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  • virulence
  • Here, we will characterize the basic mechanisms of cell binding by AC toxin and show that these mechanisms affect the function of the toxin and determine its role as a virulence factor. (grantome.com)
  • Toxin-antitoxin genes are often transferred through horizontal gene transfer and are associated with pathogenic bacteria, having been found on plasmids conferring antibiotic resistance and virulence. (wikipedia.org)
  • host
  • AC toxin intoxicates host cells by binding to the cell membrane and translocating its catalytic domain across the lipid-bilayer, resulting in unregulated generation of intracellular cAMP. (grantome.com)
  • In evolutionary terms, toxin-antitoxin systems can be considered selfish DNA in that the purpose of the systems are to replicate, regardless of whether they benefit the host organism or not. (wikipedia.org)
  • for example, chromosomal toxin-antitoxin systems could have evolved to prevent the inheritance of large deletions of the host genome. (wikipedia.org)
  • It has been theorised that toxin-antitoxin loci serve only to maintain their own DNA, at the expense of the host organism. (wikipedia.org)
  • Thus, the toxin-antitoxin system confers an advantage to the host DNA by eliminating competing plasmids in cell progeny. (wikipedia.org)
  • explain
  • The determinants of toxin binding and function may explain a novel finding: cells of an epithelial monolayer are insensitive to intoxication by AC toxin applied to the apical surface, surprising because the toxin can intoxicate all cell types so far tested, and important because the bacterium first encounters these cells upon infection. (grantome.com)
  • This does not, however, explain the presence of toxin-antitoxin systems on chromosomes. (wikipedia.org)
  • however
  • The magnitude of intoxication correlates with the relative surface expression of the (32 integrin, CD11b/CD18, a receptor expressed most abundantly on neutrophils and macrophages;however, the relationship between AC toxin and CD11b/CD18 is not well defined. (grantome.com)
  • cell
  • Prevention of translocation by an antibody to the catalytic domain or by certain mutations will enhance the other major function of the toxin, formation of oligomeric pores which cause lysis of erythrocytes and contribute to non-apoptotic cell death of macrophages. (grantome.com)
  • Chromosomal toxin-antitoxin systems also exist, some of which perform cell functions such as responding to stresses, causing cell cycle arrest and bringing about programmed cell death. (wikipedia.org)
  • Toxin-antitoxin systems have several biotechnological applications, such as a method of maintaining plasmids in cell lines, targets for antibiotics, and as positive selection vectors. (wikipedia.org)
  • MazEF, a toxin-antitoxin locus found in E. coli and other bacteria, induces programmed cell death in response to starvation, specifically a lack of amino acids. (wikipedia.org)
  • formation
  • Our preliminary data show that CD11b/CD18 does not simply increase sensitivity of cells to intoxication, but, when high concentrations of toxin are applied to cells, actually limits intoxication while possibly enhancing oligomer formation. (grantome.com)
  • These studies will shed light upon the mechanism of pore formation by bacterial toxins, and the pathogenesis of disease caused by all Bordetellae. (grantome.com)
  • A homologue of mazF toxin called mazF-mx is essential for fruiting body formation in Myxococcus xanthus. (wikipedia.org)
  • peptide
  • Using a MALDI-MS based assay, the kinetic parameters for peptide glucosylation using the C. difficile toxin B glycosyltransferase domain were determined. (rsc.org)
  • 15 Inspired by this finding, we speculated that a short peptide containing the consensus sequence may be an acceptable substrate for the toxin B GTD. (rsc.org)
  • It was discovered in Escherichia coli strain K-12 in a long direct repeat (LDR) named LDR-D. This locus encodes two products: a 35 amino acid peptide toxin (ldrD) and a 60 nucleotide RNA antitoxin. (wikipedia.org)
  • binds
  • Just visible protruding from the membrane surface under the toxin which has landed are five copies of the saccharide moitie of ganglioside GM1, to which the toxin binds. (washington.edu)
  • After their B subunit binds to receptors on the cell surface, the toxin is enveloped by the cell and transported inside either through clathrin-dependent endocytosis or clathrin-independent endocytosis. (wikipedia.org)
  • The R domain binds to a cell surface receptor, permitting the toxin to enter the cell by receptor-mediated endocytosis. (wikipedia.org)
  • The toxin binds to heparin-binding epidermal growth factor precursor (HB-EGF). (wikipedia.org)
  • receptors
  • His team also proposes a new model, explains Aktories: "Our findings indicate that two receptors are involved in the effect of the other sugar-carrying clostridial toxins. (infectioncontroltoday.com)
  • Our discovery will also provide new impetus for researchers to identify further toxin receptors," Aktories hopes. (infectioncontroltoday.com)
