Abstract
The change in fluorescence of intactAzotobacter vinelandii was observed to study the oxidation and reduction of flavin and pyridine nucleotides resulting from carbon and hydrogen metabolism. Metronidazole, acetaldehyde, and oxygen each oxidized flavin. Flavin oxidized by metronidazole or acetaldehyde was reduced by addition of mannitol or ethanol, but not by acetate or hydrogen. The fluorescence induced by oxygen was transient. Mannitol, ethanol, acetate, acetaldehyde, and hydrogen shortened the duration of the oxygen-dependent fluorescence and supported respiration. The changes in redox state of pyridine nucleotides corresponded to the changes in flavin redox state. This indicates that the use of reducing equivalents from uptake hydrogenase is limited to the respiratory electron transport system inAzotobacter vinelandii.
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Peterson, J.B., LaRue, T.A. Whole-cell fluorescence for observing reductive metabolism from carbon compounds and hydrogen inAzotobacter vinelandii . Current Microbiology 17, 209–214 (1988). https://doi.org/10.1007/BF01589454
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DOI: https://doi.org/10.1007/BF01589454