[Development of Antibiotics Using Silkworm Bacteria and Fungi Infection Model]

Area of Science:

• Microbiology
• Pharmacology
• Drug Discovery

Background:

• Antimicrobial resistance (AMR) poses a significant global health threat.
• Developing novel, safe, and effective antibiotics is crucial to combat AMR.
• Traditional drug development faces challenges in identifying promising therapeutic compounds.

Purpose of the Study:

• To evaluate the utility of the silkworm model for early-stage antibiotic development.
• To screen natural products for novel antimicrobial compounds using the silkworm model.
• To identify and characterize new antibiotics effective against resistant bacteria.

Main Methods:

• Screening of 15,000 natural product samples using the silkworm model for therapeutic efficacy.
• Pharmacokinetic parameter comparison between silkworm and mammalian models.
• In vivo efficacy testing of identified compounds in a mouse systemic infection model.
• Mechanism of action studies for novel antibiotics.

Main Results:

• The silkworm model demonstrated pharmacokinetic parameters comparable to mammals, with consistent ED50 values.
• 23 promising candidate compounds were identified from 15,000 screened samples.
• A novel antibiotic, lysocin E, targeting menaquinone on the bacterial membrane, was identified and showed potent efficacy in mice.
• Additional novel agents, nosokomycin (GPI0363) and VL-2397 (ASP2397), were discovered.

Conclusions:

• The silkworm model is a valuable, cost-effective, and ethically sound tool for early antibiotic discovery and development.
• Lysocin E represents a mechanistically novel class of antibiotics with significant therapeutic potential.
• The silkworm model facilitates the identification of diverse antimicrobial and antifungal agents.