Nitrogen FixationNitrogenaseGluconacetobacterAzotobacter vinelandiiMolybdoferredoxinSymbiosisNitrogen CycleNitrogenAcetyleneRoot Nodules, PlantRhizobiumSinorhizobium melilotiRhizobiaceaeNitrogen IsotopesGenes, BacterialFixation, OcularLotusAzotobacterMedicago sativaPlant Root NodulationPII Nitrogen Regulatory ProteinsBacterial ProteinsRhizobium leguminosarumFracture FixationRhizobium etliPlant RootsBradyrhizobiumCyanotheceLeghemoglobinGene Expression Regulation, BacterialMolecular Sequence DataKlebsiella pneumoniaeCyanobacteriaMedicago truncatulaCarbonPhaseolusAnabaenaComplement Fixation TestsTissue FixationFabaceaeQuaternary Ammonium CompoundsAmmoniaNitrogen CompoundsModels, BiologicalGlutamate-Ammonia LigaseOxidoreductasesDenitrificationBlood Urea Nitrogen