The bacterial macrolide transporter complex is a protein complex that spans the entire cell membrane system and possesses ATP-dependent xenobiotic transport activity pumping drugs (typically antibiotics) and other toxins directly from the cytosol out of the bacterial cell. Typically, it is trimeric consisting of a inner membrane ATPase (IMP), a periplasmic membrane fusion protein (MFP) and an outer membrane factor (OMF). In E. coli, macrolide transporter complexes may consists of MacB (IMP), MacA (MFP) and TolC (OMF) or AcrB (IMP), AcrA (MFP) and TolC (OMF). Trimeric TolC is a common OMF found in many macrolide transporter complexes.