cholera toxin


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Related to cholera toxin: Vibrio cholerae

toxin

 [tok´sin]
a poison, especially a protein or conjugated protein produced by certain animals, higher plants, and pathogenic bacteria. Bacterial toxins characteristically do not cause symptoms until after a period of incubation while the microbes multiply, or (as happens with botulism) the preformed toxin reaches and affects the tissue. Usually only a few toxin-producing agents are introduced into the body, and it is not until there are enough of them to overwhelm the leukocytes and other types of antibodies that symptoms occur. In some cases of food poisoning, symptoms are almost immediate because the toxin is taken directly with the food. Toxins can cause antitoxins to form in the body, thus providing a means for establishing immunity to certain diseases.
bacterial t's toxins produced by bacteria, including exotoxins, endotoxins, enterotoxins, neurotoxins, and toxic enzymes. See also toxin.
botulinal toxin (botulinum toxin) (botulinus toxin) one of seven type-specific, immunologically differentiable exotoxins (types A to G) produced by Clostridium botulinum,neurotoxins usually found in imperfectly canned or preserved foods. They cause botulism by preventing release of acetylcholine by the cholinergic fibers. Type A is one of the most powerful poisons known; it is also used therapeutically by injection to inhibit muscular spasm in the treatment of dystonic disorders such as blepharospasm and strabismus, to treat wrinkles of the upper face, and to reduce anal sphincter pressure to promote healing of chronic anal fissure. Type B is injected in treatment of cervical dystonia. Called also botulin.
cholera toxin an exotoxin produced by Vibrio cholerae; a protein enterotoxin that binds to the membrane of enteric cells and stimulates the adenylate cyclase system, causing the hypersecretion of chloride and bicarbonate ions, resulting in increased fluid secretion and the severe diarrhea characteristic of cholera.
clostridial toxin one elaborated by species of Clostridium, including those causing botulism (botulinus toxin), gas gangrene (gas gangrene toxin), and tetanus (tetanus toxin). In addition, C. difficile produces an exotoxin causing severe intestinal necrosis and C. perfringens produces exotoxins causing gas gangrene, intestinal necrosis, hemolysis, cardiotoxicity, and deoxyribonuclease and hyaluronidase activity, as well as an enterotoxin causing food poisoning.
Dick toxin erythrogenic toxin.
diphtheria toxin a protein exotoxin produced by Corynebacterium diphtheriae that is primarily responsible for the pathogenesis of diphtheria and related infections; it is an enzyme that activates transferase II of the mammalian protein synthesizing system.
diphtheria toxin for Schick test a sterile solution of the diluted, standardized toxic products of Corynebacterium diphtheriae; used as a dermal reactivity indicator in the schick test of immunity to diphtheria.
dysentery toxin any of various exotoxins produced by species of Shigella; the one formed by S. dysenteriae serotype 1 is a potent neurotoxin with hemorrhagic and paralytic properties.
erythrogenic toxin a bacterial toxin from certain strains of Streptococcus pyogenes that produces an erythematous reaction when injected intradermally and is responsible for the rash in scarlet fever.
extracellular toxin exotoxin.
gas gangrene toxin an exotoxin that causes gas gangrene; there are at least 10 types produced by Clostridium perfringens and others produced by C. noriyi and C. septicum.
streptococcal toxin a mixture of exotoxins formed by Streptococcus pyogenes.
tetanus toxin the potent exotoxin produced by Clostridium tetani, consisting of two components, one a neurotoxin (tetanospasmin) and the other a hemolysin (tetanolysin).

Vib·ri·o chol·'er·ae

a bacterial species that produces a soluble exotoxin and is the cause of cholera in humans; it is the type species of the genus Vibrio.

cholera toxin

Infectious disease A heat-sensitive multimeric enterotoxin produced by Vibrio cholera, which transfers ADP-ribose to a G protein, locking adenyl cyclase in an 'on' position by ADP ribosylation of a Gs protein
References in periodicals archive ?
1980) Amino acid sequence homology between cholera toxin and Escherichia coli heat-labile toxin.
Heteropentameric cholera toxin B subunit chimeric molecules genetically fused to a vaccine antigen induces systemic and mucosal immune responses: a potential new strategy to target recombinant vaccine antigens to mucosal immune systems.
They also found that HA-containing HA/SIV VLPs showed higher immune responses than SIV VLPs and both humoral and cellular immune responses observed in HA/SIV VLP immunized groups were equal to or greater than in those groups immunized with the mucosal adjuvant cholera toxin.
The UC San Diego researchers found that cholera toxin acts by two entirely distinct, but cooperating mechanisms to produce diarrhea.
Their classical biotype characteristic was due to the presence of the classical CTX prophage and the deduced amino acids of the nucleotide sequence coding for cholera toxin B subunit belonged to classical biotype.
To fashion the new vaccine, immunologist Hiroshi Kiyono of the University of Tokyo and his colleagues engineered rice plants to make grains that contain a harmless fragment of the cholera toxin.
The vaccine consists of a cocaine derivative and a deactivated cholera toxin which bind on to the drug, making it too big to get into the brain.
A cholera toxin (CTX)-sensitive G-protein ([sim]49 kD) was detected in ganglia, but not in Y-organs.
The motility of sea urchin sperm can be inhibited by bacterial toxins such as cholera toxin and pertussis toxin, which initiate their physiological effects by modulating specific subsets of GTP-binding regulatory proteins (G-proteins) (see reference 9 for a review).
In parallel, development of assays for two different tuberculosis biomarkers and the Cholera toxin is currently in progress.
Changing genotypes of cholera toxin (CT) of Vibrio cholerae O139 in Bangladesh and description of three new CT genotypes.