The phosphoenolpyruvate-dependent sugar phosphotransferase system (PTS), a major carbohydrate active -transport system, catalyzes the phosphorylation of incoming sugar substrates concomitant with their translocation across the cell membrane. This system is involved in fructose transport. The EIID domain, with its homologous EIIC domain, forms the PTS system translocation channel and contains part of its specific substrate-binding site.