Open AccessStudies on Blood‐Groups A Enzymes. 1 and A 2
Author(s) -
SCHENKELBRUNNER Helmut
Publication year - 1982
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1982.tb06466.x
Subject(s) - glycolipid , transferase , enzyme , fractionation , glycoprotein , microbiology and biotechnology , biochemistry , stroma , chemistry , galactosamine , oligosaccharide , biology , chromatography , immunology , immunohistochemistry , glucosamine
Blood‐group O and A 2 erythrocytes were treated with the A 1 ‐gene‐dependent and A 2 ‐gene‐dependent N ‐acetylgalactosaminyl transferases in the presence of UDP‐ N ‐acetyl[ 14 C]galactosamine. Although the transfer of N ‐acetyl[ 14 C]galactosarnine with A 2 transferase was slower than with A 1 enzyme, group O as well as A 2 cells became agglutinable by anti‐A 1 reagents when incubated with both transferases. Fractionation of the labelled erythrocyte stroma into glycoprotein and glycolipid components showed an approximately equal distribution pattern of radioactivity in all experiments. Likewise, when the short‐chain glycolipids and polyglycosylceramides isolated from the labelled stroma were further analyzed by thin‐layer chromatography, no major differences were detected in the chromatographic profiles of O and A 2 cells when treated with either transferase. These observations indicate that (a) the blood‐group‐H‐type oligosaccharide chains of A 2 cells may be similar to those of group‐O cells and (b) the serological differences between A 1 and A 2 cells are likely to be due to a lower density of A‐antigenic sites on A 2 cells.