Toxic substances formed in or elaborated by bacteria; they are usually proteins with high molecular weight and antigenicity; some are used as antibiotics and some to skin test for the presence of or susceptibility to certain diseases.
An ENTEROTOXIN from VIBRIO CHOLERAE. It consists of two major protomers, the heavy (H) or A subunit and the B protomer which consists of 5 light (L) or B subunits. The catalytic A subunit is proteolytically cleaved into fragments A1 and A2. The A1 fragment is a MONO(ADP-RIBOSE) TRANSFERASE. The B protomer binds cholera toxin to intestinal epithelial cells, and facilitates the uptake of the A1 fragment. The A1 catalyzed transfer of ADP-RIBOSE to the alpha subunits of heterotrimeric G PROTEINS activates the production of CYCLIC AMP. Increased levels of cyclic AMP are thought to modulate release of fluid and electrolytes from intestinal crypt cells.
Enzymes that transfer the ADP-RIBOSE group of NAD or NADP to proteins or other small molecules. Transfer of ADP-ribose to water (i.e., hydrolysis) is catalyzed by the NADASES. The mono(ADP-ribose)transferases transfer a single ADP-ribose. POLY(ADP-RIBOSE) POLYMERASES transfer multiple units of ADP-ribose to protein targets, building POLY ADENOSINE DIPHOSPHATE RIBOSE in linear or branched chains.
Exotoxins produced by certain strains of streptococci, particularly those of group A (STREPTOCOCCUS PYOGENES), that cause HEMOLYSIS.
Substances that are toxic to cells; they may be involved in immunity or may be contained in venoms. These are distinguished from CYTOSTATIC AGENTS in degree of effect. Some of them are used as CYTOTOXIC ANTIBIOTICS. The mechanism of action of many of these are as ALKYLATING AGENTS or MITOSIS MODULATORS.
A potent mycotoxin produced in feedstuffs by several species of the genus FUSARIUM. It elicits a severe inflammatory reaction in animals and has teratogenic effects.
Substances that are toxic to the intestinal tract causing vomiting, diarrhea, etc.; most common enterotoxins are produced by bacteria.
Proteins from BACTERIA and FUNGI that are soluble enough to be secreted to target ERYTHROCYTES and insert into the membrane to form beta-barrel pores. Biosynthesis may be regulated by HEMOLYSIN FACTORS.
Specific, characterizable, poisonous chemicals, often PROTEINS, with specific biological properties, including immunogenicity, produced by microbes, higher plants (PLANTS, TOXIC), or ANIMALS.
Toxins produced, especially by bacterial or fungal cells, and released into the culture medium or environment.
Proteins found in any species of bacterium.
Protein synthesized by CLOSTRIDIUM TETANI as a single chain of ~150 kDa with 35% sequence identity to BOTULINUM TOXIN that is cleaved to a light and a heavy chain that are linked by a single disulfide bond. Tetanolysin is the hemolytic and tetanospasmin is the neurotoxic principle. The toxin causes disruption of the inhibitory mechanisms of the CNS, thus permitting uncontrolled nervous activity, leading to fatal CONVULSIONS.
An ester formed between the aldehydic carbon of RIBOSE and the terminal phosphate of ADENOSINE DIPHOSPHATE. It is produced by the hydrolysis of nicotinamide-adenine dinucleotide (NAD) by a variety of enzymes, some of which transfer an ADP-ribosyl group to target proteins.
An ADP-ribosylating polypeptide produced by CORYNEBACTERIUM DIPHTHERIAE that causes the signs and symptoms of DIPHTHERIA. It can be broken into two unequal domains: the smaller, catalytic A domain is the lethal moiety and contains MONO(ADP-RIBOSE) TRANSFERASES which transfers ADP RIBOSE to PEPTIDE ELONGATION FACTOR 2 thereby inhibiting protein synthesis; and the larger B domain that is needed for entry into cells.
Antisera from immunized animals that is purified and used as a passive immunizing agent against specific BACTERIAL TOXINS.
One of the virulence factors produced by virulent BORDETELLA organisms. It is a bifunctional protein with both ADENYLYL CYCLASES and hemolysin components.
Proteins obtained from ESCHERICHIA COLI.
A serotype of botulinum toxins that has specificity for cleavage of SYNAPTOSOMAL-ASSOCIATED PROTEIN 25.
Toxic or poisonous substances elaborated by marine flora or fauna. They include also specific, characterized poisons or toxins for which there is no more specific heading, like those from poisonous FISHES.
Toxic proteins produced from the species CLOSTRIDIUM BOTULINUM. The toxins are synthesized as a single peptide chain which is processed into a mature protein consisting of a heavy chain and light chain joined via a disulfide bond. The botulinum toxin light chain is a zinc-dependent protease which is released from the heavy chain upon ENDOCYTOSIS into PRESYNAPTIC NERVE ENDINGS. Once inside the cell the botulinum toxin light chain cleaves specific SNARE proteins which are essential for secretion of ACETYLCHOLINE by SYNAPTIC VESICLES. This inhibition of acetylcholine release results in muscular PARALYSIS.
Those components of an organism that determine its capacity to cause disease but are not required for its viability per se. Two classes have been characterized: TOXINS, BIOLOGICAL and surface adhesion molecules that effect the ability of the microorganism to invade and colonize a host. (From Davis et al., Microbiology, 4th ed. p486)
A species of bacteria that causes ANTHRAX in humans and animals.
A large family of MONOMERIC GTP-BINDING PROTEINS that are involved in regulation of actin organization, gene expression and cell cycle progression. This enzyme was formerly listed as EC
A class of toxins that inhibit protein synthesis by blocking the interaction of ribosomal RNA; (RNA, RIBOSOMAL) with PEPTIDE ELONGATION FACTORS. They include SHIGA TOXIN which is produced by SHIGELLA DYSENTERIAE and a variety of shiga-like toxins that are produced by pathologic strains of ESCHERICHIA COLI such as ESCHERICHIA COLI O157.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
A proprotein convertase with specificity for the proproteins of PROALBUMIN; COMPLEMENT 3C; and VON WILLEBRAND FACTOR. It has specificity for cleavage near paired ARGININE residues that are separated by two amino acids.
Bacteriocins elaborated by strains of Escherichia coli and related species. They are proteins or protein-lipopolysaccharide complexes lethal to other strains of the same species.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
A toxin produced by certain pathogenic strains of ESCHERICHIA COLI such as ESCHERICHIA COLI O157. It shares 50-60% homology with SHIGA TOXIN and SHIGA TOXIN 1.
One of the virulence factors produced by BORDETELLA PERTUSSIS. It is a multimeric protein composed of five subunits S1 - S5. S1 contains mono ADPribose transferase activity.
A toxin produced by certain pathogenic strains of ESCHERICHIA COLI such as ESCHERICHIA COLI O157. It is closely related to SHIGA TOXIN produced by SHIGELLA DYSENTERIAE.
Proteins secreted from an organism which form membrane-spanning pores in target cells to destroy them. This is in contrast to PORINS and MEMBRANE TRANSPORT PROTEINS that function within the synthesizing organism and COMPLEMENT immune proteins. These pore forming cytotoxic proteins are a form of primitive cellular defense which are also found in human LYMPHOCYTES.
Microbial antigens that have in common an extremely potent activating effect on T-cells that bear a specific variable region. Superantigens cross-link the variable region with class II MHC proteins regardless of the peptide binding in the T-cell receptor's pocket. The result is a transient expansion and subsequent death and anergy of the T-cells with the appropriate variable regions.
Semisynthetic conjugates of various toxic molecules, including RADIOACTIVE ISOTOPES and bacterial or plant toxins, with specific immune substances such as IMMUNOGLOBULINS; MONOCLONAL ANTIBODIES; and ANTIGENS. The antitumor or antiviral immune substance carries the toxin to the tumor or infected cell where the toxin exerts its poisonous effect.
The most common etiologic agent of GAS GANGRENE. It is differentiable into several distinct types based on the distribution of twelve different toxins.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
A set of BACTERIAL ADHESINS and TOXINS, BIOLOGICAL produced by BORDETELLA organisms that determine the pathogenesis of BORDETELLA INFECTIONS, such as WHOOPING COUGH. They include filamentous hemagglutinin; FIMBRIAE PROTEINS; pertactin; PERTUSSIS TOXIN; ADENYLATE CYCLASE TOXIN; dermonecrotic toxin; tracheal cytotoxin; Bordetella LIPOPOLYSACCHARIDES; and tracheal colonization factor.
A toxin produced by SHIGELLA DYSENTERIAE. It is the prototype of class of toxins that inhibit protein synthesis by blocking the interaction of ribosomal RNA; (RNA, RIBOSOMAL) with PEPTIDE ELONGATION FACTORS.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Substances elaborated by bacteria that have antigenic activity.
Established cell cultures that have the potential to propagate indefinitely.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.
Regulatory proteins that act as molecular switches. They control a wide range of biological processes including: receptor signaling, intracellular signal transduction pathways, and protein synthesis. Their activity is regulated by factors that control their ability to bind to and hydrolyze GTP to GDP. EC 3.6.1.-.
A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)
The rate dynamics in chemical or physical systems.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.
The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Proteins prepared by recombinant DNA technology.
The relationship between the dose of an administered drug and the response of the organism to the drug.
Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.
A RHO GTP-BINDING PROTEIN involved in regulating signal transduction pathways that control assembly of focal adhesions and actin stress fibers. This enzyme was formerly listed as EC
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.
One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
Venoms from animals of the order Scorpionida of the class Arachnida. They contain neuro- and hemotoxins, enzymes, and various other factors that may release acetylcholine and catecholamines from nerve endings. Of the several protein toxins that have been characterized, most are immunogenic.
Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.
A common inhabitant of the colon flora in human infants and sometimes in adults. It produces a toxin that causes pseudomembranous enterocolitis (ENTEROCOLITIS, PSEUDOMEMBRANOUS) in patients receiving antibiotic therapy.
A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.
Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.
Toxic compounds produced by FUNGI.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)
A species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. aeruginosa is a major agent of nosocomial infection.
The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Drugs used for their actions on skeletal muscle. Included are agents that act directly on skeletal muscle, those that alter neuromuscular transmission (NEUROMUSCULAR BLOCKING AGENTS), and drugs that act centrally as skeletal muscle relaxants (MUSCLE RELAXANTS, CENTRAL). Drugs used in the treatment of movement disorders are ANTI-DYSKINESIA AGENTS.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.
Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Arthropods of the order Scorpiones, of which 1500 to 2000 species have been described. The most common live in tropical or subtropical areas. They are nocturnal and feed principally on insects and other arthropods. They are large arachnids but do not attack man spontaneously. They have a venomous sting. Their medical significance varies considerably and is dependent on their habits and venom potency rather than on their size. At most, the sting is equivalent to that of a hornet but certain species possess a highly toxic venom potentially fatal to humans. (From Dorland, 27th ed; Smith, Insects and Other Arthropods of Medical Importance, 1973, p417; Barnes, Invertebrate Zoology, 5th ed, p503)
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A protein phytotoxin from the seeds of Ricinus communis, the castor oil plant. It agglutinates cells, is proteolytic, and causes lethal inflammation and hemorrhage if taken internally.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
Elements of limited time intervals, contributing to particular results or situations.
Toxic substances from microorganisms, plants or animals that interfere with the functions of the nervous system. Most venoms contain neurotoxic substances. Myotoxins are included in this concept.
A species of anaerobic, gram-positive, rod-shaped bacteria in the family Clostridiaceae that produces proteins with characteristic neurotoxicity. It is the etiologic agent of BOTULISM in humans, wild fowl, HORSES; and CATTLE. Seven subtypes (sometimes called antigenic types, or strains) exist, each producing a different botulinum toxin (BOTULINUM TOXINS). The organism and its spores are widely distributed in nature.
A species of gram-positive bacteria which may be pathogenic for certain insects. It is used for the biological control of the Gypsy moth.
Venoms of arthropods of the order Araneida of the ARACHNIDA. The venoms usually contain several protein fractions, including ENZYMES, hemolytic, neurolytic, and other TOXINS, BIOLOGICAL.
Venoms from jellyfish; CORALS; SEA ANEMONES; etc. They contain hemo-, cardio-, dermo- , and neuro-toxic substances and probably ENZYMES. They include palytoxin, sarcophine, and anthopleurine.
One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.
Preparations of pathogenic organisms or their derivatives made nontoxic and intended for active immunologic prophylaxis. They include deactivated toxins. Anatoxin toxoids are distinct from anatoxins that are TROPANES found in CYANOBACTERIA.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)
The etiologic agent of CHOLERA.
The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.
Protein exotoxins from Staphylococcus aureus, phage type II, which cause epidermal necrolysis. They are proteins with a molecular weight of 26,000 to 32,000. They cause a condition variously called scaled skin, Lyell or Ritter syndrome, epidermal exfoliative disease, toxic epidermal necrolysis, etc.
Protein factors released from one species of YEAST that are selectively toxic to another species of yeast.
Toxins closely associated with the living cytoplasm or cell wall of certain microorganisms, which do not readily diffuse into the culture medium, but are released upon lysis of the cells.
A species of gram-negative, aerobic bacteria that is the causative agent of WHOOPING COUGH. Its cells are minute coccobacilli that are surrounded by a slime sheath.
The order Actiniaria, in the class ANTHOZOA, comprised of large, solitary polyps. All species are carnivorous.
An acute infection caused by the spore-forming bacteria BACILLUS ANTHRACIS. It commonly affects hoofed animals such as sheep and goats. Infection in humans often involves the skin (cutaneous anthrax), the lungs (inhalation anthrax), or the gastrointestinal tract. Anthrax is not contagious and can be treated with antibiotics.
Poisoning from toxins present in bivalve mollusks that have been ingested. Four distinct types of shellfish poisoning are recognized based on the toxin involved.
An acute inflammation of the INTESTINAL MUCOSA that is characterized by the presence of pseudomembranes or plaques in the SMALL INTESTINE (pseudomembranous enteritis) and the LARGE INTESTINE (pseudomembranous colitis). It is commonly associated with antibiotic therapy and CLOSTRIDIUM DIFFICILE colonization.
Infections with bacteria of the genus CLOSTRIDIUM.
The dose amount of poisonous or toxic substance or dose of ionizing radiation required to kill 50% of the tested population.
Glycosphingolipids which contain as their polar head group a trisaccharide (galactose-galactose-glucose) moiety bound in glycosidic linkage to the hydroxyl group of ceramide. Their accumulation in tissue, due to a defect in ceramide trihexosidase, is the cause of angiokeratoma corporis diffusum (FABRY DISEASE).
Use of naturally-occuring or genetically-engineered organisms to reduce or eliminate populations of pests.
A species of gram-positive, asporogenous bacteria in which three cultural types are recognized. These types (gravis, intermedius, and mitis) were originally given in accordance with the clinical severity of the cases from which the different strains were most frequently isolated. This species is the causative agent of DIPHTHERIA.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that is extremely pathogenic and causes severe dysentery. Infection with this organism often leads to ulceration of the intestinal epithelium.
A specific monosialoganglioside that accumulates abnormally within the nervous system due to a deficiency of GM1-b-galactosidase, resulting in GM1 gangliosidosis.
Usually 12,13-epoxytrichothecenes, produced by Fusaria, Stachybotrys, Trichoderma and other fungi, and some higher plants. They may contaminate food or feed grains, induce emesis and hemorrhage in lungs and brain, and damage bone marrow due to protein and DNA synthesis inhibition.
A genus of motile or nonmotile gram-positive bacteria of the family Clostridiaceae. Many species have been identified with some being pathogenic. They occur in water, soil, and in the intestinal tract of humans and lower animals.
Venoms from snakes of the family Elapidae, including cobras, kraits, mambas, coral, tiger, and Australian snakes. The venoms contain polypeptide toxins of various kinds, cytolytic, hemolytic, and neurotoxic factors, but fewer enzymes than viper or crotalid venoms. Many of the toxins have been characterized.
A family of extremely venomous snakes, comprising coral snakes, cobras, mambas, kraits, and sea snakes. They are widely distributed, being found in the southern United States, South America, Africa, southern Asia, Australia, and the Pacific Islands. The elapids include three subfamilies: Elapinae, Hydrophiinae, and Lauticaudinae. Like the viperids, they have venom fangs in the front part of the upper jaw. The mambas of Africa are the most dangerous of all snakes by virtue of their size, speed, and highly toxic venom. (Goin, Goin, and Zug, Introduction to Herpetology, 3d ed, p329-33)
A method of measuring the effects of a biologically active substance using an intermediate in vivo or in vitro tissue or cell model under controlled conditions. It includes virulence studies in animal fetuses in utero, mouse convulsion bioassay of insulin, quantitation of tumor-initiator systems in mouse skin, calculation of potentiating effects of a hormonal factor in an isolated strip of contracting stomach muscle, etc.
A compound that contains a reduced purine ring system but is not biosynthetically related to the purine alkaloids. It is a poison found in certain edible mollusks at certain times; elaborated by GONYAULAX and consumed by mollusks, fishes, etc. without ill effects. It is neurotoxic and causes RESPIRATORY PARALYSIS and other effects in MAMMALS, known as paralytic SHELLFISH poisoning.
Immunoglobulins produced in a response to BACTERIAL ANTIGENS.

