Figure 2.

Percentage of variants in the libraries that have relative specific activities above a given threshold. The wild-type sequence is defined to have a relative specific activity of 1.00. The library with the six common hydrophilic residues and alanine, 187 members, is indicated with a (□); the hydrophilic residues plus glycine library, 154 members, (○); and hydrophilic residues plus proline, 114 members, (▵).