FAD/NAD binding domain in the electron transfer subunit of dihydroorotate dehydrogenase-like proteins. Dihydroorotate dehydrogenases (DHODs) catalyze the only redox reaction in pyrimidine de novo biosynthesis. They catalyze the oxidation of (S)-dihydroorotate to orotate coupled with the reduction of NAD+. In L. lactis, DHOD B (encoded by pyrDa) is co-expressed with pyrK and both gene products are required for full activity, as well as 3 cofactors: FMN, FAD, and an [2Fe-2S] cluster.
Jiyao W et al.(2023). "The conserved domain database in 2023.",