Iron as a possible mediator of the oxic-to-anoxic transition in Paracoccus denitrificans.
Expression of the lacZ gene from the Fnr-regulated FF-melR promoter on a plasmid in iron-deprived Paracoccus denitrificans cells required not only a decreased oxygen tension but also supplementation with iron. The levels of beta-galactosidase and 5-aminolevulinate synthase showed comparable responses to changes in iron availability. The presence of soluble and particulate enzymes catalyzing the reduction of Fe(III) by NADH suggests a hypothesis in which the redox state of the cytoplasmic NAD-couple determines the concentration of free Fe(II) and thereby modulates the activity of a common regulator of the Fnr type.
Kucera
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Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czech Republic.
Mat'chová
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D000624:5-Aminolevulinate Synthetase / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000494:pharmacology*; D029968:Escherichia coli Proteins; D005290:Ferric Compounds / Q000378:metabolism; D005296:Ferrous Compounds / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D007501:Iron / Q000378:metabolism* / Q000494:pharmacology; D007506:Iron-Sulfur Proteins / Q000494:pharmacology*; D009243:NAD / Q000378:metabolism; D010084:Oxidation-Reduction; D010100:Oxygen / Q000494:pharmacology*; D010231:Paracoccus denitrificans / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000494:pharmacology; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C060704:FNR protein, E coli; D005290:Ferric Compounds; D005296:Ferrous Compounds; D007506:Iron-Sulfur Proteins; D014157:Transcription Factors; D009243:NAD; D007501:Iron; D000624:5-Aminolevulinate Synthetase; D001616:beta-Galactosidase; D010100:Oxygen