Unveiling the Function of Antimicrobial Peptides in Relation to Source and Structure.

Antimicrobial peptides (AMPs), essential components of the body's innate defense system, are expected to exert and enhance their potential antimicrobials, immunomodation and other bio-activities that combine with traditional antimicrobial agents and vaccines efficiently against multi-drug-resistant (MDR) bacteria. They are multi-source (animal, plant, microbial, etc.) and multi-functional (antimicrobial, immunomodulatory, anticancer, antiviral, antioxidant, etc.), and have been clearly categorized according to source, function, and structure in several AMP databases. However, there is insufficient evidence to support recognizing, developing, and utilizing the source-function relationship of AMPs, as their first function is usually unknown or unclear; in addition, they are usually accompanied by some shortcomings such as weak stability, high toxicity, and production cost. These have seriously hindered their development for clinical application. Therefore, it is necessary to clarify the relationship between the AMP source and function, and establish a complete system to distinguish the first function, so that more AMP candidates can enter the pipeline of new drugs as early as possible. At the same time, the key fundamental elements, scaffold and bottom logistics were proposed for the R & D pipeline of AMPs as new antimicrobial agents, including the following key points: high yielding, stability, and safety of AMPs using heterologous expression, modification, encapsulation, and coadministration toward their final successful application.