BacteriaNitrogen FixationGram-Negative BacteriaGram-Positive BacteriaBacteria, AnaerobicNitrogen IsotopesNitrogen CompoundsNitrogen CycleNitrogen DioxideBlood Urea NitrogenBacterial ProteinsMolecular Sequence DataRNA, Ribosomal, 16SDNA, BacterialBacteria, AerobicPhylogenyReactive Nitrogen SpeciesEscherichia coliDNA, RibosomalSequence Analysis, DNASymbiosisWater MicrobiologySoil MicrobiologyGene Expression Regulation, BacterialNitrogen OxidesAmmoniaCarbonGenes, BacterialPII Nitrogen Regulatory ProteinsCulture MediaNitratesBacterial Physiological PhenomenaGram-Negative Aerobic BacteriaSeawaterGram-Negative Anaerobic BacteriaAnti-Bacterial AgentsRNA, BacterialAnaerobiosisFertilizersQuaternary Ammonium CompoundsColony Count, MicrobialBiodegradation, EnvironmentalAmino Acid SequenceSulfur-Reducing BacteriaBase SequenceGenome, BacterialFermentationSpecies SpecificityGenes, rRNAPseudomonasFresh WaterBase CompositionSoilOxidation-ReductionGlutamate-Ammonia LigaseAmino AcidsAerobiosisGeologic SedimentsEnterobacteriaceaeBacterial AdhesionHydrogen-Ion ConcentrationMutationGammaproteobacteriaPlant RootsProteobacteriaBiomassNitrogenaseBacteriological TechniquesUreaEcosystemTemperatureFecesBiofilmsMicrobial Sensitivity TestsCloning, MolecularPseudomonas aeruginosaBacteroidesBetaproteobacteriaBacterial InfectionsSulfurBacterial Typing TechniquesNitrogen Mustard CompoundsPlasmidsArchaeaFungiMicrobial ViabilityRumenOxidoreductasesStaphylococcus aureusPlant LeavesRhizobiumBacillusSequence Homology, Amino AcidNitritesFatty AcidsVirulenceStreptococcusVibrioAcetylenePolymerase Chain Reaction