Fosfomycin biosynthetic gene cluster and deletion plasmids used to determine the ORFs necessary to confer fosfomycin resistance on E. coli HB101. Abbreviations for restriction sites: Ba, BamHI; Bg, BglII; E, EcoRI; P, PstI; S, SphI. Arrows indicate the direction of transcription from the lac promoter of pUC118 or pUC119 with respect to the inserted fragments.