The reduction of small molecules, such as protons (H +), nitrate (NO3-), and nitrite (NO2-) to dihydrogen (H2) and ammonium (NH4 +) are essential reactions for life. Extant enzymes such as hydrogenase, nitrogenase, nitrate reductase, and nitrite reductase ...

Abstract. From its earliest beginnings, life’s expansion into new habitats has been profoundly shaped by its reciprocal interactions with Earth’s changing

Universal paralog protein families form due to gene duplications that occurred prior to the last universal common ancestor of life. This perspective describes how these protein families offer valuable...

Nitrogen isotope fractionation (ε15N) in sedimentary rocks has provided evidence for biological nitrogen fixation, and thus primary productivity, on the early Earth.

The study shows that nitrogenase enzymes have maintained stable isotope signatures over billions of years, revealing how ancient microbes shaped Earth’s nitrogen cycle and offering a new experimental ...

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The study shows that nitrogenase enzymes have maintained stable isotope signatures over billions of years, revealing how ancient microbes shaped Earth’s nitrogen cycle and offering a new experimental ...

The study shows that nitrogenase enzymes have maintained stable isotope signatures over billions of years, revealing how ancient microbes shaped Earth’s nitrogen cycle and offering a new experimental ...

Nitrogen isotope fractionation (ε15N) in sedimentary rocks has provided evidence for biological nitrogen fixation, and thus primary productivity, on the early Earth. However, the extent to which molecular evolution has influenced the isotopic signatures of nitrogenase, the enzyme that catalyzes the conversion of atmospheric nitrogen (N₂) to bioavailable ammonia, remains unresolved. Here, we reconstruct and experimentally characterize a library of synthetic ancestral nitrogenase genes, spanning over 2 billion years of evolutionary history. We assess the resulting ε¹⁵N values under controlled laboratory conditions. All engineered strains exhibit ε15N values within a narrow range comparable to that of modern microbes, suggesting that molybdenum (Mo)-dependent nitrogenase has been largely invariant throughout evolutionary time since the origins of this pathway. The results of this study support the early origin of molybdenum nitrogenase and the resilience of nitrogen-isotope biosignatures in ancient rocks, while also demonstrating their potential as powerful tools in the search for life beyond Earth.

The study shows that nitrogenase enzymes have maintained stable isotope signatures over billions of years, revealing how ancient microbes shaped Earth’s nitrogen cycle and offering a new experimental ...

NASA-supported scientists have resurrected an enzyme first used by organisms on Earth 3.2-billion years ago and, in the process, have validated a chemical

by Christoph — We are oc­ca­sion­al­ly warned not to com­pare ap­ples with pears (sor­ry, Eng­lish speak­ers, not with or­anges this time). Sure, both are pome fruits, and both plants be­long to t…

The study shows that nitrogenase enzymes have maintained stable isotope signatures over billions of years, revealing how ancient microbes shaped Earth’s nitrogen cycle and offering a new experimental ...

Abstract. The origin of life is one of the most compelling questions in science. While experimental prebiotic chemistry has produced a wide range of reacti