Glycosylation Shapes Isoform-Selective Recognition of Flavonoids by Human Glucose Transporters

Human glucose transporters (GLUTs) are pharmacologically relevant membrane proteins interacting with diverse flavonoids, yet previous studies focused largely on individual isoforms and limited ligand sets. Here, we docked 207 flavonoids against all 14 human GLUT isoforms, complemented by microscale thermophoresis (MST) and membrane-embedded molecular dynamics (MD) simulations. Docking revealed heterogeneous interaction profiles associated with differential glycosyl accommodation, distinguishing broad glycosylated flavonoid−preferring (gly-flav−preferring; e.g., GLUT1) and aglycone-biased (agly-flav−biased; e.g., GLUT3) groups. Glycosyl size generally outweighed attachment position, with gly-flav−preferring GLUTs tending to favor larger glycosides and agly-flav−biased GLUTs showing weaker or less favorable responses to glycosyl enlargement. Consistently, MST revealed enhanced GLUT1 binding for selected diglycosides relative to monoglycosides. MD further showed more favorable calculated binding energies for GLUT1 than GLUT3, with size predominating in GLUT1 and position contributing more prominently in GLUT3. Together, these findings highlight glycosylation as a context-dependent determinant of GLUT−flavonoid recognition.