Efagins - engineerable agents that evolved independently to target the enterococcal cell wall.

Area of Science:

• Microbiology
• Molecular Biology
• Genetics

Background:

• Enterococci are significant causes of hospital-acquired infections, often exhibiting multidrug resistance.
• The need for novel antibacterial agents against resistant enterococci is critical.

Purpose of the Study:

• To identify and characterize a new class of antibacterial inhibitors from Enterococcus faecalis.
• To investigate the mechanism of action and spectrum of activity of these novel inhibitors.

Main Methods:

• Identification and characterization of the efagin gene cluster in E. faecalis.
• Structural analysis and comparison with known phage-related elements.
• Domain-swap experiments to determine the efagin binding target.
• Testing efagin activity against a panel of E. faecalis strains with different epa genotypes and other enterococcal species.

Main Results:

• Discovery of efagins, a novel class of intrinsic E. faecalis inhibitors structurally resembling phage tails.
• Efagins target the Epa cell wall polysaccharide, with variations in efagin classes correlating with Epa genotypes.
• Efagins inhibit a broad range of E. faecalis strains and multiple enterococcal species, including vancomycin-resistant Enterococcus faecium.

Conclusions:

• Efagins represent a new class of antibacterial compounds with potential as precision antibacterials.
• The conserved efagin gene cluster and variable tail fiber region suggest co-evolution with Epa diversity.
• Efagins demonstrate significant potential for combating multidrug-resistant enterococcal infections.