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 UlaABC PTS system is involved in ascorbate transport. L-ascorbate(out) + N(pros)-phospho-L-histidyl-[protein] = L-ascorbate 6-phosphate(in) + L-histidyl-[protein] The PTS EIIB type-2 domain is phosphorylated by phospho-EIIA on a cysteinyl residue. Then, it transfers the phosphoryl group to the sugar substrate concomitantly with the sugar uptake processed by the PTS EIIC type-2 domain.