In enzymology, a Prostaglandin-A<sub>1</sub> ÃÂ-isomerase () is an enzyme that catalyzes the chemical reaction
Hence, this enzyme has one substrate, (13E)-(15S)-15-hydroxy-9-oxoprosta-10,13-dienoate (Prostaglandin A1 or PGA1), and one product, (13E)-(15S)-15-hydroxy-9-oxoprosta-11,13-dienoate (Prostaglandin C1).
This enzyme belongs to the family of isomerases, specifically those intramolecular oxidoreductases transposing C=C bonds. The systematic name of this enzyme class is (13E)-(15S)-15-hydroxy-9-oxoprosta-10,13-dienoate Delta10-Delta11-isomerase. This enzyme is also called prostaglandin A isomerase.