Lumazine synthase

Lumazine synthase (EC 2.5.1.78, 6,7-dimethyl-8-ribityllumazine synthase, 6,7-dimethyl-8-ribityllumazine synthase 2, 6,7-dimethyl-8-ribityllumazine synthase 1, lumazine synthase 2, lumazine synthase 1, type I lumazine synthase, type II lumazine synthase, RIB4, MJ0303, RibH, Pbls, MbtLS, RibH1 protein, RibH2 protein, RibH1, RibH2) is an enzyme with systematic name 5-amino-6-(D-ribitylamino)uracil butanedionetransferase. This enzyme catalyses the following chemical reaction

1-deoxy-L-glycero-tetrulose 4-phosphate + 5-amino-6-(D-ribitylamino)uracil ⇌ 6,7-dimethyl-8-(D-ribityl)lumazine + 2 H₂O + phosphate

This enzyme is involved in riboflavin biosynthesis.