Related Experiment Video
Updated: Aug 18, 2026

Using the Overlay Assay to Qualitatively Measure Bacterial Production of and Sensitivity to Pneumococcal Bacteriocins
Published on: September 30, 2014
Bacteriocin-like substance production by Bacillus licheniformis strain P40
F Cladera-Olivera1, G R Caron, A Brandelli
1Laboratório de Bioquímica e Microbiologia Aplicada, Departamento de Ciência de Alimentos, ICTA, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brasil.
Aims:
To investigate the production of bacteriocin-like compounds by Bacillus spp. isolated from the Amazon basin.
Methods And Results:
An antimicrobial substance produced by Bacillus licheniformis strain P40 was inhibitory to a broad range of indicator strains, such as Listeria monocytogenes, Bacillus cereus and clinical isolates of Streptococcus spp. The compound was stable at 100 degrees C, but lost its activity when treated at 121 degrees C/103.5 kPa for 15 min. It was resistant to the proteolytic action of trypsin and papain but sensitive to pronase E and was stable within a wide range of pH (3-11). The substance was bactericidal and bacteriolytic to L. monocytogenes.
Conclusions:
An antibacterial peptide produced by Bacillus licheniformis was characterized, presenting a broad spectrum of activity against pathogenic and spoilage organisms.
Significance And Impact Of The Study:
The identification of a substance active against important pathogens addresses an important aspect of food safety.
Related Concept Videos
Gene Regulation in Microbial Communities: Quorum Sensing
Bacterial Phylum Actinobacteria
Microbes in the Production of Fermented Foods
Production of Antibiotics
Production of Biopesticides
Inhibitors of Gram-positive Cell Wall Synthesis

