Substrate specificity of three prostaglandin dehydrogenases.
Studies on the substrate specificity, kcat/Km, and effect of inhibitors on the human placental NADP-linked 15-hydroxyprostaglandin dehydrogenase (9-ketoprostaglandin reductase) indicate that it is very similar to a human brain carbonyl reductase which also possesses 9-ketoprostaglandin reductase activity. These observations led to a comparison of three apparently homogeneous 15-hydroxyprostaglandin dehydrogenases with varying amounts of 9-ketoprostaglandin reductase activity: an NAD- and an NADP-linked enzyme from human placenta and an NADP-linked enzyme from rabbit kidney. All three enzymes are carbonyl reductases for certain non-prostaglandin compounds. The placental NAD-linked enzyme, which has no 9-ketoprostaglandin reductase activity, is the most specific of the three. Although it has carbonyl reductase activity, a comparison of the Km and kcat/Km for prostaglandin and non-prostaglandin substrates of this enzyme suggests that its most likely function is as a 15-hydroxyprostaglandin dehydrogenase. The results of similar comparisons imply that the other two enzymes may function as less specific carbonyl reductases.
D000429:Alcohol Oxidoreductases / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000201:enzymology; D005260:Female; D006801:Humans; D006911:Hydroxyprostaglandin Dehydrogenases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D007668:Kidney / Q000201:enzymology; D007700:Kinetics; D009243:NAD / Q000494:pharmacology*; D009249:NADP / Q000494:pharmacology*; D010920:Placenta / Q000201:enzymology; D011247:Pregnancy; D011817:Rabbits; D013379:Substrate Specificity
D009243:NAD; D009249:NADP; D000429:Alcohol Oxidoreductases; D006911:Hydroxyprostaglandin Dehydrogenases; C035859:15-hydroxyprostaglandin dehydrogenase; C019642:alcohol dehydrogenase (NADP+)