Fig. 4.

ChxR activates transcription of chlamydial genes chxR, infA, tufA, CT084, and oppA. β-Galactosidase assays measured transcriptional activity from chxR–lacZ, infA–lacZ, tufA–lacZ, oppA–lacZ, and CT084–lacZ. The lacZ reporter gene was cloned downstream of each gene and expressed in an E. coli strain containing IPTG-inducible chxR on a compatible plasmid. The background activity in the presence of the vector alone is shown in the lightly shaded bars, and the activity in the presence of chxR is shown in the darker bars. The standard error of the mean is indicated by the error bars; measurements were performed in triplicate. The “control” shown was the pACYC184 vector lacking a promoter region in front of the lacZ gene.