The significance of cagA and vacA subtypes of Helicobacter pylori in the pathogenesis of inflammation and peptic ulceration. (1/8457)

AIMS: To assess the significance of cagA and vacA subtypes of Helicobacter pylori in relation to inflammation and density of bacterial colonisation in vivo within a dyspeptic UK population. METHODS: Dyspeptic patients who were Helicobacter pylori positive had antral samples taken for histology and culture. Gastroduodenal pathology was noted. The grade of bacterial density and inflammation was assessed using the Sydney system. Bacterial DNA was extracted and the vacA alleles and the cagA/gene typed using PCR. RESULTS: 120 patients were studied. There was high rate of cagA positive strains in this population. Bacterial density did not correlate with the presence of peptic ulceration. There was a significant association between cagA positive strains and increased inflammation and bacterial density. The vacA s1 type independently correlated with extensive chronic inflammation but there was no association with bacterial density. The vacA m type did not correlate with extent of inflammation or bacterial density. CONCLUSIONS: The results suggest that cagA is important in the pathogenesis of inflammation and peptic ulceration. These findings are in keeping with the hypothesis that cagA acts as a marker for a cag pathogenicity island which encodes several genes involved in inflammation. The vacA s1 allele correlates with inflammation independently of cagA, possibly through its enhanced ability to produce the vacuolating cytotoxin.  (+info)

Synergistic activation of JNK/SAPK by interleukin-1 and platelet-derived growth factor is independent of Rac and Cdc42. (2/8457)

The c-Jun N-terminal kinases (JNKs) are activated strongly by inflammatory cytokines and environmental stresses, but only weakly by growth factors. Here we show that platelet-derived growth factor (PDGF) strongly potentiates activation of JNK by interleukin 1 (IL-1) in human fibroblasts and a pig aortic endothelial (PAE) cell line. This synergistic activation of JNK by IL-1 and PDGF was unaffected by bacterial toxins that inactivate Rho proteins and Ras. Since Rho proteins have been implicated in JNK activation, their possible involvement was investigated further using stably expressed, inducible N17 or V12 mutants in PAE cell lines. N17 Rac non-selectively reduced JNK activity by 30% in resting or stimulated cells (IL-1 alone, or with PDGF). N17 Cdc42 had no effect. V12 Rac weakly activated JNK and synergized with IL-1, but not with PDGF. V12 Cdc42 weakly activated JNK, but synergized with PDGF and not IL-1. Our results imply that Rho GTPases are not directly involved in mediating IL-1-induced JNK activation, or in the potentiation of this activation by PDGF.  (+info)

Alpha-toxin and gamma-toxin jointly promote Staphylococcus aureus virulence in murine septic arthritis. (3/8457)

Septic arthritis is a common and feared complication of staphylococcal infections. Staphylococcus aureus produces a number of potential virulence factors including certain adhesins and enterotoxins. In this study we have assessed the roles of cytolytic toxins in the development of septic arthritis by inoculating mice with S. aureus wild-type strain 8325-4 or isogenic mutants differing in the expression of alpha-, beta-, and gamma-toxin production patterns. Mice inoculated with either an alpha- or beta-toxin mutant showed degrees of inflammation, joint damage, and weight decrease similar to wild-type-inoculated mice. In contrast, mice inoculated with either double (alpha- and gamma-toxin-deficient)- or triple (alpha-, beta-, and gamma-toxin-deficient)-mutant S. aureus strains showed lower frequency and severity of arthritis, measured both clinically and histologically, than mice inoculated with the wild-type strain. We conclude that simultaneous production of alpha- and gamma-toxin is a virulence factor in S. aureus arthritis.  (+info)

Role of Listeria monocytogenes exotoxins listeriolysin and phosphatidylinositol-specific phospholipase C in activation of human neutrophils. (4/8457)

Polymorphonuclear leukocytes (PMN) are essential for resolution of infections with Listeria monocytogenes. The present study investigated the role of the listerial exotoxins listeriolysin (LLO) and phosphatidylinositol-specific phospholipase C (PlcA) in human neutrophil activation. Different Listeria strains, mutated in individual virulence genes, as well as purified LLO were used. Coincubation of human neutrophils with wild-type L. monocytogenes provoked PMN activation, occurring independently of phagocytosis events, with concomitant elastase secretion, leukotriene generation, platelet-activating factor (PAF) synthesis, respiratory burst, and enhanced phosphoinositide hydrolysis. Degranulation and leukotriene formation were noted to be solely dependent on LLO expression, as these features were absent when the LLO-defective mutant EGD- and the avirulent strain L. innocua were used. These effects were fully reproduced by a recombinant L. innocua strain expressing LLO (INN+) and by the purified LLO molecule. LLO secretion was also required for PAF synthesis. However, wild-type L. monocytogenes was more potent in eliciting PAF formation than mutants expressing LLO, suggesting the involvement of additional virulence factors. This was even more obvious for phosphoinositide hydrolysis and respiratory burst: these events were provoked not only by INN+ but also by the LLO-defective mutant EGD- and by a recombinant L. innocua strain producing listerial PlcA. We conclude that human neutrophils react to extracellularly provided listerial exotoxins by rapid cell activation. Listeriolysin is centrally involved in triggering degranulation and lipid mediator generation, and further virulence factors such as PlcA apparently contribute to trigger neutrophil phosphoinositide hydrolysis and respiratory burst. In this way, listerial exotoxins may influence the host defense against infections with L. monocytogenes.  (+info)

Identification of a cytolethal distending toxin gene locus and features of a virulence-associated region in Actinobacillus actinomycetemcomitans. (5/8457)

A genetic locus for a cytolethal distending toxin (CDT) was identified in a polymorphic region of the chromosome of Actinobacillus actinomycetemcomitans, a predominant oral pathogen. The locus was comprised of three open reading frames (ORFs) that had significant amino acid sequence similarity and more than 90% sequence identity to the cdtABC genes of some pathogenic Escherichia coli strains and Haemophilus ducreyi, respectively. Sonic extracts from recombinant E. coli, containing the A. actinomycetemcomitans ORFs, caused the distension and killing of Chinese hamster ovary cells characteristic of a CDT. Monoclonal antibodies made reactive with the CdtA, CdtB, and CdtC proteins of H. ducreyi recognized the corresponding gene products from the recombinant strain. CDT-like activities were no longer expressed by the recombinant strain when an OmegaKan-2 interposon was inserted into the cdtA and cdtB genes. Expression of the CDT-like activities in A. actinomycetemcomitans was strain specific. Naturally occurring expression-negative strains had large deletions within the region of the cdt locus. The cdtABC genes were flanked by an ORF (virulence plasmid protein), a partial ORF (integrase), and DNA sequences (bacteriophage integration site) characteristic of virulence-associated regions. These results provide evidence for a functional CDT in a human oral pathogen.  (+info)

Zonula occludens toxin is a powerful mucosal adjuvant for intranasally delivered antigens. (6/8457)

Zonula occludens toxin (Zot) is produced by toxigenic strains of Vibrio cholerae and has the ability to reversibly alter intestinal epithelial tight junctions, allowing the passage of macromolecules through the mucosal barrier. In the present study, we investigated whether Zot could be exploited to deliver soluble antigens through the nasal mucosa for the induction of antigen-specific systemic and mucosal immune responses. Intranasal immunization of mice with ovalbumin (Ova) and recombinant Zot, either fused to the maltose-binding protein (MBP-Zot) or with a hexahistidine tag (His-Zot), induced anti-Ova serum immunoglobulin G (IgG) titers that were approximately 40-fold higher than those induced by immunization with antigen alone. Interestingly, Zot also stimulated high anti-Ova IgA titers in serum, as well as in vaginal and intestinal secretions. A comparison with Escherichia coli heat-labile enterotoxin (LT) revealed that the adjuvant activity of Zot was only sevenfold lower than that of LT. Moreover, Zot and LT induced similar patterns of Ova-specific IgG subclasses. The subtypes IgG1, IgG2a, and IgG2b were all stimulated, with a predominance of IgG1 and IgG2b. In conclusion, our results highlight Zot as a novel potent mucosal adjuvant of microbial origin.  (+info)

Hyperproduction of alpha-hemolysin in a sigB mutant is associated with elevated SarA expression in Staphylococcus aureus. (7/8457)

To evaluate the role of SigB in modulating the expression of virulence determinants in Staphylococcus aureus, we constructed a sigB mutant of RN6390, a prototypic S. aureus strain. The mutation in the sigB gene was confirmed by the absence of the SigB protein in the mutant on an immunoblot as well as the failure of the mutant to activate sigmaB-dependent promoters (e.g., the sarC promoter) of S. aureus. Phenotypic analysis indicated that both alpha-hemolysin level and fibrinogen-binding capacity were up-regulated in the mutant strain compared with the parental strain. The increase in fibrinogen-binding capacity correlated with enhanced expression of clumping factor and coagulase on immunoblots. The effect of the sigB mutation on the enhanced expression of the alpha-hemolysin gene (hla) was primarily transcriptional. Upon complementation with a plasmid containing the sigB gene, hla expression returned to near parental levels in the mutant. Detailed immunoblot analysis as well as a competitive enzyme-linked immunosorbent assay of the cell extract of the sigB mutant with anti-SarA monoclonal antibody 1D1 revealed that the expression of SarA was higher in the mutant than in the parental control. Despite an elevated SarA level, the transcription of RNAII and RNAIII of the agr locus remained unaltered in the sigB mutant. Because of a lack of perturbation in agr, we hypothesize that inactivation of sigB leads to increased expression of SarA which, in turn, modulates target genes via an agr-independent but SarA-dependent pathway.  (+info)

Responses of human intestinal microvascular endothelial cells to Shiga toxins 1 and 2 and pathogenesis of hemorrhagic colitis. (8/8457)

Endothelial damage is characteristic of infection with Shiga toxin (Stx)-producing Escherichia coli (STEC). Because Stx-mediated endothelial cell damage at the site of infection may lead to the characteristic hemorrhagic colitis of STEC infection, we compared the effects of Stx1 and Stx2 on primary and transformed human intestinal microvascular endothelial cells (HIMEC) to those on macrovascular endothelial cells from human saphenous vein (HSVEC). Adhesion molecule, interleukin-8 (IL-8), and Stx receptor expression, the effects of cytokine activation and Stx toxins on these responses, and Stx1 and Stx2 binding kinetics and bioactivity were measured. Adhesion molecule and IL-8 expression increased in activated HIMEC, but these responses were blunted in the presence of toxin, especially in the presence of Stx1. In contrast to HSVEC, unstimulated HIMEC constitutively expressed Stx receptor at high levels, bound large amounts of toxin, were highly sensitive to toxin, and were not further sensitized by cytokines. Although the binding capacities of HIMEC for Stx1 and Stx2 were comparable, the binding affinity of Stx1 to HIMEC was 50-fold greater than that of Stx2. Nonetheless, Stx2 was more toxic to HIMEC than an equivalent amount of Stx1. The decreased binding affinity and increased toxicity for HIMEC of Stx2 compared to those of Stx1 may be relevant to the preponderance of Stx2-producing STEC involved in the pathogenesis of hemorrhagic colitis and its systemic complications. The differences between primary and transformed HIMEC in these responses were negligible. We conclude that transformed HIMEC lines could represent a simple physiologically relevant model to study the role of Stx in the pathogenesis of hemorrhagic colitis.  (+info)

