Escherichia coli verotoxin (also known as Shiga-like toxin) has been implicated in the aetiology of hemolytic uremic syndrome and hemorrhagic colitis. The glycolipid binding specificity purified from E. H30 cloned bacteriophage H19B examined. Verotoxin both sources binds specifically to globotriosyl ceramide containing carbohydrate sequence galactose alpha 1-4galactose beta 1-4glucose-ceramide. Removal terminal or substitution with N-acetylgalactosamine 1-3 linkage deletes toxin activity. A...

The influenza virus (IFV) acquires its envelope by budding from host cell plasma membranes. Using quantitative shotgun mass spectrometry, we determined the lipidomes of Madin–Darby canine kidney cell, apical membrane, and IFV it. We found membrane to be enriched in sphingolipids (SPs) cholesterol, whereas glycerophospholipids were reduced, storage lipids depleted compared with whole-cell exhibited a further enrichment SPs cholesterol donor at expense phosphatidylcholines. Our data are...

This study addresses the basis for regional microvascular susceptibility to bacterial toxins implicated in hemolytic uremic syndrome. The results indicate a relationship between degree of Shiga toxin sensitivity human endothelial cells from different sources and amount globotriaosylceramide (Gb3) glycosphingolipid receptor expressed by these cells. Cell viability protein synthesis renal were reduced 50% 1 pM toxin, while umbilical vein not affected > nM toxin. Similarly, basal levels Gb3...

In HeLa cells, Shiga toxin B-subunit is transported from the plasma membrane to endoplasmic reticulum, via early endosomes and Golgi apparatus, circumventing late endocytic pathway. We describe here that in cells derived human monocytes, i.e., macrophages dendritic was internalized a receptor-dependent manner, but retrograde transport biosynthetic/secretory pathway did not occur part of protein degraded lysosomes. These differences correlated with observation associated Triton...

Infection with verotoxin producing Escherichia coli has been strongly implicated in the etiology of hemolytic uremic syndrome (HUS). We have previously shown that this toxin specifically binds to a glycolipid receptor-globotriosyl ceramide (Gb3). therefore quantitated level by HPLC human renal cortex and medulla as function age. also measured binding Gb3 isolated from each tissue sample. was major component fraction all samples analyzed. The levels were found be higher than medulla,...

Verotoxins (VT) are a family of Escherichia coli-derived toxins which have been associated with hemolytic uremic syndrome, the leading cause acute pediatric renal failure, and hemorrhagic colitis.Verotoxins (VT1 VT2c) both show terminal galal4gal-dependent binding to globotriaosylceramide (GalalAGal/314Glc-Cer; Gb,), yet V T 2 c shows thousandfold lower specific cytotoxic activity in vitro.Our previous studies shown this discrepancy is function receptor B subunit that VTl/Gb, lipid matrix...

The pH within individual organelles of the secretory pathway is believed to be an important determinant their biosynthetic activity. However, little known about determinants and regulation in organelles, which cannot readily accessed by [H + ]-sensitive probes. We devised a procedure for dynamic, noninvasive measurement lumen endoplasmic reticulum intact mammalian cells. A recombinant form B subunit Shiga toxin, previously modified include carboxyl-terminal KDEL sequence pH-sensitive...

The pig edema disease toxin has been shown by a tlc glycolipid binding assay to bind specifically globotetraosylceramide (Gb4, GalNAcβ1–3Galα1–4Galβ1–4GlcCer.). Binding was reduced for globotriosylceramide (Gb3, Galα1–4Galβ1–4GlcCer) and more markedly the Forssman antigen (GalNAcα1–3GalNAcβ1–3Galα1–4Galβ1–4GlcCer). Paragloboside, blood group A glycolipids, glycolipids terminating in Gal NAcβ1–4Gal-, which globoside present as an internal sequence did not toxin. Isogloboside...

Gastrointestinal infection with verotoxin-producing <i>Escherichia coli </i>(VTEC) has been strongly implicated in the etiology of hemolytic uremic syndrome (HUS), leading cause pediatric acute renal failure. The binding fluorescein-conjugated VT1 overlaid on to frozen human sections examined. Sections from biopsies infants aged < 2 years were compared those adult autopsies. VT primarily stained distal convoluted tubules, particularly adjacent glomeruli, and collecting ducts. VT-binding was...

