Blood-group active glycolipids

Marcus, D. M., Cass, L., Glycolipids with Lewis Blood Group Activity, ... 

Table I. Some Characteristics of Different Compartments of Rat Small Intestine. The Blood Group Activities Concern Glycolipid Fractions.

Advances in glycolipid chemistry include the isolation of new types of gangliosides from human erythrocyte membranes and the elucidation of information on their blood-group activities. The importance of polyisoprenol-sugar derivatives continues to attract much effort and the enzyme work on rat liver and yeast membranes are worth consideration. Another advance is the discovery that neuraminidases which are also able to hydrolyse the appropriate bond in the ganglioside Gmi do exist. This bond was thought to be resistant to enzymic attack due to steric hindrance. 

Fucolipids are present in both compartments. However, the blood group B active compound of non-epithelial cells (absent in epithelial cells) is based on GalNAc while the H and A active substances specific for epithelial cells have GlcNAc in their core saccharide. In fact, GlcNAc seems to be absent from all non-epithelial glycolipids. The minor fucolipid based on tetrahexosyl-ceramide (as indicated in fraction B of Fig. 5) was obtained from pooled tissue. This glycolipid has been shown to be located in the epithelial cells. 

Different glycolipid fucosyltransferase activities have been reported (32,55,58) to catalyze the addition of fucose to position C-2 of the terminal D-galactose and position C-3 of the internal N-acetylglucosamine of nLcOse4Cer to form blood group H or human tumor-specific lipid (10). Incorporation of fucose into GgOse4Cer was also reported recently by Taki et al. 

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