How are gangliosides synthesized?
With the exception of GM4, which is derived from galactosylceramide (GalCer), most gangliosides are synthesized from lactosylceramide (LacCer). First, a simple ganglioside, GM3, is synthesized by addition of a sialic acid to LacCer by CMP-sialic acid: LacCer α2–3 sialyltransferase (ST-I or GM3 synthase).
Is GM1 a ganglioside?
Neurotrophic and Neuroprotective Properties of GM1 GM1 is one of the main gangliosides used for biological experiments: it has been administered to a variety of cells in culture.
What is the function of GM1?
GM1 has important physiological properties and impacts neuronal plasticity and repair mechanisms, and the release of neurotrophins in the brain. Besides its function in the physiology of the brain, GM1 acts as the site of binding for both cholera toxin and E. coli heat-labile enterotoxin (Traveller’s diarrhea).
What are the functions of ganglioside?
Gangliosides are enriched in cell membrane microdomains (“lipid rafts”) and play important roles in the modulation of membrane proteins and ion channels, in cell signaling and in the communication among cells.
Is sphingomyelin a ganglioside?
1) and is at the hub of sphingolipid metabolism (Fig. 2). The attachment of phosphocholine or saccharides to the hydroxyl group of ceramide in the Golgi apparatus leads to the production of sphingomyelin (SM) and glycosphingolipids (GSLs), respectively. Gangliosides are GSLs that contain sialic acid [1], [2].
What is the structure of a ganglioside?
A ganglioside is a molecule composed of a glycosphingolipid (ceramide and oligosaccharide) with one or more sialic acids (e.g. n-acetylneuraminic acid, NANA) linked on the sugar chain.
Why is GM1 a receptor?
The ganglioside GM1 has long been considered the main functional receptor for CT. This idea is supported by the fact that GM1 binds with high affinity to both CTB and the closely related heat-labile toxin B-subunit from E. coli (LTB) [7].
What is GMI disorder?
GM1 gangliosidosis is an inherited disorder that progressively destroys nerve cells (neurons) in the brain and spinal cord. Some researchers classify this condition into three major types based on the age at which signs and symptoms first appear.
Where is GM2 ganglioside found?
Ganglioside GM2 is abundant in cells of the central nervous system and accumulates within the lysosomes of neurons and macrophages.
What is ganglioside receptor?
Gangliosides, glycosphingolipids present in the membranes of neuronal and other cells, are natural receptors for a number of bacterial toxins and viruses whose sensitive detection is of interest in clinical medicine as well as in biological warfare or terrorism incidents.
Is ganglioside a type of sphingolipid?
Glycolipids, a large group of sphingolipids, are so called because they contain one or more molecules of sugar (glucose or galactose). Glycolipids, a general property of which is immunological activity, include the cerebrosides, gangliosides, and ceramide oligosaccharides.
What happens when ganglioside synthesis is interrupted?
Interruption of ganglioside synthesis produces central nervous system degeneration and altered axon-glial interactions. Proc. Natl. Acad. Sci. USA. 2005;102:2725–2730.
How does PMGs act on complex gangliosides?
PMGS acts on major axonal gangliosides such as GD1a and GT1b to produce GM1 (see structures, Figure 3 ). Since the innermost sialic acid on complex gangliosides is sialidase resistant, GM1 accumulates and is not further degraded by PMGS.
How do you make a deacylated ganglioside with two amino groups?
The intermediate deacylated ganglioside GM1 (monodeacetyllyso-GM1) containing two amino groups is obtained by vigorous alkaline hydrolysis of ganglioside GM1 with potassium hydroxide in methanol at 100°.
How is a simple ganglioside (GM3) synthesized?
First, a simple ganglioside, GM3, is synthesized by addition of a sialic acid to LacCer by CMP-sialic acid: LacCer α2–3 sialyltransferase (ST-I or GM3 synthase).