Plant Toxic Proteins: Their Biological Activities, Mechanism of Action and Removal Strategies

Abstract

Plants evolve to synthesize various natural metabolites to protect themselves against threats, such as insects, predators, microorganisms, and environmental conditions (such as temperature, pH, humidity, salt, and drought). Plant-derived toxic proteins are often secondary metabolites generated by plants. These proteins, including ribosome-inactivating proteins, lectins, protease inhibitors, α-amylase inhibitors, canatoxin-like proteins and ureases, arcelins, antimicrobial peptides, and pore-forming toxins, are found in different plant parts, such as the roots, tubers, stems, fruits, buds, and foliage. Several investigations have been conducted to explore the potential applications of these plant proteins by analyzing their toxic effects and modes of action. In biomedical applications, such as crop protection, drug development, cancer therapy, and genetic engineering, toxic plant proteins have been utilized as potentially useful instruments due to their biological activities. However, these noxious metabolites can be detrimental to human health and cause problems when consumed in high amounts. This review focuses on different plant toxic proteins, their biological activities, and their mechanisms of action. Furthermore, possible usage and removal strategies for these proteins are discussed.

α‐Amylase Inhibitors Based on Thiazolidinone Skeleton: A Promising Approach in Diabetes Management

“…The most widely accepted theories suggest that these proteins might serve as storage proteins, as controllers of endogenous α-amylases, or as protection against attacks by pests, insects, animals, or other organisms. [56] The structure, expression, inhibition specificity, and efficiency of αamylase inhibitors against digesting enzymes from a variety of sources, such as mammals, insects, and bacteria, show a considerable diversity. [57] α-Amylase inhibitors have the ability to lower endogenous α-amylase activity, which is crucial for the management of agricultural pests as well as the treatment and prevention of human disorders.…”

“…The natural defense systems of many plants include the presence of α‐amylase inhibitors. The most widely accepted theories suggest that these proteins might serve as storage proteins, as controllers of endogenous α‐amylases, or as protection against attacks by pests, insects, animals, or other organisms [56] . The structure, expression, inhibition specificity, and efficiency of α‐amylase inhibitors against digesting enzymes from a variety of sources, such as mammals, insects, and bacteria, show a considerable diversity [57] .…”

Green and environmentally friendly synthesis of silver nanoparticles with antibacterial properties from some medicinal plants

“…Plants produce secondary metabolites to protect themselves against environmental stress [ 17 ]. The use of natural products against global public health problems is prominent.…”

Antifungal Activity of Ageritin, a Ribotoxin-like Protein from Cyclocybe aegerita Edible Mushroom, against Phytopathogenic Fungi

“…: 3.2.2.22) [ 11 ]. RIPs are toxins, mainly found in plants (angiosperms) [ 12 , 13 ], able to depurinate a single adenine (A 4324 in rats) and irreversibly block protein synthesis, leading to cell death by the apoptotic pathway [ 14 , 15 , 16 ]. RIPs are likely to be involved in plant self-defense mechanisms [ 17 ], and display a variety of in vitro antimicrobial activities [ 18 ] such as antifungal, antibacterial [ 19 ] and antiviral properties [ 20 ].…”