globosydy

Globosydy, known in English as globosides, are a class of neutral glycosphingolipids found in cell membranes. They consist of a ceramide backbone linked to an oligosaccharide chain that typically contains multiple sugar residues and lacks sialic acid. They are distinct from gangliosides, which carry sialic acid, and cerebrosides, which have a single sugar.

They are widely distributed in animal tissues, enriched in certain membranes; they participate in membrane organization, cell–cell recognition, and can serve as receptors for pathogens or toxins. Some globosides function as components of blood group antigen systems.

Biosynthesis occurs in the Golgi apparatus via glycosyltransferases that extend a ceramide with sugar units; catabolism occurs in lysosomes by specific glycosidases. Abnormal accumulation of a globoside, notably globotriaosylceramide (Gb3), underlies Fabry disease when the enzyme alpha-galactosidase A is deficient. Treatment includes enzyme replacement therapy.

A well-known example is Gb3, which serves as the receptor for Shiga toxins produced by Shigella dysenteriae and some Escherichia coli, linking globosides to severe disease outcomes such as hemolytic-uremic syndrome. The field investigates globosides for their roles in development, immunity, and disease.