Amaranthus caudatus antimicrobial peptide 2 (Ac-AMP2)

Ac-AMP2 (Amaranthus caudatus antimicrobial peptide 2) is a small, basic, cysteine-rich peptide isolated from the seeds of the amaranth plant. It consists of 30 amino acids and belongs to the hevein-like family of antimicrobial peptides, characterized by a chitin-binding domain and three stabilizing disulfide bonds [1, 3, 5]. The peptide exhibits potent, broad-spectrum antifungal activity against various plant pathogens and some Gram-positive bacteria, often at concentrations significantly lower than other chitin-binding proteins [1, 4]. Its primary mechanism of action involves high-affinity, reversible binding to chitin in the fungal cell wall, which interferes with fungal growth and development [1, 5]. Ac-AMP2 is a subject of interest in biotechnology for developing transgenic crops with enhanced disease resistance and as a template for novel peptide-based antibiotics [2, 11]. However, its antimicrobial efficacy is strongly inhibited by the presence of divalent cations like calcium and potassium, which presents a challenge for its therapeutic application [1, 3]. Additionally, its structural similarity to hevein suggests a potential for allergenicity in humans [3].

Other names

AMP2 proteinAmaranthus caudatus antimicrobial peptide 26C-hevein-like peptideAc-AMP-2

Binds reversibly to chitin in fungal cell walls, inhibiting growth; also exhibits activity against Gram-positive bacteria by potentially disrupting membranes.