Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

Electron paramagnetic resonance spectroscopy signals attributable to low-spin haem c in the oxidised protein and [4Fe-4S]1+ in the dithionite-reduced protein were identified, at low temperature, in Thiosphaera pantotropha periplasmic nitrate reductase. Spin integration of these signals as well as elemental analysis suggest a stoichiometry of 1.3-1.6 c-haem and 1 [4Fe-4S] cluster per enzyme molecule. The Em (at pH 7.4) of the [4Fe-4S]2+,1+ couple, -160 mV, means that it is unlikely to be physiologically reducible. Peptide sequences from the 90 kDa subunit indicate that the enzyme is a member of the family of molybdopterin guanine dinucleotide-binding polypeptides, the majority of which possess a putative [4Fe-4S] cluster binding sequence and thus may also bind a (low potential) iron-sulphur cluster.

Original publication

DOI

10.1016/0014-5793(94)00445-5

Type

Journal article

Journal

FEBS Lett

Publication Date

23/05/1994

Volume

345

Pages

76 - 80

Keywords

Amino Acid Sequence, Bacteria, Aerobic, Cell Membrane, Electron Spin Resonance Spectroscopy, Guanine Nucleotides, Heme, Iron-Sulfur Proteins, Molecular Sequence Data, Nitrate Reductase, Nitrate Reductases, Oxidation-Reduction, Peptide Fragments, Pterins, Sequence Analysis, Sequence Homology, Amino Acid