Previously, the protective role of the S-layer protein 2 (Slp2) of the vaginal
2029 (LC2029) strain against foodborne pathogens
,
serovar Enteritidis, and
O157:H was demonstrated. We demonstrate the ...new roles of the Slp2-positive LC2029 strain and soluble Slp2 against
infections. We show that LC2029 bacteria can adhere to the surface of the cervical epithelial HeLa cells, prevent their contact with
, and block yeast transition to a pathogenic hyphal form. Surface-bound Slp2 provides the ability for LC2029 to co-aggregate with various
strains, including clinical isolates.
-induced necrotizing epithelial damage is reduced by colonization with the Slp2-positive LC2029 strain. Slp2 inhibits the adhesion of various strains of
to different human epithelial cells, blocks yeast transition to a pathogenic hyphal form, and prevents the colonization and pathogenic infiltration of mucosal barriers. Only Slp2 and LC2029 bacteria stimulate the production of protective human β-defensin 3 in various epithelial cells. These findings support the anti-
potential of the probiotic LC2029 strain and Slp2 and form the basis for further research on their ability to prevent and manage invasive
infections.
The Ligilactobacillus salivarius 7247 (LS7247) strain, originally isolated from a healthy woman’s intestines and reproductive system, has been studied for its probiotic potential, particularly ...against Salmonella Enteritidis (SE) and Salmonella Typhimurium (ST) as well as its potential use in synbiotics. LS7247 showed high tolerance to gastric and intestinal stress and effectively adhered to human and animal enterocyte monolayers, essential for realizing its probiotic properties. LS7247 showed high anti-Salmonella activity. Additionally, the cell-free culture supernatant (CFS) of LS7247 exhibited anti-Salmonella activity, with a partial reduction upon neutralization with NaOH (p < 0.05), suggesting the presence of anti-Salmonella factors such as lactic acid (LA) and bacteriocins. LS7247 produced a high concentration of LA, reaching 124.0 ± 2.5 mM after 48 h of cultivation. Unique gene clusters in the genome of LS7247 contribute to the production of Enterolysin A and metalloendopeptidase. Notably, LS7247 carries a plasmid with a gene cluster identical to human intestinal strain L. salivarius UCC118, responsible for class IIb bacteriocin synthesis, and a gene cluster identical to porcine strain L. salivarius P1ACE3, responsible for nisin S synthesis. Co-cultivation of LS7247 with SE and ST pathogens reduced their viability by 1.0–1.5 log, attributed to cell wall damage and ATP leakage caused by the CFS. For the first time, the CFS of LS7247 has been shown to inhibit adhesion of SE and ST to human and animal enterocytes (p < 0.01). The combination of Actigen prebiotic and the CFS of LS7247 demonstrated a significant combined effect in inhibiting the adhesion of SE and ST to human and animal enterocytes (p < 0.001). These findings highlight the potential of using the LS7247 as a preventive strategy and employing probiotics and synbiotics to combat the prevalence of salmonellosis in animals and humans caused by multidrug resistant (MDR) strains of SE and ST pathogens.
The V antigen (LcrV) of the plague bacterium Yersinia pestis is a potent protective protein that is considered as a vaccine component for humans. LcrV mediates the delivery of Yop toxins into host ...cells and upregulates TLR2-dependent IL-10 production. Although LcrV can interact with the receptor-bound human interferon-γ (hIFN-γ), the significance of these interactions in plague pathogenesis is not known. In this study, we determined the parameters of specific interactions of LcrV and LcrV68–326 with primary human thymocytes and Jurkat T-leukemia cells in the presence of receptor-bound hIFN-γ. Although the C-terminal region of hIFN-γ contains a GRRA138–141 site needed for high-affinity binding of LcrV and LcrV68–326, in the hIFN-γ homodimer, these GRRA138–141 target sites becomes accessible for targeting by LcrV or LcrV68–326 only after immobilization of the hIFN-γ homodimer on the hIFN-γ receptors of thymocytes or Jurkat T-cells. The interaction of LcrV or LcrV68–326 with receptor-bound hIFN-γ on the thymocytes or Jurkat T-cells caused apoptosis of both cell types, which can be completely blocked by the addition of monoclonal antibodies specific to the LEEL32–35 and DEEI203–206 sites of LcrV. The ability of LcrV to utilize hIFN-γ is insidious and may account in part for the severe symptoms of plague in humans.
Given the growth, complexity, and size of the Internet, new methodologies are needed to support cost-effective resource provisioning. This paper provides a cost-based polynomial-time heuristic ...algorithm for resource provisioning optimization called multi-layered market algorithm (MMA). The MMA is solvable for multi-layered, multi-technology, and practical-sized networks, where the traffic is modeled as a combination of constant bit-rate and variable bit-rate (VBR) traffic streams. A VBR stream is modeled either by a Gaussian process or by a Poisson Pareto burst process (PPBP) which under certain parameter values is long-range dependent - a known characteristic of the Internet traffic streams. The consideration of VBR traffic models in a multi-layered network optimization is a key novel aspect of MMA. The MMA considers a range of transport technologies operating in layers and traffic sharing schemes. The MMA implements flow-size-based routing where flows according to their sizes are routed independently. As routing affects resource requirement, such considerations are important for resource provisioning by the given cost models. The complexity resulting from these considerations, including layering and PPBP traffic, requires a simplified design philosophy which in this paper, is based on adopting the shortest path routing in each layer. This is achieved by MMA which is based on an iterative algorithm, and resource provisioning that is performed link-by-link in all layers. As a benchmark for MMA, we provide an integer linear programming (ILP) formulation for a multi-layered network optimization problem with fixed end-to-end demands. The MMA is validated by comparing its solutions to those ILP results in different variants of a six-node network, and its software is verified using double-entry bookkeeping - a method commonly used in accounting systems. The MMA runs on a platform called network mark-up language, which enables visualization and further validation of the results.
