EC Explorer

4.3.3.6

pyridoxal 5′-phosphate synthase (glutamine hydrolysing)

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

PdxST

D-ribose 5-phosphate,D-glyceraldehyde 3-phosphate pyridoxal 5′-phosphate-lyase

The ammonia is provided by the glutaminase subunit and channeled to the active site of the lyase subunit by a 100 Å tunnel. The enzyme can also use ribulose 5-phosphate and dihydroxyacetone phosphate. The enzyme complex is found in aerobic bacteria, archaea, fungi and plants.

created 2011