Figure 2.

Structural Features of griffithsin

(A) Dimerization interface of GRFT. Individual monomers are shown in blue and gray. The hinge region of the swapped strands is shown in the dashed rectangle with the glycerol molecule seen in two structures colored in cyan. The lock region is shown in the dashed oval with the relevant hydrophobic residues (L2, I101, and Y117) from both chains in stick configuration. All mutations other than the insertions at the hinge region relevant to this study are mapped onto the gray monomer. Successful and unsuccessful mutants are colored green and red, respectively, on the chain and labels. Positions that yielded mixed results are colored orange on the chain.

(B) Carbohydrate binding surface of mGRFT (1GS). The relative orientation and interaction of two symmetry related molecules (green and yellow) are shown with the C-terminal residues of one monomer in stick configuration. Hydrogen bonds that stabilize Y121 are shown in black dashed lines. Water (red sphere) and glycerol (gray) molecules in adjacent carbohydrate binding pockets are shown for the yellow molecule.