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Updated: Feb 4, 2026

Production and Visualization of Bacterial Spheroplasts and Protoplasts to Characterize Antimicrobial Peptide Localization
Published on: August 11, 2018
[Production of Antimicrobial Polypeptides by Propionibacterium freudenreichii RVS-4-irf]
Abstract:
Propionibacterium freudenreichii RVS-4-irf is a probiotic bacterium producing antimicrobial exometabolites applicable for foodstuff protection. Production of antimicrobial factors other than lowmolecular propionates was observed in media with and without trypton. A method was developed for production of the fraction of high-molecular mass exopolymers from the culture liquid. Their polypeptide nature was confirmed using proteinase K. The preparation of extracellular polypeptides from P. freudenreichii RVS-4-irf exhibited species-specific activity in suppression of fungal and bacterial growth.
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