Summary Pili are one of the adhesins Pseudomonas aeruginosa that mediate adherence to epithelial cell‐surface receptors. The pili P. strains PAK and PAO were examined found bind gangliotetraosyl ceramide (asialo‐GM 1 ) and, a lesser extend, ll 3 N ‐acetylneuraminosylgangliotetraosyl (GM in solid‐phase binding assays. Asialo‐GM , but not GM inhibited both immobilized asialo‐GM on microtitre plate. competitively suggesting presence structurally similar receptor‐binding domain pilus types....

The B subunit of verotoxin (VT1B) from enterohemorrhagic Escherichia coli is responsible for the attachment holotoxin to cell surface, by binding glycolipid, globotriaosyl ceramide. After receptor-mediated endocytosis, toxin targeted Golgi complex a process retrograde transport. We took advantage this unique property VT1B measure pH in intact live cells. Purified recombinant was labeled with either rhodamine or fluorescein subcellular localization confocal microscopy. 1 h at 37 degrees C,...

The gastric pathogen helicobacter pylori is one of a number bacteria which bind specifically to gangliotetraosylceramide, gangliotriaosylceramide, and phosphatidylethanolamine in vitro at neutral pH. Since this organism encounters an acid pH during initial infection the stomach, we have monitored effect on receptor binding specificity found induction specific sulfoglycolipids (sulfatide) following brief treatment low We previously shown that heat shock proteins (hsps) sulfatide, suspicion...

Verocytotoxins comprise a family of closely related subunit proteins. Two members this group, VT1 and the immunologically distinct VT2, have been found to share similar physical properties, yet several differences in their biological activities noted. The subunits these toxins were separated using urea isolated by high performance liquid chromatography gel filtration. Reconstituted VT2 as well VT1-A:VT2-B VT2-A:VT1-B hybrid then prepared. B was determine cell culture specificity, cytotoxic...

We have previously shown that Helicobacter pylori specifically binds to a glycerolipid species preferentially found in the antrum of human stomach. now show by high-pressure liquid chromatographic analysis this is form phosphatidylethanolamine and H. bona fide as detected thin-layer chromatogram overlay procedure. Considerable variation binding from different sources was observed, however, suggesting importance nature long-chain hydrophobic moiety. A similar specificity exoenzyme S...

Globotriaosylceramide [(Gal alpha 1-4Gal beta 1-4Glc-ceramide (Gb3)] was separated from human kidney, and the fatty acid composition determined. Semisynthetic Gb3 molecular species of corresponding chain length were prepared compared for verotoxin (VT) binding affinity by TLC overlay, a quantitative assay performed in presence auxiliary lipids. Our results indicate that, within natural range, has little effect on but that containing different acids can interact to provide higher toxin...

Verotoxin 1 is an Escherichia coli-derived subunit toxin that specifically binds to the glycolipid globotriosylceramide and cytotoxic for cells contain this plasma membrane glycolipid. Glycolipid incorporation experiments have now been performed using human lymphoid of B lineage lack receptor, conclusively demonstrate alone a functional receptor toxin. Globotriosylceramide incorporated into toxin-resistant provides intracellular access verotoxin by receptor-mediated endocytosis. Protein...

The pentameric B subunit of verotoxin (VT) mediates the attachment to cell surface globotriaosyl ceramide (Gb3) facilitate receptor-mediated endocytosis toxin. In highly toxin-sensitive tumor cells, holotoxin and VT1 is targeted intracellularly elements endoplasmic reticulum (ER)/nuclear membrane. less sensitive toxin components Golgi apparatus. We have studied two systems: induced VT hypersensitivity human astrocytoma lines cultured in presence sodium butyrate (compared propionate...

Development of hemolytic uremic syndrome (HUS) after infection by Shigella dysenteriae 1 or enterohemorrhagic Escherichia coli has been associated with the production Shiga toxins (verotoxins). The putative target in HUS is renal microvascular endothelium. This report shows that preincubation human umbilical vein endothelial cells (HUVEC) interleukin-1 beta (IL-1 beta) enhances cytotoxic potency toxin toward HUVEC. A HUVEC IL-1 required for sensitization to toxin. Sensitization dose...