exotoxin


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exotoxin

 [ek´so-tok″sin]
a potent toxin formed and excreted by the bacterial cell and found free in the surrounding medium; exotoxins are the most poisonous substances known. They are protein in nature and heat labile, and are detoxified with retention of antigenicity by treatment with formaldehyde. Bacteria of the genus Clostridium are the most frequent producers of exotoxins; diphtheria, botulism, and tetanus are all caused by such toxins. adj., adj ex´otoxic.

ex·o·tox·in

(ek'sō-tok'sin),
A specific, soluble, antigenic, usually heat labile, injurious substance elaborated by certain gram-positive or gram-negative bacteria; it is formed within the cell, but is released into the environment where it is rapidly active in extremely small amounts; most exotoxins are proteinaceous (MW 70,000-900,000) and can have the toxic portion of the molecule destroyed by heat, prolonged storage, or chemicals; the nontoxic but antigenic form is a toxoid.

exotoxin

(ĕk′sō-tŏk′sĭn)
n.
A poisonous substance secreted by a microorganism and released into the medium in which it grows.

ex·o·tox·in

(eks'ō-tok'sin)
A specific, soluble, antigenic, usually heat labile, injurious substance elaborated by some bacterial species; it is formed within the cell but is released into the environment where it is rapidly active in extremely small amounts; most exotoxins are proteinaceous in nature.
Synonym(s): extracellular toxin.

exotoxin

A powerful protein poison, formed by some bacteria, which is released and which may cause severe damage either locally or, if carried away by the blood, at a remote distance. Diphtheria exotoxin destroys throat lining tissue, where the organism settles, but can also travel to damage the heart and the kidneys.

exotoxin

a poison produced by a living CELL and released into the environment. It can affect various ORGANS and systems of the body.

Exotoxin

A poisonous secretion produced by bacilli which is carried in the bloodstream to other parts of the body.
Mentioned in: Diphtheria

ex·o·tox·in

(eks'ō-tok'sin)
A specific, soluble, antigenic, usually heat labile, injurious substance elaborated by certain gram-positive or gram-negative bacteria.
References in periodicals archive ?
isolates (%) Alginate algD 60 (98) Elastase B lasB 60 (98) Exotoxin A toxA 49 (80) Exoenzyme S exoS 20 (33) Exoenzyme U exoU 20 (33) Pyocyanin 53 (87)
Pastan, "A guide to taming a toxin-recombinant immunotoxins constructed from Pseudomonas exotoxin A for the treatment of cancer," The FEBS Journal, vol.
Scarlet fever is caused by a limited number of Streptococcus pyogenes lineages and is associated with the exotoxin genes ssa, speA and speC.
Archer et al., "Progress report of a Phase I study of the intracerebral microinfusion of a recombinant chimeric protein composed of transforming growth factor (TGF)-[alpha] and amutated form of the Pseudomonas exotoxin termed PE-38 (TP-38) for the treatment of malignant brain tumors," Journal of Neuro-Oncology, vol.
(2004) Proapoptotic effect of proteolytic activation of matrix metalloproteinases by Streptococcus pyogenes thiol proteinase (Streptococcus pyrogenic exotoxin B).
Protection against Exotoxin A (ETA) and Pseudomonas aeruginosa Infection in Mice with ETA-Specific Antipeptide Antibodies.
Exotoxin production medium [32] Enriched egg yolk medium [13] Sugar fermentation medium [13] Aesculin hydrolysis medium [11] Gelatin medium [35] Indole medium[11].
Several Phase I and II studies with other targeted cytotoxins followed in succeeding years, including IL-4, IL-13, transforming growth factor (TGF)-a conjugated to pseudomonas exotoxin, herpes simplex virus (HSV)-1-tk gene-containing liposomes, and 131I-labeled chimeric monoclonal antibody to histone H1 (Cotara) [10-14].
SEB is another exotoxin produced by Staphylococcus aureus, and is also responsible for staphylococcal food poisoning in humans.
pyogenes grown in the presence of rhodomyrtone produced reduced amounts of known virulence factors, such as the glyceraldehyde-3-phosphate dehydrogenase, the CAMP factor, and the streptococcal pyrogenic exotoxin C.
A team from A*STAR's Institute of Molecular and Cell Biology has discovered the secret recipe for 'antidotes' that could neutralize the deadly plant toxin Ricin - widely feared for its bioterrorism potential - as well as the Pseudomonas exotoxin responsible for the tens of thousands of hospital-acquired infections in immune-compromised patients around the world.