Glioblastomas are largely unresponsive to all available treatments and there is therefore an urgent need for novel therapeutics. Here we have probed the antineoplastic effects of a bacterial protein toxin, the cytotoxic necrotizing factor 1 (CNF1), in the syngenic GL261 glioma cell model. CNF1 produces a long-lasting activation of Rho GTPases, with consequent blockade of cytodieresis in proliferating cells and promotion of neuron health and plasticity. We have tested the antiproliferative effects of CNF1 on GL261 cells and human glioma cells obtained from surgical specimens. For the in vivo experiments, we injected GL261 cells into the adult mouse visual cortex, and five days later we administered either a single intracerebral dose of CNF1 or vehicle. To compare CNF1 with a canonical antitumoral drug, we infused temozolomide (TMZ) via minipumps for 1 week in an additional animal group. In culture, CNF1 was very effective in blocking proliferation of GL261 cells, leading them to multinucleation,
Bacterial Protein Toxins Hb ePUB Å Bacterial Protein PDF \ Designed for newcomers to the field of toxins this important volume is intended to show how these proteins work while providing an up to date review of the field Bacterial Protein Toxins describes all aspects of the biology of toxins including their synthesis and secretion from the bacterial cell their travels to and into the targ.
TY - JOUR. T1 - Mitochondrial proteins Bnip3 and Bnip3L are involved in anthrax lethal toxin-induced macrophage cell death. AU - Ha, Soon-Duck. AU - Ng, Dennis. AU - Lamothe, Julie. AU - Valvano, Miguel A. AU - Han, Jiahuai. AU - Kim, Sung Ouk. PY - 2007/9/7. Y1 - 2007/9/7. N2 - Anthrax lethal toxin (LeTx) induces rapid cell death of RAW246.7 macrophages. We recently found that a small population of these macrophages is spontaneously and temporally refractory to LeTx-induced cytotoxicity. Analysis of genome-wide transcripts of a resistant clone before and after regaining LeTx sensitivity revealed that a reduction of two closely related mitochondrial proteins, Bcl-2/adenovirus E1B 19-kDa interacting protein 3 (Bnip3) and Bnip3-like (Bnip3L), correlates with LeTx resistance. Down-regulation of Bnip3 and Bnip3L was also found in toxin-induced resistance whereby sublethal doses of LeTx induce resistance to subsequent exposure to cytolytic toxin doses. The role of Bnip3 and Bnip3L in LeTx-induced ...
[ Bacterial Protein Toxins ] - Home Etox18,4 Toxic Effects Of Fungi And Bacteria Damp Indoor Spaces And,Frontiers Bacterial Toxin Effector Membrane Targeting Outside
Get this from a library! Bacterial protein toxins. [J E Alouf; Centre national de la recherche scientifique (France); Federation of European Microbiological Societies.;]
In this paper, we observed the effects of mutating each of the six anionic residues lining the interior of the anthrax toxin channel to serines. Before discussing the effects of these mutations on cation selectivity, we must first address the possibility that streaming potentials and/or polarization effects (dilution potentials) may have skewed our results. By polarization effects, we mean that as a consequence of osmotic water flow across the membrane from the trans to the cis solution caused by the higher KCl concentration in the cis compartment, the KCl concentration at the cis membrane-solution interface is reduced, and at the trans membrane-solution interface it is elevated. Consequently, the actual acis/atrans across the membrane is less than the bulk acis/atrans, thereby artificially reducing the magnitude of Erev. To check for polarization effects, we performed cation selectivity experiments (not depicted) with valinomycin (which is ideally selective for potassium) at both [KCl]trans = ...
Mass spectrometry has recently become a powerful technique for bacterial identification. Mass spectrometry approaches generally rely upon introduction of the bacteria into a matrix-assisted laser-desorption time-of-flight (MALDI-TOF) mass spectrometer with mass spectrometric recognition of proteins specific to that organism that form a reliable fingerprint. With some bacteria, such as Bacillus anthracis and Clostridium botulinum, the health threat posed by these organisms is not the organism itself, but rather the protein toxins produced by the organisms. One such example is botulinum neurotoxin (BoNT), a potent neurotoxin produced by C. botulinum. There are seven known serotypes of BoNT, A-G, and many of the serotypes can be further differentiated into toxin variants, which are up to 99.9% identical in some cases. Mass spectrometric proteomic techniques have been established to differentiate the serotype or toxin variant of BoNT produced by varied strains of C. botulinum. Detection of potent ...
Lethal factor1,2-ETHANEDIOLGLYCEROLN~2~-[(4-fluoro-3-methylphenyl)sulfonyl]-N-hydroxy-N~2~-(pyridin-3-ylmethyl)-D-alaninamideZINC ION
ABSTRACTCytotoxic Necrotizing Factor 1 (CNF1) is a protein toxin from Escherichia coli that constitutively activates the Rho, Rac and Cdc42 GTPases. These regulatory proteins oscillate between a cytosolic GDP-bound inactive form and a membrane-linked GTP-bound active form, orchestrating the actin cy
TY - CHAP. T1 - Regulation systems of toxin expression. AU - Locht, Camille. AU - Lereclus, Didier. AU - Rood, Julian Ian. AU - Fournier, Benedicte. PY - 2006. Y1 - 2006. M3 - Chapter (Book). SN - 0120884453. SP - 64. EP - 82. BT - The Comprehensive Sourcebook of Bacterial Protein Toxins. A2 - Alouf, J. A2 - Popoff, M R. PB - Academic Press. CY - USA. ER - ...
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Proceedings of a workshop conference held under the auspices of the Federation of European Microbiological Societies and the Centre National de la Recherche Scientifique in Seillac, France from 26-30 June 1983 ...
Here we present the first global functional analysis of cellular responses to pore-forming toxins (PFTs). PFTs are uniquely important bacterial virulence factors, comprising the single largest class of bacterial protein toxins and being important for the pathogenesis in humans of many Gram positive …
Blood clots play an unexpected role in protecting the body from the deadly effects of bacteria by absorbing bacterial toxins, researchers at the University of California, Davis, have found. The research was published Dec. 2 in the journal PLoS ONE. Â Its a significant addition to the short list of defenses that animals use to protect themselves against toxin-induced sepsis, says Peter Armstrong, professor of molecular and cellular biology at UC Davis and senior author on the paper. Â Even with modern antibiotics, septic shock from bacterial infections afflicts about 300,000 people a year in the U.S., with a mortality rate of 30 to 50 percent. Septic shock is caused by Gram-negative bacteria, which release a toxin called lipopolysaccharide or endotoxin. In small amounts, lipopolysaccharide triggers inflammation. When infections with these bacteria get out of hand, lipopolysaccharide courses through the bloodstream, causing catastrophic damage to organs and tissues. Â These toxins cause disease
Bacterial protein toxins became valuable molecular tools for the targeted modulation of cell functions in experimental pharmacology and attractive therapeutics because of their potent and specific mode of action in human cells. C2IN-C3lim, a recombinant fusion toxin (~50 kDa) of the Rho-inhibiting C …
A bacterial toxin promoting tissue healing has been discovered. The compound, found in Staphylococcus aureus, does not just damage cells, but also stimulates tissue regeneration ...
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n: anatoxin, toxoid} a bacterial toxin that has been weakened until it is no longer toxic but is strong enough to induce the formation of antibodies and immunity to the specific disease caused by the toxin ...
You get an infection, you are given penicillin -- and then you could get hemorrhagic diarrhea. This rare but extremely unpleasant side reaction can be
Scientists shed light on the neurological consequences of exposure to low-levels of nerve agents and suggest a drug that could treat some of the toxins effects.
In chapter 3, The Sense of Sensibility, author Wendy Jones uses scenes from one of Jane Austens most celebrated novels to illustrate the functioning of the bodys stress response system.. 0 Comments. ...
Newborns deprived of oxygen have their temperatures lowered to protect against brain damage, but its hard to decipher the babies immediate response to the intervention.. 0 Comments. ...
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It has been well established that allergies foods and toxins cause muscle weekness The basic principle of muscle testing is muscle weak or muscle strong now you can test the foods you use and the toxins in your enviroment by using this muscle strength weakness principle .,
Septicemia is a term formerly accepted by the medical profession to mean the rapid multiplication of bacteria and the presence of bacterial toxins in the blood.
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Clostridium perfringens epsilon toxin (ETX) rapidly kills MDCK II cells at 37°C, but not 4°C. The current study shows that, in MDCK II cells, ETX binds and forms an oligomeric complex equally well at 37°C and 4°C but only forms a pore at 37°C. However, the complex formed in MDCK cells treated with ETX at 4°C has the potential to form an active pore, since shifting those cells to 37°C results in rapid cytotoxicity. Those results suggested that the block in pore formation at 4°C involves temperature-related trapping of ETX in a prepore intermediate on the MDCK II cell plasma membrane surface. Evidence supporting this hypothesis was obtained when the ETX complex in MDCK II cells was shown to be more susceptible to pronase degradation when formed at 4°C vs. 37°C; this result is consistent with ETX complex formed at 4°C remaining present in an exposed prepore on the membrane surface, while the ETX prepore complex formed at 37°C is unaccessible to pronase because it has inserted into the ...
TY - JOUR. T1 - Production of a fusion protein consisting of the enterotoxigenic Escherichia coli heat-labile toxin B subunit and a tuberculosis antigen in Arabidopsis thaliana. AU - Rigano, M. M.. AU - Alvarez, M. L.. AU - Pinkhasov, J.. AU - Jin, Y.. AU - Sala, F.. AU - Arntzen, C. J.. AU - Walmsley, A. M.. PY - 2004/2. Y1 - 2004/2. N2 - Transgenic plants are potentially safe and inexpensive vehicles to produce and mucosally deliver protective antigens. However, the application of this technology is limited by the poor response of the immune system to non-particulate, subunit vaccines. Co-delivery of therapeutic proteins with carrier proteins could increase the effectiveness of the antigen. This paper reports the ability of transgenic Arabidopsis thaliana plants to produce a fusion protein consisting of the B subunit of the Escherichia coli heat-labile enterotoxin and a 6 kDa tuberculosis antigen, the early secretory antigenic target ESAT-6. Both components of the fusion protein were detected ...
Pulpy kidney disease is an important fatal enterotoxaemia of sheep and occasionally other ruminants. Although history, clinical signs, post mortem picture, histopathological findings and demonstration of glucosuria are helpful in diagnosing the disease, the demonstration of Clostridium perfringens epsilon toxin in the small intestine is a useful additional aid to diagnosis. Methods used to assay the toxin in the gut must be specific and sensitive, as the toxin is highly potent and small amounts can be significant in nonimmune animals, as little as 0.3 ng of activated toxin being sufficient to kill a mouse. The biological test is therefore a sensitive method for measuring toxin. However, unless small intestine contents are titrated in a number of mice it is not a quantitative method and is currently viewed with disfavour on humanitarian grounds. Although other tests have been used, for example the reversed phase passive haemagglutination, radial immunodiffusion and counter immunoelectrophoresis ...
Cytotoxic necrotizing factor type 2 (CNF2) produced by Escherichia coli strains isolated from intestinal and extraintestinal infections is a dermonecrotic toxin of 110 kDa. We cloned the CNF2 gene from a large plasmid carried by an Escherichia coli strain isolated from a lamb with septicemia. Hydropathy analysis of the deduced amino acid sequence revealed a largely hydrophilic protein with two potential hydrophobic transmembrane domains. The N-terminal half of CNF2 showed striking homology (27% identity and 80% conserved residues) to the N-terminal portion of Pasteurella multocida toxin. Methylamine protection experiments and immunofluorescence studies suggested that CNF2 enters the cytosol of the target cell through an acidic compartment and induces the reorganization of actin into stress fibers. Since the formation of stress fibers in eukaryotic cells involves Rho proteins, we radiolabeled these small GTP-binding proteins from CNF2-treated and control cells with a Rho-specific ...
Escherichia coli heat-labile enterotoxin, molecular model. This is one of several proteins produced by pathogenic E. coli bacteria in the intestines. Unlike the heat-stable enterotoxin, this one is inactivated at high temperatures. The toxin causes diarrhoea and can be fatal in severe cases. This protein consists of three subunits with a total of seven chains and a total of 329 amino acids. - Stock Image C025/1673
Clostridium difficile toxin B is a toxin produced by the bacteria Clostridium difficile. C. difficile produces two major kinds of toxins that are very potent and lethal; an enterotoxin (Toxin A) and a cytotoxin (Toxin B, this protein). Toxin B (TcdB) is a cytotoxin that has a molecular weight of 270 kDa and an isoelectric point, pl, of 4.1. Toxin B has four different structural domains: catalytic, cysteine protease, translocation, and receptor binding. The N-terminal glucosyltransferase catalytic domain includes amino acid residues 1-544 while the cysteine protease domain includes residues 545-801. Additionally, the translocation region incorporates amino acid residues from 802 to 1664 while the receptor binding region is part of the C-terminal region and includes amino acid residues from 1665 to 2366. The glycosylation activity of toxin B occurs in the N-terminal catalytic region (residues 1-544). This region glycosylates substrates independent of any cytotoxic activity. However, a small ...
OBJECTIVE: Neurotrophins and extracellular matrix (ECM) molecules are involved in neurite guidance during the development of spiral ganglion (SG) neurons. Several intracellular signaling molecules can be activated by ECMs and neurotrophins via their cognate receptors. In other systems these include the Rho small GTPases, which influence reorganization of the actin cytoskeleton that is required for axon growth. The aim of this study was to determine whether neurotrophin-3 (NT-3)-mediated SG neurite outgrowth on laminin-1 (LN) is dependent on the activation of the small GTPases Rho/Rac/Cdc42. MATERIAL AND METHODS: SG explants from postnatal day 4 rats were cultured on LN with and without NT-3 and increasing concentrations of Clostridium difficile Toxin B, an inhibitor of Rho GTPases. After fixation and immunocytochemical labeling, neurite growth was evaluated. RESULTS: Treatment with C. difficile Toxin B without NT-3 led to a dose-dependent decrease in the length and number of processes on LN. In ...
DESCRIPTION (provided by applicant): C. perfringens epsilon-toxin (ETX) is a potential biological weapon included in the list of category B priority agents. The overall goal of this proposal is to identify and perform in vivo testing of new inhibitors of E TX using a novel approach for the inactivation of pore-forming toxins developed at Innovative Biologics, Inc. It is based on the blocking of the target pore with molecules having the same symmetry as the pore itself. Results from our SBIR Phase I project d emonstrated that beta-cyclodextrin derivatives designed to block the transmembrane channel formed by epsilon-toxin can inhibit its cytotoxicity at low micromolar concentrations. Based on the successful completion of this feasibility study, we propose to de sign, synthesize and screen a library of beta-cyclodextrin derivatives for inhibitors of epsilon-toxins activity and test selected lead compounds in mice. The specific aims of this Phase II study are: (1) Optimize the assay for testing ...
A toxin-antitoxin system is a set of two or more closely linked genes that together encode both a protein poison and a corresponding antidote. When these systems are contained on plasmids - transferable genetic elements - they ensure that only the daughter cells that inherit the plasmid survive after cell division. If the plasmid is absent in a daughter cell, the unstable antitoxin is degraded and the stable toxic protein kills the new cell; this is known as post-segregational killing (PSK). Toxin-antitoxin systems are widely distributed in prokaryotes, and organisms often have them in multiple copies. Toxin-antitoxin systems are typically classified according to how the antitoxin neutralises the toxin. In a Type I toxin-antitoxin system, the translation of messenger RNA (mRNA) that encodes the toxin is inhibited by the binding of a small non-coding RNA antitoxin to the mRNA. The protein toxin in a type II system is inhibited post-translationally by the binding of another protein ...
Binary toxins are among the most potent bacterial protein toxins performing a cooperative mode of translocation and exhibit fatal enzymatic activities in eukaryotic cells. Anthrax and C2 toxin are the most prominent examples for the AB(7/8) type of toxins. The B subunits bind both host cell receptors and the enzymatic A polypeptides to trigger their internalization and translocation into the host cell cytosol. C2 toxin is composed of an actin ADP-ribosyltransferase (C2I) and C2II binding subunits. Anthrax toxin is composed of adenylate cyclase (EF) and MAPKK protease (LF) enzymatic components associated to protective antigen (PA) binding subunit. The binding and translocation components anthrax protective antigen (PA(63)) and C2II of C2 toxin share a sequence homology of about 35%, suggesting that they might substitute for each other. Here we show by conducting in vitro measurements that PA(63) binds C2I and that C2II can bind both EF and LF. Anthrax edema factor (EF) and lethal factor (LF) have ...
