Aldo-keto reductase

Aldo/keto reductase family
File:Aldose reductase 1us0.png Ribbon diagram of human aldose reductase in complex with NADP+, citrate, and IDD594, a small molecule inhibitor. From PDB: 1us0​.
Identifiers
Symbol	Aldo_ket_red
Pfam	PF00248
InterPro	IPR001395
PROSITE	PDOC00061
SCOP	1ads
SUPERFAMILY	1ads
CDD	cd06660
Available protein structures: Pfam structures PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

The aldo-keto reductase family is a family of enzymes that includes a number of related monomeric NADPH-dependent oxidoreductases, such as aldehyde reductase, aldose reductase, prostaglandin F synthase, xylose reductase, rho crystallin, and many others.

Structure

All possess a similar structure, with a beta-alpha-beta fold characteristic of nucleotide binding proteins. The fold comprises a parallel beta-8/alpha-8-barrel, which contains a novel NADP-binding motif. The binding site is located in a large, deep, elliptical pocket in the C-terminal end of the beta sheet, the substrate being bound in an extended conformation. The hydrophobic nature of the pocket favours aromatic and apolar substrates over highly polar ones.

Binding of the NADPH coenzyme causes a massive conformational change, reorienting a loop, effectively locking the coenzyme in place. This binding is more similar to FAD- than to NAD(P)-binding oxidoreductases.

Examples

Some proteins of this family contain a potassium channel beta chain regulatory domain; these are reported to have oxidoreductase activity.

References

This article incorporates text from the public domain Pfam and InterPro IPR001395