Plant antimicrobial peptides: structures, functions, and applications

Abstract

Antimicrobial peptides (AMPs) are a class of short, usually positively charged polypeptides that exist in humans, animals, and plants. Considering the increasing number of drug-resistant pathogens, the antimicrobial activity of AMPs has attracted much attention. AMPs with broad-spectrum antimicrobial activity against many gram-positive bacteria, gram-negative bacteria, and fungi are an important defensive barrier against pathogens for many organisms. With continuing research, many other physiological functions of plant AMPs have been found in addition to their antimicrobial roles, such as regulating plant growth and development and treating many diseases with high efficacy. The potential applicability of plant AMPs in agricultural production, as food additives and disease treatments, has garnered much interest. This review focuses on the types of plant AMPs, their mechanisms of action, the parameters affecting the antimicrobial activities of AMPs, and their potential applications in agricultural production, the food industry, breeding industry, and medical field.

Antimicrobial peptides: mechanism of action, activity and clinical potential

“…There are multiple families of plants-derived AMPs, including thionins, defensins and cyclotides [ 34 ]. Thionins are widely found in seeds, stems, roots and leaves of plants [ 35 ] and have cytotoxic effects on Gram-positive bacteria [ 36 ], Gram-negative bacteria [ 36 ], yeasts [ 37 ] and other fungi [ 38 ]. Plants-derived AMPs are usually rich in cysteine residues to form multiple disulfide bonds that are important for structural stabilization [ 39 ].…”

Stapled Anoplin as an Antibacterial Agent

“…The simplest classification of AMP is based on their structure and includes linear, α-helical, antiparallel β-sheets stabilized by intramolecular disulfide bridges, combined α/β, and cyclic structures ( Huan et al, 2020 ; Li et al, 2021b ). In addition, many AMP with more complex topologies have been reported, especially among peptides from plant sources (e.g., defensins, cyclotides, thionins, knotting-type, and hevein-like peptides; Ribeiro et al, 2013 ; Koehbach and Craik, 2019 ; Li et al, 2021a ). The mechanism of AMP action mostly involves their interaction with the bacterial cell membrane and damage of the phospholipid bilayer, which causes the loss of membrane continuity.…”

A Bifunctional Synthetic Peptide With Antimicrobial and Plant Elicitation Properties That Protect Tomato Plants From Bacterial and Fungal Infections

“…Biological control appears to be an alternative or complement to the use of chemical pesticides, and several bacterial and fungal strains are commercialized as microbial biopesticides (Johnson and Temple, 2013 ; Montesinos and Bonaterra, 2017 ). Similarly, nonmicrobial biopesticides offer great possibilities for a sustainable disease management, and antimicrobial peptides (AMPs) have been proposed as novel pesticides to overcome problems due to fungal and bacterial plant pathogens (Montesinos et al, 2012 ; Zeitler et al, 2013 ; Datta et al, 2015 ; Badosa et al, 2017 ; Li et al, 2021 ). In addition, the conventional management of plant bacterial and fungal diseases has been based on targeting directly plant pathogens, but considerable efforts are oriented to identify compounds that activate the immune system of the plant (Tripathi and Dubey, 2004 ; Reignault and Walters, 2007 ; Thakur and Sohal, 2013 ; Abdul Malik et al, 2020 ).…”