TY - JOUR

T1 - Purification and characterization of a 15-ketoprostaglandin d-reductase from bovine lung

AU - Hansen, Harald S.

PY - 1979/7/27

Y1 - 1979/7/27

N2 - 15-Ketoprostaglandin d-reductase from bovine lung has been purified using affinity chromatography to apparent homogeneity, as judged from polyacrylamide gel electrophoresis with and without sodium dodecyl sulphate. Valine was identified as the N-terminal amino acid, and the isoelectric point was estimated at pH 7.8. Molecular weights of 56 000 and 39 500 were found by the use of gel filtration and SDS-polyacrylamide gel electrophoresis, respectively. The enzyme was found to be specific for the 15-keto group, thus 15-ketoprostaglandin E (apparent K = 10 µm) is a substrate, in contrast to prostaglandin E. The enzyme was active with both NADH (apparent K = 88-94 µM) and NADH (apparent K = 5-9 µM) as coenzyme, but the V max with NADH was more than twice that obtained with NADPH. The enzyme did not catalyze the reversed reaction: 13,14-dihydro-15-keto-prostaglandin E to 15-ketoprostaglandin E. The turnover number of the enzyme was determined to be either 60 or 42 min. The low value of the turnover number is compensated by a high concentration (96.4 mU/g tissue) of the enzyme in lung tissue, resulting in a high metabolic capacity. Thus, 15-ketoprostaglandin d-reductase together with 15-hydroxyprostaglandin dehydrogenase ensures an irreversible catabolism of prostaglandins.

AB - 15-Ketoprostaglandin d-reductase from bovine lung has been purified using affinity chromatography to apparent homogeneity, as judged from polyacrylamide gel electrophoresis with and without sodium dodecyl sulphate. Valine was identified as the N-terminal amino acid, and the isoelectric point was estimated at pH 7.8. Molecular weights of 56 000 and 39 500 were found by the use of gel filtration and SDS-polyacrylamide gel electrophoresis, respectively. The enzyme was found to be specific for the 15-keto group, thus 15-ketoprostaglandin E (apparent K = 10 µm) is a substrate, in contrast to prostaglandin E. The enzyme was active with both NADH (apparent K = 88-94 µM) and NADH (apparent K = 5-9 µM) as coenzyme, but the V max with NADH was more than twice that obtained with NADPH. The enzyme did not catalyze the reversed reaction: 13,14-dihydro-15-keto-prostaglandin E to 15-ketoprostaglandin E. The turnover number of the enzyme was determined to be either 60 or 42 min. The low value of the turnover number is compensated by a high concentration (96.4 mU/g tissue) of the enzyme in lung tissue, resulting in a high metabolic capacity. Thus, 15-ketoprostaglandin d-reductase together with 15-hydroxyprostaglandin dehydrogenase ensures an irreversible catabolism of prostaglandins.

UR - http://www.scopus.com/inward/record.url?scp=0018650357&partnerID=8YFLogxK

M3 - Journal article

AN - SCOPUS:0018650357

VL - 574

SP - 136

EP - 145

JO - Biochimica et Biophysica Acta - Lipids and Lipid Metabolism

JF - Biochimica et Biophysica Acta - Lipids and Lipid Metabolism

SN - 0005-2760

IS - 1

ER -