In enzymology, a prostaglandin-E2 9-reductase (EC 1.1.1.189) is an enzyme that catalyzes the chemical reaction Thus, the two substrates of this enzyme are (5Z,13E)-(15S)-9alpha,11alpha,15-trihydroxyprosta-5,13-dienoate and NADP+, whereas its 3 products are (5Z,13E)-(15S)-11alpha,15-dihydroxy-9-oxoprosta-5,13-dienoate, NADPH, and H+.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor.
The systematic name of this enzyme class is (5Z,13E)-(15S)-9alpha,11alpha,15-trihydroxyprosta-5,13-dienoate:NADP+ 9-oxidoreductase.
This enzyme participates in arachidonic acid metabolism.
As of late 2007, 3 structures have been solved for this class of enzymes, with PDB accession codes 1Q13, 1Q5M, and 2PFG.