title: A simple method for the preparation and purification of C1 complement cleaved beta 2-microglobulin from human serum.
abstract: A simple method is described for the preparation of proteolytically processed forms of beta 2-microglobulin suitable for structural and biological studies. PEG 6000 was added to the serum of healthy individuals to precipitate the C1 complement complex from C1 esterase inhibitor (C1-inh). After dissolving the precipitate containing the C1 complement in Tris-HCl buffer, pH 7.6, efficient conversion of added beta 2-microglobulin to desLys58 beta 2-microglobulin was observed. Addition of a specific carboxypeptidase B inhibitor (Plummers inhibitor) could partly prevent the deletion of Lys-58 from cleaved beta 2-microglobulin, whereby Lys58-cleaved beta 2-microglobulin was obtained. The proteolytically processed forms were subsequently purified by G-75 Sephadex gel filtration followed by chromatofocusing. A yield of 10-40% of proteolytically processed beta 2-microglobulin was obtained. Only one component was seen by SDS-PAGE stained with Coomassie Brilliant Blue.
authors.affiliation: Institute of Medical Anatomy, Panum Institute, University of Copenhagen, Denmark.
authors.forename: M H
authors.initials: MH
authors.lastname: Nissen
authors.forename: B
authors.initials: B
authors.lastname: Johansen
authors.forename: O J
authors.initials: OJ
authors.lastname: Bjerrum
mesh_terms: D002850:Chromatography, Gel; D003172:Complement C1; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D001613:beta 2-Microglobulin / Q000302:isolation & purification*
chemical_list: D003172:Complement C1; D001613:beta 2-Microglobulin