|PROSITE documentation PDOC00484
Eukaryotic molybdopterin oxidoreductases signature
A number of different eukaryotic oxidoreductases that require and bind a
molybdopterin cofactor have been shown  to share a few regions of sequence
similarity. These enzymes are:
- Xanthine dehydrogenase (EC 188.8.131.52), which catalyzes the oxidation of
xanthine to uric acid with the concomitant reduction of NAD. Structurally,
this enzyme of about 1300 amino acids consists of at least three distinct
domains: an N-terminal 2Fe-2S ferredoxin-like iron-sulfur binding domain
(see <PDOC00175>), a central FAD/NAD-binding domain and a C-terminal Mo-
- Aldehyde oxidase (EC 184.108.40.206), which catalyzes the oxidation aldehydes into
acids. Aldehyde oxidase is highly similar to xanthine dehydrogenase in its
sequence and domain structure.
- Nitrate reductase (EC 220.127.116.11), which catalyzes the reduction of nitrate
to nitrite. Structurally, this enzyme of about 900 amino acids consists of
an N-terminal Mo-pterin domain, a central cytochrome b5-type heme-binding
domain (see <PDOC00170>) and a C-terminal FAD/NAD-binding cytochrome
- Sulfite oxidase (EC 18.104.22.168), which catalyzes the oxidation of sulfite to
sulfate. Structurally, this enzyme of about 460 amino acids consists of an
N-terminal cytochrome b5-binding domain followed by a Mo-pterin domain.
There are a few conserved regions in the sequence of the molybdopterin-binding
domain of these enzymes. The pattern we use to detect these proteins is based
on one of them. It contains a cysteine residue which could be involved in
binding the molybdopterin cofactor.
April 2006 / Pattern revised.
PROSITE method (with tools and information) covered by this documentation:
|MOLYBDOPTERIN_EUK, PS00559; Eukaryotic molybdopterin oxidoreductases signature (PATTERN)
|Sequences in UniProtKB/Swiss-Prot known to belong to this class detected by PS00559:
||52 true positives with 12 false negatives and 4 partials.
|Other sequence(s) in UniProtKB/Swiss-Prot detected by PS00559:
||6 false positives.
|Matching PDB structures:
1FIQ 1FO4 1N5X 1V97 ... [ALL]
||Wootton J.C., Nicolson R.E., Cock J.M., Walters D.E., Burke J.F., Doyle W.A., Bray R.C.
||Enzymes depending on the pterin molybdenum cofactor: sequence families, spectroscopic properties of molybdenum and possible cofactor-binding domains.
||Biochim. Biophys. Acta 1057:157-185(1991).
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