Part of the ABC transporter complex LpqY-SugA-SugB-SugC, which is highly specific for uptake of trehalose. Involved in the recycling of extracellular trehalose released from trehalose-containing molecules synthesized by M.tuberculosis. Trehalose uptake is essential for virulence. Probably responsible for the translocation of the substrate across the membrane. The complex is composed of two ATP-binding proteins (SugC), two transmembrane proteins (Suga and SugB) and a solute-binding protein (LpqY). Was identified as a high-confidence drug target. Belongs to the binding-protein-dependent transport system permease family.