Figure 10.

Transport cycle involving a combination of different conformations of the X-ray/cryoEM structures of eukaryotic NSS members dDAT (pink ribbon) and hSERT (blue ribbon) indicating the progression of neurotransmitter transport cycle and conformations stabilized by binding of competitive inhibitors at the primary site and non-competitive inhibition at the allosteric site. Substrate bound O_o state can undergo conformational shift to form O_occ conformation followed by Io state to establish the transport cycle. Competitive and non-competitive inhibitors lock the transporter and prevent the formation of other conformational states.