Purification and partial characterization of prostaglandin D2 11-keto reductase in rabbit liver

The cytoplasmic NADPH-dependent prostaglandin D2 11-keto reductase from rabbit liver was purified by a series of chromatographic procedures including isoelectric focusing. The enzyme catalyzed the conversion of prostaglandin D2 to prostaglandin F2 alpha and had a pH optimum of 7.0-7.5, and an isoelectric point of 5.8. The molecular weight was estimated to be 66 000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Enzymic activity was time and concentration dependent and required NADPH as cofactor.