Nitrogen CycleNitrogen FixationNitrogen CompoundsNitrificationDenitrificationNitrogen IsotopesQuaternary Ammonium CompoundsCell CycleNitrogenPlanctomycetalesAmmoniaCrenarchaeotaArchaeaBlood Urea NitrogenNitratesNitrogen DioxideNitrite ReductasesNitritesReactive Nitrogen SpeciesSeawaterSoilBacteriaEcosystemGenes, ArchaealSoil MicrobiologyNitrous OxideOceans and SeasGeologic SedimentsDNA, ArchaealOxidation-ReductionPhylogenyNitrogen OxidesAgricultureClimate ChangePII Nitrogen Regulatory ProteinsTreesMolecular Sequence DataCarbonBiodiversityFertilizersOxidoreductasesMenstrual CycleRNA, Ribosomal, 16SGlutamate-Ammonia LigaseUreaGenome, BacterialCell Cycle ProteinsSequence Analysis, DNAAmino AcidsNitrogen Mustard CompoundsNitrogenaseSymbiosisBiomassCitric Acid CycleGlutamineEstrous CycleBacterial ProteinsPlant RootsTime FactorsPlant LeavesCulture MediaMutationGene Expression Regulation, BacterialAcetyleneDigestionKineticsBase SequenceModels, BiologicalPhosphorusPhotosynthesisGlutamate SynthaseAmino Acid SequenceAllantoinAmmonium CompoundsPoaceaeRoot Nodules, PlantAnimal FeedGenes, BacterialCyanobacteria