FIG. 1.

Genetic structure of the entire sfaCBADEFGSH operon cloned into plasmid pANN801-13 and deletion constructs used in this study. Plasmids pJMT1 to pJMT10 carry different parts of the sfa operon in either pMMB66HE (pJMT1) or pMMB66EH (pJMT2 to pJMT10), with the sfaB promoter replaced by the inducible tac promoter and rrnB terminators placed downstream of the sfa inserts. The solid boxes indicate the locations of the sfa genes. Relevant restriction sites are indicated as follows: B, BamHI; B1, BalI; C, ClaI; D, DraIII; E, EcoRI; H, HpaI; K, KpnI; S, SmaI; St, StuI; and X, XmaI. Asterisks indicate the binding sites of the oligonucleotides used as specific probes.