LF3872 was isolated from the milk of a healthy lactating and breastfeeding woman. Earlier, the genome of LF3872 was sequenced, and a gene encoding unique bacteriocin was discovered. We have shown ...here that the LF3872 strain produces a novel thermolabile class III bacteriolysin (BLF3872), exhibiting antimicrobial activity against antibiotic-resistant
strains. Sequence analysis revealed the two-domain structural (lysozyme-like domain and peptidase M23 domain) organization of BLF3872. At least 25% residues of this protein are expected to be intrinsically disordered. Furthermore, BLF3872 is predicted to have a very high liquid-liquid phase separation. According to the electron microscopy data, the bacterial cells of LF3872 strain form co-aggregates with the
8325-4 bacterial cells. LF3872 produced bacteriolysin BLF3872 that lyses the cells of the
8325-4 mastitis-inducing strain. The sensitivity of the antibiotic-resistant
collection strains and freshly isolated antibiotic-resistant strains was tested using samples from women with lactation mastitis; the human nasopharynx and oral cavity; the oropharynx of pigs; and the cows with a diagnosis of clinical mastitis sensitive to the lytic action of the LF3872 strain producing BLF3872. The co-cultivation of LF3872 strain with various antibiotic-resistant
strains for 24 h reduced the level of living cells of these pathogens by six log. The LF3872 strain was found to be able to co-aggregate with all studied
strains. The cell-free culture supernatant of LF3872 (CSLF3872) induced
cell damage and ATP leakage. The effectiveness of the bacteriolytic action of LF3872 strain did not depend on the origin of the
strains. The results reported here are important for the creation of new effective drugs against antibiotic-resistant strains of
circulating in humans and animals.
Limosilactobacillus fermentum strain 3872 (LF3872) was originally isolated from the breast milk of a healthy woman during lactation and the breastfeeding of a child. Ligilactobacillus salivarius ...strain 7247 (LS7247) was isolated at the same time from the intestines and reproductive system of a healthy woman. The genomes of these strains contain genes responsible for the production of peptidoglycan-degrading enzymes and factors that increase the permeability of the outer membrane of Gram-negative pathogens. In this work, the anti-Salmonella and intestinal homeostatic features of the LF3872 and LS7247 consortium were studied. A multi-drug resistant (MDR) strain of Salmonella enteritidis (SE) was used in the experiments. The consortium effectively inhibited the adhesion of SE to intact and activated human, porcine, and chicken enterocytes and reduced invasion. The consortium had a bactericidal effect on SE in 6 h of co-culturing. A gene expression analysis of SE showed that the cell-free supernatant (CFS) of the consortium inhibited the expression of virulence genes critical for the colonization of human and animal enterocytes. The CFS stimulated the production of an intestinal homeostatic factor—intestinal alkaline phosphatase (IAP)—in Caco-2 and HT-29 enterocytes. The consortium decreased the production of pro-inflammatory cytokines IL-8, TNF-α, and IL-1β, and TLR4 mRNA expression in human and animal enterocytes. It stimulated the expression of TLR9 in human and porcine enterocytes and stimulated the expression of TLR21 in chicken enterocytes. The consortium also protected the intestinal barrier functions through the increase of transepithelial electrical resistance (TEER) and the inhibition of paracellular permeability in the monolayers of human and animal enterocytes. The results obtained suggest that a LF3872 and LS7247 consortium can be used as an innovative feed additive to reduce the spread of MDR SE among the population and farm animals.
We provide numerical procedures for possibly best evaluating the sum of
positive series under quite general setting. Our procedures are based on the
application of a generalized version of Kummer's ...test.
Limosilactobacillus fermentum strain 3872 (LF3872) was originally isolated from the breast milk of a healthy woman during lactation and the breastfeeding of a child. The high-quality genome ...sequencing of LF3872 was performed, and a gene encoding a unique bacteriocin was discovered. It was established that the bacteriocin produced by LF3872 (BLF3872) belongs to the family of cell-wall-degrading proteins that cause cell lysis. The antibacterial properties of LF3872 were studied using test cultures of antibiotic-resistant Gram-positive and Gram-negative pathogens. Gram-positive pathogens (Staphylococcus aureus strain 8325-4 and S. aureus strain IIE CI-SA 1246) were highly sensitive to the bacteriolytic action of LF3872. Gram-negative pathogens (Escherichia coli, Salmonella strains, and Campylobacter jejuni strains) were more resistant to the bacteriolytic action of LF3872 compared to Gram-positive pathogens. LF3872 is a strong co-aggregator of Gram-negative pathogens. The cell-free culture supernatant of LF3872 (CSLF3872) induced cell damage in the Gram-positive and Gram-negative test cultures and ATP leakage. In the in vitro experiments, it was found that LF3872 and Actigen prebiotic (Alltech Inc., Nicholasville, KY, USA) exhibited synergistic anti-adhesive activity against Gram-negative pathogens. LF3872 has immunoregulatory properties: it inhibited the lipopolysaccharide-induced production of proinflammatory cytokines IL-8, IL-1β, and TNF-α in a monolayer of Caco-2 cells; inhibited the production of IL-12 and stimulated the production of IL-10 in immature human dendritic cells; and stimulated the production of TGF-β, IFN-γ, and IgA in the immunocompetent cells of intestinal Peyer’s patches (PPs) in mice. These results indicate the possibility of creating a synbiotic based on LF3872 and a prebiotic derived from Saccharomyces cerevisiae cell wall components. Such innovative drugs and biologically active additives are necessary for the implementation of a strategy to reduce the spread of antibiotic-resistant strains of socially significant animal and human infections.
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