Figure 1.

The Tat two-hybrid assay. (A) A pACYC-derivative plasmid expresses the prey fusion to a reporter protein; the fusion can be either C- or N-terminal to the reporter. A compatible pBR322 replicon expresses the bait C-terminal of a Tat signal peptide. Interaction of the bait and prey allows export of the resulting complex through the twin-arginine transporter. In the periplasm, the specific activity of the reporter can be detected. (B) Map of plasmid pEMSI. pEMSI is a derivative of pBAD33 with a trc promoter and the pACYC (p15a) origin of replication. The multiple cloning site (MCS) is indicated. NcoI and EcoRI are not unique in this construct. Plasmid was used for maltose-binding protein assays.