Bis-gamma-glutamylcystine reductase () is an enzyme that catalyzes the chemical reaction
The three substrates of this enzyme are bis-ó-glutamylcystine, reduced nicotinamide adenine dinucleotide phosphate (NADPH), and a proton. Its products are ó-L-Glutamyl-L-cysteine and oxidised NADP<sup>+</sup>.
This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is gamma-glutamylcysteine:NADP+ oxidoreductase. This enzyme is also called NADPH2:bis-gamma-glutamylcysteine oxidoreductase. This enzyme participates in glutathione metabolism.