Interaction of various peptides with calmodulin.

In summary, we have demonstrated the existence of several endogenous substances capable of inhibiting the action of calmodulin and have identified certain structural features of a peptide that confer calmodulin inhibitory activity. These include a net positive charge, a region of hydrophobic amino acids, and the ability to form a hydrophobic alpha-helix. We believe that these properties can be used to predict the calmodulin inhibitory potency of other peptides and can also provide an insight into the structural characteristics present in calmodulin-sensitive enzymes.