Figure 7. | Thermal unfolding pathway.

Cartoon representation of the temperature-induced structural changes observed in the consensus designs. At the reference temperature the transporters are trimeric and have the substrate (sticks) bound (left panel). As temperature increases, the inter-subunit interface (cyan) between TM4 and TM2 unfolds and the subunits dissociate loosing their transport function (middle panel). Eventually, at high temperatures, the transport domains unfold and loose the ability to bind the substrate (right panel). Thick lines represent natively folded regions of the transporters, and dotted lines unfold ones.