Scientists Hack Microbes to Identify Environmental Sources of Methane - CleanTechnica

Researchers at UC Berkeley have used CRISPR gene-editing technology to manipulate a key enzyme in methane-producing microbes (methanogens) to better understand how these microbes influence the isotopic composition of methane. Methane, a potent greenhouse gas, is largely produced by microbes in oxygen-free environments such as wetlands, rice fields, landfills, and animal guts. Identifying the precise environmental sources of methane has been challenging because scientists rely on isotopic signatures—variations in the ratios of carbon and hydrogen isotopes—to trace methane origins. This study reveals that the activity of the microbial enzyme significantly affects these isotopic fingerprints, complicating efforts to accurately attribute methane emissions to specific sources. The findings suggest that current methods for quantifying methane sources may have large uncertainties, sometimes within tens of percent, limiting the ability to track changes over time or prioritize mitigation efforts effectively. By integrating molecular biology with isotope biogeochemistry, the researchers provide new insights into how methanogen biology controls methane’s isotopic signature.