Receptor‐binding domain of human α2‐macroglobulin Expression, folding and biochemical characterization of a high‐affinity recombinant derivative

FEBS Letters

Nielsen, Kåre Lehmann¹  Etzerodt, Michael¹  Sottrup-Jensen, Lars³  Gliemann, Jørgen²  Moestrup, Søren Kragh²  Thøgersen, Hans Christian¹  Holtet, Thor Las¹ 

[1]Laboratory of Gene Expression, Department of Chemistry, University of Århus, DK-8000 Århus C, Denmark

[2]Department of Medical Biochemistry, University of Århus, DK-8000 Århus C, Denmark

[3]Department of Molecular Biology, University of Århus, DK-8000 Århus C, Denmark

关键词: α-Macroglobulin;    Domain structure;    Protein expression;    α2-Macroglobulin receptor;    α2M;    α2-macroglobulin;    α2MR/LRP;    receptor for transformed α2-macroglobulin/low density lipoprotein receptor-related protein;    α2M-MA;    methylamine-treated α2-macroglobulin;    RBD;    receptor binding domain of α2-macroglobulin (Glu1314-Ala1451);    RBDv;    expressed variant of receptor binding domain (Val1299-Ala1451);    PCR;    polymerase chain reaction;    SDS-PAGE;    sodium dodecylsulfate polyacrylamide gel electrophoresis;    NTA;    nitrilo triacetic acid;   

DOI  :  10.1016/0014-5793(94)00349-1

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A recombinant version of the receptor binding domain (RBDv) of human α₂-macroglobulin (α₂M) has been expressed in E. coli and refolded using a novel iterative procedure. RBDv (Val¹²⁹⁹-Ala¹⁴⁵¹) is extended by 15 residues at the N-terminal side of the Lys¹³¹³-Glu papain cleavage site in human α₂M. RBDv contains the intra-chain bridge Cys¹³²⁹-Cys¹⁴⁴⁴ and is soluble and monomeric. Competition experiments with ¹²⁵I-labelled methylamine-treated α₂M reveal that RBDv binds to the placental receptor for transformed α₂M with a K _d of 8 nM, i.e. the binding affinity of RBDv is of the same order of magnitude as the intrinsic affinity for binding of one domain in transformed α₂M to one receptor molecule.

【 授权许可】

Unknown