Roseoflavin is an analog of flavin mononucleotide (FMN) and riboflavin that is synthesized by the soil bacterium S. davawensis and possesses antimicrobial activity. It has been shown to bind directly to FMN riboswitch aptamers (KD = ~ 100 nM), downregulating the expression of genes responsible for the synthesis and transport of riboflavin.