Figure 1.
Evolution of peptide libraries for the iterative screening of cGPK binding sequences. A, B, C, and F show phosphorescence images of consecutive generations of the library screens after binding of 32P-labeled cGPK. Each library membrane carries 18 × 18 spots, which resulted from substitutions of 18 amino acids (Ser and Thr were omitted) at positions 1 and 2 in the peptides, both positions being varied in alphabetical order according to the single letter code. The best combinations are indicated with arrows. (D) Western blot of material eluted from excised sublibrary spots (red numbers in C) by using a cGPK I-specific antibody. (E) PhosphorImage of the blot shown in D.