Part of the ABC transporter complex GlcSTUV involved in glucose uptake (Probable). Binds glucose. Can also bind galactose and mannose (PubMed:10400586, PubMed:11260467). Binding of glucose is strongly inhibited by galactose and mannose. Optimum pH is 1.5. The complex is composed of two ATP-binding proteins (GlcV), two transmembrane proteins (GlcT and GlcU) and a solute-binding protein (GlcS). Belongs to the bacterial solute-binding protein 1 family.