Description_x000D_ Application_x000D_ Cholera Toxin from Vibrio cholerae has been used as a positive control in cAMP (cyclic AMP) assay for enterotoxins. It has been added as a supplement in cell culture media of primary tumors and epithelial cells._x000D_ Biochem/physiol Actions_x000D_ Toxin consisting of an A subunit (27 kDa) surrounded by five B subunits (approximately 12 kDa each), which attach the toxin to ganglioside GM1 on the cell surface. The A subunit catalyzes ADP-ribosylation of the α-subunit of the stimulatory G protein (Gαs), reducing GTPase activity and activating the α-subunit. This activation of Gαs leads to an increase in the activity of adenylyl cyclase, resulting in increased levels of cAMP. Also ADP-ribosylates transducin in the eye rod outer segments, inactivating its GTPase activity. Cholera toxin has also been reported to ADP-ribosylate tubulin. Shown to be a potent mucosal vaccine adjuvant, inducing T helper cell type 2 responses by inhibiting the production of interleukin-12._x000D_ Features and Benefits_x000D_ This compound is a featured product for Cyclic Nucleotide research. Click here to discover more featured Cyclic Nucleotide products. Learn more about bioactive small molecules for other areas of research at sigma.com/discover-bsm._x000D_ Packaging_x000D_ Package size based on protein content._x000D_ Physical form_x000D_ Lyophilized powder containing Tris buffer salts, sodium chloride, sodium azide and sodium EDTA_x000D_ Reconstitution_x000D_ When reconstituted at 1 mg/mL in water, solution will contain 0.05 M Tris buffer salts, pH 7.5, 0.2 M NaCl, 0.003 M NaN3, and 0.001 M sodium EDTA. Store reconstituted solutions in the refrigerator.