Discovery, structure, function, and applications of cyclotides: circular proteins from plants

Area of Science:

• Biochemistry
• Plant Science
• Pharmacology

Background:

• Cyclotides are plant-derived cyclic peptides characterized by a head-to-tail cyclic backbone and a cyclic cystine knot motif stabilized by three disulfide bonds.
• These peptides are found across various plant families (Violaceae, Rubiaceae, Cucurbitaceae, Fabaceae, Solanaceae) and tissues, with some species producing them in significant quantities.
• Their natural role is primarily defense against pests and pathogens.

Purpose of the Study:

• To provide an overview of cyclotide discovery, distribution in plants, and diverse applications.
• To highlight the potential of cyclotides in drug design due to their exceptional stability.
• To explore their utility as natural insecticides and protein engineering frameworks.

Main Methods:

• Literature review on cyclotide research.
• Analysis of cyclotide distribution and abundance in plant species.
• Evaluation of cyclotide properties for biotechnological applications.

Main Results:

• Cyclotides are widespread in the plant kingdom and exhibit remarkable structural stability.
• Their inherent stability makes them suitable as peptide scaffolds for therapeutic drug development.
• Significant potential exists for cyclotides as environmentally friendly insecticides and versatile protein engineering tools.

Conclusions:

• Cyclotides represent a promising class of natural products with broad applications.
• Their unique cyclic structure and stability are key features driving their use in medicine and agriculture.
• Further research into cyclotides can unlock novel solutions in drug discovery and pest management.