Revived 3-Billion-Year-Old Nitrogenase Still Fixes Nitrogen
Researchers rebuilt four ancient nitrogenase enzymes dating up to about 2.3 billion years ago and inserted them into Azotobacter vinelandii. All variants supported nitrogen fixation, though at slower rates than modern enzymes, and produced nitrogen-isotope fingerprints that match those seen in modern microbes and Archean rocks, implying an earlier origin for Mo-nitrogenase. The work offers new ways to study Earth's early biology and could inform future agricultural and exobiology research.
