The cholera toxin B pentamer (CtxB(5)), which belongs to the AB(5) toxin family, is used as a model study for protein assembly. The effect of the pH on the reassembly of the toxin was investigated using immunochemical, electrophoretic and spectroscopic methods. Three pH-dependent steps were identified during the toxin reassembly: (i) acquisition of a fully assembly-competent fold by the CtxB mo...

Although cholera toxin (Ctx) and Escherichia coli heat-labile enterotoxin (Etx) are known to be potent mucosal adjuvants, it remains controversial whether the adjuvanticity of the holotoxins extends to their nontoxic, receptor-binding B subunits. Here, we have systematically evaluated the comparative adjuvant properties of highly purified recombinant EtxB and CtxB. EtxB was found to be a more p...

Salmonella typhimurium aroA strains (SL3261), expressing high levels of the Gag protein of feline immunodeficiency virus (FIV) fused with maltose binding protein (SL3261-MFG), were constructed using an invertible promoter system that allows the stable expression of heterologous antigens at levels toxic for bacteria. A SL3261 strain expressing the B subunit of cholera toxin by a similar system (...

The present study aimed to construct and evaluate the live attenuated Vibrio cholerae serogroup O139 vaccine candidate, in which genes encoding protective antigens were integrated into the chromosomal DNA. Using the initial strain, O139-ZJ9693, the toxin-linked cryptic (TLC) and cholera toxin (CTX) genetic elements and repeats in the toxin (RTX) gene cluster were deleted from its chromosomal DN...

BACKGROUND Cholera toxin B subunit (CTB) has been extensively considered as an immunogenic and adjuvant protein, but its yield of expression is not satisfactory in many studies. The aim of this study was to compare the expression of native and mutant recombinant CTB (rCTB) in pQE vector. METHODS ctxB fragment from Vibrio cholerae O1 ATCC14035 containing the substitution of mutant ctxB for ami...

TrkB is a high affinity receptor for the brain derived neurotrophic factor (BDNF) and its phosphorylation stimulates activation of several intracellular signalling pathways linked to cellular growth, differentiation and maintenance. Identification of various activators and inhibitors of the TrkB receptor and greater understanding their binding mechanisms is critical to elucidate the biochemical...

cholera toxin b subunit (ctxb) is a homopantameric, nontoxic subunit of cholera toxin that is responsible for its binding to the cell and has been known as a mucosal adjuvant for vaccines that could increase homoral and mocusal immunity response. in this work, the ctxb gene was fused to the stxb gene from shigella dysenteriae type i a vaccine antigen candidate against this pathogen, by a nonfur...

BACKGROUND AND OBJECTIVES The antimicrobial susceptibility patterns and genetic characteristics of Vibrio cholerae O1, which is responsible for several cholera epidemics in Nigeria, are not reported in detail since 2007. In this study, we screened V. cholerae O1 El Tor biotype isolates from cholera cases and water samples from different states to investigate their phenotypic and genetic attribu...

objectives: ctxb (cholera toxin b subunit) contributes to a vaccine's efficacy by stimulating production of the anti-ctxb antibody. various attempts have been made to increase production of this antibody. chitosan is a mucoadhesive polysaccharide that has tremendous potential for oral vaccine delivery in terms of its exclusive features that include biocompatibility, biodegradability, high charg...