Characterization of dog small intestinal fucolipids with human blood group A activity. Differences in dog and human A-active fucolipids

Abstract

Glycolipids containing fucose (fucolipids) which carried human blood group A activity were isolated from a number of dog small intestines and analyzed. On the basis of sugar analysis, methylation, periodate oxidation, enzyme degradation, mass spectrometry and immunologic studies, a structure is proposed for these substances. The ceramides of the dog fucolipids contained only hydroxylated fatty acids with 85% saturated and 15% monoenoic acids ranging from 16-25 C atoms. Sphingosine and phytosphingosine comprised 48% each of the long chain bases. An A-active fraction isolated from human small intestine had 2 components, one of which was immunologically distinct and the other identical with the dog intestinal fucolipids. The human fraction differed from the dog fucolipids in migration on TLC chromatography and contained 2 types of amino sugar substitution. It is proposed that the human fraction was composed of 2 fucolipids with incomplete structures.