  • Since many of those toxins are well studied concerning molecular mechanisms, cellular receptors, uptake routes, and structures, they are now widely used to analyze or to influence specific signaling pathways of mammalian cells. (mdpi.com)
  • Proteins need specific receptors on cells in order to form the Cry proteins and become toxic, which is why the toxins are specific for the order Lepidoptera. (wikipedia.org)
  • In both TSS (caused by S. aureus) and TSLS (caused by S. pyogenes), disease progression stems from a superantigen toxin that allows the nonspecific binding of MHC II with T-cell receptors, resulting in polyclonal T-cell activation. (wikipedia.org)
  • Amino
  • A thorough proteomic study of toxin A/B substrates revealed that the amino acid sequences flanking the glycosylation site are similar among GTPase substrates. (rsc.org)
  • The amino N-terminal domain contains the active site, responsible for the glucosylating activity of the toxin. (wikipedia.org)
  • Examples of this type include the 26-amino-acid δ-toxins from Straphylococcus aureus, S. haemolyticus and S. lugdunensis, Bacillus subtilis toxin and the cytolysin from Pseudomonas aeruginosa. (wikipedia.org)
  • Bacillus
  • The inserted gene is from the Bacillus thuringiensis which produces the Bt toxin that is poisonous to insects in the Lepidoptera order (butterflies and moths), including the European Corn Borer. (wikipedia.org)
  • Vibrio
  • Representative cytolysins of this type of include C. perfringens α-toxin (phospholipase C), S. aureus β-toxin (shingomyelinase C) and Vibrio damsela (phospholipase D). Farlane et al. (wikipedia.org)
  • cytoplasm
  • This approach will enable glycoproteins to be produced in the bacterial cytoplasm with endogenous nucleotide sugar donors. (rsc.org)
  • vaccine
  • When this approach is combined with the intermediates of bacterial O -antigen biosynthesis the resulting conjugates are valuable as potential anti-bacterial vaccine components. (rsc.org)
  • Rappuoli led Chiron Corporation's development of adjuvanted influenza vaccines, MENJUGATE(R) conjugate vaccine against meningococcal-C disease and the first recombinant bacterial vaccine against pertussis. (wikipedia.org)
  • gene
  • Effects on non-target organisms (i.e. those outside the group of Lepidoptera) indicates that the Cry1Ab toxin has less specific modes of toxicity than previously assumed, or that the transgene insertion may cause unintended effects (e.g. changes in gene expression) in the plant. (wikipedia.org)
  • clarification needed] In 1951, Freeman found that the toxin gene was not encoded on the bacterial chromosome, but by a lysogenic phage infecting all toxigenic strains. (wikipedia.org)
  • The other process is irreversible, using toxins to completely change the target GTPase and shut down or override gene expression. (wikipedia.org)
  • substrates
  • In most cases, these toxins are extremely effective enzymes with high specificity towards their cellular substrates, which are often central signaling molecules. (mdpi.com)
  • Both TcdA and TcdB use this highly conserved N-terminal region (74% homology between both toxins) to alter identical substrates. (wikipedia.org)
  • disease
  • Here, we review the development of immunotoxins and targeted toxins for the treatment of a disease that is still hard to treat: cancer. (mdpi.com)
  • cellular
  • The toxins force their way into host cells and deactivate signaling molecules by attaching a sugar molecule to these cellular switches. (infectioncontroltoday.com)
  • A few molecules, at least of some toxins, are sufficient to change the cellular morphology and function of a cell or even kill a cell. (mdpi.com)
  • One method of study has been to examine the effect of toxins on normal cellular processes such as the active transport of sodium and oxidative metabolism. (annals.org)
  • Most current antibiotics focus on destroying the cellular envelope that encompasses a bacterial cell, preventing it from replicating," says Jensen. (caltech.edu)
  • The toxin acts by modifying host cell GTPase proteins by glucosylation, leading to changes in cellular activities. (wikipedia.org)
  • Potential applications of toxin research include combating microbial virulence, the development of novel anticancer drugs and other medicines, and the use of toxins as tools in neurobiology and cellular biology. (wikipedia.org)
  • subunit
  • As with many other bacterial toxins the catalytic activity resides in the `A' fragment, in this case a separate subunit, while receptor binding and delivery of the toxin to the target cell is mediated by a separate `B' fragment, in this case a pentamer. (washington.edu)
  • The A subunit of an AB5 toxin is the portion responsible for catalysis of specific targets. (wikipedia.org)
  • coli
  • It is distinct from the toxin found in E. coli strain 0157, responsible for the recent outbreak of food poisoning tied to spinach. (phys.org)
