Glycolipids of Mammalian Red Blood Cells

Abstract

In 1951, a glycolipid called ‘hematoside’ was isolated in appreciable amount from equine erythrocyte stroma (Yamakawa and Suzuki). It gave a beautiful purple color when heated with Bial’s orcinol reagent, thus indicating the probable presence of neuraminic acid. Neuraminic acid was known, at that time, as a constituent of ganglioside and considered to be a polyhydroxyamino acid having the molecular formula of C₁₁H₂₁O₉N or C₁₀H₁₉O₈N (Klenk, 1941). In those days, ganglioside, which Klenk and co-workers had isolated from the brain of patient with Tay-Sachs disease (Klenk, 1935) and from bovine spleen (Klenk and Rennkamp, 1942) was said to consist of stearic acid, sphingosine, 3 moles of hexose (glucose and galactose) and neuraminic acid (Klenk, 1942), though the presence of hexosamine in bovine brain was already reported by Blix (1938). Afterward, galactosamine was isolated by Blix, Svennerholm and Werner (1950) from a brain ganglioside preparation, but it seems they doubted the presence of neuraminic acid and regarded it as a degradation product of a crystalline disaccharide-like polyhydroxyamino acid, which BLIX had previously found in submaxillary mucin in 1936 and later named ‘sialic acid’ (Blix, Svennerholm and Werner, 1952). This rather complicated situation was clearly understood when both neuraminic acid and galactosamine were found in ganglioside preparation (Klenk, 1951).