title: Isolation of tri-antennary enriched and tri-antennary depleted alpha-1-protease inhibitor.
abstract: Alpha-1-protease inhibitor, (alpha-1-PI), the major inhibitor of serine proteases in human plasma, has three asparagine-linked carbohydrate chains located at positions 46, 83 and 247. The protein has a microheterogeneity which is seen on isoelectric focusing and which is a result of whether the various carbohydrate chains are in bi- or tri-antennary forms. Tri-antennary enriched forms of alpha-1-PI are associated with inflammation. By using a combination of three methods, reductive salting out, Sepharose-bound Concanavalin A affinity chromatography, and Sepharose-bound anhydrochymotrypsin, biologically active alpha-1-PI was obtained in tri-antennary enriched and tri-antennary depleted forms. These preparations should be useful for studies on the physiological role of the carbohydrate moiety in alpha-1-PI.
mesh_terms: D001798:Blood Proteins / Q000302:isolation & purification*; D002241:Carbohydrates / Q000032:analysis; D006801:Humans; D007525:Isoelectric Focusing; D008970:Molecular Weight; D011480:Protease Inhibitors / Q000302:isolation & purification*; D013329:Structure-Activity Relationship; D000515:alpha 1-Antitrypsin
chemical_list: D001798:Blood Proteins; D002241:Carbohydrates; D011480:Protease Inhibitors; D000515:alpha 1-Antitrypsin