Clostridium difficile Toxin B antibody [5156] for ELISA. Anti-Clostridium difficile Toxin B mAb (GTX41669) is tested in Clostridium difficile samples. 100% Ab-Assurance.
Cellular adaptation to microbial stresses has been demonstrated in several cell types. Macrophages (MФ) are sentinel immune cells fending off invading microbes. Anthrax lethal toxin (LeTx) is a key virulence factor released by Bacillus anthracis that causes rapid cell death, pyroptosis. A small number of RAW246.7 macrophages (~4%) exposed to a non-lethal dose of LeTx become resistant to LeTx-induced pyroptosis for ~ 4 weeks, termed
Invitrogen Anti-Clostridium difficile Toxin B Monoclonal (E74F), Catalog # MA1-7417. Tested in ELISA (ELISA) applications. This antibody reacts with Bacteria samples. Supplied as 100 µg purified antibody (0.1 mg/mL).
The Bacillus anthracis lethal factor (LF) is one component of a tripartite exotoxin partly responsible for persistent anthrax cytotoxicity after initial bacterial infection. Inhibitors of the zinc metalloproteinase have been investigated as potential therapeutic agents, but LF is a challenging target because inhibitors lack sufficient selectivity or possess poor pharmaceutical properties. These structural studies reveal an alternate conformation of the enzyme, induced upon binding of specific inhibitors, that opens a previously unobserved deep pocket termed S1* which might afford new opportunities to design selective inhibitors that target this subsite. ...
Bacillus anthracis secretes the edema toxin (ET) that disrupts the cellular physiology of endothelial and immune cells, ultimately affecting the adherens
Cytolytic pore-forming toxins are important for the virulence of many disease-causing bacteria. How target cells molecularly respond to these toxins and whether or not they can mount a defense are poorly understood. By using microarrays, we demonstrate that the nematode Caenorhabditis elegans responds robustly to Cry5B, a member of the pore-forming Crystal toxin family made by Bacillus thuringiensis. This genomic response is distinct from that seen with a different stressor, the heavy metal cadmium. A p38 mitogen-activated protein kinase (MAPK) kinase and a c-Jun N-terminal-like MAPK are both transcriptionally up-regulated by Cry5B. Moreover, both MAPK pathways are functionally important because elimination of either leads to animals that are (i) hypersensitive to a low, chronic dose of toxin and (ii) hypersensitive to a high, brief dose of toxin such that the animal might naturally encounter in the wild. These results extend to mammalian cells because inhibition of p38 results in the hypersensitivity
Interaction between bacterial toxins and cellular surface receptors is an important component of host-pathogen interaction. Anthrax toxin protective antigen (PA...
Phenol-soluble modulins are secreted peptides with multiple functions in Staphylococcus aureus pathogenesis and spreading. Recent studies by Otto and coworkers show that these hellhounds of the staphylococcal virulence-factor pandemonium are unleashed through an essential ABC transporter, which represents an exciting new target for stopping the spread of this important pathogen.. ...
Read Influence of Cys-130 S. aureus Alpha-toxin on Planar Lipid Bilayer and Erythrocyte Membranes, The Journal of Membrane Biology on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
Identification of Clostridium Perfringens Epsilon Toxin as a Candidate Environmental Trigger for Nascent Lesion Formation in MS (Timothy Vartanian, MD, PhD ...
TY - JOUR. T1 - Enteric bacterial toxins. T2 - Mechanisms of action and linkage to intestinal secretion. AU - Sears, Cynthia L.. AU - Kaper, James B.. PY - 1996/3/1. Y1 - 1996/3/1. N2 - A wide range of bacteria have been implicated as potential etiologies of diarrheal disease. Many of these organisms have been reported to produce one or more toxins postulated as important in the pathogenesis of the diarrhea resulting from infection with the organism. The primary goal of this review is to critically assess the linkage between the mechanism of action of toxins produced by human enteric pathogens and the stimulation of intestinal secretion. To accomplish this goal, the range of criteria used to demonstrate pathogenicity of an enteric bacterial toxin and potential mechanisms stimulating net intestinal secretion are reviewed. A detailed description of each enteric toxin is presented, and revised criteria are proposed for classification of enteric bacterial toxins. Throughout this review, emphasis has ...
From a structural perspective, the most compelling conclusion emerging from our findings is that the channels entire β-barrel stem region participates in the gating process. Absent a high resolution structure of the pore form of the anthrax channel in both the closed and open states, we cannot draw a detailed picture of the gating motions from our data. Nevertheless, we can gain some insight into the magnitude of the conformational changes that might occur during gating by considering the x-ray crystal structure of α-hemolysin, which likely shares structural features with the stem domain of the anthrax channel (Song et al., 1996; Benson et al., 1998; Nassi et al., 2002; Krantz et al., 2004; Nguyen, 2004).. The luminal diameter (Cα-Cα) of α-hemolysins β-barrel is ∼26 Å (accounting for sidechain volume, which is relevant to LF or EF translocation, yields a diameter of ∼19 Å [Krantz et al., 2004]), with residues of adjacent subunits being an average distance (Cβ-Cβ) of ∼11 Å from ...
Some pathogenic species of Clostridium employ the classic enzymatic AB binary protein toxins for poisoning cells. Clostridium perfringens, C. difficile, C. spiroforme, and C. botulinum all use similar binary toxins (iota toxin (Ia and Ib), CDT (CDTa and CDTb), CST (CSTa and CSTb), and C2 toxin (C2I and C2II), respectively). They consist of the enzymatic A component, an actin-specific ADP-ribosyltransferase and the B component that binds to the host cell and forms a membrane-spanning pore that functions as the translocation channel for each enzymatic component. The B component translocates the A component into the host cell via the membrane in the acidic endosome. In contrast, the Bacillus anthracis species uses a different binary toxin, which consists of two enzymatic proteins: the lethal (LF) and edema (EF) factors, and a protein translocation channel, PA. The PA heptameric pore structure was revealed to have extremely narrow φ-clamp passageway and a long membrane-spanning channel. ...
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Webb, Helen M. and Sixma, T.K. and Hol, W.G.J. and Hirst, Timothy R. (1994) Analysis by Site-Directed Mutagenesis of Important Residues Invoved in the Assembly of Escherichia-Coli Heart-Labile NALYSIS BY SITE-DIRECTED MUTAGENESIS OF IMPORTANT RESIDUES Enterotoxin. In: 6th European Workshop on Bacterial Protein Toxins, Stirling, Scotland. (The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided) ...
Principal Investigator:TOMITA Toshio, Project Period (FY):1993 - 1994, Research Category:Grant-in-Aid for General Scientific Research (C), Research Field:Bacteriology (including Mycology)
A BLAST search with the HI0659 protein sequence turns up homologs in only the same species. Some of these are annotated as members of an Xre-family toxin-antitoxin system (I think HI0660 is homologous to the toxin component, and HI0659 to the antitoxin component). HI0660 is also tagged as a member of the Gp49 superfamily (also phage proteins I think). Xre family repressors are known to perform a variety of regulatory functions unrelated to toxin-antitoxin systems (ref). The same paper suggests that the Tad toxin components might be mRNA-cleaving ribonucleases. Maybe thats what HI0660 does, and HI0659 is a repressor that prevents it from acting. If so, and if sxy mRNA was HI0660s target, then the mutant phenotypes would make sense. ...
Study Flashcards On USMLE 2011 Bacterial Toxins/Virulence Factors at Quickly memorize the terms, phrases and much more. makes it easy to get the grade you want!
View List Labs product catalog containing bacterial toxins, GMP, antibodies, FRET peptides, toxoids, vaccine carrier proteins & adjuvants and more.
Researchers from the University of Maryland School of Medicine and their colleagues have identified the structure of the most lethal toxin produced by certain strains of Clostridium difficile bacteria, a potentially deadly infection associated with the use of antibiotics. The
DI-fusion, le Dépôt institutionnel numérique de lULB, est loutil de référencementde la production scientifique de lULB.Linterface de recherche DI-fusion permet de consulter les publications des chercheurs de lULB et les thèses qui y ont été défendues.
It is difficult to correlate in vitro toxin concentration with in vivo exposure, however, the concentration of toxin used in both models are similar as 2.3 mg DON/kg of feed corresponds to 7.7 μM ( Sergent et al., 2006; Pinton et al., 2009). It is interesting to observe that in both models, there is a good correlation in the increase of expression of phosphorylated MAPK. The extent of MAPK activation, lower in samples obtained from the in vivo experiment than in explants, could be explained by the mode of exposure to the toxin, in the culture medium. or in ingested feed. A significant increase was observed only for ERK and p38. Following the same signaling arrangement, each individual MAPK pathway responds PF-02341066 in vivo to specific stimuli and then regulates their specific substrates ( Cui et al., 2007), which can explain the selective activation of MAPK. JNK and ERK are involved in regulation of both cell survival and death depending on cell types and stimulus, whereas p38 can promote ...
Fluid therapy concerns the administration of fluids to bring down (and keep down) the toxin levels of kidney failure. There are many ways to deliver fluids.
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1DJR: Structure of m-carboxyphenyl-alpha-D-galactopyranoside complexed to heat-labile enterotoxin at 1.3 A resolution: surprising variations in ligand-binding modes.
HLT 314V Week 2 Discussion 1 & Discussion 2HLT 314V Week 2 Discussion 1Select one area of health policy and describe the impact that policy formation places
Affiliation:兵庫県立大学,環境人間学部,教授, Research Field:食生活,食の安全, Keywords:プルプリン,ノロウイルス,緑茶,サルモネラ,マウス,Verotoxin,イムノクロマト法,Heat-labile toxin,ハムスター,クロロゲン酸, # of Research Projects:2, # of Research Products:9
Bacterial. toxins. Exotoxin. Gram. positive. Bacilli. .mw-parser-output .nobold{font-weight:normal}. Clostridium:. *tetani * ... "toxin" at Dorland's Medical Dictionary *^ "toxin - Definition from the Merriam-Webster Online Dictionary". Retrieved 13 ... For other uses, see Toxin (disambiguation).. A toxin (from Ancient Greek: τοξικόν, translit. toxikon) is a poisonous substance ... 3 Environmental toxins *3.1 Finding information about toxins. *3.2 Computational resources for prediction of toxic peptides and ...
Bacterial. toxins. Exotoxin. Gram. positive. Bacilli. .mw-parser-output .nobold{font-weight:normal}. Clostridium:. *tetani * ... note: some toxins are produced by lower species and pass through intermediate species ... Cardiotoxin III (CTX III, also known as cytotoxin 3) is a sixty amino-acid polypeptide toxin from the Taiwan Cobra Naja atra. ... Snake toxin-like (2 families) - Orientations of Proteins in Membranes (OPM) database". Retrieved 2008-12-13.. .mw-parser-output ...
note: some toxins are produced by lower species and pass through intermediate species ... Histrionicotoxins are a group of related toxins found in the skin of poison frogs from the family Dendrobatidae, notably ...
Bacterial. toxins. Exotoxin. Gram. positive. Bacilli. .mw-parser-output .nobold{font-weight:normal}. Clostridium:. *tetani * ... note: some toxins are produced by lower species and pass through intermediate species ... Nevertheless, they appear much less capable of causing mutagenesis than the unmetabolized toxin.[19] ... and the possibility of concurrent exposure to other toxins. The main target organ in mammals is the liver, so aflatoxicosis ...
Its adult length can range from 5 to 8 in (13 to 20 cm).[1] Its skin produces a potent toxin[citation needed]. ... note: some toxins are produced by lower species and pass through intermediate species ... This evolutionary arms race has resulted in the newts producing levels of toxin far in excess of what is needed to kill any ... The mutations in the snake's genes that conferred resistance to the toxin have resulted in a selective pressure that favors ...
... is a type of labile toxin found in Escherichia coli and Bacillus cereus. ... note: some toxins are produced by lower species and pass through intermediate species ... It acts similarly to the cholera toxin by raising cAMP levels through ADP-ribosylation of the alpha-subunit of a Gs protein ... In addition to its effects on chloride secretion, which involve the same steps as the effects of cholera toxin, heat-labile ...
note: some toxins are produced by lower species and pass through intermediate species ... Possani, L.D.; Becerrill, B.; Delepierre, M.; Tytgat Hammock, J. (1999). "Scorpion toxins specific for Na+-channels". European ... Gordon, D.; Savarin, P.; Gurevitz, M.; Zinn-Justin, S. (1998). "Functional anatomy of scorpion toxins affecting sodium channels ... Other peptide toxins found in the venom include: dortoxin, a lethal peptide; bestoxin, which causes writhing in mice; and ...
... can be activated by components of the immune system, such as the complement system; bacterial toxins; activated ... Toxins and pathogens may cause necrosis; toxins such as snake venoms may inhibit enzymes and cause cell death.[11] Necrotic ... Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma which result in the ... the use of anti-venom halts the spread of toxins whilst receiving antibiotics to impede infection.[19] ...
Bacterial. toxins. Exotoxin. Gram. positive. Bacilli. .mw-parser-output .nobold{font-weight:normal}. Clostridium:. *tetani * ... note: some toxins are produced by lower species and pass through intermediate species ... Scorpions such as the deathstalker paralyze their prey by injecting a potent mix of peptide toxins.[4] Charybdotoxin, a 37 ... The Charybdotoxin family of scorpion toxins is a group of small peptides that has many family members, such as the pandinotoxin ...
... which he considered to be a toxin kept "within" the bacterial cell and released only after destruction of the bacterial cell ... "Toxins. 10 (8): 326. doi:10.3390/toxins10080326. PMC 6115757. PMID 30103489.. *^ Meseguer, Victor; Alpizar, Yeranddy A.; Luis, ... oryzae, the bacterial leaf blight pathogen of rice". BMC Microbiol. 4: 40. doi:10.1186/1471-2180-4-40. PMC 524487. PMID ... note: some toxins are produced by lower species and pass through intermediate species ...
For bacterial transformation to take place, the recipient bacteria must be in a state of competence, which may occur in nature ... Cyanobacteria produce a range of toxins known as cyanotoxins that can pose a danger to humans and animals. The cyanobacteria ... Archean Eon Bacterial phyla, other major lineages of Bacteria Biodiesel Cyanobiont Endosymbiotic theory Geological history of ... Blue-Green Algae (Cyanobacteria) and their Toxins. (2013-01-30). Retrieved on 2014-04-19. Harmful Bloom in Lake ...
Bacterial myocarditis is rare in patients without immunodeficiency. Toxins[edit]. *Drugs, including alcohol, anthracyclines and ... Myocarditis is most often due to a viral infection.[1] Other causes include bacterial infections, certain medications, toxins, ... Usually viral infection, also bacterial infections, certain medications, toxins, autoimmune disorders[1][2]. ... Bacterial (Brucella, Corynebacterium diphtheriae, gonococcus, Haemophilus influenzae, Actinomyces, Tropheryma whipplei, Vibrio ...
Proft, Thomas (2013). Bacterial Toxins: Genetics, Cellular Biology and Practical Applications. Horizon Scientific Press. ISBN ... These bacterial strains present a thickening of the cell wall, which is believed to reduce the ability of vancomycin to diffuse ...
... s may also mediate bacterial escape from host cells. Regulation of gene expression[edit]. The regulation of gene ... Gouaux E (1998). "α-Hemolysin from Staphylococcus aureus: an archetype of β-barrel, channel-forming toxins". J. Struct. Biol. ... They are unique in that they come in two components, and hence are referred to as bi-component toxins (InterPro: IPR003963). ... β-hemolysin (hlb; Q2FWP1) is a Phospholipase C toxin secreted by S. aureus. Upon investigating sheep erythrocytes, its toxic ...
European mistletoe Ricin Gill DM (1982). "Bacterial toxins: a table of lethal amounts" (pdf). Microbiological Reviews. 46 (1): ... Abrin is a ribosome inhibiting protein like ricin, a toxin which can be found in the seeds of the castor oil plant. It is ... March 2009). "Quantification of L-Abrine in Human and Rat Urine: A Biomarker for the Toxin Abrin" (PDF). Journal of Analytical ...
Pitcher, M C; Cummings, J H (1996-07-01). "Hydrogen sulphide: a bacterial toxin in ulcerative colitis?". Gut. 39 (1): 1-4. doi: ...
Millar, Ian; Gray, David; Kay, Helen (1998). "Bacterial toxins found in foods". In Watson, David H. (ed.). Natural Toxicants in ... The Hbl and Nhe toxins are pore-forming toxins closely related to ClyA of E. coli. The proteins exhibit a conformation known as ... Bacterial growth results in production of enterotoxins, one of which is highly resistant to heat and acids (pH levels between 2 ... Emetic toxin can withstand 121 °C (250 °F) for 90 minutes. The diarrhetic syndromes observed in patients are thought to stem ...
Pizza, Mariagrazia; Fontana, Maria Rita; Scarlato, Vincenzo; Rappuoli, Rino (1996). "Genetic Detoxification of Bacterial Toxins ... a non-toxic mutant of diphtheria toxin: Use as a conjugation protein in vaccines and other potential clinical applications". ... conjugate vaccine against meningococcal-C disease and the first recombinant bacterial vaccine against pertussis. Currently,[ ... an acellular pertussis vaccine containing a genetically detoxified pertussis toxin; the first conjugate vaccines against ...
