FIG. 7.

E. coli two-hybrid system assay showing protein-protein interaction between HlyB and HlyA. E. coli reporter strain (Stratagene, La Jolla, CA) cotransformed with pBT-HlyB (bait) and pTRG-HlyA (prey) constructs were grown on (A) nonselective plate and (B) dual-selective plate. Self-activation controls are E. coli two-hybrid system reporter strain carrying the following constructs: control 1, empty “bait” (pBT alone) cotransformed with loaded “prey” (pTRG/HlyA); control 2, loaded “bait” (pBT/HlyB) cotransformed with empty “prey” (pTRG alone). See Materials and Methods for details on the bacterial two-hybrid system assay.