Folding of the Fab fragment within the intact antibody

FEBS Letters

Lilie, Hauke¹ 

[1] Institut für Biotechnologie, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes Strasse 3, 06120 Halle, Germany

关键词: Antibody;    Fab fragment;    Denaturation;    Renaturation;    Folding intermediate;    Fab;    Fab fragment of an antibody consisting of the entire light chain and the two N-terminal domains of the heavy chain;    Fab′;    proteolytically derived antibody fragment consisting of two Fab fragments covalently linked by disulfide bonds within the hinge region;    MAK 33;    intact murine monoclonal antibody (κ/IgG1);    GdmCl;    guanidinium chloride;   

DOI  :  10.1016/S0014-5793(97)01293-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

At present it is not clear to which extent the Fab fragment and the Fc part of an antibody interact in the intact immunoglobulin structure. To determine such potential interactions the unfolding and refolding of an isolated Fab fragment and the respective antibody MAK 33 (κ/IgG1) are compared. It could be shown that the proline independent renaturation kinetics of both an unfolding intermediate and the fully denatured form of both proteins are identical. Upon denaturation, the loss of antigen binding activity occurs with the same rate for both the Fab fragment and the intact antibody. However, the complete structural unfolding of the Fab part of the antibody is significantly slower than that of the isolated Fab fragment. These kinetic data suggest that the structure of the Fab fragment within the intact antibody is stabilized by interactions, presumably with the Fc part, missing in the isolated Fab.

【 授权许可】

Unknown