The inner membrane transporter component of an inducible organic solvent efflux pump. Involved in export of toluene and styrene but not of m-xylene, propylbenzene or ethylbenzene. Is not involved in antibiotic or AMP efflux. The ttgDEF operon is induced in the presence of toluene and styrene, but not m-xylene. Belongs to the resistance-nodulation-cell division (RND) (TC 2.A.6) family.