Enterotoxin

Diarrhea is a common problem that is usually self-limiting and of short duration. Increased accumulations of small intestinal and colonic contents are known to be responsible for producing diarrhea. The former may be caused by increased intestinal secretion which may be enterotoxin-induced, eg, cholera and E. col] or hormone and dmg-induced, eg, caffeine, prostaglandins, and laxatives decreased intestinal absorption because of decreased mucosal surface area, mucosal disease, eg, tropical spme, or osmotic deficiency, eg, disaccharidase or lactase deficiency and rapid transit of contents. An increased accumulation of colonic content may be linked to increased colonic secretion owing to hydroxy fatty acid or bile acids, and exudation, eg, inflammatory bowel disease or amebiasis decreased colonic absorption caused by decreased surface area, mucosal disease, and osmotic factors and rapid transit, eg, irritable bowel syndrome. 

Gram-positive (whole organisms peptidoglycans [e.g., muramyl dipeptide] lipoteichoic acids exotoxins enterotoxins erythrogenic toxins group B polysaccharides)... 

Bacterial toxins Heat-labile enterotoxin of Ecoli and cholera toxin... 

Other disorders in which glycoproteins have been implicated include hepatitis B and C, Creutzfeldt-Jakob disease, and diarrheas due to a number of bacterial enterotoxins. It is hoped that basic smdies of glycoproteins and other glycoconjugates (ie, the field of glycobiology) will lead to effective treatments for diseases in which these molecules are involved. Already, at least two disorders have been found to respond to oral supplements of sugars. 

V. cholerae is a gram-negative bacillus. Vibrios pass through the stomach to colonize the upper small intestine. Vibrios have filamentous protein extensions that attach to receptors on the intestinal mucosa, and their motility assists with penetration of the mucus layer.2 The cholera enterotoxin consists of two subunits, one of which (subunit A) is transported into the cells and causes an increase in cyclic AMP, which leads to a deluge of fluid into the small intestine.20 This large volume of fluid results in the watery diarrhea that is characteristic of cholera. The stools are an electrolyte-rich isotonic fluid, the loss of which results in blood volume depletion followed by low blood pressure and shock.2 Of note, the diarrheal fluid is highly infectious. 

Schutyser E, Struyf S, Wuyts A, et al. Selective induction of CCL18/PARC by staphylococcal enterotoxins in mononuclear cells and enhanced levels in septic and rheumatoid arthritis. Eur J Immunol 2001 31(12) 3755—3762. 

To ensure the safety of food products, representative samples must be inspected so that foodborne bacteria can be identified.15,18,19 Bacteria producing heat-stable enterotoxins, such as Staphylococcus aureus, may be identified by biochemical and serological techniques.20,21 Molecular methods are now widely used for the identification of many pathogenic foodborne bacteria,15,22,23 In addition bacteria used as starter cultures for cheese, yogurt, other fermented foods and beverages, and probiotic dietary supplements may be identified for quality assurance.22,24,25... 

Toxins (typically high molecular weight proteins), such as botulinum toxin, ricin, or Staphyloccocal enterotoxin (SEB) or T-2 toxin (which actually is a small molecule). 

Okada K, Sakusabe N, Kobayashi A, Hoshi N, Sato K. Prevention of lung metastasis by intra-tumoural injection of Cepharanthin and staphylococcal enterotoxin B in transplantable rat osteosarcoma. Jpn J Cancer Res 1999 90 928-933. 

McEwan, G. and M. Lucas. The effect of E. coli STa enterotoxin on the absorption of weakly dissociable drugs from rat proximal jejunum in vivo, Br.J. Pharmacol. 1990, 101, 937-943... 

Representatives of medium-size analytes detected by affinity biosensors based on spectroscopy of guided modes include food-safety related analytes such as staphylococcal enterotoxin B , botulinum toxin, and E. coli... 

Rasooly A., Surface plasmon resonance analysis of staphylococcal enterotoxin B in food, Journal of Food Protection 2001 64 37-43. 

Homola J., Dostalek J., Chen S., Rasooly A., Jiang S., Yee S.S., Spectral surface plasmon resonance biosensor for detection of staphylococcal enterotoxin B (SEB) in milk, Intern. J. Food Microbiology 2002 75 61-69. 

Spangler B.D., Wilkinson E.A., Murphyb J.T., Tyler B.J., Comparison of the Spreeta surface plasmon resonance sensor and a quartz crystal microbalance for detection of Escherichia coli heat-labile enterotoxins, Analytica Chimica Acta 2001 444 149-161. 

Tempelman L.A., King K.D., Anderson G.P., Ligler F.S., Quantitating staphylococcal enterotoxin B in diverse media using a portable fiber optic biosensor, Anal. Biochem. 1996 223 50-57. 

Shriver-Lake L.C, Shubin Y., Ligler F.S., Detection of staphylococcal enterotoxin B in spiked food samples, J. Food Protect. 2003 66 1851-1856. 

FIG. 30. The best ligands against E. coli heat-labile enterotoxin. 

J. C. Pickens, E. A. Merritt, M. Ahn, C. L. M. J. Verlinde, W. G. J. Hoi, and E. Fan, Anchor-based design of improved cholera toxin and E. coli heat-labile enterotoxin receptor binding antagonists that display multiple binding modes, Chem. Biol., 9 (2002) 215-224. 

J. P. Thompson and C.-L. Schengrund, Oligosaccharide-derivatized dendrimers Defined multivalent inhibitors of the adherence of the cholera toxin B subunit and the heat labile enterotoxin of E. coli to GM1, Glycoconjug. J., 14 (1997) 837-845. 

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