ANTIBACTERIAL ACTIVITY OF SECRETOLYTIN, A CHROMOGRANIN B-DERIVED PEPTIDE (614-626), IS CORRELATED WITH PEPTIDE STRUCTURE

Amongst the chromogranin B (CGB) derived fragments naturally generated in bovine chromaffin granules and detected in the extracellular space , we recently identified a major peptide corresponding to the 614-626 sequence of CGB. This peptide, named secretolytin, shared an interesti ng sequence homology with the lytic domain of cecropins and displayed a potent antibacterial activity. The aim of the present study was to d etermine the structural features of secretolytin necessary for this bi ological activity, Our results suggest that an alpha-helical amphipath ic structure common to secretolytin, cecropins and pig myeloid antibac terial peptide may account for the antibacterial activity.