The DXP-dependent biosynthetic route requires several steps and a convergence of two branches, one producing 3-hydroxy-1-aminoacetone phosphate from erythrose 4-phosphate, while the other (single enzyme) producing deoxyxylulose 5-phosphate (DXP) from glyceraldehyde 3-phosphate (GAP) and pyruvate. The condensation product of 3-hydroxy-1-aminoacetone phosphate and deoxyxylulose 5-phosphate is pyridoxine 5'-phosphate. The condensation is catalyzed by PNP synthase, encoded by "pdxJ", which creates PNP (pyridoxine 5' phosphate). The final enzyme is PNP oxidase ("pdxH"), which catalyzes the oxidation of the 4' hydroxyl group to an aldehyde using dioxigen, resulting in hydrogen peroxide.