Bacterial agglutinins and precipitins. Serum substances that agglutinate bacteria. and precipitate bacterial toxins. von Gruber ... the activity of toxins, enabling passive immunization. von Behring and Kitasato (1890)[4] ... It also refers to the effector functions of antibodies, which include pathogen and toxin neutralization, classical complement ... In 1890, filtrates of diphtheria, later named diphtheria toxins, were used to vaccinate animals in an attempt to demonstrate ...
158-. ISBN 978-0-306-44077-9. Hardegree, M. Carolyn; Tu, Anthony T. (5 August 1988). Handbook of Natural Toxins: Bacterial ... "Cholera Toxins: Immunogenicity of the Rabbit Ileal Loop Toxin and Related Antigens" (PDF). American Society for Microbiology. ... Dutta N. K., Panse N. V., Kulkarni D. R. (1959). "Role of cholera a toxin in experimental cholera". J. Bacteriol. 78 (4): 594-5 ... Dutta was associated with the World Health Organization, serving as a member of their Experts' Panel in Bacterial Diseases and ...
Lax, Alistair J. (2005). Toxin: the cunning of bacterial poisons. Oxford University Press. p. 130. ISBN 0-19-860558-7. Ma Anand ...
ISBN 978-1-4381-0990-9. Lax A (27 October 2005). Toxin: The cunning of bacterial poisons. Oxford University Press. ISBN 978-0- ... When compared with chlorhexidine in one small study, it was found to be less effective at reducing oral bacterial load, ... Xylitol rinses double as a bacterial inhibitor and have been used as substitute for Alcohol to avoid dryness of mouth ... When used in mouthwash (e.g. 0.03%), there is moderate substantivity, broad spectrum anti-bacterial action, some anti-fungal ...
ISBN 0-520-24018-9. Lax, Alistair J. (2005). Toxin: The Cunning of Bacterial Poisons. Oxford University Press, USA. ISBN 0-19- ...
The Comprehensive Sourcebook of Bacterial Protein Toxins. Academic Press. pp. 862-871. ISBN 978-0-08-045698-0. Robins-Browne, R ... Superantigens, bacterial adhesions, and the actions of Yops (which are bacterial proteins once thought to be "Yersinia outer ... Numerous bacterial small non-coding RNAs have been identified to play regulatory functions. Some can regulate the virulence ... Lee VT, Tam C, Schneewind O (2000). "LcrV, a substrate for Yersinia enterocolitica type III secretion, is required for toxin ...
Gonzalez MR, Bischofberger M, Pernot L, van der Goot FG, Frêche B (February 2008). "Bacterial pore-forming toxins: the (w)hole ... Tilley SJ, Orlova EV, Gilbert RJ, Andrew PW, Saibil HR (April 2005). "Structural basis of pore formation by the bacterial toxin ... In Alouf, J. E. & Popoff, M. R. (Eds.) The Comprehensive Sourcebook of Bacterial Protein Toxins. 3rd ed., pp. 643-658, Oxford, ... Heuck AP, Moe PC, Johnson BB (2010). "The cholesterol-dependent cytolysin family of gram-positive bacterial toxins". ...
Woerner, Amanda (29 January 2014). "Bacterial toxin may trigger multiple sclerosis, research finds". Jawetz Melnick & Adelbergs ... The toxin involved in gas gangrene is α-toxin, which inserts into the plasma membrane of cells, producing gaps in the membrane ... Tests in mice found that a toxin made by a rare strain of C. perfringens caused MS-like damage in the brain, and earlier work ... One side of the plate contains anti-alpha-toxin, while the other side does not. A streak of suspect organism is placed through ...
The mechanism of pore formation by bacterial toxins. Curr Opin Struct Bio 16:230-236. Then, C. 2010. Risk assessment of toxins ... The gene then codes for delta endotoxins (Cry proteins) which are toxins that are very potent and provoke lesions in the cell ... Proteins need specific receptors on cells in order to form the Cry proteins and become toxic, which is why the toxins are ... paper: i) important claims about the Daphnia magna study are incorrect (that the amount of toxin in the experiment was not ...
"J Venom Anim Toxins Incl Trop Dis. 20 (1): 44. doi:10.1186/1678-9199-20-44. PMC 4197285. PMID 25320574.. ... balance as well as treating any bacterial infections that may develop.[33] Dialysis may be needed for kidney failure, and ...
Lizak C, Gerber S, Numao S, Aebi M, Locher KP (June 2011). "X-ray structure of a bacterial oligosaccharyltransferase". Nature. ... Diphtheria toxin. *NAD(P)+:arginine ADP-ribosyltransferase *Pertussis toxin. *Cholera toxin. *Poly ADP ribose polymerase ...
The government started hailing the use of enamel tanks as easy to clean, lasting forever, and being devoid of bacterial ... oryzae lacks the ability to produce toxins, unlike the closely related Aspergillus flavus.[15] To date, there have been only ...
... has been introduced into tomato plants and in vivo studies show significant resistance to bacterial wilt and bacterial spot.[27 ... The insecticidal toxin from the bacterium Bacillus thuringiensis has been inserted into a tomato plant.[22] When field tested ... In 2000, the concentration of pro-vitamin A was increased by adding a bacterial gene encoding phytoene desaturase, although the ... "Control of Ethylene Synthesis by Expression of a Bacterial Enzyme in Transgenic Tomato Plants". The Plant Cell. 3 (11): 1187- ...
Abel-Santos, E (editor) (2012). Bacterial Spores: Current Research and Applications. Caister Academic Press. ISBN 978-1-908230- ... Further information: Bacterial morphological plasticity. Under conditions of starvation, especially the lack of carbon and ... While the rest of a bacterial cell may stain, the endospore is left colourless. To combat this, a special stain technique ... Bacterial endospores are resistant to antibiotics, most disinfectants, and physical agents such as radiation, boiling, and ...
Therefore, macrophage membranes become susceptibile to bacterial infections.[11] Reproductive system[edit]. In experiments with ... such as cytochromes P450 have increased activities in the gut for protection from food-borne toxins. Thus, in most cases, small ... pyrene confers enhanced susceptibility to bacterial infection". Environ Research. 146: 173-84. doi:10.1016/j.envres.2015.12.027 ... which is a eucaryotic receptor for bacterial surface structures such as lipoteichoic acid. ...
As an example of the relationship between the IMP (in this case the bacterial phototrapping pigment, bacteriorhodopsin) and the ... MT7 snake toxin bound to dimeric hM1 muscarinic receptor". J Biol Chem. 286 (36): 31661-75. doi:10.1074/jbc.M111.261404. PMC ...
Some diseases, such as tetanus, cause disease not by bacterial growth but by bacterial production of a toxin. Tetanus toxin is ... amount of toxin and time required to kill a person is much less than is required by the immune system to recognize the toxin ... and produce antibodies against it.[17] However the tetanus toxin is easily denatured losing its ability to produce disease, but ...
Epidermolytic toxin-producing staphylococci as the etiologic agent of the fourth childhood exanthem". American Journal of ... One of the exotoxins is encoded on the bacterial chromosome, while the other is encoded on a plasmid. These exotoxins are ...
Infectious diseases - viral (AIDS, SARS, West Nile encephalitis, hepatitis, herpes, measles, others), bacterial (TB, typhoid, ... Toxins - alcohol, benzenes. *Intrinsic disorders - Fanconi's, Kostmann's, cyclic neutropenia, Chédiak-Higashi. *Immune ... They defend against bacterial or fungal infection. They are usually first responders to microbial infection; their activity and ...
Hydrogen sulfide is also a potent cellular toxin, blocking the cytochrome system and inhibiting cellular respiration. More ... Those with significant lower airway involvement may develop bacterial infection. Importantly, victims suffering body surface ... Specific pretreatments, drugs to prevent chemically induced lung injuries due to respiratory airway toxins, are not available. ... cells or human pulmonary alveolar epithelial cells to agents such as hydrogen peroxide or bleach produces a time and toxin-dose ...
... and the distribution of bacterial toxins. Massive infection is likely to result in death from a combination of system-wide ... perfringens type A strain and is known as alpha toxin. This alpha toxin is a lethal toxin and also known as phospholipase C ( ... Gas gangrene (also known as clostridial myonecrosis[1] and myonecrosis[2]) is a bacterial infection that produces gas in ... "Virulence studies on chromosomal alpha-toxin and theta-toxin mutants constructed by allelic exchange provide genetic evidence ...
... due to the differentiation of bacterial metabolites and toxins. Thus, tertiary dentin is deposited rapidly, with a sparse and ...
Activation and toxin release by eosinophils is therefore tightly regulated to prevent any inappropriate tissue destruction.[5] ... The binding of bacterial molecules to receptors on the surface of a macrophage triggers it to engulf and destroy the bacteria. ...
Urine culture is deemed positive if it shows a bacterial colony count of greater than or equal to 103 colony-forming units per ... medications and toxins.[47] Medications that commonly cause this problem include the chemotherapeutic agent cyclophosphamide ... Urinary tract infections are the most frequent bacterial infection in women.[17] They occur most frequently between the ages of ... Chronic prostatitis in the forms of chronic prostatitis/chronic pelvic pain syndrome and chronic bacterial prostatitis (not ...
When host cells die, either by programmed cell death (also called apoptosis) or by cell injury due to a bacterial or viral ... Activation and release of toxins by eosinophils are, therefore, tightly regulated to prevent any inappropriate tissue ... Gómez-Gómez L, Boller T (June 2000). "FLS2: an LRR receptor-like kinase involved in the perception of the bacterial elicitor ... Finlay BB, McFadden G (February 2006). "Anti-immunology: evasion of the host immune system by bacterial and viral pathogens". ...
It is also an excellent place for bacterial growth and food spoilage if it is not properly processed. One way this is measured ... Toxins, poisons, environment pollution. *Aflatoxin. *Arsenic contamination of groundwater. *Benzene in soft drinks ...
Duclaux E (1899). 》Traité de microbiologie: Diastases, toxines et venins》 [Microbiology Treatise: diastases, toxins and venoms] ... Fisher JF, Meroueh SO, Mobashery S (February 2005). "Bacterial resistance to beta-lactam antibiotics: compelling opportunism, ... "Molecular biology of bacterial bioluminescence". 》Microbiological Reviews》 55 (1): 123-42. PMC 372803. PMID 2030669 ...
Toxins. Some kinds of raw beans contain a harmful tasteless toxin, lectin phytohaemagglutinin, that must be removed by cooking ... There have been many outbreaks of disease from bacterial contamination, often by salmonella, listeria, and Escherichia coli, of ... Bacterial infection from bean sprouts. It is common to make beansprouts by letting some types of bean, often mung beans, ... Cooking beans, without bringing them to the boil, in a slow cooker at a temperature well below boiling may not destroy toxins.[ ...
A type of antimicrobial drug used in the treatment and prevention of bacterial infections.. apoptosis. A highly regulated form ... and the reaction of the host organism to the infectious agent and the toxins it produces. The variety of biological pathogens ... A lash-like appendage that protrudes from the cell body of certain bacterial and eukaryotic cells.. flavin adenine dinucleotide ... A membrane-bound organelle which is present in all plant and fungal cells and some protist, animal, and bacterial cells.. ...
If activated cytotoxic CD8+ T cells recognize them, the T cells secrete various toxins that cause the lysis or apoptosis of the ... or because of viral or intracellular bacterial infection. The fragments are then presented on the cell surface in the complex ... This includes parts (coats, capsules, cell walls, flagella, fimbriae, and toxins) of bacteria, viruses, and other ... named the hypothetical substances halfway between bacterial constituents and antibodies "substances immunogenes ou antigenes" ( ...
"The antimicrobial peptide cathelicidin protects the urinary tract against invasive bacterial infection". Nature Medicine. 12 (6 ... Cathelicidins serve a critical role in mammalian innate immune defense against invasive bacterial infection.[6] The ...
... es are caused by bacterial infection, parasites, or foreign substances. Bacterial infection is the most common cause.[8] ... They are usually caused by a bacterial infection.[8] Often many different types of bacteria are involved in a single infection. ... symptoms indicating bacterial illness throughout the body, or a health condition causing immunosuppression.[1] People who are ... with aspiration of pus confirming the diagnosis and availing for Gram stain and bacterial culture.[19] ...
Toxins, poisons, environment pollution. *Aflatoxin. *Arsenic contamination of groundwater. *Benzene in soft drinks ...
Bacterial vaginosis[edit]. Probiotic treatment of bacterial vaginosis is the application or ingestion of bacterial species ... If the strain under evaluation belongs to a species known to produce toxins in mammals, it must be tested for toxin production ... "Commentary by the Scientific Committee on Animal Nutrition on Data Relating to Toxin Production" (PDF). Scientific Opinion. ... One possible scheme for testing toxin production has been recommended by the EU Scientific Committee on Animal Nutrition.[118] ...
Biological Toxins[edit]. Main article: Toxin. *X - botulinum toxin A. *XR - partially purified botulinum toxin A ... Bacterial Biological Agents[edit]. Main article: Biological agent. *N - anthrax. *TR - anthrax ...
... various toxins, and digestive/metabolic enzymes obtained from slaughterhouses. In the 1950s, the Armour Hot Dog Co. purified 1 ... "Green fluorescent protein as a reporter for macromolecular localization in bacterial cells". Methods. 20 (1): 62-72. doi ...
a b c d R. N. Jinadasa, S. E. Bloom, R. S. Weiss, G. E. Duhamel: Cytolethal distending toxin: a conserved bacterial genotoxin ... J. M. DiRienzo: Uptake and processing of the cytolethal distending toxin by mammalian cells. In: Toxins. Band 6, Nummer 11, ... T. Faïs, J. Delmas, A. Serres, R. Bonnet, G. Dalmasso: Impact of CDT Toxin on Human Diseases. In: Toxins. Band 8, Nummer 7, 07 ... Cytolethal distending Toxin (Cdt, zu deutsch etwa ‚zelltödliches schwellendes Toxin') ist ein Protein aus verschiedenen Gram- ...
They may act as toxins.. Erythrocruorin. Found in many annelids, including earthworms, it is a giant free-floating blood ... "Biochemical and enzymological aspects of the symbiosis between the deep-sea tubeworm Riftia pachyptila and its bacterial ...
In the US, it is the second-most-common bacterial sexually transmitted infections; chlamydia remains first.[64][65] According ... Culture (growing colonies of bacteria in order to isolate and identify them) and Gram-stain (staining of bacterial cell walls ... "Bacterial conjunctivitis". BMJ Clinical Evidence. 2012. ISSN 1752-8526. PMC 3635545. PMID 22348418 ...
Bacterial toxins (such as botulinum neurotoxins, Shiga toxins, and staphylococcal enterotoxins) and their variants are ... 2010-2015: Technologies for Detecting and Determining the Bioavailability of Bacterial Toxins ... ARS Home » Pacific West Area » Albany, California » Western Regional Research Center » Foodborne Toxin Detection and Prevention ... New in vitro methodology is calibrated against animal bioassays, and the impact of food processing on toxin activity and ...
Bacterial protein toxins. [J E Alouf; Centre national de la recherche scientifique (France); Federation of European ... toxins> # Bacterial Toxins. a schema:Intangible ;. schema:name "Bacterial Toxins"@en ;. .. ... Bacterial toxins. a schema:Intangible ;. schema:name "Bacterial toxins"@en ;. .. ... Bacterial toxins. a schema:Intangible ;. schema:name "Bacterial toxins"@en ;. .. ...
... wall components of bacteria to interact with platelets has been well established there is also evidence that bacterial toxins ... Platelet Activation Necrotizing Fasciitis Toxic Shock Syndrome Bacterial Toxin Shiga Toxin These keywords were added by machine ... The Effect of Bacterial Toxins on Platelet Function. In: Kini R., Clemetson K., Markland F., McLane M., Morita T. (eds) Toxins ... Modeling the bacterial protein toxin, pneumolysin, in its monomeric and oligomeric form. J. Biol. Chem. 269, 25315-25320.PubMed ...
Purchase The Comprehensive Sourcebook of Bacterial Protein Toxins - 4th Edition. Print Book & E-Book. ISBN 9780128001882, ... Descriptions of relevant toxins as well as representative toxins of the main bacterial toxin families to allow for a better ... Section I: Basic Genomic and Physiological Aspects of Bacterial Protein Toxins 1. Evolutionary aspects of toxin-producing ... Section IV: Clinical Aspects, Applications of Bacterial Protein Toxins in Cell Biology and Therapy, and Toxin Inhibitors ...
Bacterial toxins inhibiting or activating small GTP-binding proteins.. Boquet P1. ... However, exoenzyme C3 is not a toxin, and chimeric proteins fusing C3 with the B moiety of either diphtheria toxin or ... Thus, Rho GTPases are targets for three different toxin activities. Molecular mechanisms of these toxins are discussed. ... C. difficile toxin B modifies by glucosylation Rho on T37 and Rac and Cdc42 on T35. Glucosylation of Rho, Rac, and Cdc42 blocks ...
The production of stable hybrid cell lines that secrete human monoclonal antibodies against bacterial toxins by fusing post- ... were positive for antibody to diphtheria toxin or tetanus toxin. Antibody to diphtheria toxin or tetanus toxin was detected in ... Because the human monoclonal antibodies against bacterial toxins, specifically exemplified by tetanus toxin and diphtheria ... Diphtheria toxin. Clostridium difficile. C. difficile toxin. Clostridium botulinum. Botulism toxin. Staphylococcus aureus. S. ...
glucosylating toxin families is to proteolytically cleave the toxin and release its cognate effector domains. The CPD becomes ... of toxin function by the CPD and the development of inhibitors to prevent CPD-mediated activation of bacterial toxins. ... This property allows the CPD to spatially and temporally regulate toxin activation, making it a prime candidate for developing ... Protease domains within toxins typically act as the primary effector domain within target cells. By contrast, the primary ...
A few molecules, at least of some toxins, are sufficient to change the cellular morphology and function of a cell or even kill ... Here, we review the development of immunotoxins and targeted toxins for the treatment of a disease that is still hard to treat ... In most cases, these toxins are extremely effective enzymes with high specificity towards their cellular substrates, which are ... Since many of those toxins are well studied concerning molecular mechanisms, cellular receptors, uptake routes, and structures ...
