Figure 2.

Surface exposure does not identify functionally neutral positions in the hLPYK homotetramer. Panel A shows the surface exposure of residues located in the two allosteric binding sites and previously evaluated for functional roles ^{2, 3, 5, 27}. Panel B highlights surface exposed positions at which substitution to alanine ⁹ causes either greater than a ten-fold change in one of 5 functional parameters (magenta) or between five- and ten-fold change in one of those five parameters (green). A tetramer of hLPYK from the PDB:4IMA structure was used to create this figure ⁸.