ArchaeaArchaeal ProteinsBacteriaGenes, ArchaealDNA, ArchaealRNA, ArchaealGenome, ArchaealCrenarchaeotaPhylogenyMethaneGene Expression Regulation, ArchaealMolecular Sequence DataHaloferax volcaniiFungiRNA, Ribosomal, 16SMethanococcusSulfolobusSoil MicrobiologyGeologic SedimentsMethanobacteriaceaeEuryarchaeotaSeawaterNitrificationMethanosarcinaWater MicrobiologySequence Analysis, DNAMethanosarcinalesEukaryotaDNA, RibosomalMethanobacteriumBiodegradation, EnvironmentalDesulfurococcaceaeHalobacterialesHaloferaxMethanosarcinaceaeSulfolobus acidocaldariusAmino Acid SequenceBacterial Physiological PhenomenaPyrococcusEscherichia coliDNA, BacterialPyrococcus abyssiAir MicrobiologyAmmoniaSulfolobus solfataricusColony Count, MicrobialEvolution, MolecularMicrobiological TechniquesChromosomes, ArchaealBacterial ProteinsBiodiversityEukaryotic CellsMethanococcalesArchaeoglobus fulgidusPyrococcus furiosusAnaerobiosisHalobacteriaceaeSequence AlignmentEcosystemBase SequenceEnvironmental MicrobiologyThermococcusMethanosarcina barkeriCulture MediaSequence Homology, Amino AcidGenome, BacterialMicrobial ConsortiaFresh WaterArchaeal VirusesGram-Positive BacteriaGenes, rRNAProkaryotic CellsGlyceryl EthersBacteria, AnaerobicAutotrophic ProcessesFermentationBioreactorsOxidation-ReductionThermoplasmaGram-Negative BacteriaSpecies SpecificityRNA, BacterialDeltaproteobacteriaProteobacteriaGene Transfer, HorizontalMetagenomeTemperatureGenes, BacterialMetagenomicsOxidoreductasesBacteriological TechniquesMicrobiologyAnti-Bacterial AgentsThermoplasmalesHaloferax mediterraneiPlanktonSewageThermoproteaceaeHalobacterium salinarumDenaturing Gradient Gel Electrophoresis