Neurotransmitter and psychostimulant recognition by the dopamine transporter.

Epitope residues were calculated from [PDB: 4XP1, 4XP4, 4XP5, 4XP6, 4XPA, 4XPF, 4XPG and 4XPH] as the antigen residues at 4 Å atomic distance from the antibody. Only structures 4XP5 and 4XPG have contact residue H338. Structure PDB: 4XP5 lacks contact residue Y498 PDB: 4XPG lacks contact residue R502 PDB: 4XP1, 4XP6, 4XP4, 4XPF, 4XPH lack contact residue M510 PDB: 4XPH lacks contact residue R598 and PDB: 4XP6, 4XPA, 4XP5 lack contact residue D599. The epitope of 9D5 Fab on the dopamine transporter with RTI-55 bound was determined from the crystal structure of the complex, solved by molecular replacement. The Fab was used as a chaperone to aid in crystallization. The dopamine transporter construct dDAT(mfc) has deletions of residues 1-20 and 162-202, a thrombin site replacing residues 602–607 and point mutations V74A and L415A to enhance thermostability.