Our study has uncovered a bacterial protein that affects host cellular machinery in a sex-specific way, which is likely to be ... Male-killing toxin in a bacterial symbiont of Drosophila. *Toshiyuki Harumoto. 1. & ... Harumoto, T., Lemaitre, B. Male-killing toxin in a bacterial symbiont of Drosophila. Nature 557, 252-255 (2018). https://doi. ... Haselkorn, T. S. The Spiroplasma heritable bacterial endosymbiont of Drosophila. Fly (Austin) 4, 80-87 (2010). ...
... April 16, 2014 Dr. Klaus Aktories and Dr. Panagiotis Papatheodorou from the Institute of ... It is very similar to the toxins of many other hospital germs of the genus Clostridium. The toxins bind to surface molecules ... LRP1 is a receptor for Clostridium perfringens TpeL toxin indicating a two-receptor model of clostridial glycosylating toxins. ... The toxins force their way into host cells and deactivate signaling molecules by attaching a sugar molecule to these cellular ...
Cytolytic pore-forming toxins (PFTs) comprise ≈25% of all known bacterial protein toxins and act by forming pores at the plasma ... Mitogen-activated protein kinase pathways defend against bacterial pore-forming toxins. Danielle L. Huffman, Laurence Abrami, ... Mitogen-activated protein kinase pathways defend against bacterial pore-forming toxins. Danielle L. Huffman, Laurence Abrami, ... high levels of Cry5B toxin (100% Cry5B), low levels of Cry5B toxin (10% Cry5B), low levels of Cry21A toxin (0.1% Cry21A), ...
... capable of safely removing a broad class of dangerous toxins from the bloodstream, including toxins produced by MRSA, E. coli, ...
Life sciences/Microbiology/Bacteriology/Bacterial physiology/Bacterial defenses/Bacterial toxins * /Life sciences/Microbiology/ ... A bacterial toxin turning cells into swiss cheese Researchers from Kanazawa University purified the pore-forming bacterial ... A bacterial toxin turning cells into swiss cheese. Kanazawa University. Journal. Frontiers in Immunology. Funder. , AMED, ... In a new study, researchers from Kanazawa University synthesized and characterized the bacterial toxin Monalysin to enable the ...
... October 25, 2017 You get an infection, you are given penicillin -- and then you could get ... give important insights in the pathobiology of antibiotic side reactions and unveil the multi-functionality of bacterial toxins ... Austrian scientists have now scrutinized the toxins biosynthetic pathway and presented the results in the journal Angewandte ... If the introduced unbalance leads to an overgrowth of bacteria producing toxins themselves, intestinal and metabolic disorders ...
Cholera toxin is an AB5 hexameric assembly secreted by Vibrio cholerae. As with many other bacterial toxins the catalytic ... The closely-related shiga toxin family comprises a number of toxins from Shigella dysenteriae and the `shiga-like toxins (also ... Toxin Project Publications. reference list Whos who in the toxin project * Faculty - Ethan Merritt, Christophe Verlinde, ... Why we are studying these toxins? Questions of basic science How does the toxin recognize and bind to the cell surface? How ...
Home / About / News / Scientists Learn Secrets of Deadly Bacterial Toxin Gun Scientists Learn Secrets of Deadly Bacterial Toxin ... An Up-Close View of Bacterial Motors , Viral Videos (and Bacterial Ones, Too) , Bacterial Syringe Necessary for Marine ... Developing new antibiotics that target different aspects of the bacterial cell, such as the type IV secretion system, would ... Artists depiction of a type IV secretion system nestled within a bacterial cell membrane. This structure shoots out thousands ...
One of the most potent toxins known acts by welding the two strands of the famous double helix together in a unique fashion ... So it is very important that we learn as much as we can about how these bacterial toxins work and how bacteria defend against ... Vanderbilt researchers unravel how bacterial toxin prevents DNA replication. *Download PDF Copy ... A team of Vanderbilt University researchers have worked out the molecular details that explain how this bacterial toxin -- ...
... Engineers at the University of California, San Diego ... the number of toxins each nanosponge could absorb depended on the toxin. For example, approximately 85 alpha-haemolysin toxin ... Unlike other anti-toxin platforms that need to be custom synthesized for individual toxin type, the nanosponges can absorb ... Red blood cells are one of the primary targets of pore-forming toxins. When a group of toxins all puncture the same cell, ...
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H17 is attributed in part to the bacterial factor verotoxin II (VTII), but the molecular mechanism of cell-death induction has ...
Amino acids of the bacterial toxin sopE involved in G nucleotide exchange on Cdc42. *Schlumberger M ... the Dbl-like eukaryotic G nucleotide exchange factors and the SopE-like toxins of pathogenic bacteria, which are injected into ...
... this toxin catalyzes the deamination of cytidines within double-stranded DNA, the researchers said. ... Home » Tools & Technology » Gene Silencing/Gene Editing » Bacterial Toxin Leads to CRISPR-Free Mitochondrial DNA Base Editing ... Bacterial Toxin Leads to CRISPR-Free Mitochondrial DNA Base Editing. Jul 08, 2020 ... Researchers from the Broad Institute and the University of Washington School of Medicine have discovered a bacterial toxin that ...
Biomedical and biotechnological research is yielding information and techniques that allows for the design of repurposed toxins ... Bacterial toxins can be repurposed. These diverse macromolecular complexes bind to human cells and transport enzymes across ... Repurposing Bacterial Toxins. Benjamin J Pavlik, University of Nebraska - Lincoln. Abstract. Bacterial toxins can be repurposed ... Pavlik, Benjamin J, "Repurposing Bacterial Toxins" (2017). ETD collection for University of Nebraska - Lincoln. AAI10682737. ...
Bacterial Infections. Bacillus anthracis Edema Toxin Increases Fractional Free Water and Sodium Reabsorption in an Isolated ... Generation and Characterization of Typhoid Toxin-Neutralizing Human Monoclonal Antibodies Typhoid toxin is a virulence factor ... This toxin has a unique A2B5 architecture with two active subunits, the ADP ribosyl transferase PltA and the DNase CdtB, linked ... Bacterial Infections. Transforming Growth Factor β1/SMAD Signaling Pathway Activation Protects the Intestinal Epithelium from ...
Release of lipid vesicle contents by the bacterial protein toxin alpha-haemolysin.. Ostolaza H1, Bartolomé B, Ortiz de Zárate I ... are treated with purified toxin. The results show that the toxin does not require of any membrane receptor to exert its ... alpha-Haemolysin is a protein toxin (107 kDa) secreted by some pathogenic strains of E. coli. It binds to mammalian cell ...
Ion Transport and Bacterial Toxins. Ann Intern Med. 1967;67:216-217. doi: 10.7326/0003-4819-67-1-216 ... The exact mechanisms by which bacterial toxins produce their effects are still poorly understood. One method of study has been ... Characterization of serum anti-diphtheria antibody activity following administration of equine anti-toxin for suspected ... to examine the effect of toxins on normal cellular processes such as the active transport of sodium and oxidative metabolism. ...
Toxin Epitopes Elicit Antibodies That Neutralize Cholera Toxin and STa Toxin and Inhibit Adherence of K88ac Fimbrial E. coli ... Comparison of Three Anthrax Toxin Neutralization Assays Miriam M. Ngundi, Bruce D. Meade, Tsai-Lien Lin, Wei-Jen Tang, Drusilla ... Anthrax Vaccine Precipitated Induces Edema Toxin-Neutralizing, Edema Factor-Specific Antibodies in Human Recipients Eric K. ... Genetic Fusions of Heat-Labile Toxoid (LT) and Heat-Stable Toxin b (STb) of Porcine Enterotoxigenic Escherichia coli Elicit ...
497e) Design of a Cholesterol-Binding Peptide to Inhibit Bacterial Toxin Activity. *Conference: AIChE Annual Meeting ... Our lab seeks to understand the mechanisms of bacterial toxin delivery to identify and exploit therapeutic targets. In this ... This project has demonstrated the utility of a cholesterol-binding peptide in inhibiting bacterial toxin activity, thus ... motif in the toxin that regulates the interaction of the toxin with cholesterol. Using this CRAC sequence, we designed a ...
Pore-Forming Toxins Induce Macrophage Necroptosis during Acute Bacterial Pneumonia.. Citation: PLoS pathogens. 2015-12-11; ... We report that diverse bacterial pathogens that produce a pore-forming toxin (PFT) induce necroptosis of macrophages and this ... N5/C10 protected alveolar macrophages, reduced bacterial burden, and lessened hemorrhage in the lungs. We conclude that ...
Home / Health and Medicine / LSUHSC research shows drug blocks enzyme that activates bacterial and viral toxins ... Lethal factor toxin cannot bind to PA that has not already been cut by furin; therefore, without cut PA, lethal factor toxin ... In anthrax, the lethal factor toxin must bind to another part of the anthrax toxin, called the PA molecule, before it can enter ... LSUHSC research shows drug blocks enzyme that activates bacterial and viral toxins. ...
  • Dr. Klaus Aktories and Dr. Panagiotis Papatheodorou from the Institute of Experimental and Clinical Pharmacology and Toxicology of the University of Freiburg have discovered the receptor responsible for smuggling the toxin of the bacterium Clostridium perfringens into the cell. (
  • It is very similar to the toxins of many other hospital germs of the genus Clostridium. (
  • Reference: LRP1 is a receptor for Clostridium perfringens TpeL toxin indicating a two-receptor model of clostridial glycosylating toxins. (
  • Here, the Clostridium botulinum C2 toxin enzymatic and translocation components were combined with the neurological targeting function of the C. botulinum serotype C1 binding component. (
  • The natural Clostridium botulinum C2 toxin was then delivered to human glioblastoma A172 and synchronized HeLa cells. (
  • 11 We have devised an alternative strategy for glycoprotein production that uses the toxin B glucosyltransferase from Clostridium difficile to produce site-specific homogeneous glucosylated proteins. (
  • The contribution of Clostridium difficile toxin A and B (TcdA and TcdB) to cellular intoxication has been studied extensively, but their impact on bacterial colonization remains unclear. (
  • Herein, we report that Giardia infection attenuates granulocyte tissue infiltration induced by intra-rectal instillation of Clostridium difficile toxin A and B in an isolate-dependent manner. (
  • Symptoms and timing of illness onsets are suggestive of a bacterial toxin, such as Bacillus cereus or Clostridium perfringens, according to public health officials. (
  • This review focuses on bacterial toxins such as Diphtheria toxin (DT), Pseudomonas exotoxin A (PE) and Clostridium perfringens enterotoxin (CPE). (
  • However, exoenzyme C3 is not a toxin, and chimeric proteins fusing C3 with the B moiety of either diphtheria toxin or Pseudomonas aeruginosa exotoxin A have been produced to intoxicate cells with low concentration of C3. (
  • Using the method, protective monoclonal antibodies against tetanus toxin and diphtheria toxin were produced that bind tetanus toxin and diphtheria toxin in vitro, respectively, and prevent tetanus and diphtheria in vivo in animals, respectively. (
  • We constructed SCF-based recombinant bacterial toxins by genetically fusing mutated form of natural ligand SCF to receptor binding deficient forms of Diphtheria toxin (DT) or Pseudomonas exotoxin A (ETA') and evaluated their efficacy in vitro. (
  • The toxins that inhibit protein synthesis, causing rapid cell death, at extremely low concentrations are diphtheria toxin (DT), Pseudomonas exotoxin A (ExoA), and Shiga toxin. (
  • The 50% lethal doses (LD 50 ) of staphylococcal alpha-toxin and beta-toxin, Pseudomonas exotoxin A and diphtheria toxin were 12 μg/g, 9 μg/g, 0.14 μg/g and 1.1 μg/g, respectively. (
  • Pathogenic bacteria produce numerous virulence factors, including protein toxins, to enhance their growth and survival within the host. (
  • Pore-forming toxins (PFT) are important virulence factors of many pathogenic bacteria [ 1 - 4 ], and there is a growing interest in innate defense mechanisms against PFT [ 4 , 5 ]. (
  • Many emerging and reemerging bacterial pathogens synthesize toxins that serve as primary virulence factors. (
  • Purified reagents have been used to sort out the mechanisms of bacterial disease by understanding how the virulence factors made by replicating pathogens alter the host. (
  • This research includes development of general strategies for treatment of toxin-mediated diseases, such as human monoclonal antibodies and novel antitoxin agents , and research on specific bacterial diseases in which toxins are the major virulence factors contributing to the manifestation of the disease. (
  • Also, toxins such as Shiga toxin, superantigens, gingipains and M proteins can activate platelets. (
  • Hyperproduction of alpha-toxin by Staphylococcus aureus results in paradoxically reduced virulence in experimental endocarditis: a host defense role for platelet microbicidal proteins. (
  • Bacterial toxins inhibiting or activating small GTP-binding proteins. (
  • Monalysin is secreted as an inactive pro-toxin, which is then activated by certain proteins called proteases. (
  • In this project, we have focused on a member of the repeats-in-toxin (RTX) family of proteins, which are secreted by many Gram negative bacteria, including Bordetella pertussis , Escherichia coli , and Aggregatibacter actinomycetemcomitans . (
  • Such proteins include a group of predicted interbacterial toxins of the deaminase superfamily, members of which have found application in gene-editing techniques. (
  • Instead of resembling other proteins that perform similar functions, however, the structure of teneurins most closely matches that of a bacterial toxin . (
  • The toxin was too tightly attached to be readily removed by chemical treatments that remove weakly bound macromolecules from proteins. (
  • An interesting, somewhat in between, situation is provided by pore-forming proteins, the best-characterized subclass of which are bacterial pore-forming toxins (PFTs). (
  • To deliver proteins with host cell-modulating activities, pathogenic bacteria either secrete protein toxins that are able to enter target cells autonomously, or use specialized secretion systems (type III, type IV or type VI secretion systems) to inject effector proteins directly into the host cell cytosol. (
  • The toxin cripples the action of "instructor" proteins, many of which share a common property - the ability to bind several actin molecules at once. (
  • The research team's previous work found that this particular bacterial toxin goes after the abundant actin proteins as opposed to the more-expected targeting of less-common molecules that send important cellular signals. (
  • Among many extracellular proteins, S. aureus strains also secrete a variety of potent toxins which include alpha hemolysin, enterotoxins, leukocidins, and exfoliative toxins, all of which are directly associated with particular disease manifestations. (
  • Bacterial strains possessing these constructs and functional TolA were tested for sensitivity against two group a colicins: A and N. Two such species, Chronobacter muytjensii and Yersinia enterocolitica complements the phenotype lacking functional TolA with their own encoded TolA proteins. (
  • ArtAB toxin of Salmonella enterica has components similar to those found in two different families: the ArtA (Q404H4) subunit is homologous with pertussis toxin A, while the ArtB (Q404H3) subunit is homologous with subB as well as proteins found in other Salmonella strains. (
  • Molecular mechanisms of these toxins are discussed. (
  • 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. (
  • One of the most potent toxins known acts by welding the two strands of the famous double helix together in a unique fashion which foils the standard repair mechanisms cells use to protect their DNA. (
  • The exact mechanisms by which bacterial toxins produce their effects are still poorly understood. (
  • Our lab seeks to understand the mechanisms of bacterial toxin delivery to identify and exploit therapeutic targets. (
  • The investigations of the mechanisms of host-pathogen interactions is a traditional field that keeps bringing new insights into eukaryotic biology, pathogenesis and mode of action of bacterial toxins and thus identifies potential targets for development of novel therapies. (
  • Furthermore, scaling relationships in our data upon changes in initial toxin concentration constrain the possible underlying mechanisms for assembly and reveal that the steps leading to the aerolysin heptamer are composed of at least seven independent reactions whose rates scale with toxin concentration. (
  • Bacterial persistence is recognized as one of the major mechanisms rendering resistance to antibiotics and relapsing infections during the treatment of infectious disease ( 2 , 4 ). (
  • Although persistence is a noninherited transient state of the bacterial life cycle, signaling pathways that enable bacterial persistence and the mechanisms that control persister formation are genetically encoded ( 4 - 6 ). (
  • Hence, taken altogether, our findings provide new insights into the comprehension of intracellular mechanisms involved in pain modulation, and indicate this bacterial protein toxin as a novel tool in the field of pain control. (
  • To accomplish this goal, the range of criteria used to demonstrate pathogenicity of an enteric bacterial toxin and potential mechanisms stimulating net intestinal secretion are reviewed. (
  • Sears, CL & Kaper, JB 1996, ' Enteric bacterial toxins: Mechanisms of action and linkage to intestinal secretion ', Microbiological Reviews , vol. 60, no. 1, pp. 167-215. (
  • I propose that bacterial pathogenicity is the result of multiple events in any given bacterium (vs. singular events) that occurred after the Fall and that no intentional pathogenic mechanisms exist. (
  • Staphylococcus aureus alpha-toxin attack on human platelets promotes assembly of the prothrombinase complex. (