  • 12,13 The N-terminal glucosyltransferase domain of toxin B is a family 44 glycosyltransferase (http://www.cazy.org) which uses UDP-glucose as the donor sugar and can be overexpressed as active soluble enzyme in E. coli. (rsc.org)
  • catalytic
  • The class of AB 5 toxins may be subdivided into families based on sequence homology and catalytic activity. (washington.edu)
  • This unique ability can be repurposed to deliver therapeutic proteins, instead of the catalytic domain of the toxin. (wikipedia.org)
  • cell
  • The toxins bind to surface molecules and creep into the body cell, where they lead to cell death. (infectioncontroltoday.com)
  • In order to prevent the toxin from entering the cell, it is necessary to find the receptor that serves as the gatekeeper. (infectioncontroltoday.com)
  • How does the toxin recognize and bind to the cell surface? (washington.edu)
  • It provides both a better understanding of the attachment of the toxin to the cell (see figure at top of page) and a starting point for the structure-based design of receptor binding inhibitors. (washington.edu)
  • Developing new antibiotics that target different aspects of the bacterial cell, such as the type IV secretion system, would enable us to block infections in additional ways. (caltech.edu)
  • Some symptoms caused by this toxin are a decrease in platelet count in the blood or thrombocytopenia, an increase in white blood cell count or leukocytosis, and renal cell damage. (wikipedia.org)
  • These bacterial strains present a thickening of the cell wall, which is believed to reduce the ability of vancomycin to diffuse into the division septum of the cell required for effective vancomycin treatment. (wikipedia.org)
  • glucosylation
  • Toxin B realizes its cytotoxic effects by inactivating small GTPases through α-glucosylation of conserved active-site threonine residues. (rsc.org)
  • The glucosylation reaction was evaluated by incubation of the peptides with toxin B GTD and excess UDP-glucose ( Fig. 2 ). (rsc.org)
  • receptor
  • In cooperation with colleagues from Düsseldorf, the USA, and the Netherlands, the researchers from Freiburg have now identified a receptor for a clostridial toxin of this type for the first time ever. (infectioncontroltoday.com)
  • organisms
  • This is despite the fact that several of the meta-analyses reviewed actually indicate specific negative effects from Cry1Ab toxin on non-target organisms, although when compared to spraying with broad-spectrum pesticides, the negative effects on non-target organisms from Cry-toxins were lower. (wikipedia.org)
  • Virulence Factors basically Include the Antigenic Structure and The Toxins produced by the organisms. (wikipedia.org)
  • symptoms
  • Some symptoms of this toxin include chronic and widespread watery diarrhea and dehydration that, in some cases, leads to death. (wikipedia.org)
  • infections
  • A toxin that can make bacterial infections turn deadly is also found in higher plants, researchers at UC Davis, the Marine Biology Laboratory at Woods Hole, Mass. and the University of Nebraska have found. (phys.org)
  • proteins
  • TcdA acts preferentially on the GDP-bound form of the GTPase proteins since this configuration exposes the threonine residue that is glucosylated by the toxin. (wikipedia.org)
  • virulence
  • Here, we will characterize the basic mechanisms of cell binding by AC toxin and show that these mechanisms affect the function of the toxin and determine its role as a virulence factor. (grantome.com)
  • Toxin-antitoxin genes are often transferred through horizontal gene transfer and are associated with pathogenic bacteria, having been found on plasmids conferring antibiotic resistance and virulence. (wikipedia.org)
  • host
  • AC toxin intoxicates host cells by binding to the cell membrane and translocating its catalytic domain across the lipid-bilayer, resulting in unregulated generation of intracellular cAMP. (grantome.com)
  • In evolutionary terms, toxin-antitoxin systems can be considered selfish DNA in that the purpose of the systems are to replicate, regardless of whether they benefit the host organism or not. (wikipedia.org)
  • for example, chromosomal toxin-antitoxin systems could have evolved to prevent the inheritance of large deletions of the host genome. (wikipedia.org)
  • It has been theorised that toxin-antitoxin loci serve only to maintain their own DNA, at the expense of the host organism. (wikipedia.org)
  • Thus, the toxin-antitoxin system confers an advantage to the host DNA by eliminating competing plasmids in cell progeny. (wikipedia.org)
  • explain
  • The determinants of toxin binding and function may explain a novel finding: cells of an epithelial monolayer are insensitive to intoxication by AC toxin applied to the apical surface, surprising because the toxin can intoxicate all cell types so far tested, and important because the bacterium first encounters these cells upon infection. (grantome.com)
  • This does not, however, explain the presence of toxin-antitoxin systems on chromosomes. (wikipedia.org)
  • however
