2.A.1.1.124
The high affinity sugar:H⁺ symporter (sugar uptake) porter of 514 aas and 12 TMSs, STP10. It transports glucose, galactose and mannose, and is therefore a hexose transporter (Rottmann et al. 2016). The 2.4 Å structure with glucose bound has been solved, explaining high affinity sugar recognition (Paulsen et al. 2019). The results suggest a proton donor/acceptor pair that links sugar transport to proton translocation. It contains a Lid domain, conserved in all sugar transport proteins, that locks the mobile transmembrane domains through a disulfide bridge, and creates a protected environment which allows efficient coupling of the proton gradient to drive sugar uptake (Paulsen et al. 2019).