Open Accessα‐ D ‐Galactosidase from Soybeans Destroying Blood‐Group B Antigens
Author(s) -
HARPAZ Noam,
FLOWERS Harold M.,
SHARON Nathan
Publication year - 1977
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1977.tb11682.x
Subject(s) - blood group antigens , antigen , chemistry , food science , microbiology and biotechnology , biology , immunology
α‐ D ‐Galactosidase was isolated from untoasted soybean meal and purified to homogeneity by affinity chromatography on N ‐ɛ‐aminoacaproyl α‐ D ‐galactopyranosylamine‐Sepharose. The purified enzyme destroyed the B‐specificity of human ovarian cyst B‐glycoprotein with an accompanying increase in H‐specificity, and converted human type‐B erythrocytes to type O. The enzyme consists primarily of a tetramer, molecular weight 150000 ± 5000 at pH 4.0, and of a monomer, molecular weight 40000 ± 3000 at pH 8.0. Polyacrylamide gel electrophoresis in dodecyl sulfate at pH 7.2 distinguished between two types of monomeric unit of similar molecular weight. N‐terminal alanine was identified as the sole N‐terminal amino acid residue. The enzyme was shown to be devoid of carbohydrate.