  • Role of Staphylococcus aureus hemolytic toxin-alpha in pathogenesis of infectious endocarditis: studies in vitro. (
  • Escherichia coli α-hemolysin), Aeromonas hydrophila aerolysin, Staphylococcus aureus α-toxin, and Vibrio cholerae hemolysin. (
  • Li Qin et al, Toxin Mediates Sepsis Caused by Methicillin-Resistant Staphylococcus epidermidis, PLOS Pathogens (2017). (
  • PHILADELPHIA Researchers at the University of Pennsylvania School of Medicine have demonstrated that a bacterial toxin from the common bacterium Staphylococcus aureus shuts down the control mechanism of the tunnel, called an ion channel, in immune cell membranes. (
  • They found that α toxin produced by Staphylococcus aureus can worsen lung co-infection by Gram-negative bacteria by preventing acidification of bacteria-containing phagosomes, increasing proliferation, spread, and lethality. (
  • In a mixed-pathogen lung infection model, we find that the Staphylococcus aureus virulence factor α toxin potentiates Gram-negative bacterial proliferation, systemic spread, and lethality by preventing acidification of bacteria-containing macrophage phagosomes, thereby reducing effective killing of both S. aureus and Gram-negative bacteria. (
  • Pseudomonas aeruginosa Exotoxin A (PEA) and Staphylococcus aureus Alpha-Hemolysin (SAH), are highly cytotoxic and are promising moieties for bacterial cancer therapy. (
  • Staphylococcus aureus is a nonmotile, ubiquitous, gram-positive coccus which is a major human pathogen responsible for a wide range of infections, including skin and soft tissue infections, bacteremia, pneumonia, and several toxin-mediated diseases. (
  • 8. Staphylococcus aureus- some strains : (a) Toxic shock syndrome toxin-1. (
  • Toxic shock syndrome toxin (TSST) is a superantigen with a size of 22 kDa produced by 5 to 25% of Staphylococcus aureus isolates. (
  • Toxic shock syndrome toxin 1 (TSST-1), a prototype superantigen secreted by a Staphylococcus aureus bacterium strain in susceptible hosts, acts on the vascular system by causing inflammation, fever, and shock. (
  • 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. (
  • This project has demonstrated the utility of a cholesterol-binding peptide in inhibiting bacterial toxin activity, thus representing a novel anti-virulence strategy to treat bacterial infections. (
  • Bacterial infections still represent a threat to human health worldwide as major pathogens becoming resistant to all available antibiotics. (
  • 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. (
  • Even with modern antibiotics, septic shock from bacterial infections afflicts about 300,000 people a year in the U.S., with a mortality rate of 30 to 50 percent. (
  • As he also studies the role of blood clots in resisting infections, Armstrong decided to test the same techniques on blood clots that had been exposed to bacteria or to bacterial lipopolysaccharide. (
  • Recent studies have shown that in endemic countries where bacterial infectious diseases are common, Giardia infections can protect against the development of diarrheal disease and fever. (
  • Mouse study ties toxin to severity of blood infections. (
  • According to this new study, published in the Jan. 19, 2012, issue of Cell Host & Microbe , α-hemolysin, a toxin secreted by many strains of Escherichia coli ( E. coli ), may play an important, unexpected role during both the establishment and persistence of urinary tract infections. (
  • SOS-mediated induction of toxin synthesis also provides a mechanism that could exacerbate STEC infections and increase dissemination of stx genes. (
  • Instead of creating specific treatments for individual toxins, we are developing a platform that can neutralize toxins caused by a wide range of pathogens, including MRSA and other antibiotic resistant bacteria," said Zhang. (
  • We report that diverse bacterial pathogens that produce a pore-forming toxin (PFT) induce necroptosis of macrophages and this can be blocked for protection against Serratia marcescens hemorrhagic pneumonia. (
  • Prophylaxis or early treatment with a single α toxin neutralizing monoclonal antibody prevented proliferation of co-infecting Gram-negative pathogens and lethality while also promoting S. aureus clearance. (
  • Is the Subject Area "Bacterial pathogens" applicable to this article? (
  • Polymorphonuclear leukocytes or neutrophils (PMNs) are granulocytic, innate immune cells characteristic of acute intestinal inflammatory responses against bacterial pathogens that contribute to the development of diarrheal disease following recruitment into intestinal tissues. (
  • Many pathogens and their toxins have evolved to hijack cell entry systems, initiating endocytosis following the binding of sugars on the plasma membrane. (
  • The potential applications of toxin research extend beyond simply combating microbial pathogens and include use as novel anti-cancer drugs and other front-line medicines and as tools in neurobiology. (
  • The primary goal of this review is to critically assess the linkage between the mechanism of action of toxins produced by human enteric pathogens and the stimulation of intestinal secretion. (
  • A paper published in the December, 2002 issue of Infection and Immunity by a research team at the Louisiana State University (LSU) Health Sciences Center in New Orleans provides clear evidence that the lethal toxins of such infectious bacteria as Pseudomonas and anthrax can be blocked by a drug developed at the LSU Health Sciences Center in New Orleans. (
  • The B domain has either five subunits, which are identical in Shiga toxin, CT, and E. coli LT-I and LT-II and different in size and sequences in PT, or two subunits, the translocation (T) and the receptor-binding (R) subunits, in DT, Pseudomonas exotoxin A, botulinum toxin, and tetanus toxin. (
  • The same platform was also tested for bacterial detection including Pseudomonas aeruginosa and Escherichia coli spiked in water samples from a WTP. (
  • Bacterial toxins (such as botulinum neurotoxins, Shiga toxins, and staphylococcal enterotoxins) and their variants are characterized using these detection systems. (
  • The cholera toxin family includes in addition to cholera toxin itself the E. coli heat-labile enterotoxins LT and LT-II. (
  • Cholera toxin and related enterotoxins of gram-negative bacteria, ed. (
  • Domain A1 (approximately 22kDa in cholera toxin or heat labile enterotoxins) is the part of the toxin responsible for its toxic effects. (
  • The closely-related shiga toxin family comprises a number of toxins from Shigella dysenteriae and the `shiga-like' toxins (also known as verotoxins) from E. coli . (
  • The effect of these toxins on human populations ranges from the relatively mild travelers' diarrhea caused by infection with E. coli strains producing LT to the acute and life-threatening diarrhea caused by V. cholerae infection and the equally serious hemolytic uremic syndrome (`hamburger disease') caused by members of the shiga toxin family. (
  • The A subunit is divided into the enzymatically active A1 domain and the A2 linker domain in Shiga toxin, CT, E. coli LT-I and LT-II, and PT. (
  • Toxin synthesis by Shiga toxin-producing Escherichia coli (STEC) appears to be coregulated through induction of the integrated bacteriophage that encodes the toxin gene. (
  • Shiga toxin, also known as Stx, is a toxin that is produced by the rod shaped Shigella dysenteriae and Escherichia coli (STEC). (
  • The discovery of shiga toxin is credited to Dr. Kiyoshi Shiga in 1898. (
  • For Shiga toxin family, the A subunit hosts a Trypsin-sensitive region which gives out two fragmented domains when cleaved. (
  • On day 0 and day 2, pertussis toxin (100 ng/mouse, List Biological Labs ) was injected intraperitoneally. (
  • Author did not specify which List Labs Pertussis Toxin was utilized. (
  • Pertussis toxin is secreted by the gram-negative bacterium, Bordetella pertussis. (
  • 1. A continuous cell line which produces human anti-exotixin antibodies, comprising: a stable fused cell hybrid of a human peripheral blood lymphocyte immunized by a toxin, or an imunogenic fragment thereof, or a toxoid prepared from an exotoxin, or an immunogenic fragment thereof, and a mouse myeloma cell, in which the antibodies are capable of neutralizing exotoxin. (
  • Exotoxin (alpha toxin) has lacithinase activity and thereby causes cell death, (b) Enterotoxin causes hyper secretion of water and electrolytes in diarrhoea. (
  • TSST-1 is a bacterial exotoxin found in patients who have developed toxic shock syndrome (TSS), which can be found in menstruating women or any man or child for that matter. (
  • Staphylococcal alpha toxin. (
  • Effect of staphylococcal and other bacterial toxins on platelets in vitro . (
  • Staphylococcal alpha-toxin, streptolysin-O, and Escherichia coli hemolysin: prototypes of pore-forming bacterial cytolysins. (
  • A culture-supernatant of a disruption mutant of the S. aureus beta-toxin gene did not kill larvae, whereas one of a deletion mutant of alpha-toxin, gamma-toxin, or aureolysin killed larvae, indicating that the beta-toxin gene is required for staphylococcal supernatant-mediated killing of silkworm larvae. (
  • b) Staphylococcal enterotoxin causes toxin type food poisoning and stimulates vomiting centre of brain. (
  • Tissue destruction that occurs upon infection with the bacterium Escherichia coli 0157:H17 is attributed in part to the bacterial factor verotoxin II (VTII), but the molecular mechanism of cell-death induction has not been clear. (
  • Cytotoxic Necrotizing Factor 1 (CNF1) is a protein toxin from Escherichia coli that constitutively activates the Rho, Rac and Cdc42 GTPases. (
  • In most cases, these toxins are extremely effective enzymes with high specificity towards their cellular substrates, which are often central signaling molecules. (
  • The toxins force their way into host cells and deactivate signaling molecules by attaching a sugar molecule to these cellular switches. (
  • By using microarrays, we demonstrate that the nematode Caenorhabditis elegans responds robustly to Cry5B, a member of the pore-forming Crystal toxin family made by Bacillus thuringiensis . (
  • The pores formed by these toxins can vary in effective diameter from 1-2 nm [e.g., α-toxin, hemolysin, aerolysin, and Bacillus thuringiensis (Bt) Crystal (Cry) toxins (see below)] to 25-30 nm (e.g., streptolysin O). (
  • Determination of some bacteria toxins associated with contact lenses (CL) after different using periods (0, 1, 5, 10 and 15 Days) with immuno-Tecra technique Bacterial toxin Usage periods of contact lenses (day) 0 1 Bacillus spp. (
  • In addition to mACs, bacterial AC toxins such as edema factor (EF) from Bacillus anthracis and CyaA from Bordetella pertussis have also been identified. (
  • Biomedical and biotechnological research is yielding information and techniques that allows for the design of repurposed toxins by "shuffling" the components of AB-type binary exotoxins toxins. (
  • Role of exotoxins in bacterial pathogenicity. (
  • Neutrophils undergo rapid constitutive apoptosis that is accelerated following bacterial ingestion as part of effective immunity, but is also accelerated by bacterial exotoxins as a mechanism of immune evasion. (
  • Bacterial toxins are exotoxins and endotoxins. (
  • Several pathogenic bacteria secrete toxins to inhibit the immune system of the infected organism. (
  • Although PFTs are important to the virulence of many pathogenic bacteria, there is little understanding, apart from physiological data, as to how cells respond to these toxins and whether they mount a defense. (
  • There are at least two known families of guanine nucleotide exchange factors that can activate RhoGTPases: the Dbl-like eukaryotic G nucleotide exchange factors and the SopE-like toxins of pathogenic bacteria, which are injected into host cells to manipulate signaling. (
  • The AB5 toxins are six-component protein complexes secreted by certain pathogenic bacteria known to cause human diseases such as cholera, dysentery, and hemolytic-uremic syndrome. (
  • The production of stable hybrid cell lines that secrete human monoclonal antibodies against bacterial toxins by fusing post-immunization human peripheral blood lymphocytes with nonsecretor mouse myeloma cells is described. (
  • In tissue studies using S. epidermidis strains, the group found that the PSM-mec toxin helped the bacteria survive in human blood and resist attack by neutrophils, important immune system fighters. (
  • Novel recombinant toxins are already proposed in the treatment of some diseases, as well as new vaccines. (
  • An antigen may be a recombinant or native protein, partial protein, synthetic or natural peptide, chemical, toxin, viral or bacterial component, standard or reagent for ELISA assays, as well as an environmental agent. (
  • Bacterial toxins are involved in the pathogenesis of many bacteria, some of which are responsible for severe diseases in human and animals, but can also be used as tools in cell biology to dissect cellular processes or used as therapeutic agents. (
  • 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. (
  • Our study has uncovered a bacterial protein that affects host cellular machinery in a sex-specific way, which is likely to be the long-searched-for factor responsible for S. poulsonii -induced male killing. (
  • Mammalian cells are not affected by these toxins because they lack cellular receptors that allow binding ( 6 ). (
  • We show that two mitogen-activated protein kinase (MAPK) pathways [p38 and c-Jun N-terminal kinase (JNK)-like] are transcriptionally up-regulated by the toxin, that both of these MAPK pathways provide a significant cellular defense against the toxin, and that this defense is conserved in mammalian cells attacked by a PFT. (
  • Most current antibiotics focus on destroying the cellular envelope that encompasses a bacterial cell, preventing it from replicating,' says Jensen. (
  • The nanosponges absorb damaging toxins and divert them away from their cellular targets. (
  • 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. (
  • Based on the observation that target cells of PFT may recover from a substantial drop of cellular ATP, we have advanced the concept that the repair of membrane lesions is an important aspect of cellular defense against these toxins [ 12 - 14 ]. (
  • Recent work on Vibrio cholerae cytolysin (VCC) indicated that autophagy may play a role in the cellular defense against this toxin [ 17 ]. (
  • We present a cellular logic circuit for deciphering the profiles of toxin production in B. cereus, using multiple readout techniques based on the pore formation on the cell membrane. (
  • It's a significant addition to the short list of defenses that animals use to protect themselves against toxin-induced sepsis," said Peter Armstrong, professor of molecular and cellular biology at UC Davis and senior author on the paper. (
  • The activation of the toxin is often coupled to the induction of cellular response pathways, such as the stringent response, in response to multiple stress conditions. (
  • In the field of cellular biology, toxins have become invaluable as tools for the manipulation and investigation of fundamental cellular and physiological processes. (
  • This timely volume serves as an update on the most important recent advances in the genetics, cellular biology and practical applications of the most important bacterial toxins. (
  • The study focused on how one bacterial toxin called ACD (a type linked to cholera and poisoning by raw oysters) modifies an abundant cellular protein called actin and converts it into a secondary toxin. (
  • The toxin is then redirected toward less-abundant targets, which leads to a cascade of cellular changes that break down normal function. (
  • Ultimately the response of platelets to infection is likely to be due to both direct interaction with bacteria and exposure to secreted bacterial products. (
  • Developing a drug that would disable even one core protein component of the secretion system, Ghosal says, would enable human cells to fight back against the bacterial infection. (
  • The lipid A core of bacterial endotoxin activates the immune system and can cause septic shock, a major cause of death from infection. (
  • It could also prove useful in treating infection from other viruses and bacteria whose toxins are dependent upon furin activity for activation. (
  • It is now well-accepted that this potent bacterial toxin plays an important role in producing necrotizing fasciitis (NF), the rapid infection of soft tissue referred to as flesh-eating" disease. (
  • In a mouse model, the toxin significantly increased disease and stimulated the immune response, which worsened the septic infection. (
  • Notably, PKR, an eIF2α-kinase which has been implicated in autophagy induction during viral infection, was also activated upon membrane perforation, and evidence was obtained that phosphorylation of eIF2α is required for the accumulation of autophagosomes in α-toxin-treated cells. (
  • These studies suggest that some pathogen-specific, antibody-based approaches may also work to reduce infection risk in patients colonized or co-infected with S. aureus and disparate drug-resistant Gram-negative bacterial opportunists. (
  • Giardia duodenalis infection reduces granulocyte infiltration in an in vivo model of bacterial toxin-induced colitis and attenuates inflammation in human intestinal tissue. (
  • Following infection, the AC toxins cause a dramatic increase in cAMP levels, thereby disrupting several intracellular signaling pathways. (
  • Many of these organisms have been reported to produce one or more toxins postulated as important in the pathogenesis of the diarrhea resulting from infection with the organism. (
  • Food and drinks contaminated with these bacteria are the source of infection and how this toxin is spread. (
  • Essential reading for everyone with an interest in bacterial toxins and recommended book for researchers interested in microbial genomics and microbial pathogenesis. (
  • 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. (
  • Our discovery will also provide new impetus for researchers to identify further toxin receptors," Aktories hopes. (
  • Membrane receptors for bacterial toxins. (
  • Taken together, the data suggest that toxin-mediated modulation of host cell organization may account for the capacity of this opportunistic pathogen to gain access to BL receptors, leading to a successful colonization of the colonic mucosa. (
