Characterization of the membrane vesicle fraction from Acetobacter sp. WSS15.

A bacterium that produces membrane vesicles (MVs), strain WSS15, was isolated from a traditional vinegar in Japan called Kurozu. A phylogenetic analysis of 16S rRNA gene sequences indicated that this bacterium belongs to the genus Acetobacter. MVs and peptidoglycan-associated lipoprotein (Pal) were detected in the MV fraction of strain WSS15.

Immunostimulatory activity of lipoteichoic acid with three fatty acid residues derived from JCM 15950.

Unlabelled: Some strains of lactic acid bacteria can regulate the host's intestinal immune system. Bacterial cells and membrane vesicles (MVs) of JCM 15950 promote immunoglobulin A (IgA) production in murine Peyer's patch cells via toll-like receptor (TLR) 2. This study aimed to investigate the role of lipoteichoic acid (LTA), a ligand of TLR2, in the immunostimulatory activity of these bacterial cells and their MVs.

RNA-Based Anti-Inflammatory Effects of Membrane Vesicles Derived from .

Bacteria generally release extracellular membrane vesicles (MVs), which are nanoparticles that play important roles in bacterial-bacterial and bacterial-host communication. As probiotics, lactic acid bacteria provide diverse health benefits to their hosts. In this study, we found that the Gram-positive lactic acid bacteria subsp.

High productivity of immunostimulatory membrane vesicles of using glycine.

Nanosized membrane vesicles (MVs) released by bacteria play important roles in both bacteria-bacteria and bacteria-host interactions. Some gram-positive lactic acid bacteria produce MVs exhibiting immunoregulatory activity in the host. We found that both bacterial cells and MVs of JCM 15950, isolated from the human stomach mucosa, enhance immunoglobulin A production by murine Peyer's patch cells.

Analysis of the effects of specific growth rate of Lactococcus lactis MG1363 on aerobic metabolism and its application to high-density culture.

Lactic acid bacteria (LAB) are known to produce a large amount of lactate when cultured under non-aerated conditions, which inhibits their growth at high concentrations. Our previous studies have shown that LAB can be cultured without lactate production under aerated conditions at a low specific growth rate. In this study, we investigated the effects of specific growth rate on cell yield and the specific production rates of metabolites in aerated fed-batch cultures of Lactococcus lactis MG1363.

Activation of the toll-like receptor 2 signaling pathway by GAPDH from bacterial strain RD055328.

We characterized the membrane vesicle fraction (RD-MV fraction) from bacterial strain RD055328, which is related to members of the genus Companilactobacillus and Lactiplantibacillus plantarum. RD-MVs and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) were detected in the RD-MV fraction. Immunoglobulin A (IgA) was produced by Peyer's patch cells following the addition of the RD-MV fraction.

Enhancement of IgA production by membrane vesicles derived from Bifidobacterium longum subsp. infantis.

Immunoglobulin A (IgA) is involved in the maintenance of gut homeostasis. Although the oral administration of bifidobacteria increases the amount of fecal IgA, the effects of bifidobacteria on intestinal immunity remain unclear. We found and characterized membrane vesicles (MVs) derived from Bifidobacterium longum subsp.

Characterization of extracellular vesicles from Lactiplantibacillus plantarum.

We investigated the characteristics and functionalities of extracellular vesicles (EVs) from Lactiplantibacillus plantarum (previously Lactobacillus plantarum) towards host immune cells. L. plantarum produces EVs that have a cytoplasmic membrane and contain cytoplasmic metabolites, membrane and cytoplasmic proteins, and small RNAs, but not bacterial cell wall components, namely, lipoteichoic acid and peptidoglycan.

Betulin Attenuates TGF-β1- and PGE-Mediated Inhibition of NK Cell Activity to Suppress Tumor Progression and Metastasis in Mice.

Transforming growth factor (TGF)-β1 and prostaglandin E (PGE) are humoral factors critically involved in the induction of immunosuppression in the microenvironment of various types of tumors, including melanoma. In this study, we identified a natural compound that attenuated TGF-β1- and PGE-induced immunosuppression and examined its effect on B16 melanoma growth in mice. By screening 502 natural compounds for attenuating activity against TGF-β1- or PGE-induced suppression of cytolysis in poly(I:C)-stimulated murine splenocytes, we found that betulin was the most potent compound.

Mechanisms underlying enhanced IgA production in Peyer's patch cells by membrane vesicles derived from Lactobacillus sakei.

We analyzed the mechanisms underlying enhanced IgA production in the cells of Peyer's patch cells via membrane vesicles derived from Lactobacillus sakei subsp. sakei NBRC 15893. Depletion of CD11c+ cells from Peyer's patch cells suppressed the enhanced IgA production mediated by membrane vesicles.

Adhesion mechanisms of subsp. JCM 10602 to dietary fiber.

Adherence of probiotics to dietary fibers present in the intestinal tract may affect adhesion to intestinal epithelial cells. The properties of the adhesion of bifidobacteria to mucin or epithelial cells have been well studied; however, adhesion of bifidobacteria to dietary fiber has not been investigated. The adhesion ratio of six strains to cellulose and chitin was examined; among the strains, subsp.

Suppression of lactate production by aerobic fed-batch cultures of Lactococcus lactis.

