Screening of alpha-helical peptide ligands controlling a calcineurin-phosphatase activity.

In this paper, we describe an application of 202-membered fluorescently labeled peptide library designed to take an alpha-helix secondary structure. As a proof-of-concept experiment, a calmodulin (CaM)/calcineurin (Cn) pair was chosen to screen alpha-helical peptide ligands that tightly bind to CaM and also control enzymatic functions of Cn. Three peptides were successfully selected from the library by assaying Cn-phosphatase activities and peptide-CaM interactions (dual check process). The strategy using a designed peptide library shows real promise as a peptide-based high-throughput screening system.