NGlycolylneuraminsäure

NGlycolylneuraminic acid, often abbreviated Neu5Gc, is a member of the sialic acid family of carbohydrates. Sialic acids are a group of nine-carbon acidic monosaccharides that are commonly found on the surface of cells in vertebrates. Neu5Gc is one of the most abundant sialic acids in many mammalian species, playing significant roles in various biological processes.

Chemically, Neu5Gc differs from its closely related counterpart, N-acetylneuraminic acid (Neu5Ac), by a single hydroxyl group on the N-acetyl side chain. This seemingly small difference has important functional implications. In humans, Neu5Gc is typically not synthesized due to a genetic mutation that inactivates the enzyme CMP-N-acetylneuraminic acid hydroxylase (CMAH), which is responsible for converting Neu5Ac to Neu5Gc. Therefore, humans generally lack Neu5Gc in their own tissues.

However, humans can acquire Neu5Gc through the consumption of animal products, such as red meat and milk. This exogenous Neu5Gc can be incorporated into human tissues, a phenomenon known as "glycolyl-sialic acid accumulation." The presence of this foreign molecule in humans can elicit an immune response, leading to the production of anti-Neu5Gc antibodies. This immune reaction is of interest in the context of various diseases and conditions, including inflammation, cancer, and autoimmune disorders. Research into the biological significance and medical implications of Neu5Gc continues.