Silkworms Produce Seven Classes of Antimicrobial Peptides That Fight Bacteria, Fungi, and Viruses

This is a narrative review compiling published research on antimicrobial peptides isolated from silkworms (Bombyx mori). The review covers immune responses to pathogens, AMP isolation methods, structural classification, and antimicrobial activity data against various microorganisms.

The antibiotic pipeline is drying up while resistance grows. Insect-derived AMPs represent an underexplored reservoir of potential therapeutics. Silkworms are particularly attractive because they are already mass-produced for silk, making peptide sourcing potentially scalable. The seven distinct peptide classes offer multiple starting points for drug development.

Insect immunity has evolved over hundreds of millions of years to combat diverse pathogens. The diversity of AMPs in a single insect species like the silkworm reflects this evolutionary arms race. Mining these natural peptide arsenals is a growing strategy in the search for alternatives to conventional antibiotics, and insects represent one of the largest untapped sources of bioactive peptides.

This is a review article without new experimental data. Many of the cited AMP activities were demonstrated in vitro, and clinical translation remains distant. The peptides' stability, toxicity to human cells, and pharmacokinetic properties are largely unstudied. The review does not provide quantitative comparisons of potency across the seven AMP classes.