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 interesting sequence homology with the lytic domain of cecropins and displayed a potent antibacterial activity. The aim of the present study was to determine the structural features of secretolytin necessary for this biological activity. Our results suggest that an α‐helical amphipathic structure common to secretolytin, cecropins and pig myeloid antibacterial peptide may account for the antibacterial activity.