cholera toxin b subunit (ctb) has been extensively studied as an immunogen, adjuvant, and inducer of oral tolerance in many investigations. production of ctb has been carried out in the bacterial, plant, insect and yeast expression systems. in this study the expression of the ctb containing a 6xhis-tagged was performed by escherichia coli (e.coli) m15. the yield of purified pentameric recombina...

Pancreatic carcinoma is one of the most aggressive tumor entities, and standard chemotherapy provides only modest benefit. Therefore, specific targeting of pancreatic cancer for early diagnosis and therapeutic intervention is of great interest. We have previously shown that the cellular receptor for Shiga toxin B (STxB), the glycosphingolipid globotriaosylceramide (Gb(3) or CD77) is strongly in...

Pancreatic carcinoma is one of themost aggressive tumor entities, and standard chemotherapyprovides only modest benefit. Therefore, specific targeting of pancreatic cancer for early diagnosis and therapeutic intervention is of great interest. We have previously shown that the cellular receptor for Shiga toxin B (STxB), the glycosphingolipid globotriaosylceramide (Gb3 or CD77) is strongly increa...

bacterial protein toxins have been exploited as therapeutic agents and as vaccines. an issue of deserving interest is development of new generations of vaccines and immune adjuvants. in this study an active assembled recombinant shiga toxin of escherichia coli (rstx1) and its derivatives, recombinant a and b subunits (stx1-a and stx1-b), were used to immunize mice. the elicited antibody respons...

Bacterially derived exotoxins kill eukaryotic cells by inactivating factors and/or pathways that are universally conserved among eukaryotic organisms. The genes that encode these exotoxins are commonly found in bacterial viruses (bacteriophages). In the context of mammals, these toxins cause diseases ranging from cholera to diphtheria to enterohemorrhagic diarrhea. Phage-carried exotoxin genes ...

Shiga and the Shiga-like toxins are related protein toxins produced by Shigella dysenteriae and certain strains of Escherichia coli. These toxins are composed of two non-covalently attached, modular parts: the A moiety (StxA) containing the enzymatically active A1 fragment, and the non-toxic, pentameric binding moiety (StxB). Stx binds specifically to the glycosphingolipid globotriaosylceramide...

BACKGROUND Shigella enterotoxin 1 is a novel enterotoxin elaborated by Shigella flexneri 2a that causes fluid accumulation in rabbit ileal loops and a rise in short circuit current in Ussing chambers. AIMS To gain insights into the mechanism of action of shigella enterotoxin 1. METHODS Supernatants from genetically engineered clones either overexpressing shigella enterotoxin 1 or producing ...

Peptide-protein conjugates are useful tools in different fields of research as, for instance, the development of vaccines and drugs or for studying biological mechanisms, to cite only few applications. N-Succinimidyl carbamate (NSC) chemistry has been scarcely used in this area. We show that unprotected peptides, featuring one lysine residue within their sequences, can be converted in good yiel...

Shiga toxin (Stx) causes diarrhea-associated hemolytic uremic syndrome by damaging renal microvascular endothelium. The pentameric B subunits of Stx types 1 and 2 (Stx1B and Stx2B) are sufficient to stimulate acute VWF secretion from endothelial cells, but Stx1B and Stx2B exert distinct effects on Ca(2+) and cAMP pathways. Therefore, we investigated other signaling components in StxB-induced VW...