title: Isomerization of 6-lactoyl tetrahydropterin by sepiapterin reductase.
abstract: Isomerization of 6-1'-oxo-2'-hydroxypropyl tetrahydropterin (6-lactoyl tetrahydropterin) to 6-1'-hydroxy-2'-oxopropyl tetrahydropterin has been attributed to sepiapterin reductase. The activity is N-acetylserotonin-insensitive and has a well defined pH optimum of 8.6. The product of the reaction was detected on a HPLC chromatogram by means of electrochemical oxidation at 200 mV according to Smith and Nichol (J. Biol. Chem. 261, 2725-2737 (1986]. The C2'-keto structure of the product was confirmed by 1H-NMR spectroscopy.
mesh_terms: D000429:Alcohol Oxidoreductases / Q000032:analysis*; D001708:Biopterins / Q000031:analogs & derivatives* / Q000032:analysis; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy
chemical_list: D001708:Biopterins; C041361:6-lactoyltetrahydropterin; D000429:Alcohol Oxidoreductases; C022630:sepiapterin reductase