Screening for probiotic properties and potential immunogenic effects of lactobacilli strains isolated from various food products.

Introduction: Deceleration of disease progression and re-establishment of microbial balance in the gut is often achieved by application of lactobacilli strains. Their beneficial effects are associated with probiotic properties, which may be accompanied by immunomodulatory action at mucosal surfaces.

Methods: To single out such strains, we screened almost three hundred lactobacilli isolates from eight genera and various food sources for acid and bile salt tolerance, adhesion to mucin as well as hemolytic activity and antibiotic susceptibility.

The Effect of LPC100 and LP140 on Bone Mineral Density in Postmenopausal Women: A Multicenter, Randomized, Placebo-Controlled Study.

modulation of gut microbiota by probiotics has been proposed as a target for intervention to reduce bone mineral density (BMD) loss in the postmenopausal period. This study aims to evaluate the effect of (L.) LPC100 and (L.

Complete genome sequence of the probiotic LPC100 strain from the NORDBIOTIC collection isolated from a human fecal sample.

We report the genome sequence of the human fecal isolate LPC100 from the NORDBIOTIC collection, comprising a 3.075 Mb chromosome and three plasmids (61 kb, 12 kb, and 7 kb). Genetic content reveals the strain's beneficial features-complete lactose metabolic pathway, potential production of bacteriocins, and short-chain fatty acids.

Whole-genome sequencing and characterization of human fecal isolate LC130 from NORDBIOTIC collection.

We report the complete genome sequence of LC130, isolated from a healthy human fecal sample and part of the NORDBIOTIC collection. The 2.969 Mb genome of LC130 includes genes potentially involved in lactose metabolism and the production of bacteriocins, peptidases, and polyamines, suggesting potential health benefits.

Exploring the role of phage plasmids in gene transfers.

Bacteriophages and plasmids drive horizontal gene transfer (HGT) in bacteria. Phage-plasmids (P-Ps) are hybrids of plasmid and phages. Pfeifer and Rocha recently demonstrated that P-Ps can serve as intermediates in gene exchanges between these two types of elements, identified categories of preferentially transferred genes, and reconstructed gene flows involving phage P1-like P-Ps.

Reducing Immunoreactivity of Gluten Peptides by Probiotic Lactic Acid Bacteria for Dietary Management of Gluten-Related Diseases.

Immunoreactive gluten peptides that are not digested by peptidases produced by humans can trigger celiac disease, allergy and non-celiac gluten hypersensitivity. The aim of this study was to evaluate the ability of selected probiotic strains to hydrolyze immunoreactive gliadin peptides and to identify peptidase-encoding genes in the genomes of the most efficient strains. Residual gliadin immunoreactivity was measured after one- or two-step hydrolysis using commercial enzymes and bacterial peptidase preparations by G12 and R5 immunoenzymatic assays.

The strain-dependent cytostatic activity of Lactococcus lactis on CRC cell lines is mediated through the release of arginine deiminase.

Background: Colorectal cancer (CRC) is one of the most commonly diagnosed cancers, posing a serious public health challenge that necessitates the development of new therapeutics, therapies, and prevention methods. Among the various therapeutic approaches, interventions involving lactic acid bacteria (LAB) as probiotics and postbiotics have emerged as promising candidates for treating and preventing CRC. While human-isolated LAB strains are considered highly favorable, those sourced from environmental reservoirs such as dairy and fermented foods are also being recognized as potential sources for future therapeutics.

Health-Promoting Nature of IBB109 and IBB417 Strains Exhibiting Proliferation Inhibition and Stimulation of Interleukin-18 Expression in Colorectal Cancer Cells.

Lactic acid bacteria (LAB) are Gram-positive bacteria which are considered for use as adjuvant therapeutics in management of various disease ailments, including obesity, irritable bowel syndrome, lactose intolerance and cancer. To investigate the possible use of strains from our collection in treatment of gastrointestinal cancer, we tested them for the ability to arrest proliferation of human colorectal adenocarcinoma cells (Caco-2). Results of the BrdU assay showed that the anti-proliferative activity of cells is strain-specific.

An Adenosine Triphosphate- Dependent 5'-3' DNA Helicase From sk1-Like F13 Phage.

Here, we describe functional characterization of an early gene () product of a virulent sk1like phage, vB_Llc_bIBBF13 (abbr. F13). The GP46 protein carries a catalytically active RecA-like domain belonging to the P-loop NTPase superfamily.

Expanding Diversity of Single-Strand Annealing Proteins: A Putative Role of Bacteriophage-Host Arms Race.

Bacteriophage-encoded single strand annealing proteins (SSAPs) are recombinases which can substitute the classical, bacterial RecA and manage the DNA metabolism at different steps of phage propagation. SSAPs have been shown to efficiently promote recombination between short and rather divergent DNA sequences and were exploited for genetic engineering mainly in Gram-negative bacteria. In opposition to the conserved and almost universal bacterial RecA protein, SSAPs display great sequence diversity.

Phages Isolated from Industrial Dairy Plants-from Physiological to Genomic Analyses.

(formerly c2) bacteriophages are among the three most prevalent phage types reported in dairy environments. Phages from this group conduct a strictly lytic lifestyle and cause substantial losses during milk fermentation processes, by infecting lactococcal host starter strains. Despite their deleterious activity, there are limited research data concerning phages.

Recombinant Expressing Haemagglutinin from a Polish Avian H5N1 Isolate and Its Immunological Effect in Preliminary Animal Trials.

Lactic acid bacteria (LAB) are Gram-positive, nonpathogenic microorganisms that are gaining much interest as antigen producers for development of live vaccine vectors. Heterologous proteins of different origin have been successfully expressed in various LAB species, including . Recombinant strains have been shown to induce specific local and systemic immune responses against various antigens.

Oral Administration of Lactococcus lactis Expressing Synthetic Genes of Myelin Antigens in Decreasing Experimental Autoimmune Encephalomyelitis in Rats.

Background: Multiple sclerosis is a human autoimmunological disease that causes neurodegeneration. One of the potential ways to stop its development is induction of oral tolerance, whose effect lies in decreasing immune response to the fed antigen. It was shown in animal models that administration of specific epitopes of the three main myelin proteins - myelin oligodendrocyte glycoprotein (MOG), myelin basic protein (MBP), and proteolipid protein (PLP) - results in induction of oral tolerance and suppression of disease symptoms.

Expression of avian influenza haemagglutinin (H5) and chicken interleukin 2 (chIL-2) under control of the ptcB promoter in Lactococcus lactis.

Gram-positive and nonpathogenic lactic acid bacteria (LAB) are considered to be promising candidates for the development of new, safe systems of heterologous protein expression. Recombinant LAB has been shown to induce specific local and systemic immune response against selected pathogens, and could be a good alternative to classical attenuated carriers. The main goal of our study was to express the avian influenza haemagglutinin (H5) and chicken interleukin 2 (chIL-2) in Lactococcus lactis.

Phylogenetic and complementation analysis of a single-stranded DNA binding protein family from lactococcal phages indicates a non-bacterial origin.

Background: The single-stranded-nucleic acid binding (SSB) protein superfamily includes proteins encoded by different organisms from Bacteria and their phages to Eukaryotes. SSB proteins share common structural characteristics and have been suggested to descend from an ancestor polypeptide. However, as other proteins involved in DNA replication, bacterial SSB proteins are clearly different from those found in Archaea and Eukaryotes.