1.11.1.20 thioredoxin + (5Z,9alpha,11alpha,13E,15S)-9,11-epidioxy-15-hydroxy-prosta-5,13-dienoate = thioredoxin disulfide + (5Z,9alpha,11alpha,13E,15S)-9,11,15-trihydroxyprosta-5,13-dienoate - -