![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
Abstract
Ceruloplasmin is a blue copper-containing serum glycoprotein with oxidase activity. It as been proposed that the physiological function of ceruloplasmin involves the oxidation of ferrous iron and its incorporation into apotransferrin (1). There are several reports demonstrating that ceruloplasmin is made up of multiple chains (2-3-4-5-6-7). Ryden (8) has questioned the multichain structure of ceruloplasmin from human, pig, horse and rabbit sera, arguing that the dissociation observed by previous workers could be attributed to cleavage of labile bands in the protein by enzymatic contaminants present in commercial preparations of the protein. By introducing aminocaproic acid, a general protease inhibitor, at the beginning of the enzyme preparation, Ryden proposed a single-chain structure for ceruloplasmin. On the contrary the results presented by Freeman and Daniel (9) showed that human ceruloplasmin is a multichain protein.
In this paper we report a new purification method for horse ceruloplasmin which furnishes a homogeneous protein preparation in high yield and with good reproducibility.
This procedure allowed to determine with greater accuracy the molecular mass of the protein, of 120000 dal-tons by gel cromatography and 115000 daltons by SDS gel electrophoresis. The protein is composed of one unit only and contains 6 copper atoms. Horse cerulopla-smin is a glycoprotein containing about 20% carbohydrate by weight.