The antimicrobial effect of the broad-spectrum bacteriocin enterocin AS-48 against the toxicogenic psychrotrophic strain Bacillus cereus LWL1 has been investigated in a model food system consisting of boiled rice and in a commercial infant rice-based gruel dissolved in whole milk stored at temperatures of 37 degrees C, 15 degrees C and 6 degrees C. In food samples supplemented with enterocin AS-48 (in a concentration range of 20-35 mug/ml), viable cell counts decreased rapidly over incubation time, depending on the bacteriocin concentration, the temperature of incubation and the food sample. Enterotoxin production at 37 degrees C was also inhibited. Heat sensitivity of endospores increased markedly in food samples supplemented with enterocin AS-48: inactivation of endospores was achieved by heating for 1 min at 90 degrees C in boiled rice or at 95 degrees C in rice-based gruel. Activity of enterocin AS-48 in rice gruel was potentiated by sodium lactate in a concentration-dependent way.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.ijfoodmicro.2005.08.003 | DOI Listing |
Front Fungal Biol
December 2024
Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, United States.
The antimicrobial peptide (AMP) circularized bacteriocin enterocin AS-48 produced by sp. exhibits broad-spectrum antibacterial activity via dimer insertion into the plasma membrane to form membrane pore structures, compromising membrane integrity and leading to bactericidal activity. A specific alpha-helical region of enterocin AS-48 has been shown to be responsible for the membrane-penetrating activity of the peptide.
View Article and Find Full Text PDFInt Microbiol
May 2024
Microbiology and Immunology Department, Faculty of Pharmacy, Beni-Suef University, Beni-Suef, 62514, Egypt.
In our study, the secretome of the clinical isolate Enterococcus faecalis HY7 displayed antibacterial activity against the vancomycin-resistant Enterococcus faecalis V853. These bacteriocin-like substances showed thermal stability at a wide range of temperatures up to 121 °C, while proteinase K treatment resulted in a total loss of their activity. PCR-based screening for bacteriocin biosynthetic genes revealed that Enterococcus faecalis HY7 harbored multiple enterocin-producing genes, including ent A, avc A, and as-48.
View Article and Find Full Text PDFFront Microbiol
February 2024
Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, Netherlands.
Circular bacteriocins form a distinct group of antimicrobial peptides (AMPs) characterized by their unique head-to-tail ligated circular structure and functional properties. They belong to the ribosomally synthesized and post-translationally modified peptide (RiPP) family. The ribosomal origin of these peptides facilitates rapid diversification through mutations in the precursor genes combined with specific modification enzymes.
View Article and Find Full Text PDFChildren (Basel)
February 2024
Department of Food Technology, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, INIA-CSIC, Carretera de La Coruña Km 7, 28040 Madrid, Spain.
Enterocins are bacteriocins synthesized by strains that show an interesting antimicrobial effectiveness against foodborne pathogens such as . The objectives of this study were to identify and analyze the expression of enterocin genes of isolated from breast-fed infants and evaluate their ability to inhibit three human isolates of virulent , as well as some probiotic bacteria. The susceptibility of the strains of to fifteen antibiotics was tested, detecting their resistance to cefoxitin (constitutively resistant), oxacillin, and clindamycin.
View Article and Find Full Text PDFBMC Genomics
October 2023
Department of Microbiology, University of Granada, Avda. Fuentenueva, s/n, Granada, 18071, Spain.
Microbes live within complex communities of interacting populations, either free-living in waters and soils or symbionts of animals and plants. Their interactions include the production of antimicrobial peptides (bacteriocins) to antagonize competitors, and these producers must carry their own immunity gene for self-protection. Whether other coexisting populations are sensitive or resistant to the bacteriocin producer will be key for the population dynamics within the microbial community.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!