THE REVERSE TURN AS A TEMPLATE FOR METAL COORDINATION

The structural consequence of zinc binding to three octapeptides is ex amined. The experimental results indicate that placement of a constrai ned reverse turn motif in the core of the peptide nucleates the peptid e secondary structure to facilitate metal coordination to ligands with in the remainder of the sequence. These studies demonstrate that secon dary structure in a polypeptide framework may be enhanced by a combina tion of beta-turn nucleation and metal coordination.