E.coli toxin

ADP-ribosylation by Cholera toxin E. coli toxin Pertussis toxin G a Gjffl Diarrhea of cholera Traveler s diarrhea Pertussis (whooping cough)... 

University of Milan, Italy E. coli toxin B subunit tuberculosis antigen 207-209... 

Shiga toxins and related toxins from E. coli No proteins ( ) 28S rRNA A/-glycosidase Cleavage of 28S rRNA Inhibition of protein synthesis... 

Shiga toxin is produced (i) by Shigella cfysenterica, the cause of bacillary dysentery, (ii) by certain E. coli strains (EHEC, enterohaemorrhagic E. coli cause of the... 

In the gut, many pathogens adhere to the gut wall and produce their toxic effect via toxins which pervade the surrounding gut wall or enter the systemic circulation. Vibrio cholerae and some enteropathic E. coli strains localize on the gut wall and produce toxins which increase vascular permeability. The end result is a hypersecretion of isotonic fluids into the gut lumen, acute diarrhoea and consequent dehydration which may be fatal in juveniles and the elderly. In all these instances, binding to epithelial cells is not essential but increases permeation ofthe toxin and prolongs the presence of the pathogen. 

Tissue culture of susceptible mammalian cells may be used to characterize some bacteria by the toxins they produce. For example, Shiga-like toxins (verotoxins) are produced by E. coli 0157 H7.4,8... 

Different EHEC serotypes are often found in ruminant populations, but most of the research to elucidate the effect of feed type on EHEC prevalence has been based on serotype 0157 H7. The preference for this pathogenic strain is due to its public health importance, its unique phenotypic characteristics that allow a relatively easy identification compared to other serotypes and the fact that ruminants are its most important natural reservoir. Shiga toxin-producing E. coli (STEC) are a larger group that includes EHEC and have also been found in ruminant populations in relatively large prevalence. Because the pathogenicity of most STEC has not been proven, we will focus our discussion on serotype 0157 H7. 

However, in case of acute clinical mastitis, it is widely accepted that animal welfare considerations should take prevalence. If both farmer and veterinarian are not familiar with non-antibiotic treatments, they should be advised to use broad-spectrum antibiotics immediately, because any delay (e.g. the 2-3 days it often takes between diagnosis and the return of microbiological test results) may seriously harm the animal. This approach should, however, only be taken after a sound clinical diagnosis, since antibiotic treatments themselves may lead to dramatic aggravation of the condition. For example, E. coli inflammations are able to develop into severe toxaemia, because increased levels of toxins are released into the animal tissues when E. coli cells are killed or stressed by antibiotic treatments. Also, if yeasts are the main cause or form part of the pathogen complex that causes mastitis, their growth and proliferation may be supported by the administration of anti-bacterial antibiotics (Crawshaw et al., 2005). 

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... 

Further studies concerning the activity of glycodendrons containing two or four peripheral GMjOS against the E. coli heat-labile toxin (LTBh) B-pentamer have been similarly described (Fig. 43).313... 

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. 

E. coli 0157 H7 (EHEC if blood in stool also test for Shiga toxin and refer isolates if toxin pos.)... 

Savarino SJ, Fasano A, Watson J, Martin BM, Levine MM, Guandalini S, Guerry P Enteroaggregative Escherichia coli heat-stable enterotoxin 1 represents another subfamily of E. coli heat-stable toxin. Proc Natl Acad Sci USA 1993 90 3093-3097. 

Baldwin TJ, Knutton S, Sellers L, Hernandez HA, Aitken A, Williams PH Enteroaggregative Escherichia coli strains secrete a heat-labile toxin antigenically related to E. coli hemolysin. Infect Immun 1992,60 2092-2095. 

Enterotoxigenic E. coli B subunits of the heat labile toxin (LTB) Maize seed Elicited neutralizing antibodies. Immunogenic when administered orally. Serum and secretory immune responses in humans. Partially protective in mouse gut fluid assay. 27-29, 89, unpublished data... 

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