Figure 4.

Multiple sequence alignment of representative sequences from three subfamilies of the type III antifreeze protein family, as defined in Figure 3. Invariant residues are marked with asterisks, and nearly invariant residues are marked with colons and periods. The conserved and the class-specific residues from the first ET analysis are highlighted in orange and in green, respectively. The class-specific residues from the second ET analysis are colored in violet. The residues composing the ice-binding surface of the AFP are highlighted in red, and the Arg314 residue, which interacts with substrates, is boxed.