STAPHYLOCOCCUS Staphylococcal Toxin

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Staphylococcus aureus is known for its ability to produce a variety of toxins and many disease syndromes. One of the most frequently observed diseases is staphylococcal tonsillitis. These bacteria are frequently present on tonsils of healthy carriers. Patients that are affected by tonsillitis swallow staphylococci hidden in tonsil crypts. However, in this case staphylococci do not cause any gastrointestinal symptoms in the host organism, even if they enter the gastrointestinal tract. The barrier of gastric juice and conditions in a small intestine inhibit the outgrowth of staphylococci and toxin production -gastroenteritis is caused solely by a toxin produced outside the host organism. 

De Boer, M.L., Kum, W.W. and Chow, A.W., Staphylococcus aureus isogenic mutant, deficient in toxic shock syndrome toxin-1 but not staphylococcal enterotoxin A production, exhibits attenuated virulence in a tampon-associated vaginal infection model of toxic shock syndrome, Can. J. Microbiol., 45, 250-256,... 

Monday SR, Bohach GA (1999) Use of multiplex PCR to detect classical and newly described pyrogenic toxin genes in staphylococcal isolates. 1 Qin Microbiol 37 3411-3414 Monecke S, Slickers P, Ehricht R (2008) Assignment of Staphylococcus aureus isolates to clonal complexes based on microarray analysis and pattern recognition. FEMS Immunol Med Microbiol 53 237-251... 

Sato H, Matsumori Y, Tanabe T, Saito H, Shimizu A, Kawano J (1994) A new type of staphylococcal exfoliative toxin from a Staphylococcus aureus strain isolated from a horse with phlegmon. Infect Immun 62 3780-3785... 

Omoe K, Hu DL, Takahashi-Omoe H, Nakane A, Shinagawa K Comprehensive analysis of classical and newly described staphylococcal superantigenic toxin genes in Staphylococcus aureus isolates. FEMS Microbiol Lett 2005 246 191-198. 

Staphylococcus aureus produces a set of proteins [e.g., staphylococcal enterotoxin A (SEA), SEB, toxic shock syndrome toxin 1 (TSST-1)], which act both as superantigens and toxins. Hamad and coworkers (66)found dose-dependent, facilitated transcytosis of SEB and TSST-1, but not SEA, in Caco-2 cells. They extended their studies in mice in vivo by showing that ingested SEB appears in the blood more efficiently than does SEA. 

Staphylococcal enterotoxins (SEs) are the most widely studied of the toxic foodborne proteins. Although these toxins are produced by various strains of Staphylococcus, evidence has shown they are primarily produced by the Staphylococcus aureus strain. Currently there are nine enterotoxins (A, B, C, D, E, G, H, I, J) that have been identified in a wide variety of food products meat, poultry and egg products, milk and dairy products, as well as bakery products [35]. The infective dose of toxins is estimated to be 0.1 p-g/kg body mass [36]. Detection of the presence of SEs is typically done through isolation in the suspected food source [6]. 

Staphylococcal enterotoxin B (SEB) is one of seven enterotoxins produced by strains of Staphylococcus aureus. SEB, the best understood of the staphylococcal enterotoxins, can be regarded as the type enterotoxin. Staphylococcal enterotoxins, toxic shock syndrome toxin-1 (TSST-1), and certain other bacterial products (such as streptococcal pyrogenic exotoxins [SPE]) and viral products (which are not discussed in this chapter) are commonly referred to as superantigens because of their profound effects on the immune system. Minute concentrations of superantigens can activate the immune system receptors because they bind with strong avidity to T-cell antigen receptors and class II molecules of the major histocompatibility complex (MHC). 

The staphylococcal enterotoxins are a family of superantigen protein toxins produced by strains of Staphylococcus aureus. Staphylococcal enterotoxin B (SEB), a toxin often associated with food poisoning, was weaponized as an incapacitating agent by the United States during in the 1960s. When inhaled as a respirable aerosol, SEB causes fever, severe respiratory distress, headache, and sometimes nausea and vomiting. The mechanism of intoxication is... 

Staphylococcal entero-toxin B Enterotoxin produced by Staphylococcus aureus, may be inhaled or ingested. Onset as eariy as 3-4 hours, duration 3-4 days. Fever, chills, myalgia, cough, dyspnea, headache, nausea, vomiting symptoms usual onset 8-12 hours after exposure. Treatment supportive. Victims are not contagious, do not need isolation. Vaccine and immunotherapy effective in animals. 

Staphylococcal enterotoxin B (SEB) is one of several toxins produced by the bacteria Staphylococcus aureus. SEB commonly causes food poisoning in humans. If... 

Most people encounter the bacterium Staphylococcus aureus and its toxin staphylococcal enterotoxin type B (SEB) at some point in their lives fi om food (ptomaine) poisoning. Some of these strains of bacteria have been responsible for toxic shock syndrome among women using feminine hygienic products, especially during the peak of the affliction in the early 1980s. 

Another group of toxins that are so far known not to act beyond plasma membrane are staphylococcal enterotoxins and heat shock syndrome toxins produced by Staphylococcus aureus. These toxins act as superantigens (Marrack and Kapler, 1990), and have binding sites for major histocompatibility complex II on macrophage cell membrane as well as for the T-cell antigen receptor. Upon binding with T-cells, these toxins evoke massive release of cytokines which become harmful in such a large amount. 

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