  • The magnitude of intoxication correlates with the relative surface expression of the (32 integrin, CD11b/CD18, a receptor expressed most abundantly on neutrophils and macrophages;however, the relationship between AC toxin and CD11b/CD18 is not well defined. (grantome.com)
  • cell
  • Prevention of translocation by an antibody to the catalytic domain or by certain mutations will enhance the other major function of the toxin, formation of oligomeric pores which cause lysis of erythrocytes and contribute to non-apoptotic cell death of macrophages. (grantome.com)
  • Chromosomal toxin-antitoxin systems also exist, some of which perform cell functions such as responding to stresses, causing cell cycle arrest and bringing about programmed cell death. (wikipedia.org)
  • Toxin-antitoxin systems have several biotechnological applications, such as a method of maintaining plasmids in cell lines, targets for antibiotics, and as positive selection vectors. (wikipedia.org)
  • MazEF, a toxin-antitoxin locus found in E. coli and other bacteria, induces programmed cell death in response to starvation, specifically a lack of amino acids. (wikipedia.org)
  • formation
  • Our preliminary data show that CD11b/CD18 does not simply increase sensitivity of cells to intoxication, but, when high concentrations of toxin are applied to cells, actually limits intoxication while possibly enhancing oligomer formation. (grantome.com)
  • These studies will shed light upon the mechanism of pore formation by bacterial toxins, and the pathogenesis of disease caused by all Bordetellae. (grantome.com)
  • A homologue of mazF toxin called mazF-mx is essential for fruiting body formation in Myxococcus xanthus. (wikipedia.org)
  • bacteria
  • In that same article, I discuss that beyond the chemical toxins mold produces (mycotoxins) to lay claim on that piece of decaying matter, there are a whole host of other inflammagens that mold and bacteria emit that make a person with CIRS sick - Beta Glucans, Volatile Organic Compounds (VOC), Lipopolysaccharides (LPS), etc. (biotoxinjourney.com)
  • When the mosquito larvae ingest the bacteria, crystallized toxins are produced that destroy the digestive tract, resulting in death. (wikipedia.org)
  • In the next 24 hours, this layer allows the process of bacterial adhesion to occur, with both diatoms and bacteria (e.g. vibrio alginolyticus, pseudomonas putrefaciens) attaching, initiating the formation of a biofilm. (wikipedia.org)
  • diseases
  • At this point, though the drug had shown success in treating numerous bacterial diseases, it was still so difficult to produce and so dilute that it was not feasible to produce quantities large enough for mass production, so an effort was begun to find a strain of Penicillium with a higher rate of production of penicillin. (wikipedia.org)
  • species
  • Such wetland benefits include flood control downstream, biodiversity (by providing habitat for many rare as well as common species), and water cleansing, both by the breakdown of toxins such as pesticides and the retention of silt by beaver dams. (wikipedia.org)
  • cells
  • Jan. 7, 2016- Inducing "tolerance" to bacterial toxins in the endothelial cells that line blood vessels may offer a new approach for preventing the negative consequences of sepsis. (vanderbilt.edu)
  • Stimulus-triggered acquisition of pluripotency (also known as STAP) was a proposed method of generating pluripotent stem cells by subjecting ordinary cells to certain types of stress, such as the application of a bacterial toxin, submersion in a weak acid, or physical trauma. (wikipedia.org)
  • WC-rBS (marketed as "Dukoral") is a monovalent inactivated vaccine containing killed whole cells of V. cholerae O1 plus additional recombinant cholera toxin B subunit. (wikipedia.org)
  • The activity of these toxins is most easily observed with assays involving the lysis of red blood cells (erythrocytes). (wikipedia.org)
  • liver
  • The most important factor in liver disease is to prevent the underlying causes by having your puppy properly vaccinated, keeping your pet away from potential toxins, and using therapeutic drugs according to your veterinarian's instructions. (blogspot.com)
  • And finally, I'll finish by looking at improving the three liver detoxification Phases that are responsible for removing toxins of all sorts including Biotoxins. (biotoxinjourney.com)
  • Given that toxins can upset good gastrointestinal (GI) flora, looking at the three Phases of liver detoxification also ties into the general theme of gut health. (biotoxinjourney.com)
  • effects
  • Over 191 studies on how polychlorinated biphenyls (PCBs) affect thyroid function, and 185 studies on the effects of dioxin and thyroid function have been published since the identification of these toxins in the late 1960s. (ndnr.com)
  • No attempt has been made to look at the additive effects of low doses of multiple toxins, or to clarify whether effects are additive, synergistic, or antagonistic. (ndnr.com)
  • study
  • Cases of the debilitating childhood disease in Japan are likely caused by toxins that float in from China's farmlands, a study finds. (the-scientist.com)