“…1 Some antimicrobial substances are non-specific, such as short-chain fatty acids or hydrogen peroxide, while others are specific with a very narrow killing range, such as bacteriocins, bacteriocin-like inhibitory substances (BLIS), and bacteriophages. 5 They comprise a large and functionally diverse family of toxins found in all major lineages of Bacteria and Archaea, but there are certain features that unite them as a family; they are all ribosomally synthesized proteinaceous compounds and are active against bacteria closely related to the producing bacteria. 5 They comprise a large and functionally diverse family of toxins found in all major lineages of Bacteria and Archaea, but there are certain features that unite them as a family; they are all ribosomally synthesized proteinaceous compounds and are active against bacteria closely related to the producing bacteria.…”
The aim of this study was the partial characterization of the antimicrobial peptide bacteriocin G 2 produced by probiotic bacteria Lactobacillus plantarum G 2 , which was isolated from a clinical sample of a healthy person. Antimicrobial substance was secreted in the supernatant of an L. plantarum G 2 culture, and showed a diverse spectrum of antimicrobial activity of all the tested strains of the genera Lactobacillus and the pathogenic bacteria Staphylococcus aureus and Salmonella аbony. Isoelectric focusing revealed that bacteriocin G 2 is a cationic peptide (pI about 10) with a molecular mass of 2.2 kDa according to tricine-sodium dodecyl sulphate-polyacrylamide gel electrophoresis, SDS-PAGE. The antimicrobial activity of bacteriocin G 2 was diminished by the proteolytic action of trypsin and proteinase K. Bacteriocin G 2 preserved its biological activity in the temperature range 40-60 °C (15 min), which was lost at 80 °C. Bacteriocin G 2 was stable in the pH range 2-9, while treatment with 1 % Tween 80 and 1 % urea resulted in increased antimicrobial activity. The probiotic strain L. plantarum G 2 produces the antimicrobial substance proteinaceous in nature with bacteriocin characteristics. Bacteriocin production is one of the key properties of probiotic bacteria with clinical potential as antiinfective agents, which will increase the likelihood of its in vivo efficacy.
“…1 Some antimicrobial substances are non-specific, such as short-chain fatty acids or hydrogen peroxide, while others are specific with a very narrow killing range, such as bacteriocins, bacteriocin-like inhibitory substances (BLIS), and bacteriophages. 5 They comprise a large and functionally diverse family of toxins found in all major lineages of Bacteria and Archaea, but there are certain features that unite them as a family; they are all ribosomally synthesized proteinaceous compounds and are active against bacteria closely related to the producing bacteria. 5 They comprise a large and functionally diverse family of toxins found in all major lineages of Bacteria and Archaea, but there are certain features that unite them as a family; they are all ribosomally synthesized proteinaceous compounds and are active against bacteria closely related to the producing bacteria.…”
The aim of this study was the partial characterization of the antimicrobial peptide bacteriocin G 2 produced by probiotic bacteria Lactobacillus plantarum G 2 , which was isolated from a clinical sample of a healthy person. Antimicrobial substance was secreted in the supernatant of an L. plantarum G 2 culture, and showed a diverse spectrum of antimicrobial activity of all the tested strains of the genera Lactobacillus and the pathogenic bacteria Staphylococcus aureus and Salmonella аbony. Isoelectric focusing revealed that bacteriocin G 2 is a cationic peptide (pI about 10) with a molecular mass of 2.2 kDa according to tricine-sodium dodecyl sulphate-polyacrylamide gel electrophoresis, SDS-PAGE. The antimicrobial activity of bacteriocin G 2 was diminished by the proteolytic action of trypsin and proteinase K. Bacteriocin G 2 preserved its biological activity in the temperature range 40-60 °C (15 min), which was lost at 80 °C. Bacteriocin G 2 was stable in the pH range 2-9, while treatment with 1 % Tween 80 and 1 % urea resulted in increased antimicrobial activity. The probiotic strain L. plantarum G 2 produces the antimicrobial substance proteinaceous in nature with bacteriocin characteristics. Bacteriocin production is one of the key properties of probiotic bacteria with clinical potential as antiinfective agents, which will increase the likelihood of its in vivo efficacy.
“…Lactocin also had inhibitory capacity on the same microorganism when applied in ground meat [38,39]. Nisin presents desirable properties for food preservation, like the absence of toxicity and undesired taste or flavor, heat and storage stability, is degraded by digestive enzymes, is naturally produced by Lactococcus lactis, and has prominent antimicrobial spectrum against Gram-positive microorganisms [40].…”
The mode of action of an antimicrobial peptide produced by Bacillus sp. P45 isolated from the intestine of the Amazonian basin fish Piaractus mesopotamicus was investigated. The antimicrobial peptide was purified from culture supernatants by precipitation with ammonium sulfate and gel filtration chromatography. The peptide has an EC(50) of 300 AU (activity units) ml(-1) and kills all viable cells of Listeria monocytogenes with a concentration of 800 AU ml(-1). A decrease in OD was observed when L. monocytogenes cultures were treated with the peptide, suggesting that cells were lysed. Transmission electron microscopy showed damage of the cell envelope and loss of protoplasmic material. The peptide P45 was bactericidal and bacteriolytic to L. monocytogenes. There is evidence that the mode of action is interfering at cell membranes and the cell wall. The knowledge of the mode of action of antimicrobial peptides is an essential step to consider their utilization in food or clinic.
“…Nisin, the most studied bacteriocin, is produced by Lactococcus lactis and approved as GRAS (generally recognized as safe) by the Food and Drug Administration (FDA) and safe by the World Health Organization (WHO) as well as the European Union [1,17]. Nisin is active against many Grampositive bacteria including Listeria spp., inhibits clostridial spoilage of processed and natural cheeses and extends the shelf-life of milk in tropical countries.…”
In order to increase nisin production in a cost-effective manner, non-nutritional factors as well as nutritional parameters must be optimized. In this study, optimization of the most important non-nutritional factors for nisin production using orthogonal array method was performed. Optimization of temperature, agitation, age and size of inoculum, medium initial pH value and flask volume/medium volume ratio in de Man, Rogosa and Sharpe (MRS) medium in batch fermentation was accomplished. Nisin was produced by Lactococcus lactis subsp. lactis PTCC 1336 and measured by bioassay method using Micrococcus luteus PTCC 1169 as the nisin-sensitive strain. The optimum levels of non-nutritional factors for maximum nisin production and productivity were obtained as: flask volume/medium volume ratio: 5.00, medium initial pH value: 8.00, inoculum size: 1%, inoculum age: 24 h old (A = 1.7), agitation: 100 rpm and temperature: 27 °C. Under the optimized conditions, maximum nisin production and maximum nisin productivity were 599.70 IU/mL and 37.48 IU/mL/h, respectively.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.