Unmasking of actual and potential receptor sites for cholera toxin in intestinal mucosal homogenates

Abstract

Endongenous and exogenous sialidases appear to unmask sialidase-stable and sialidase-labile gangliosides in intestinal mucosal homogenates by attacking glycoproteins. Exogenous (but not endogenous) sialidase then converts sialidase-labile gangliosides into the cholera toxin-binding, sialidase-stable ganglioside GM1 (galactosyl-N-acetylgalactosaminyl [sialosyl] lactosyl ceramide). Since Vibrio cholerae produces sialidase, these observations may be relevant to the course of cholera.