Fig. 6: Schematic illustrating a conformational selection-fit model for sugar transport, whereby the binding of a substrate sugar stabilizes the occluded state, which can already be populated spontaneously in the absence of sugar, albeit less frequently. | Nature Structural & Molecular Biology

Fig. 6: Schematic illustrating a conformational selection-fit model for sugar transport, whereby the binding of a substrate sugar stabilizes the occluded state, which can already be populated spontaneously in the absence of sugar, albeit less frequently.

From: A two-step mechanism for sugar translocation

Fig. 6: Schematic illustrating a conformational selection-fit model for sugar transport, whereby the binding of a substrate sugar stabilizes the occluded state, which can already be populated spontaneously in the absence of sugar, albeit less frequently.

Structures representing the different states correspond to previously resolved structures: outward-open GLUT3 (PDB 5C65), outward-occluded XylE (PDB 4GC0), occluded PfHT1 (PDB 6RW3), inward-occluded XylE (PDB 4JA3) and inward-open XylE (PDB 4QIQ)9. The free-energy diagram was based on thermodynamic measurements of GLUT1 (ref. 48). out, outward; in, inward; ΔG, change in free energy. C, conformation; S, substrate; T, transition.

Back to article page