Biosynthesis of Riboflavin. Enzymatic Deamination of 2,5-Diamino-6-hydroxy-4-ribitylaminopyrimidine-5′-phosphate

Abstract

Cell extracts of Saccharomyces cerevisiae and Candida guilliermondii catalyze the hydrolytic deamination in position 2 of 2,5-diamino-6-hydroxy-4-ribitylaminopvrimidine 5′-phosphate. The deaminase activity is absent in rib 2 mutants of S. cerevisiae. These findings confirm the biosynthetic pathway proposed earlier on the basis of metabolic and genetic studies [2].