Publications by authors named "Shun Iwatani"

Several probiotic lactic acid bacteria (LAB) exert immunomodulatory effects on the host. However, the reasons for the different effects of LAB have not been fully elucidated. To understand the different immunomodulatory effects of LAB, we evaluated the levels of critical molecules in differentiated monocytic THP-1 and dendritic cells (DCs) following the uptake of various LAB strains.

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Food protein-derived peptides with agonistic effects on receptors have great potential for treating anxiety, hypertension, and stress. In the present study, opioid peptides with agonistic activities for δ-receptor-expressing HEK293 cells were screened from casein hydrolysates prepared with five types of food grade proteolytic enzymes, among which casein hydrolysate with protease ASD showed the highest opioid activity. Eluted fractions showing potent opioid activity were further purified for active peptides by reverse phase-HPLC.

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Article Synopsis
  • Commensal intestinal bacteria in mice interact with gut epithelial cells through binding to specific receptors, but many of these receptors are still unidentified.
  • The study identified a 30 kDa protein, junctional adhesion molecule-2 (JAM-2), which is part of the tight junction protein family, and was found to repair gut barriers damaged in cultured Caco-2 cells when treated with lactic acid bacteria (MG).
  • Additionally, a 40 kDa moonlighting protein, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), was identified, indicating that MG enhances gut barrier integrity through the interaction of GAPDH with JAM-2, highlighting the importance of gut bacteria in host-bacterial communication.
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This study was carried out to evaluate the effects of probiotic C-3102 feed additive on quality characteristics including strength, thickness, and weight of eggshells of Boris Brown laying hens. The control group (=64) was fed a basal diet comprised of maize and feed rice, whereas the experimental group (=64) was fed a basal diet supplemented with C-3102 (3×10 CFU/g) starting at 49 weeks of age. From 67 to 69 weeks, all hens were induced to molt using an anorexic program; then, the birds in both groups returned to their respective diets (from 69 to 82 weeks).

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Enterococcus faecium NKR-5-3 produces multiple-bacteriocins, enterocins NKR-5-3A, B, C, D, and Z (Ent53A, Ent53B, Ent53C, Ent53D, and Ent53Z). However, the biosynthetic mechanisms on how their productions are regulated are yet to be fully understood. In silico analysis revealed putative promoters and terminators in the enterocin NKR-5-3ACDZ gene cluster, and the putative direct repeats (5'-ATTTTAGGATA-3') were conserved upstream of each promoter.

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Among the reported probiotic strains, C-3102 has the unique potential to improve feed uptake under stress conditions in the broilers, piglets, and cows. In this study, we sought to evaluate the protective effect of feed additive probiotic C-3102 against infection of specific pathogen-free (SPF) chicks in floor pens in two experiments. In the experiment-1, the chicks in the control group (=32) were fed a basal diet and those in the C-3102 group (=32) were fed a basal diet supplemented with 1×10 CFU/g of feed for 28 days.

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Biofilm formation of species is considered to be a pathogenic factor of host infection. Since biofilm formation of has not been as well studied as that of , we performed genetic screening of , and three candidate genes associated with biofilm formation were identified. (CAGL0H06325g) was selected as the most induced gene in biofilm cells for further research.

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: is an opportunistic pathogen that causes oral candidiasis. A previous study showed that Bgl2p and Ecm33p may mediate the interaction between the yeast and saliva-coated hydroxyapatite (SHA; a model for the tooth surface). This study investigated the roles of these cell wall proteins in the adherence of to SHA beads.

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NADPH oxidases (Nox) generate reactive oxygen species (ROS) such as superoxide anion radical (O2-) and hydrogen peroxide (H2O2). The pathogenic fungi Candida albicans and Candida glabrata enhance cellular transglutaminase 2 (TG2) activity levels in co-cultured human hepatic cells in a ROS-mediated manner. Deletion of NOX1 (CgNOX1) in C.

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The lipophilic fungal pathogen spp. must acquire long-chain fatty acids (LCFAs) from outside the cell. To clarify the mechanism of LCFA acquisition, we investigated fatty acid uptake by this fungus and identified the long-chain acyl-CoA synthetase (ACS) gene in three spp.

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Candida glabrata represents the second-most frequent cause of candidiasis infections of the mucosa, bloodstream and genito-urinary tract in immunocompromised individuals. The incidence of C glabrata infection has increased significantly in the last two decades, mainly due to this species' abilities to resist various antifungal drugs and to form biofilms. We focused on the relationship between biofilm formation and the product of QDR2, a C glabrata member of the major facilitator superfamily (MFS) gene family, given that fungal biofilm formation limits drug penetration and is associated with persistent infection.

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Glycosylphosphatidylinositol (GPI) is an important compound for the growth of fungi, because GPI-anchored proteins including glycosyltransferases and adhesins are involved in cell-wall integrity, adhesion, and nutrient uptake in this organism. In this study, we examined orf19.5244 in the genome database of the pathogenic fungus Candida albicans, a homologue of the Saccharomyces cerevisiae mannose-ethanolamine phosphotransferase gene, MCD4, which plays a role in GPI synthesis.

