Structure and allostery in major facilitator superfamily symport mechanisms

Guan, L.

doi:10.1107/S2059798326007485

Figure 2
Sugar recognition of MelB_St, LacY and XylE, and cation recognition of MelB_St. In all panels, the N- and C-terminal helices are labeled on a blue or red background, respectively. The residues from the N- and C-terminal helices are labeled in black and red, respectively. (a) Galactoside recognition in MelB_St. The α-NPG-bound outward-facing structure at the currently highest resolution (PDB entry 9old) is used to illustrate galactoside binding. C1–C6 on the galactopyranosyl ring are labeled. Wat 1, water molecule in the sugar recognition site. (b) Na⁺ recognition in MelB_St. The Na⁺-binding pocket is shown from the inward-facing structure of WT MelB_St (PDB entry 8t60). The bound Na⁺ is shown as a red sphere. (c) Galactoside recognition in LacY. The figure was generated using the outward-facing α-NPG-bound conformation (PDB entry 4zyr). C1–C6 on the galactopyranosyl ring of α-NPG are labeled. (d) Xylose recognition in XylE. The figure was generated using the outward-facing xylose-bound conformation (PDB entry 4gby). C1–C5 on the xylofuranosyl ring are labeled. W, water molecule shown as a red sphere.

STRUCTURAL
BIOLOGY

ISSN: 2059-7983

Volume 82| Part 9| September 2026| Pages 1030-1043

https://doi.org/10.1107/S2059798326007485

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