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Nitrogenase from nifV mutants of Klebsiella pneumoniae contains an altered form of the iron-molybdenum cofactor.

ABSTRACT: When the iron-molybdenum cofactor (FeMoco) was extracted from the MoFe protein of nitrogenase from a nifV mutant of Klebsiella pneumoniae and combined with the FeMoco-deficient MoFe protein from a nifB mutant, the resultant MoFe protein exhibited the NifV phenotype, i.e. in combination with wild-type Fe protein it exhibited poor N2-fixation activity and its H2-evolution activity was inhibited by CO. These data provide strong evidence that FeMoco contains the active site of nitrogenase. The metal contents and e.p.r. properties of FeMoco from wild-type and nifV mutants of K. pneumoniae are very similar.

SUBMITTER: Hawkes TR

PROVIDER: S-EPMC1153212 | biostudies-other | 1984 Jan

REPOSITORIES: biostudies-other

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Iron K-edge X-ray absorption spectroscopy of the iron-molybdenum cofactor of nitrogenase from Klebsiella pneumoniae.

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