: A Source of Postbiotics Displaying Anti-Inflammatory Effects in THP 1 Macrophages.

In addition to traditional use in fermented dairy products, also exhibits anti-inflammatory properties both in live and heat-inactivated form. Recent studies have highlighted that some hydrolysates from surface proteins of could be responsible partially for overall anti-inflammatory activity of this bacterium. It was hypothesized that anti-inflammatory activity could also be attributed to peptides resulting from the digestion of intracellular proteins of .

Impact of Dietary Arachidonic Acid on Gut Microbiota Composition and Gut-Brain Axis in Male BALB/C Mice.

Although arachidonic acid (ARA) is the precursor of the majority of eicosanoids, its influence as a food component on health is not well known. Therefore, we investigated its impact on the gut microbiota and gut-brain axis. Groups of male BALB/c mice were fed either a standard diet containing 5% lipids (Std-ARA) or 15%-lipid diets without ARA (HL-ARA) or with 1% ARA (HL + ARA) for 9 weeks.

Cell Proteins Obtained by Peptic Shaving of Two Phenotypically Different Strains of as a Source of Anti-Inflammatory Peptides.

, a food grade bacterium, is extensively used in the manufacture of fermented products such as yogurt and cheeses. It has been shown that strains exhibited varying anti-inflammatory activities in vitro. Our previous study displayed that this activity could be partially due to peptide(s) generated by trypsin hydrolysis of the surface proteins of LMD-9.

In Vitro Anti-Inflammatory Activity of Peptides Obtained by Tryptic Shaving of Surface Proteins of LMD-9.

, a lactic acid bacterium widely used in the dairy industry, is consumed regularly by a significant proportion of the population. Some strains show in vitro anti-inflammatory activity which is not fully understood. We hypothesized that peptides released from the surface proteins of this bacterium during digestion could be implied in this activity.

Role of the Sortase A in the Release of Cell-Wall Proteinase PrtS in the Growth Medium of 4F44.

Growth of the lactic acid bacterium in milk depends on its capacity to hydrolyze proteins of this medium through its surface proteolytic activity. Thus, strains exhibiting the cell envelope proteinase (CEP) PrtS are able to grow in milk at high cellular density. Due to its LPNTG motif, which is possibly the substrate of the sortase A (SrtA), PrtS is anchored to the cell wall in most strains.

Identification of Genes Specifically Expressed under Simulated Human Digestive Conditions Using R-IVET Technology.

Despite promising health effects, the probiotic status of a lactic acid bacterium widely used in dairy industry, requires further documentation of its physiological status during human gastrointestinal passage. This study aimed to apply recombinant-based in vivo technology (R-IVET) to identify genes triggered in a LMD-9 reference strain under simulated digestive conditions. First, the R-IVET chromosomal cassette and plasmid genomic library were designed to positively select activated genes.

Importance of digestive mucus and mucins for designing new functional food ingredients.

The mucus, mainly composed of the glycoproteins mucins, is a rheological substance that covers the intestinal epithelium and acts as a protective barrier against a variety of harmful molecules, microbial infection and varying lumen environment conditions. Alterations in the composition or structure of the mucus could lead to various diseases such as inflammatory bowel disease or colorectal cancer. Recent studies revealed that an exogenous intake of probiotic bacteria or other dietary components (such as bioactive peptides and probiotics) derived from food influence mucus layer properties as well as modulate gene expression and secretion of mucins.

The X-prolyl dipeptidyl-peptidase PepX of Streptococcus thermophilus initially described as intracellular is also responsible for peptidase extracellular activity.

This study addresses the hypothesis that the extracellular cell-associated X-prolyl dipeptidyl-peptidase activity initially described in Streptococcus thermophilus could be attributable to the intracellular X-prolyl dipeptidyl-peptidase PepX. For this purpose, a PepX-negative mutant of S. thermophilus LMD-9 was constructed by interrupting the pepX gene and named LMD-9-ΔpepX.

Implication of sortase-dependent proteins of Streptococcus thermophilus in adhesion to human intestinal epithelial cell lines and bile salt tolerance.

Streptococcus thermophilus (ST) is a lactic acid bacterium widely used in dairy industry and displays several properties which could be beneficial for host. The objective of this study was to investigate, in vitro, the implication of sortase A (SrtA) and sortase-dependent proteins (SDPs) in the adhesion of ST LMD-9 strain to intestinal epithelial cells (IECs) and resistance to bile salt mixture (BSM; taurocholoate, deoxycholate, and cholate). The effect of mutations in prtS (protease), mucBP (MUCin-Binding Protein), and srtA genes in ST LMD-9 in these mechanisms were examined.