The name of this superfamily has been modified since the most recent official CATH+ release (v4_3_0). At the point of the last release, this superfamily was named:

"
Aldehyde oxidase/xanthine dehydrogenase, molybdopterin binding domain
".

Functional Families

Overview of the Structural Clusters (SC) and Functional Families within this CATH Superfamily. Clusters with a representative structure are represented by a filled circle.
« Back to all FunFams

FunFam 4: Xanthine dehydrogenase oxidase

There are 3 EC terms in this cluster

Please note: EC annotations are assigned to the full protein sequence rather than individual protein domains. Since a given protein can contain multiple domains, it is possible that some of the annotations below come from additional domains that occur in the same protein, but have been classified elsewhere in CATH.

Note: The search results have been sorted with the annotations that are found most frequently at the top of the list. The results can be filtered by typing text into the search box at the top of the table.

EC Term Annotations Evidence
Aldehyde oxidase. [EC: 1.2.3.1]
An aldehyde + H(2)O + O(2) = a carboxylate + H(2)O(2).
  • The enzyme from liver exhibits a broad substrate specificity, and is involved in the metabolism of xenobiotics, including the oxidation of N-heterocycles and aldehydes and the reduction of N-oxides, nitrosamines, hydroxamic acids, azo dyes, nitropolycyclic aromatic hydrocarbons, and sulfoxides.
  • The enzyme is also responsible for the oxidation of retinal, an activity that was initially attributed to a distinct enzyme (EC 1.2.3.11).
  • Formerly EC 1.2.3.11.
16 C4NYZ3 G3X982 H9TB17 H9TB18 H9TB19 O54754 P48034 P80456 Q06278 Q3TYQ9
(6 more...)
Xanthine dehydrogenase. [EC: 1.17.1.4]
Xanthine + NAD(+) + H(2)O = urate + NADH.
  • Acts on a variety of purines and aldehydes, including hypoxanthine.
  • The mammalian enzyme can also convert all-trans retinol to all-trans- retinoate, while the substrate is bound to a retinoid-binding protein.
  • The enzyme from eukaryotes contains [2Fe-2S], FAD and a molybdenum center.
  • The mammallian enzyme predominantly exists as the NAD-dependent dehydrogenase (EC 1.17.1.4).
  • During purification the enzyme is largely converted to an O(2)- dependent form, EC 1.17.3.2.
  • The conversion can be triggered by several mechanisms, including the oxidation of cysteine thiols to form disulfide bonds (which can be catalyzed by EC 1.8.4.7 in the presence of glutathione disulfide) or limited proteolysis, which results in irreversible conversion.
  • The conversion can also occur in vivo.
  • Formerly EC 1.2.1.37 and EC 1.1.1.204.
11 P08793 P10351 P22811 P22985 P47989 P47990 P80457 P91711 Q00519 Q54FB7
(1 more...)
Xanthine oxidase. [EC: 1.17.3.2]
Xanthine + H(2)O + O(2) = urate + H(2)O(2).
  • Also oxidizes hypoxanthine, some other purines and pterins, and aldehydes, but is distinct from EC 1.2.3.1.
  • Under some conditions the product is mainly superoxide rather than peroxide: R-H + H(2)O + 2 O(2) = ROH + 2 O(2)(.-) + 2 H(+).
  • The mammallian enzyme predominantly exists as an NAD-dependent dehydrogenase (EC 1.17.1.4).
  • During purification the enzyme is largely converted to the O(2)- dependent xanthine oxidase form (EC 1.17.3.2).
  • The conversion can be triggered by several mechanisms, including the oxidation of cysteine thiols to form disulfide bonds (which can be catalyzed by EC 1.8.4.7 in the presence of glutathione disulfide) or limited proteolysis, which results in irreversible conversion.
  • The conversion can also occur in vivo.
  • Formerly EC 1.1.3.22 and EC 1.2.3.2.
6 P22985 P47989 P47990 P80457 Q00519 Q9MYW6
CATH-Gene3D is a Global Biodata Core Resource Learn more...