Fold (b.45): Split barrel-like [50474]

Superfamily (b.45.1): FMN-binding split barrel [50475]

Family (b.45.1.1): PNP-oxidase like [50476]

Family (b.45.1.2): NADH:FMN oxidoreductase-like [50482]

Family (b.45.1.3): UbiD middle domain-like [141368]

Family (b.45.1.4): MTH863-like [159164]