Plant Antimicrobial Peptides: Structure, Function and Application Potential

Purpose: Antimicrobial peptides (AMPs) are parts of innate immunity in all domains of life, and they provide potent intrinsic defense against pathogens. Plant AMPs are noteworthy due to their low molecular weights, cysteine-stabilized structures, and thermochemical stabilities. However, characterization of plant AMPs is generally loose in the current literature. It was aimed here to present properties of plant AMPs with an unified approach to discuss and evaluate their prospective potential for to overcome antimicrobial resistance concerns. Methods: Using both national and international research as basis in this review, comperative discussion of plant AMPs with a particular focus on major families like thionines, defensins etc. was carried out by presenting their amino acid sequences, disulfide bridged stabilized tertiary structures, thermochemical stabilities, target spectrums, and molecular mechanisms. Results: Literature is presenting that plant AMPs have wide-spectrum antimicrobial activity against bacteria, fungi, viruses, and parasites. Their disulfide bridged stabilities make them resistant to environmental stress conditions. Different AMPs have different mechanisms of action compared to classical antibiotics such as membrane degradation, intracellular process alterations, and growth inhibitions. Hence, they are considered as novel antimicrobial agents that are difficult to mount resistance against. Conclusion: This study extensively presents the central role of plant AMPs in plant intrinsic defenses, and stresses the possibility of their uses in agricultural research as biopesticides and transgenic plant developments, and in medicinal research as novel antimicrobial agents. However, further in vivo studies are necessary to reveal their precise properties regarding the toxicity, stability, production efficiency to safely use them in clinical and industrial practices.