title: The isolation and characterization of a new elastase inhibitor, pre-alpha 2-elastase inhibitor, of the horse.
abstract: A new and probably unique elastase inhibitor of horse serum was identified, purified to homogeneity and called pre-alpha 2-elastase inhibitor of the horse. Electrophoretically it migrated immediately in front of the alpha 2 position. Its molecular weight was 188 000 by pore limit polyacrylamide gel electrophoresis and 225 000 by Sephadex G-200 gel filtration. The inhibitor was composed of at least two non-identical polypeptide chains of Mr 68 400 and 87 600. A banding pattern of restricted heterogeneity focused between pH 4.9 and 5.2 was revealed by isoelectric focusing. Of 13 animal, microbial and plant proteinases, horse pre-alpha 2-elastase inhibitor inhibited only pancreatic elastase and trypsin efficiently. Chymotrypsin was inhibited only in traces. No analogy between the elastase inhibitor and the known human serum inhibitors could be found with respect to immunological and biochemical criteria.
mesh_terms: D000818:Animals; D002850:Chromatography, Gel; D003429:Cross Reactions; D004587:Electrophoresis, Agar Gel; D006736:Horses; D007525:Isoelectric Focusing; D046911:Macromolecular Substances; D008970:Molecular Weight; D010196:Pancreatic Elastase / Q000037:antagonists & inhibitors*; D011480:Protease Inhibitors / Q000276:immunology / Q000302:isolation & purification*
chemical_list: D046911:Macromolecular Substances; D011480:Protease Inhibitors; D010196:Pancreatic Elastase