Converts 2-amino-4-deoxychorismate (ADIC) to 3-O-enolpyruvoylanthranilic acid (OPA). Involved in the biosynthesis of the benzoxazolinate moiety of the enediyne antitumor antibiotic C-1027. (2S)-2-amino-4-deoxychorismate + FMN = 3-(1-carboxyvinyloxy)anthranilate + FMNH2 Binds 1 [4Fe-4S] cluster. kcat is 15 sec(-1) for ADIC. kcat is 17 sec(-1) for FMN. Belongs to the SsuE family.