Bacteriocin activity of enterococci from rabbits

Area of Science:

• Microbiology
• Food Science
• Animal Science

Background:

• Bacteriocins are ribosomally synthesized antimicrobial peptides with potential applications in food preservation and medicine.
• Enterococci are common inhabitants of animal gastrointestinal tracts and some strains produce bacteriocins.
• Rabbit feces can be a source of novel bacteriocin-producing microorganisms.

Purpose of the Study:

• To investigate the antimicrobial spectrum of bacteriocin-producing enterococci from rabbit feces.
• To characterize the biochemical properties, molecular mass, and structural genes of these bacteriocins.
• To evaluate the potential application of identified bacteriocins against contaminant bacteria.

Main Methods:

• Isolation and selection of enterococcal strains from rabbit feces.
• Determination of antimicrobial activity against indicator strains (e.g., Listeria innocua, Listeria monocytogenes).
• Biochemical characterization, molecular mass determination, and PCR analysis for bacteriocin structural genes (ent A, P, L50B, B).

Main Results:

• Six Enterococcus faecium strains exhibited inhibitory activity against Listeria spp., other enterococci, and staphylococci.
• Bacteriocin-like substances had molecular masses ranging from 3 to 10 kDa.
• Enterocin genes (ent A, P, L50B) were present in all tested strains, but ent B was absent. Enterococcus faecium EF2019 showed the broadest spectrum of activity.
• Partially purified bacteriocin EF2019 was thermostable, stable at various pH levels, and inhibited Listeria innocua growth effectively.

Conclusions:

• Enterococcus faecium strains isolated from rabbit feces produce bacteriocins with significant antimicrobial properties.
• Bacteriocin EF2019 demonstrates potential as a biocontrol agent against contaminant bacteria in agricultural settings, particularly rabbitries.
• Further in vitro and in vivo studies are warranted to fully explore the application of these bacteriocins.