Resurrecting Ancient Enzymes Reveals Clues to Life’s Origins and Potential for Space Exploration

Nitrogen is essential for life, yet most organisms cannot directly utilize it from the atmosphere. New research reconstructing ancient nitrogenase enzymes offers insights into how early microbes processed nitrogen billions of years ago, revealing clues about Earth’s ancient atmosphere and the evolution of life. The findings also have implications for agriculture and the potential for food production in space.

Unlocking the Secrets of Ancient Nitrogen Fixation

A team of scientists, supported by NASA’s Metal Utilization and Selection across Eons (MUSE) project, has successfully resurrected an enzyme that functioned in organisms on Earth approximately 3.2 billion years ago. This enzyme, called nitrogenase, is crucial for nitrogen fixation – the process of converting atmospheric nitrogen into a usable form for life. The research, published in Nature Communications on January 22, 2026, validates a chemical biosignature in rocks used to understand ancient life and provides a new understanding of Earth’s early biosphere.

The Importance of Nitrogenase

Nitrogenase is found in a diverse group of organisms, known as diazotrophs, including bacteria, archaea, and some eukaryotes. These organisms are capable of converting atmospheric nitrogen gas into compounds like proteins and DNA. “All living organisms need nitrogen to survive and, though it’s all around us, we can’t access it directly,” explains Utah State University biochemist Lance Seefeldt. “Enzymes called nitrogenases enable nitrogen fixation, which converts nitrogen to a form plants, animals, humans, and other life forms can access. And we’re just beginning to understand the extent to which, over the Earth’s four-billion-year history, these nitrogenases have evolved.”

Reconstructing the Past Through Synthetic Biology

The research team utilized synthetic biology techniques to analyze modern nitrogenases and reconstruct their possible ancient ancestors. USU senior scientist Derek Harris characterized a library of these synthetically reconstructed ancestral nitrogenase genes, measuring nitrogen isotope fractionation in engineered strains under controlled lab conditions. “Our role in the study was to characterize a library of the synthetically reconstructed ancestral nitrogenase genes,” says Harris.

A New Approach to Studying Early Earth

Previously, scientists relied on ancient rocks and fossils to study early life. Though, recreating ancient enzymes in the laboratory provides a new approach to understanding how these enzymes behaved in the past. According to Seefeldt, these reconstructed nitrogenases offer insights into the composition of Earth’s atmosphere and environmental conditions billions of years ago. “Until now, science has relied on ancient rock and fossils to study early life,” he says. “Our planet was vastly different billions of years ago.”

Implications for Agriculture and Space Exploration

Understanding nitrogenases, both ancient and modern, could help address current agricultural challenges, particularly in regions facing drought and fertilizer scarcity. The research may support future efforts to produce food beyond Earth. Seefeldt has collaborated on NASA-funded projects focused on growing crops in space, potentially on Mars.

The Broader Search for Life

Betül Kaçar, professor of bacteriology at the University of Wisconsin-Madison and director of the MUSE project, emphasizes the importance of understanding life’s history on Earth to inform the search for life elsewhere in the universe. “The search for life starts here at home, and our home is four billion years ancient,” she says. “So, we need to understand our own past. We need to understand life before us, if we want to understand life ahead of us and life elsewhere.”

Key Takeaways

• Nitrogenase enzymes are crucial for converting atmospheric nitrogen into a usable form for life.
• Scientists have successfully resurrected an ancient nitrogenase enzyme, providing insights into Earth’s early biosphere.
• This research validates a chemical biosignature that could be used to identify signs of ancient life on other planets.
• Understanding nitrogen fixation has implications for agriculture and space exploration.