The phosphoenolpyruvate-dependent sugar phosphotransferase system (sugar PTS), a major carbohydrate active transport system, catalyzes the phosphorylation of incoming sugar substrates concomitantly with their translocation across the cell membrane. The enzyme II ManXYZ PTS system is involved in mannose transport. Homotrimer of protomers that are composed of two subunits, IIC and IID. The PTS EIIC type-4 domain forms the PTS system translocation channel and contains the specific substrate-binding site.