Fig. 6.

Dimerization of transferrin receptor protein 1 with and without high-mannose glycosylation. (A) Electrostatic potential surfaces of transferrin receptor protein 1 homodimer that bears no glycan, Man 5, or Man 9 at N727 in the minimized, equilibrated system, as calculated with the Adaptive Poisson–Boltzmann Solver (APBS). The color scale mapped on all surfaces ranges from −5 to 5 as shown in the key. Different perspectives of the dimer are depicted in Top and Bottom. Serotransferrin binding sites are outlined in each perspective. (B) Global energies of the aglycosylated, Man 5-bearing, and Man 9-bearing TFRC dimer as determined by molecular docking. (C–E) Contributions of short-range repulsive electrostatic interactions, hydrogen and disulfide bonds, and π–π stacking to the total energy of the aglycosylated and glycosylated homodimer assemblies.