Cholera toxin subunit B (CTB) is the nontoxic portion of cholera toxin. Its affinity to the monosialotetrahexosylganglioside (GM1) that is broadly distributed in a variety of cell types including epithelial cells of the gut and antigen presenting cells, macrophages, dendritic cells, and B cells, allows its optimal access to the immune system. CTB can easily be expressed on its own in a variety ...

There is increasing interest to use oral cholera vaccination as an additional strategy to water and sanitation interventions against endemic and epidemic cholera. There are two internationally-available and WHO-prequalified oral cholera vaccines: an inactivated vaccine containing killed whole-cells of V. cholerae O1 with recombinant cholera toxin B-subunit (WC/rBS) and a bivalent inactivated va...

We used cholera toxin, which binds exclusively and with a high affinity to the ganglioside GM1, as a probe to investigate the distribution of this glycolipid on the surface of mouse lymphocytes. When lymphocytes are incubated with cholera toxin (or its B subunit) and then sequentially with horse anti-toxin and FITC-swine anti-horse Ig at 37°C, the cholera toxin-ganglioside GM1 complex is redist...

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...

The present study uses the B subunit of cholera toxin, a protein that binds specifically to ganglioside GM1, to examine the role of endogenous GM1 in the process of growth and differentiation of mouse neuroblastoma N18 cells. Binding of the B subunit to neuroblastoma N18 cells inhibited DNA synthesis with concomitant induction of differentiation. The B subunit induced pronounced morphological c...

A mixed phospholipid-cholestrol bilayer, with cholera toxin B (CTB) units attached to the monosialotetrahexosylganglioside (GM1) binding sites in the distal leaflet, was deposited on a Au(111) electrode surface. Polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) measurements were used to characterize structural and orientational changes in this model biological membr...

The current model for autodisplay suggests a mechanism that allows a passenger protein to be translocated across the outer membrane by coordinate action of a C-terminal beta-barrel and its preceding linking region. The passenger protein, linker, and beta-barrel are together termed the autotransporter, while the linker and beta-barrel are here referred to as the translocation unit (TU). We chara...

Cholera toxin (CT) consists of a pentameric B subunit that binds to specific cell surface receptors identified as ganglioside GM1 and an A subunit that activates adenylylcyclase. The A subunit consists of A1 and A2 peptides linked by a disulfide bond; A2 acts to connect A to B, whereas A1 is an ADP-ribosyltransferase that modifies the alpha subunit of the stimulatory G protein (Gs). How the tox...

Enterotoxigenic Escherichia coli (ETEC) is a significant source of morbidity and mortality worldwide. One major virulence factor released by ETEC is the heat-labile enterotoxin LT, which is structurally and functionally similar to cholera toxin. LT consists of five B subunits carrying a single catalytically active A subunit. LTB binds the monosialoganglioside G(M1), the toxin's host receptor, b...