhEqClWVAXgYlnfCy5aH35z7iX0O3Cj_3AtwBdTuavjuTjGqGRyvgAqjkVuBF9c6WCVWlykZzFB-vGGkGQizv4Xk%3D

https://timesofindia.indiatimes.com/city/pune/scientists-find-indias-1st-methane-eating-bacteria-in-western-ghats-wetlands-vetal-tekdi-quarry/articleshow/112389676.cms

https://unece.org/challenge

https://www.downtoearth.org.in/climate-change/now-a-bacteria-that-can-eat-methane-can-it-reduce-global-warming-researchers-say-it-s-possible-91289

https://www.pnas.org/doi/10.1073/pnas.2310046120

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