Oxidoreductases;
Acting on paired donors, with incorporation or reduction of molecular oxygen;
With reduced pteridine as one donor, and incorporation of one atom of oxygen into the other donor
Requires Fe2+. The enzyme has been characterized from the bacterium Pseudomonas putida. The 4a-hydroxytetrahydropteridine formed can dehydrate to 6,7-dihydropteridine, both spontaneously and by the action of EC 4.2.1.96, 4a-hydroxytetrahydrobiopterin dehydratase. The 6,7-dihydropteridine must be enzymically reduced back to tetrahydropteridine, by EC 1.5.1.34, 6,7-dihydropteridine reductase, before it slowly rearranges into the more stable but inactive compound 7,8-dihydropteridine.
