Immunochemical properties of human plasma alpha 1 leads to 2 fucosyltransferase specified by blood group H-gene.

A beta-galactoside alpha 1 leads to 2 fucosyltransferase (H-enzyme) from human group O plasma which provides H blood group specificity to erythrocyte membranes has been purified approximately 22,000-fold by chromatography on DEAE-Sepharose CL-6B, GDP-hexanolamine-Sepharose 4B and SP-Sephadex C-50. The molecular weight of the H-enzyme was estimated to be 150,000 by gel filtration. Human group O erythrocyte membranes which had lost their H blood group activity by the action of alpha 1 leads to 2 fucosidase were fucosylated by the transferase, and restored the H activity. Radioactive L-fucose appeared to be incorporated into glycolipid blood group substances of erythrocyte membranes. The activity of the alpha 1 leads to 2 fucosyltransferase from human plasma, stomach mucosa, erythrocyte membranes and porcine stomach mucosa were specifically inhibited by the rabbit antiserum immunized with the preparation of human plasma H-enzyme. The anti-plasma H-enzyme antiserum did not inhibit the activities of alpha 1 leads to 3 N-acetylgalactosaminyltransferase (A-enzyme), alpha 1 leads to 3 galactosyltransferase (B-enzyme), and beta-N-acetylglucosaminide alpha 1 leads to 3 and alpha 1 leads to 4 fucosyltransferases from human plasma and stomach mucosa.