The aim of this work was to study the significance urease enzyme in promoting Helicobacter pylori survival various environments. A urease-positive H. isolate, strain N6, and an isogenic urease-negative strain, N6(ureB::TnKm), were incubated phosphate-buffered saline at a pH ranging from 2.2 7.2 for 60 min 37 degrees C both presence absence 10 mM urea. number CFU per milliliter each solution, bacterial supernatant, amounts ammonia present solutions measured. N6 survived well with values 4.5...

Helicobacter pylori is a highly successful pathogen uniquely adapted to colonize humans. Gastric infections with this bacterium can induce pathology ranging from chronic gastritis and peptic ulcers gastric cancer. More virulent H. isolates harbour numerous well-known adhesins (BabA/B, SabA, AlpA/B, OipA HopZ) the cag (cytotoxin-associated genes) pathogenicity island encoding type IV secretion system (T4SS). The establish tight bacterial contact host target cells T4SS represents needle-like...

Campylobacter jejuni is a common cause of serious diarrhoeal disease in humans, contrast to the avian population, where exposure results prolonged colonization at high density without disease. Colonized poultry present significant source infection humans worldwide. The aim this work was compare interaction with primary intestinal cells from and identify factors that account for divergent outcome following exposure. A cell model developed using grown human chicken biopsies. cultured were...

In this study, we tested the hypothesis that milk oligosaccharides may contribute not only to selective growth of bifidobacteria, but also their specific adhesive ability. Human (3′sialyllactose and 6′sialyllactose) a commercial prebiotic (Beneo Orafti P95; oligofructose) were assayed for ability promote adhesion Bifidobacterium longum subsp. infantis ATCC 15697 HT-29 Caco-2 human intestinal cells. Treatment with or 3′sialyllactose did enhance adhesion. However, treatment 6′sialyllactose...

ABSTRACT The HT29MTXE12 (E12) cell line harbors an adherent mucus layer, providing a novel technique to model mucosal infection in vitro . In this study, we have characterized the interaction of Campylobacter jejuni with E12 and exploited its unique layer examine potential efficacy probiotic treatment attenuate C. virulence properties. 81-176 colonized reproduced mucus. Adhesion internalization were enhanced cells harboring compared parental without Translocation occurred at early time...

Why Helicobacter pylori colonizes only gastric tissue is unknown. It found on mucus-secreting cells and in the overlying mucus but not deep glands. This localization mirrors expression of trefoil factor 1, TFF1. We hypothesized that H. interacting with TFF1 could explain tropism this bacteria for tissue. Recombinant human expressed Escherichia coli was purified by affinity chromatography, ion-exchange gel filtration. Binding assessed using flow cytometry BIAcore system, which allows...

Abstract Helicobacter pylori infections and clinical outcome are dependent on sophisticated interactions between the bacteria its host. Crucial bacterial factors associated with pathogenicity comprise a type IV secretion system encoded by cag island, effector protein CagA, vacuolating cytotoxin (VacA), peptidoglycan, lipopolysaccharide (LPS), γ‐glutamyl transpeptidase (GGT), protease HtrA, adhesins BabA, SabA, others. The high number of these allelic variation involved genes generates highly...

Background Akkermansia muciniphila and Desulfovibrio spp. are commensal microbes colonising the mucus gel layer of colon. Both species have capacity to utilise colonic mucin as a substrate. A. degrades mucin, while metabolise sulfate moiety sulfated mucins. Altered abundances these microorganisms been reported in ulcerative colitis (UC). However their bind human whether this binding is affected by changes associated with UC, remain be defined. Methods Mucin was isolated from resected colon...

Helicobacter pylori adheres only to gastric cells in vivo. However, the organism a wide variety of nongastric vitro. In this study, we have used flow cytometry assess adherence H. primary epithelial isolated from gastric, duodenal, and colonic biopsy specimens by collagenase digestion. After incubation bacteria together subsequent staining with two-stage fluorescein isothiocyanate-labelled antibody method, adherent could be easily distinguished without bacteria. Binding Kato III (a...

Campylobacter jejuni is a major causative agent of diarrhoeal disease worldwide in the human population. In contrast, heavy colonization poultry typically does not lead to and colonized chickens are source infections humans. Previously, we have shown that chicken (but human) intestinal mucus inhibits C. internalization. this study, test hypothesis mucin, main component mucus, responsible for inhibition virulence. Purified mucin attenuated binding internalization into HCT-8 cells depending on...

ABSTRACT Helicobacter pylori and Campylobacter jejuni colonize the stomach intestinal mucus, respectively. Using a combination of mucus-secreting cells, purified mucins, novel mucin microarray platform, we examined interactions these two organisms with mucus mucins. H. C. bound to distinctly different displayed striking tropism for chicken gastrointestinal mucins compared from other animals preferentially specific avian sites (in order descending preference: large intestine, proximal small...

ABSTRACT Background. The lipopolysaccharide of Helicobacter pylori plays an important role in colonization and pathogenicity. present study sought to compare structural biological features lipopolysaccharides from gastric enterohepatic spp. not previously characterized. Materials methods. Purified four ( H. , felis bizzozeronii mustelae ) hepaticus bilis ‘ sp. flexispira ’ pullorum were structurally characterized using electrophoretic, serological chemical Results. Structural insights into...

Helicobacter pylori colonises the gastric mucosa of humans. The majority organisms live in mucus. These are an important reservoir for infection underlying epithelium. Cell culture models H. do not normally possess a mucus layer. interaction with TFF1, member trefoil factor family found mucin, is mediated by lipopolysaccharide. To test hypothesis that TFF1 promotes colonization we characterised secreting cell line, HT29-MTX-E12. An isogenic mutant truncated core oligosaccharides was produced...

Cryptosporidiosis in humans is caused by the zoonotic pathogen Cryptosporidium parvum and anthroponotic hominis. To what extent recently recognized C. hominis species differs from unknown. In this study we compared mechanisms of invasion using a primary cell model infection. Cultured bovine human epithelial intestinal cells were infected with or The effects carbohydrate lectin galactose-N-acetylgalactosamine (Gal/GalNAc) inhibitors cytoskeletal function signal transduction on entry parasites...

The host cell environment can alter bacterial pathogenicity. We employed a combination of cellular and molecular techniques to study the expression Campylobacter jejuni polysaccharides cocultured with HCT-8 epithelial cells. After two passages, amount membrane-bound high-molecular-weight polysaccharide was considerably reduced. Microarray profiling confirmed significant downregulation capsular (CPS) locus genes. Experiments using conditioned media showed that sugar depletion occurred only...

ABSTRACT Isogenic flagellum-negative mutants of Helicobacter pylori and mustelae were screened for their ability to adhere primary human ferret gastric epithelial cells, respectively. We also evaluated the adherence an H. strain with a mutation in flbA gene, homologue flbF/lcrD family genes known be involved regulation flagellar biosynthesis. deficient production FlaA or FlaB both showed no reduction cells compared wild-type parental strains. However, mutant was significantly reduced strain....

The trefoil peptides (TFF1, TFF2 and TFF3) are a family of small highly conserved proteins that play an essential role in epithelial regeneration within the gastrointestinal tract, where they mainly expressed. TFF1 expression is strongly induced after mucosal injury it has been proposed tff1 functions as gastric tumor suppressor gene. Several studies confirm frequently lost cancer because deletions, mutations or methylation promoter. Infection by Helicobacter pylori (H. pylori) results...