Cysteine‐rich antimicrobial peptides from plants: The future of antimicrobial therapy

Abstract

There has been a spurt in the spread of microbial resistance to antibiotics due to indiscriminate use of antimicrobial agents in human medicine, agriculture, and animal husbandry. It has been realized that conventional antibiotic therapy would be less effective in the coming decades and more emphasis should be given for the development of novel antiinfective therapies. Cysteine rich peptides (CRPs) are broad‐spectrum antimicrobial agents that modulate the innate immune system of different life forms such as bacteria, protozoans, fungi, plants, insects, and animals. These are also expressed in several plant tissues in response to invasion by pathogens, and play a crucial role in the regulation of plant growth and development. The present work explores the importance of CRPs as potent antimicrobial agents, which can supplement and/or replace the conventional antibiotics. Different plant parts of diverse plant species showed the presence of antimicrobial peptides (AMPs), which had significant structural and functional diversity. The plant‐derived AMPs exhibited potent activity toward a range of plant and animal pathogens, protozoans, insects, and even against cancer cells. The cysteine‐rich AMPs have opened new avenues for the use of plants as biofactories for the production of antimicrobials and can be considered as promising antimicrobial drugs in biotherapeutics.

Antimicrobial peptides: mechanism of action, activity and clinical potential

“…AMPs also protect plants from the invasion of pathogenic microorganisms in the air and soil. 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 ].…”

On the Applicability of Chitosan Oligomers-Amino Acid Conjugate Complexes as Eco-Friendly Fungicides against Grapevine Trunk Pathogens

“…It is worth noting that plant host defense peptides (HDPs) or antimicrobial peptides (AMPs), generally cysteine-rich (nodule-specific cysteine-rich peptides, NCRs), are considered one of the main barriers developed by plants to fight infective agents [20][21][22], and are now being studied as antimicrobial agents against drug-resistant bacteria and other biomedical applications [23,24]. Amongst the different types of HDPs, the Snakin class is particularly interesting, as it encompasses the principal cysteine-rich peptides and given that the Snakin/GASA gene family has been identified in the grapevine [25].…”

Classifying Natural Products from Plants, Fungi or Bacteria using the COCONUT Database and Machine Learning

“…[27] On the other hand, our classifier also assigned a bacterial origin to two cyclic peptides (CNP0085258 and CNP0085259) [56] and a cyclotide (CNP0085363) [57] isolated from plants. Although these plants indeed contain endophytic bacteria, the plant origin of such peptides is well established, [58,59] and the SVM assignment to bacteria reflects the fact that the majority of cyclic peptides and cyclotides in the COCONUT set used for training the SVM were assigned to bacteria, compared to only a handful of cyclotides of plant origin.…”