Cholera Toxin B subunit
SIGMA/SAE0069 - recombinant, expressed in HEK 293 cells, subunit A free
Synonym: CTB; CTxB; Cholera enterotoxin B chain; Cholera enterotoxin gamma chain; Cholera enterotoxin subunit B; Choleragenoid; ToxB
Product Type: Chemical
The activity of Cholera Toxin B subunit (CTxB) recombinant (Cat. No. SAE0069) was measured in a binding assay. The EC50 is defined as the CTxB concentration with binding saturation of 50% to GM1, in an ELISA-based assay.
PC12 cells were incubated with either Cholera Toxin B subunit (CTxB) recombinant (Cat. No. SAE0069) (A) or with no CTxB (B) as a control. Cells were fixed and permeabilized. Fixed cells were stained with rabbit anti-cholera toxin antibody, followed by incubation with Atto 488-conjugated secondary antibody. Cells were counterstained with DAPI (blue) to stain nuclei. The cells were visualized by fluorescent microscopy.
| assay | ≥95% (SDS-PAGE) |
| form | lyophilized powder |
| mol wt | calculated mol wt 13 kDa |
| observed mol wt ~13 & 20 kDa by SDS-PAGE (reducing) | |
| pentamer observed mol wt ~70 kDa by SDS-PAGE (non-reducing) (Under non-reducing conditions, it migrates as pentamer of ~70 kDa, consistent with the pentamerization of CTXB.) | |
| quality | (The protein is recombinant, and therefore has no contamination of the highly toxic Cholera toxin A subunit.) |
| Quality Level | 200  |
| recombinant | expressed in HEK 293 cells |
| solubility | H2O: soluble 11 mg/mL |
| specific activity | (Binds to GM1 ganglioside. The binding EC50 is lower than 1 ug/ml) |
| storage temp. | −20°C |
| UniProt accession no. | P01556  |
| Analysis Note: | Activity measured by ELISA using ganglioside GM1-coated multiwell plates, rabbit anti-Cholera toxin B subunit antibodies, and peroxidase-labeled goat anti-rabbit IgG as the secondary antibody. 50% saturation of binding was achieved with ≤1 μg of Cholera toxin B subunit per mL. |
| Application: | Cholera Toxin B subunit has been used: • for macrophage stimulation and i.p. injection in a study to determine the endotoxin sensitivity of Caspase-4. • in transganglionic and retrograde tract-tracing method combined with dual-immunofluorescence histochemistry of adult rat Vmes neuron cells. |
| General description: | The advantage of this product over the native CTXB is that it has no traces of Vibrio cholera, and no contamination of the highly toxic Cholera toxin A subunit. This product is expressed in human HEK 293 cells as a C-terminally his-tagged protein with a calculated molecular mass of 13 kDa (amino acids Thr22-Asn124). |
| Physical form: | Lyophilized from 0.22 μm filtered solution in PBS, pH7.4. |
| Reconstitution: | When reconstituted with water to a final concentration of 1 mg of CTB per ml, the solution will contain 1X PBS |
| RIDADR | NONH for all modes of transport |
| WGK Germany | WGK 2 |
| Flash Point(F) | Not applicable |
| Flash Point(C) | Not applicable |
| Purity | ≥95% (SDS-PAGE) |
| activity | specific activity: (Binds to GM1 ganglioside. The binding EC50 is lower than 1 ug/ml) |
| Storage Temp. | −20°C |
| UNSPSC | 12352200 |