Antimicrobial peptide (AMP)

Antimicrobial peptides (AMPs), also known as host defense peptides, are a diverse class of short, typically cationic and amphipathic molecules that serve as fundamental components of the innate immune system across all kingdoms of life [1][2]. They provide a rapid, broad-spectrum defense against bacteria, viruses, fungi, and parasites by directly disrupting microbial membranes or interfering with vital intracellular functions [3][4]. In humans, the most prominent families are the defensins and cathelicidins, which are produced by epithelial cells and phagocytes at sites of potential infection [5]. Beyond their direct microbicidal activity, AMPs act as potent immunomodulators by recruiting immune cells, promoting wound healing, and regulating the production of inflammatory cytokines [6]. While they are highly promising as next-generation therapeutics for multi-drug resistant infections, their clinical application is often limited by challenges such as susceptibility to proteolysis, potential toxicity to host tissues, and complex pharmacokinetic profiles [7].

Other names

Host defense peptideHDPCationic antimicrobial peptideDefensinCathelicidinMagaininCecropinLantibiotic

Antimicrobial peptides primarily exert their effects by targeting and disrupting the microbial cytoplasmic membrane through mechanisms such as pore formation (toroidal or barrel-stave models) or the carpet model, which leads to loss of membrane potential and cell lysis [3][4]. Additionally, some AMPs can translocate across the membrane to inhibit essential intracellular processes, including cell wall synthesis, DNA replication, RNA transcription, and protein folding [1][3].