  • Toxins 2017 , 9 , 236. (
  • 2017. "Bacterial Toxins for Cancer Therapy. (
  • Pavlik, Benjamin J, "Repurposing Bacterial Toxins" (2017). (
  • Importantly, the peptide is able to inhibit the activity of unrelated cholesterol-binding toxins, including streptolysin and pneumolysin, indicating the broad activity of the peptide. (
  • Bacterial cells utilize toxin-antitoxin systems to inhibit self-reproduction, while maintaining viability, when faced with environmental challenges. (
  • They also are investigating whether related toxins found in methicillin-susceptible S. epidermidis and S. aureus have a similar function. (
  • Here, we show that S. aureus α-toxin, Vibrio cholerae cytolysin, streptolysin O and E. coli haemolysin activate two pathways leading to autophagy. (
  • Treatment with 3-methyl-adenine inhibited autophagy and disrupted the ability of cells to recover from sublethal attack by S. aureus α-toxin. (
  • that p38 MAPK is important for the survival of C. elegans exposed to PFT-producing bacteria or of mammalian cells incubated with aerolysin [ 6 ], we found that p38 is required at an early stage after sublethal attack by S. aureus α-toxin to promote metabolic recovery of the target cell. (
  • However, early treatment or prophylaxis with a neutralizing antibody to α toxin prevented this effect and promoted S. aureus clearance in a humanized mouse model. (
  • They are expressed by S. aureus during logarithmic growth and shut off expression once a certain bacterial density is reached. (
  • Cholera toxin is an AB 5 hexameric assembly secreted by Vibrio cholerae . (
  • The receptor for cholera toxin and heat-labile enterotoxin is ganglioside GM1. (
  • The structure of the cholera toxin B-pentamer complexed with the complete GM1 pentasaccharide [1994a, 1997d, 1998d] gives us a view of the toxin:receptor binding mode at atomic resolution. (
  • The sub-populations of neurones labelled by B subunits of cholera toxin (CTB) and the related heat-labile enterotoxin (LTB) following various routes of injection in mice were studied. (
  • Cholera toxin is composed of a protein complex that is secreted by the bacterium Vibrio cholerae. (
  • The toxin shares its mechanism with cholera toxin. (
  • Domain A2 (approximately 5kDa in cholera toxin or heat labile enterotoxin) provides a non-covalent linkage to the B subunit through the B subunit's central pore. (
  • The A1 chain for cholera toxin catalyzes the transfer of ADP-ribose from Nicotinamide adenine dinucleotide(NAD) to arginine or other guanidine compounds by utilizing ADP-ribosylation factors (ARFs). (
  • Thus, we evaluated the role of this TA system in X. fastidiosa by overexpressing the MqsR toxin, and verified that the toxin positively regulated biofilm formation and negatively cell movement, resulting in reduced pathogenicity in citrus plants. (
  • Toxins are virulence determinants that play an important role in microbial pathogenicity and/or evasion of the host immune response. (
  • A creation model of the origin of bacterial pathogenicity will be developed based on the findings. (
  • This procedure led to the discovery that cells are immune to the TpeL toxin when the gene for the protein LRP1 is switched off on the cell surface. (
  • image: Researchers from Kanazawa University developed a novel tool to study how the innate immune system fights bacterial toxins. (
  • In a new study, researchers from Kanazawa University synthesized and characterized the bacterial toxin Monalysin to enable the study of how the innate immune system and toxin-producing bacteria interact with each other. (
  • Our findings could help understand how the innate immune system fights off bacteria that produce pore-forming toxins. (
  • Because these toxins stimulate the mucosal immune system, there is great interest in using an engineered form of the toxin as a basis for the design of vaccines against a wide range of diseases. (
  • In order to use the toxin as a vaccine component it is obviously desirable to reduce or abolish the cytotoxicity while retaining the toxins ability to stimulate the immune system. (
  • The leukotoxin (LtxA) secreted by A. actinomycetemcomitans specifically kills human white blood cells to disrupt the host immune response and therefore plays a key role in bacterial colonization of the host. (
  • Using this CRAC sequence, we designed a cholesterol-binding peptide that inhibits LtxA-mediated cytotoxicity of human immune cells by blocking the binding of the toxin to cholesterol. (
  • Gladue, "Linezolid effects on bacterial toxin production and host immune response: review of the evidence," Current Therapeutic Research- Clinical and Experimental, vol. (
  • In this case the bacterial toxins , which cause the immune response, are more likely to be from gram-negative bacteria. (
  • Severe bacterial sepsis is characterized by an extreme immune response, inflammation, reduced blood flow, clotting, and organ failure. (
  • Bacterial toxin closes gate on immune response, Penn researcher. (
  • Shutting down ion channels has long been known to suppress the immune response, and the bacteria may use the toxin to neutralize host defenses against bacteria. (
  • These disruptions of the normal immune response to bacterial invasion may help to explain why UTIs can persist or recur, even in otherwise healthy individuals and in the presence of antibiotics. (
  • In theory, the actin's abundance within every single human cell should make it a difficult to disable - and disabling targets is the business of a bacterial toxin looking to gum up the immune system and make a human or animal sick. (
  • Considerable progress has been made in understanding the structure, function, interaction and trafficking into cells, as well as mechanism of action of toxins. (
  • Consistently, membrane lesions formed by streptolysin O (SLO) are reportedly internalized by a dynamin-independent mechanism [ 15 ], whereas those caused by α-toxin are eliminated by dynamin-dependent endocytosis and subsequent exocytosis [ 16 ]. (
  • In this study, we report a new mechanism by which a toxin-antitoxin system responds to harsh environmental conditions or nutrient deprivation by orchestrating a dormant state while preserving viability. (
  • Analysis of the gene and protein expression showed that this system likely has an autoregulation mechanism to express the toxin and antitoxin in the most beneficial ratio for the cell to oppose stress. (
  • Partly this is due to questions about their mechanism of action and the presumption that anti-bacterial agents have no obvious connection to killing mammalian tumor cells. (
  • All of these toxins share a similar structure and mechanism for entering targeted host cells. (
  • 3. A continuous cell line which produces human anit-tetanus toxin antibodies, comprising: a stable fused cell hybrid of a tetanus toxin-immunized or toxoid-immunized human peripheral blood lymphocyte and a mouse myeloma cell, in which the anitbodies are capable of neutralizing tetanus toxin. (
  • They purified the pore-forming toxin Monalysin from a bacterial culture, and structurally and functionally characterized the purified toxin to show how it functions at the molecular level. (
  • Now, for the first time, Caltech scientists have created a 3-D image of a molecular structure that many different bacteria use to pump toxins into human cells and spread antibiotic-resistance genes to other bacteria. (
  • A team of Vanderbilt University researchers have worked out the molecular details that explain how this bacterial toxin -- yatakemycin (YTM) -- prevents DNA replication. (
  • Unlike other anti-toxin platforms that need to be custom synthesized for individual toxin type, the nanosponges can absorb different pore-forming toxins regardless of their molecular structures. (
  • Computer model showing the molecular structure of the bacterial toxin pneumolysin. (
  • The molecular weight of LTNF is 63 kDa, and it does not form precipitation with venoms or toxins by immunodiffusion. (
  • The device characterizations, semiconducting properties and use in a robust and sensitive bio-molecular detection sensor of bacterial toxins were reported in this work. (
  • This property allows the CPD to spatially and temporally regulate toxin activation, making it a prime candidate for developing anti-toxin therapeutics. (
  • Characterization of serum anti-diphtheria antibody activity following administration of equine anti-toxin for suspected diphtheria. (
  • C. sordellii lethal toxin modifies Ras, Rap, and Rac on T35 by glucosylation. (
  • Anti-lethal factor named Lethal Toxin Neutralizing Factor (LTNF) has been isolated in purity from opossum ( Didelphis virginiana ) serum by high pressure liquid chromatography (HPLC). (
  • Opossum, Didelphis virginiana, lethal toxin neutralizing factor. (
  • Pore-Forming Toxins Induce Macrophage Necroptosis during Acute Bacterial Pneumonia. (
  • It has been shown that a clinically relevant trigger, γ-radiation, can induce gene expression using the recA promoter, a component from the bacterial SOS system. (
  • The toxin-antitoxin (TA) systems are involved in the formation of persister cells because they are able to induce cell dormancy. (
  • We report that pore-forming toxins (PFTs) induce respiratory epithelial cell necroptosis independently of death receptor signaling during bacterial pneumonia. (
  • 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. (
  • This toxin has a unique A2B5 architecture with two active subunits, the ADP ribosyl transferase PltA and the DNase CdtB, linked to a pentameric B subunit, which is alternatively made of. (
  • This acute pediatric renal disease, defined by the triad of thrombocytopenia, glomerular endothelial damage and hemolytic anemia is mediated by toxin B subunit pentamer binding to its receptor glycosphingolipid, globotriaosyl ceramide (Gb 3 ) within lipid rafts in the glomerular endothelial cell plasma membrane and the subsequent endothelial pathology. (
  • A section shows the subunit composition and the spatial organization of toxins whose structures have been solved either by X-ray crystallography or by quick-freeze deep-etch electron microscopy. (
  • The A subunit of an AB5 toxin is the portion responsible for catalysis of specific targets. (
  • Bacterial toxin vaccines. (
  • Engineers at the University of California, San Diego, have invented a 'nanosponge' capable of safely removing a broad class of dangerous toxins from the bloodstream, including toxins produced by MRSA, E. coli , poisonous snakes and bees. (
  • This is a new way to remove toxins from the bloodstream," said Liangfang Zhang, a nanoengineering professor at the UC San Diego Jacobs School of Engineering and the senior author on the study. (
  • She fell victim to septic shock after bacterial toxins invaded her bloodstream. (
  • Now, National Institutes of Health (NIH) scientists have identified an S. epidermidis toxin (PSM-mec) that is released into the bloodstream and contributes to sepsis. (
  • Bacterial Toxins and Targeted Brain Therapy: New Insights from Cytotoxic Necrotizing Factor 1 (CNF1). (
  • Toxin B realizes its cytotoxic effects by inactivating small GTPases through α-glucosylation of conserved active-site threonine residues. (
  • Using this system allows future development of bacterial protein delivery to include highly cytotoxic bacterial toxins. (
  • They discovered that paxillin degradation was stimulated by α-hemolysin (HlyA), a toxin secreted by UPEC, which inserts into bladder cell membranes. (
  • These nanosponges, which thus far have been studied in mice, can neutralize "pore-forming toxins," which destroy cells by poking holes in their cell membranes. (
  • Scientists have known for about a decade that defensins can neutralize bacterial toxins but, until now, did not know how. (
  • Some type IV secretion systems are thought to be instrumental in spreading antibiotic-resistance genes throughout the bacterial population. (
  • Artist's depiction of a type IV secretion system nestled within a bacterial cell membrane. (
  • 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. (
  • GM1 is a normal membrane component which the toxin coopts as a receptor. (
  • The toxin recognizes the branched pentasaccharide portion of GM1 which protrudes from the exterior membrane surface. (
  • The research team, that included Yanping Xu, MD, PhD and Yajamana Ramu, PhD, showed that removal of phosphate head groups from some membrane lipids by the bacterial toxin called sphingomyelinase (SMase) C shuts down the Kv1.3 channel. (
  • The first observable responses of the epithelial cells to these compounds are changes in metabolism for one toxin (warfarin) and alterations in membrane permeability for another (gliotoxin). (
  • The other four toxins display a similar time course in response as gauged by changes in metabolism and loss of membrane integrity. (
  • In particular pore-forming toxins such as pneumolysin, streptolysins and a-toxin can activate platelets probably in a manner similar to the calcium ionophore A23187. (
  • Pneumolysin is a pore forming toxin (PFT) produced by the bacteria Streptococcus pneumoniae (pneumococcus). (
  • This strongly hints that reduction of the disulfide bond is a crucial step in activation of the toxin. (
  • Streptococcus pyogenes streptolysin O), repeats in toxin cytolysins (e.g. (
  • Given the multifaceted aspects of toxin research and the multidisciplinary approaches adopted, toxins are of great interest in many scientific areas from microbiology, virology, cell biology to biochemistry and protein structure. (
  • Working on the theory that if the action of furin could be blocked, the toxins would not be activated and therefore unable to kill cells, the research team set out to make a peptide that would suppress furin activity. (
  • Using a MALDI-MS based assay, the kinetic parameters for peptide glucosylation using the C. difficile toxin B glycosyltransferase domain were determined. (
  • 14 Here, we report the discovery and characterization of a nine amino acid peptide substrate for the toxin B glucosyltransferase domain (GTD) and its applications as a protein tag for site-specific and homogenous glycoprotein engineering ( Fig. 1 ). (
  • Fig. 1 Glucosylation of peptide consensus on a protein of interest (POI) with C. difficile toxin B. (
  • 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. (
  • When this approach is combined with the intermediates of bacterial O -antigen biosynthesis the resulting conjugates are valuable as potential anti-bacterial vaccine components. (
  • Its illustration of the way antibiotics leave bacterial toxins in the gut also shows just why it is so important to take probiotics after a course of antibiotics. (
  • It is no secret that antibiotics kill the good bacteria in our bodies along with the bad bacteria because they are unable to distinguish between the two, and when you consider the fact that they're potentially leaving bacterial toxins behind, it becomes clear just how important it is to bring balance back to the gut after taking these medications. (
  • Three-domain Cry toxins made by Bt are also PFTs, but these target insects and nematodes ( 5 ). (
  • The role of PFTs is unlikely to be rapid cell lysis, because most mammalian cells do not rapidly swell and lyse when treated with low (physiological) concentrations of PFTs but rather stay viable for many hours (the toxins are, however, cytolytic at higher concentrations) ( 1 ). (
  • For this reason bacterial PFTs have been studied extensively during the last century and a lot of insight into their mode of action has been gained. (
  • 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. (
  • The researchers demonstrate that LRP1 is the long sought-after key molecule: It also regulates the intake of the toxin TpeL. (
  • By reacting the purified toxin with Drosophila cells, the researchers confirmed its toxic effect when cell viability dropped significantly as more pro-Monalysin was added to the cells. (
  • The researchers conducted a series of experiments to characterize one of those toxins, called IpaJ, chosen in part because so little was known about the protein. (
  • Based on its genetic sequence, researchers had an inkling that teneurins resembled bacterial toxins, poison molecules bacteria use to attack and comprise host cells. (
  • The researchers wanted to better understand how a relatively small amount of bacterial toxin could do such swift, significant damage to a strong network of actin. (
  • Dr. Lindberg was recently awarded a grant by the National Institute of Allergy and Infectious Diseases to test D6R against anthrax toxin in both cells as well as animal models (rats and mice). (
  • If the introduced unbalance leads to an overgrowth of bacteria producing toxins themselves, intestinal and metabolic disorders can follow. (
  • How toxin activation triggers persistence and induces a systemic stress response in the alphaproteobacteria remains unclear. (
  • Here, we present an evaluation of the sensitivity of two immortal cell lines (A549, human lung carcinoma epithelia) and NR8383 (rat alveolar macrophages) to a variety of bacterial-derived inhalation hazards and simulants including etoposide, gliotoxin, streptolysin O, and warfarin. (
  • Throughout this review, emphasis has been given to data derived from studies of toxins in potentially relevant models of disease, namely intestinal mucosa in vivo and/or intestinal epithelial cells in vitro. (
  • X-ray crystallographic and structure-function data indicate that, for Cry toxins, pore-formation is associated with the N-terminal domain (domain I) that is comprised of seven conserved α-helices, two of which, α4 and α5, are likely to form the pore ( 7 ). (
  • In particular it is unknown whether oligomerization occurs through the sequential addition of monomers or through interaction of multimeric intermediates, whether oligomerization is the rate-limiting step during the pore-formation process and whether the same rules apply to all toxins. (
  • In fact, analysis of the stochasticity of the processes led to the robust determination for each toxin of the minimal number of independent rate-limiting steps required for pore formation. (
  • C. difficile toxin B modifies by glucosylation Rho on T37 and Rac and Cdc42 on T35. (