Aerobic fed-batch cultures were studied as a means of suppressing the production of lactate, which inhibits the growth of lactic acid bacteria (LAB). LAB produce lactate via lactate dehydrogenase (LDH), regenerating nicotinamide adenine dinucleotide (NAD) consumed during glycolysis. Therefore, we focused on NADH oxidase (NOX), employing oxygen as an electron acceptor, as an alternative pathway to LDH for NAD regeneration.

Suppression of lactate production of Lactobacillus reuteri JCM1112 by co-feeding glycerol with glucose.

Lactate produced by lactic acid bacteria inhibits their growth. To suppress lactate production, it is necessary to regenerate NAD consumed by glycolysis with alternative pathways other than lactate dehydrogenase. In a heterofermentative lactic acid bacterium, Lactobacillus reuteri JCM1112, suppression of lactate production by regenerating NAD when producing 1,3-propanediol from glycerol was investigated.

Suppression of lactate production by using sucrose as a carbon source in lactic acid bacteria.

Lactic acid bacteria (LAB) grow by producing lactate from sugar. However, the accumulation of lactate inhibits their growth. Here, the lactate productivity per cell in a semi-solid medium prepared with a chlorella powder in several LAB strains was much lower than that in the conventional MRS medium.

IgA-enhancing effects of membrane vesicles derived from subsp. NBRC15893.

Immunoglobulin (Ig) A in the mucus of the intestinal tract plays an important role in preventing the invasion of pathogenic microorganisms and regulating the composition of the gut microbiota. Several strains of probiotic lactic acid bacteria (LAB) are known to promote intestinal IgA production. Bacteria are also known to naturally release spherical membrane vesicles (MVs) that are involved in various biological functions such as quorum sensing, pathogenesis, and host immunomodulation.

Characterization and gene cloning of l-xylulose reductase involved in l-arabinose catabolism from the pentose-fermenting fungus Rhizomucor pusillus.

l-Xylulose reductase (LXR) catalyzes the reduction of l-xylulose to xylitol in the fungal l-arabinose catabolic pathway. LXR (RpLXR) was purified from the pentose-fermenting zygomycetous fungus Rhizomucor pusillus NBRC 4578. The native RpLXR is a homotetramer composed of 29 kDa subunits and preferred NADPH as a coenzyme.

Analysis of gene expression profiles of induced by direct contact with through recognition of yeast mannan.

Co-culture of lactic acid bacteria (LAB) and yeast induces specific responses that are not observed in pure culture. Gene expression profiles of ATCC 334 co-cultured with IFO 0216 were analyzed by DNA microarray, and the responses induced by direct contact with the yeast cells were investigated. Coating the LAB cells with recombinant DnaK, which acts as an adhesive protein between LAB and yeast cells, enhanced the ratio of adhesion of the LAB cells to the yeast cells.

Identification and characterization of D-xylulokinase from the D-xylose-fermenting fungus, Mucor circinelloides.

D-Xylulokinase catalyzes the phosphorylation of D-xylulose in the final step of the pentose catabolic pathway to form d-xylulose-5-phosphate. The D-xylulokinase activity was found to be induced by both D-xylose and L-arabinose, as well as some of the other enzymes involved in the pentose catabolism, in the D-xylose-fermenting zygomycetous fungus, Mucor circinelloides NBRC 4572. The putative gene, xyl3, which may encode D-xylulokinase, was detected in the genome sequence of this strain.

Molecular analysis of NAD⁺-dependent xylitol dehydrogenase from the zygomycetous fungus Rhizomucor pusillus and reversal of the coenzyme preference.

The zygomycetous fungus Rhizomucor pusillus NBRC 4578 is able to ferment not only d-glucose but also d-xylose into ethanol. Xylitol dehydrogenase from R. pusillus NBRC 4578 (RpXDH), which catalyzes the second step of d-xylose metabolism, was purified, and its enzymatic properties were characterized.

Identification and characterization of D-xylose reductase involved in pentose catabolism of the zygomycetous fungus Rhizomucor pusillus.

Rhizomucor pusillus NBRC 4578 efficiently produces ethanol from lignocellulosic biomass because of its ability to ferment not only d-glucose, but also d-xylose. When the strain was cultivated on d-xylose, ethanol was gradually formed in the culture medium with a decrease in d-xylose and the simultaneous accumulation of xylitol, which suggested that the strain catabolized d-xylose with d-xylose reductase (XR) and xylitol dehydrogenase (XDH). XR (RpXR) was purified to homogeneity from the crude extract prepared from the mycelia of the strain grown on d-xylose.

Determination of L-methionine using methionine-specific dehydrogenase for diagnosis of homocystinuria due to cystathionine β-synthase deficiency.

To determine the L-methionine (L-Met) concentration in an extract from dried blood spots (DBSs) for newborn mass screening for homocystinuria (HCU) due to cystathionine β-synthase (CBS) deficiency, a new fluorometric microplate assay using a methionine-specific dehydrogenase (MetDH) and the diaphorase/reazusrin system was established. We created by directed mutagenesis an NAD⁺-dependent MetDH from phenylalanine dehydrogenase (PheDH) showing higher substrate specificity toward L-Met than L-phenylalanine (L-Phe). However, it also exhibited notable activity for branched-chain amino acids (BCAAs).