Lance C. Seefeldt

Resurrected nitrogenases recapitulate canonical N-isotope biosignatures over two billion years

The paper resurrects ancient nitrogenase enzymes and shows their nitrogen isotope signatures are similar to modern ones, suggesting evolutionary invariance and supporting the use of N-isotope biosignatures for detecting life.

Structural evolution of nitrogenase enzymes over geologic time

The paper reconstructs the structural evolution of nitrogenase enzymes over 3 billion years using phylogenetics, ancestral sequence reconstruction, crystallography, and deep learning.

The Origins of ATP Dependence in Biological Nitrogen Fixation

This study experimentally reconstructs an ancestral nitrogenase enzyme and shows it strictly requires ATP hydrolysis for N2 reduction, decoupling cofactor selection from environmental availability.