Represses expression from the ttgABC operon promoter and its own expression. Binds to a promoter region between the divergently transcribed ttgR and ttgABC genes/operons; in the presence of chloramphenicol or tetracycline this binding no longer occurs and ttgR and ttgABC are derepressed. This suggests that TtgR binds these antibiotics. Homodimer. Induced 4- to 8-fold in the presence of toluene; this is controlled by TtgX, a possible efflux pump global regulator. Induced by chloramphenicol and probably by tetracycline.