Climate Resilience Engineering: Thermal Adaptations of the Nitrogenase Mo–Fe α Subunit for Sustainable Agriculture

Abstract Increasing temperatures are a concern for global agriculture because they inhibit the activity of the nitrogenase enzyme, which is crucial for N2 fixation. The study reveals how the nitrogenase Mo–Fe α subunit adapts to high temperatures by comparing thermophilic and mesophilic bacteria. The molecular dynamics simulation study of Acetivibrio thermocellus and Endomicrobium proavitum explores how specific amino acids contribute to their physicochemical shifts, such as increased aliphatic index, hydrogen bonds, secondary-structure content, and decreased RMSD and RMSF, which reflect constrained conformational dynamics that confer thermal resilience. A. thermocellus maintains a more compact, stable structure under heat stress. These structural features enable the engineering of heat-tolerant nitrogenase, boosting sustainable agriculture in warm-climate regions.