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Not just an alternative nitrogenase: The Fe-nitrogenase system belongs to the NifA regulon in Rhodobacter capsulatus

ABSTRACT: The diazotrophic bacterium Rhodobacter capsulatus synthesizes a molybdenum nitrogenase and an alternative iron-only nitrogenase, enabling growth with molecular dinitrogen as sole nitrogen source. Regulation of nitrogen fixation was analyzed by proteome profiling of wild-type and mutant strains lacking the transcriptional regulators NifA, AnfA, and MopAB.

INSTRUMENT(S): Synapt MS

ORGANISM(S): Rhodobacter Capsulatus (strain Atcc Baa-309 / Nbrc 16581 / Sb1003)

SUBMITTER: Sina Schäkermann

LAB HEAD: Julia Elisabeth Bandow

PROVIDER: PXD013515 | Pride | 2019-07-19

REPOSITORIES: Pride

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NifA is the master regulator of both nitrogenase systems in Rhodobacter capsulatus.

Demtröder Lisa L Pfänder Yvonne Y Schäkermann Sina S Bandow Julia Elisabeth JE Masepohl Bernd B

MicrobiologyOpen 20190822 12

Rhodobacter capsulatus fixes atmospheric nitrogen (N<sub>2</sub> ) by a molybdenum (Mo)-nitrogenase and a Mo-free iron (Fe)-nitrogenase, whose production is induced or repressed by Mo, respectively. At low nanomolar Mo concentrations, both isoenzymes are synthesized and contribute to nitrogen fixation. Here we examined the regulatory interplay of the central transcriptional activators NifA and AnfA by proteome profiling. As expected from earlier studies, synthesis of the structural proteins of M ...[more]

PMID: 31441241

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