Fig. 6: α2-Macroglobulin also exists in multiple disulfide-bonded states in the circulation.
From: Fibrinogen function achieved through multiple covalent states
a α2-Macroglobulin was isolated and processed from the same healthy donor plasmas as described for fibrinogen in Fig. 1. Shown is a representative 12C-IPA-labeled α2-macroglobulin resolved on SDS-PAGE. Molecular mass standards are shown in the left-hand lane. α2-Macroglobulin is a homo-tetramer with a molecular mass of 720 kDa. b Redox states of the 12 α2-macroglobulin disulfide bonds in eight healthy human donors (five female—solid symbols; three male—open symbols). The bars and errors are mean ± SD. Bonds indicated by yellow bars are <20% reduced, salmon bars 20–40% reduced and the red bar >40% reduced. Source data are provided as a Source Data file. c Ribbon structure of α2-macroglobulin and the positions of the 12 disulfide bonds (spheres)19 (PDB identifier 4acq). The disulfide colour matches the coding in part B. The C278-C431 disulfide is cleaved in this structure, while the other 11 disulfide bonds are intact.
