Figure 8. Comparison of the GLTP-Bound GSL Structures.

(A) Schematic of GSL interactions involving 24:1 GalCer in the sphingosine-out binding mode. Lettering indicates interacting GLTP amino acids, dashed arrows show hydrogen bonds oriented from donor to acceptor, the gray surface covers lipid atoms interacting with W96 indole group, the colored planes cover lipid regions participating in interchain interaction, gray lettering corresponds to interactions with a neighbor GLTP in the packing-related dimer in the crystal. The insert shows a schematic of sphingosine-sphingosine interaction of 24:1 GalCer in the crystal-related cross dimer.

(B) Schematic of GSL interactions involving 18:1 LacCer in the sphingosine-in binding mode. Lettering and colored planes are defined as in (A).