FIG 2.

Interaction of DctS with DctB in the bacterial two-hybrid system (BACTH). E. coli BTH101 was cotransformed with plasmid pairs encoding the T25 fusions and T18 fusions of the proteins as indicated: T25-DctS (pMW1697), T25-DctB (pMW1705), T18-DctS (pMW1696), DctS-T18 (pMW1695), DctR-T18 (pMW1699), and T18-DctB (pMW1708). The β-galactosidase activity was determined after growth to an OD₅₇₈ of 0.5 to 0.7. The strain expressing the pair of leucine zipper proteins T25-Zip and T18-Zip was used as a positive control for two interacting cytosolic proteins. The activity of the noninteracting proteins T18-DctS plus T25-Zip (80 Miller units, dashed line) represents the background. The data are from four or more independent biological replicates. Error bars represent the standard deviations.