Escherichia coli heat-stable enterotoxin STa
Product Number E 5763
Storage Temperature -0 °C
Product Description This product is subgroup ST1A and a proprietary
Molecular Weight: 1,972 Da strain of E. coli used to produce this product was
8
Synonyms: STI, ST1, Stmouse isolated from a human source.
Escherichia coli is a common intestinal pathogen Precautions and Disclaimer
responsible for endemic diarrhea. Although E. coli is For Laboratory Use Only. Not for drug, household or
not a common cause of diarrhea in developed other uses.
countries, occasional outbreaks have occurred in
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Europe and the United States. Preparation Instructions
This product is soluble in acidified water (pH 2-3) or
E. coli is a normal part of intestinal flora. Benign acidic aqueous buffers (1 µg/10 µl). For dilute
strains of E. coli colonize the large intestine and a solutions it is recommended that 0.1 to 1% BSA be
lower portion of the small intestine. Pathogenic strains added to prevent container adsorption.
of E. coli invade areas of the small intestine that are
normally unsuitable for E. coli attachment and produce Storage/Stability
toxins resulting in symptoms similar to those of cholera Alkaline solutions are unstable. Acidic solutions can
such as severe diarrhea. Entertoxigenic E. coli be stored frozen as single-use aliquots
(ETEC) pathogenicity is due in part to the ability to
invade the upper portion of the small intestine and the References
ability to produce toxins. Both the ability to colonize 1. Blanco, J., et al., Serotypes and colonization
the epithelial surface of the upper small intestine factors of enterotoxigenic Escherichia coli isolated
(pili or fibrils) and toxin production are plasmid- in various countries. Eur. J. Epidemiol., 9(5),
1,2,3
encoded. 489-496 (1993).
2. Blanco, M., et al., Genes coding for enterotoxins
ETEC strains produce heat-labile enterotoxins (LT) and verotoxins in porcine Escherichia coli strains
and/or heat-stable enterotoxins (STs). STs are belonging to different O:K:H serotypes:
classified as STa (also called STI, ST1, or ST mouse) relationship with toxic phenotypes. J. Clin.
1,2,3
and STb (also called STII, ST2, or STpig). The Microbiol., 35(11), 2958-2963 (1997).
heat-labile toxins (LT) are inactivated after 30 minutes 3. The Biology of Plasmids, Summers, D. K.,
at 60 °C. The heat-stable toxins (STs) are not Blackwell Science (Cambridge, MA: 1996),
inactivated after 30 minutes at 100 °C. Testing
3
pp.3-6, 79-81.
isolates for toxin production with bioassays or 4. Dreyfus, L. A., et al., Chemical properties of heat-
2,4,5,6
immunoassays can identify ETEC strains. stable enterotoxins produced by enterotoxigenic
Escherichia coli of different host origins. Infect.
It is believed that STa may mimic naturally occurring Immun., 42(2), 539-548 (1983).
peptide hormones and bind to intestinal receptors 5. Alderete, J. F., and Robertson, D. C., Purification
involved in the body's regulation of fluid levels and chemical characterization of the heat-stable
resulting in the stimulation of intestinal fluid secretion enterotoxin produced by porcine strains of
7
and severe diarrhea. enterotoxigenic Escherichia coli. Infect. Immun.,
19(3), 1021-1030 (1978).
6. Aimoto, S., et al., Amino-acid sequence of a heat-
stable enterotoxin produced by human
enterotoxigenic Escherichia coli. Eur. J. Biochem.,
129(2), 2572-63 (1982).
7. Greenberg, R. N., et al., Comparison of effects of 8. Thompson, M. R., and Giannella, R. A., Revised
uroguanylin, guanylin, and Escherichia coli heat- amino acid sequence for a heat-stable enterotoxin
stable enterotoxin STa in mouse intestine and produced by an Escherichia coli strain (18D) that
kidney: evidence that uroguanylin is an intestinal is pathogenic for humans. Infect. Immun., 47(3),
natriuretic hormone. J. Investig. Med., 45(5), 834-836 (1985).
276-282 (1997).
CMK/RXR 10/03
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