Aconitase

spinqualitylabelsall models GplT from E. coli is a Major Facilitator antiporter, rocker-switch type. We use it as example but the principle remains the same for all other Major Facilitators. Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Major Facilitators are membrane proteins that help with both influx and outflux of specific small molecules. They are neither passive channels, nor do they active pumping, like the ATPases. Like a rocker-switch, they tilt between the two states 'outside open' and 'inside open'. This tilting (or switching) is triggered when a molecule has docked inside, and it transports the molecule to the other side. We call these transporters antiporter because, when switching back, usually a second, different, molecule is transported in the opposite direction. Have a look at the complete process involving all molecules.

2ns1