In enzymology, a glycine reductase is an enzyme that catalyzes the chemical reaction The 4 substrates of this enzyme are acetyl phosphate, NH3, thioredoxin disulfide, and H2O, whereas its 3 products are glycine, phosphate, and thioredoxin. This enzyme belongs to the family of oxidoreductases, to be specific, those acting on X-H and Y-H to form an X-Y bond with a disulfide as acceptor. The systematic name of this enzyme class is acetyl-phosphate ammonia:thioredoxin disulfide oxidoreductase (glycine-forming).