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. This system is involved in trehalose transport at low osmolarity. alpha,alpha-trehalose(out) + N(pros)-phospho-L-histidyl-[protein] = alpha,alpha-trehalose 6-phosphate(in) + L-histidyl-[protein] At low osmolarity, treB is induced by trehalose-6-phosphate, but it becomes uninducible at high osmolarity due to induction of trehalose-6-phosphate phosphatase OstB which is part of the biosynthetic pathway of trehalose synthesis at high osmolarity. Repressed by TreR. The PTS EIIB type-1 domain is phosphorylated by phospho-EIIA-Glc (EIII-Glc) 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-1 domain. The EIIC domain type-1 forms the PTS system translocation channel and contains the specific substrate-binding site. E.coli does not possess a trehalose-specific phosphotransferase enzyme IIA component, however it seems that it use the glucose-specific phosphotransferase enzyme IIA component to delivers trehalose-6-phosphate into the cell.