Iron-Sulfur ProteinsElectron Transport Complex IIINitrogenaseAzotobacterOxidoreductasesSulfurIronMolybdoferredoxinGlutaredoxinsAcetyleneNitrogen FixationAzotobacter vinelandiiIron Chelating AgentsOxidation-ReductionMolybdenumSulfur CompoundsElectron Spin Resonance SpectroscopyMolecular Sequence DataDinitrogenase ReductaseAmino Acid SequenceKlebsiella pneumoniaeIron OverloadIron, DietarySulfur DioxideFerredoxinsRhodospirillum rubrumSulfur IsotopesMitochondriaAmino Acids, SulfurNitrogenIron CompoundsDithioniteHydrogenIron IsotopesRhodobacter capsulatusEthaneAmmoniaMetalloproteinsNonheme Iron Proteins