Donkey and horse alpha 1 B-glycoprotein: partial characterization and new alleles.

The research article revolves around the study of alpha 1 B-glycoprotein in donkeys and horses. The study further examines the characteristics of this particular protein including the terminal sialic acid content, isoelectric point, amino acid composition, and its affinity towards a specific dye. The research also discovered two additional alleles in the horse, expanding the total known to five.

Identification of alpha 1 B-Glycoprotein in Donkeys

• The study confirmed the presence of alpha 1 B-glycoprotein in donkeys, which was previously known to exist in humans. This finding was achieved through protein immunoblotting and N-terminal amino acid sequence.

Characterization of Horse and Donkey alpha 1 B-Glycoproteins

• The researchers further characterized the horse A1B system and donkey alpha 1 B-glycoprotein. They investigated several characteristics including the terminal sialic acid content, isoelectric point, amino acid composition, and the affinity of the proteins for a specific dye-ligand.
• The two proteins were found to have highly conserved N-terminal residues, confirming a strong phylogenetic relationship between the species.

New Alleles Found in Horses

• In studying the horse A1B system, researchers discovered two new alleles, bringing the total number identified to five. Nonetheless, they found no such polymorphism in the donkey’s alpha 1 B system.
• The researchers speculate that the polymorphism observed in horse alpha 1 B-glycoproteins may be related to differing numbers of terminal sialic acid residues.

Variations in Affinity for Dye-Ligand

• Both the horse and donkey’ alpha 1 B-glycoproteins showed differences in their affinity for the dye-ligand, Cibacron Blue F3GA. The donkey’s alpha 1 B-glycoprotein did not bind at all to the dye.
• The research also suggested that the greater electrophoretic mobility of the donkey’s alpha 1 B-glycoprotein could, in part, be attributed to increased sialylation.