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.

Studies on the Vibrio cholerae mucinase complex. I. Enzymic activities associated with the complex325

“…The precise role of the neuraminidase is still unsolved. Gascoyne and van Heyningen (1979) and Ackerman et al (1980) Further studies are being pursued in this laboramental and commercial preparations of V . cholerae tory to characterise the individual enzyme componeuraminidase are contaminated with other nents of the mucinase complex and their role in V .…”

Enterotoxins from gram-negative bacteria relevant for veterinary medicine

“…Unmasking of the GMI receptor sites by choleratoxin has been found in intestinal mucosa homogenates by Gascyone and Van Heyningen (1979). In general the stronger diarrhoeic effect of choleratoxin might be due to the receptor unmasking effect by the sialidase of V. cholerae.…”