Brefeldin A and Exo1 Completely Releave the Block of Cholera Toxin Action by a Dipeptide Metalloendoprotease Substrate
نویسنده
چکیده
Cholera toxin (CT), the enterotoxin secreted by Vibrio cholerae classical as well as El Tor biotypes, is the major causative agent of the acute diarrheal disease of humans. CT and the Escherichia coli heat labile enterotoxin (LT),are structurally and immunologically highly homologous,seeing that they belong to the same enterotoxin family (de Haan and Hirst, 2004; Spangler, 1992; Vanden Broeck et al., 2007). Both are oligomeric proteins of the A-B type. CT is composed of one A or activating subunit (CT-A Mr 27,400), which consists of two distinct polypeptide chains CT-A1 (Mr 22,000) and CT-A2 (Mr 5,400), linked by a single disulfide bridge, and 5 identical B subunits (Mr 11,600) arranged in a ring like configuration (CT-B).
منابع مشابه
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Simian Virus 40 (SV40) is a non-enveloped virus which has been shown to pass from surface caveolae to the endoplasmic reticulum (ER) in an apparently novel infectious entry pathway. We now show that the initial entry step is blocked by brefeldin A (BFA) and by incubation at 20°C. Subsequent to the entry step, the virus reaches a domain of the rough ER by an unknown pathway. This intracellular t...
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