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Fatty acyl-CoA synthetase (Faa) activates fatty acid (FA) by converting the FA into the CoA ester in the cell. In the present study, we characterized a FAA homologue (CaFAA4) from the opportunistic pathogen Candida albicans. Most organisms can not only synthesize long-chain fatty acyl-CoAs (LCFA-CoAs) endogenously using a fatty acid synthase (Fas) activity but also can uptake long-chain fatty acids (LCFAs) from the extracellular environment and convert them into LCFA-CoAs via a vectorial acylation system.

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We previously reported the importance of induced nuclear transglutaminase (TG) 2 activity, which results in hepatic cell death, in ethanol-induced liver injury. Here, we show that co-incubation of either human hepatic cells or mouse primary hepatocytes derived from wild-type but not TG2 mice with pathogenic fungi Candida albicans and C. glabrata, but not baker's yeast Saccharomyces cerevisiae, induced cell death in host cells by enhancing cellular, particularly nuclear, TG activity.

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The fungal pathogen Candida albicans undergoes a transition from yeast cells to filamentous cells that is related to its pathogenicity. The complex multicellular processes involved in biofilm formation by this fungus also include this transition. In this work, we investigated the morphological role of the Bgl2 protein (Bgl2p) in the transition to filamentous cells during biofilm formation by C.

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Lacticin Q is an unmodified leaderless bacteriocin produced by Lactococcus lactis QU 5. It has been revealed that the production and self-immunity of lacticin Q are facilitated by a gene cluster lnqQBCDEF The gene for a putative TetR-family transcriptional regulator, termed lnqR, was found nearby the lnqQBCDEF cluster, but its involvement in lacticin Q biosynthesis remained unknown. In this study, we created an LnqR-overexpressing QU 5 recombinant by using lactococcal constitutive promoter P32 The recombinant QU 5 showed enhanced production of and self-immunity to lacticin Q.

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The edible, nitrate assimilating, yeast Candida utilis is a commercial food additive, and it is a potentially useful host for heterologous protein expression. A number of ATP-binding cassette (ABC) transporters are multidrug efflux pumps that can cause multidrug resistance in opportunistic pathogens. In order to develop optimal novel antimicrobial agents it is imperative to understand the structure, function and expression of these transporters.

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Penicilliosis caused by the dimorphic fungus Penicillium marneffei is an endemic, AIDS-defining illness and, after tuberculosis and cryptococcosis, the third most common opportunistic infection of AIDS patients in tropical Southeast Asia. Untreated, patients have poor prognosis; however, primary amphotericin B treatment followed by prolonged itraconazole prophylaxis is effective. To identify ATP-binding cassette (ABC) transporters that may play a role in potential multidrug resistance of P.

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Innate immunity plays important roles in the primary defense against pathogens, and epidemiological studies have suggested a role for Toll-like receptor 1 (TLR1) in Helicobacter pylori susceptibility. Microarray analysis of gastric biopsy specimens from H. pylori-positive and uninfected subjects showed that TLR10 messenger RNA (mRNA) levels were upregulated approximately 15-fold in infected subjects; these findings were confirmed by real-time quantitative polymerase chain reaction analysis.

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The outcomes of Helicobacter pylori infection vary geographically. H pylori strains, disease presentation, and environments differ markedly in Bhutan and Dominican Republic. The aims were to compare the strains, histology, and expression of interleukin (IL) 8 and IL-10 from gastric mucosa from the 2 countries.

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Enterococcus faecium NKR-5-3, isolated from Thai fermented fish, is characterized by the unique ability to produce five bacteriocins, namely, enterocins NKR-5-3A, -B, -C, -D, and -Z (Ent53A, Ent53B, Ent53C, Ent53D, and Ent53Z). Genetic analysis with a genome library revealed that the bacteriocin structural genes (enkA [ent53A], enkC [ent53C], enkD [ent53D], and enkZ [ent53Z]) that encode these peptides (except for Ent53B) are located in close proximity to each other. This NKR-5-3ACDZ (Ent53ACDZ) enterocin gene cluster (approximately 13 kb long) includes certain bacteriocin biosynthetic genes such as an ABC transporter gene (enkT), two immunity genes (enkIaz and enkIc), a response regulator (enkR), and a histidine protein kinase (enkK).

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Helicobacter pylori are Gram-negative, spiral-shaped microaerophilic bacteria etiologically related to gastric cancer. Lactate utilization has been implicated although no corresponding genes have been identified in the H. pylori genome.

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Although the incidence of gastric cancer in the Dominican Republic is not high, the disease remains a significant health problem. We first conducted a detailed analysis of Helicobacter pylori status in the Dominican Republic. In total, 158 patients (103 females and 55 males; mean age 47.

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Objectives: Resistance to clarithromycin is the most important factor causing failure of Helicobacter pylori eradication. Although clarithromycin resistance is mainly associated with three point mutations in the 23S rRNA genes, it is unclear whether other mutations are associated with this resistance.

Methods: Two types of clarithromycin-resistant strains (low- and high-resistance strains) were obtained from clarithromycin-susceptible H.

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