The lexicon of antimicrobial peptides: a complete set of arginine and tryptophan sequences

Abstract Our understanding of the activity cationic antimicrobial peptides (AMPs) has focused on well-characterized natural sequences, or limited sets synthetic designed de novo. We have undertaken a comprehensive investigation underlying primary structural features that give rise to development in AMPs. consider complete set all possible peptides, up 7 residues long, composed positively charged arginine (R) and / hydrophobic tryptophan (W), two most commonly associated with activity. found shortest active were 4 5 length, overall landscapes against gram-positive gram-negative bacteria yeast correlated. For three organisms we single peak corresponding sequences around 40% R; presence adjacent W duplets triplets also conferred greater The mechanistic basis these activities comprises combination lipid binding, particularly negatively membranes, additionally peptide aggregation, mode action previously uninvestigated for such peptides. maximum specific appeared occur 10 residues, suggesting ‘diminishing returns’ developing larger when is considered per residue peptide.