Figure 4.

The oyster bindin fucose lectin repeat threads onto the known fucose lectin crystal structure. Dark residues are eight sites under positive selection that surround the fucose-binding groove, indicating the importance of adaptive evolution in binding fucose. Number 138 is the ninth positively selected site, which is not in the fucose binding groove. (Figure adapted from Moy et al. [2008] and reprinted, with permission, from the National Academy of Sciences © 2008.)