From:  Expanding horizon of antimicrobial peptides: mechanistic complexity and biomedical potential

 Mammalian antimicrobial peptides.

Peptide typeSourceStructureMechanism of actionExamplesReferences
CathelicidinsHumans, other mammalsα-Helical (unstructured in solution, helical upon membrane interaction)Membrane disruption via pore formation; immunomodulation; chemoattraction of immune cellsLL-37 (human), CRAMP (mouse)[88]
α-DefensinsNeutrophils, paneth cellsβ-Sheet stabilized by disulfide bondsMembrane permeabilization; inhibition of bacterial and viral entryHNP-1, HNP-2 (humans)[89]
β-DefensinsEpithelial cellsβ-Sheet stabilized by disulfide bondsMembrane disruption; immunomodulatory effects; chemoattraction of immune cellshBD-1, hBD-2, hBD-3[90]
θ-DefensinsSome primates (e.g., rhesus macaque)Cyclic β-sheet peptidesMembrane disruption; inhibition of viral replication; high stabilityRTD-1, RTD-2[91]
LactoferricinMilk, neutrophilsAmphipathic α-helixMembrane permeabilization; iron sequestration; anti-inflammatory effectsHuman lactoferricin (hLFcin)[92]
ProtegrinsPigs (porcine)β-Hairpin stabilized by disulfide bondsMembrane disruption; bacterial lysisPG-1, PG-2[93]
HepcidinLiverCysteine-rich, β-sheetBinds iron and disrupts bacterial iron homeostasis; membrane targetingHuman hepcidin[94]