Fig 10. Simple carrier model illustrating the transport of glucose by an alternating access mechanism.

Glucose can access the glucose binding site of PfHT from either the exofacial side or the endofacial side of the membrane but not simultaneously. N and C represent the N-terminal and C-terminal α-helical bundles of PfHT. Upon binding glucose, PfHT undergoes a series of conformational changes that allows the translocation of glucose through the central pore and its release from PfHT at the other side of the membrane. Transport is bidirectional and down the concentration gradient.