Pyridoxal 5' phosphate synthase (glutamine hydrolyzing)

Pyridoxal 5'-phosphate synthase (glutamine hydrolyzing) (EC 4.3.3.6, PdxST) is an enzyme with systematic name D-ribose 5-phosphate,D-glyceraldehyde 3-phosphate pyridoxal 5'-phosphate-lyase. This enzyme catalyses the following chemical reaction

D-ribose 5-phosphate + D-glyceraldehyde 3-phosphate + L-glutamine ⇌ pyridoxal 5'-phosphate + L-glutamate + 3 H₂O + phosphate (overall reaction) (1a) L-glutamine + H₂O ⇌ L-glutamate + NH₃ (1b) D-ribose 5-phosphate + D-glyceraldehyde 3-phosphate + NH3 ⇌ pyridoxal 5'-phosphate + 4 H₂O + phosphate

The enzyme can also use ribulose 5-phosphate and dihydroxyacetone phosphate.