Interaction of cholera toxin and membrane GM1 ganglioside of small intestine.

摘要: Ganglioside GM1 was isolated from the small intestinal mucosa of man, pig, and beef amounted to 0.1, 2.0, 43 nmol per g fresh weight, respectively. These differences in content were associated with a quantitatively differing ability mucosal cells bind cholera toxin. Human bound about 15,000 toxin molecules when saturated toxin, porcine 120,000, bovine 2,600,000 molecules. The association constant (KA) binding was, for all three species, 10(9) liters/mol. Exogenously added ganglioside incorporated as well intact rabbit bowel. increment correspondingly increased number sites whereas KA unchanged. incorporation sensitivity bowel diarrheogenic action Vibrio cholerae sialidase hydrolyzed diand trisialogangliosides GM1. However, enzyme did not change pattern mucosa, had very little influence on cells, alter results demonstrate relationship between concentration, biologic Thus, study strongly supports concept that is receptor