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. Homodimer. Induced by L-ascorbate. Repressed by UlaR. In classical PTS systems, the PTS EIIC type-2 domain forms the translocation channel and contains the specific substrate-binding site. UlaA does not exhibit the topological features of any recognized enzyme IIC. Belongs to the UlaA family. Could be the product of a pseudogene.