Engineering of an Fc-specific monovalent protein G for the light-controlled affinity purification of antibodies.

ABSTRACT: Like other widely applied bacterial surface receptor proteins for immunoglobulins (Igs), such as protein A and protein L, the Ig-binding domain of protein G (ProtG) has dual binding activity. ProtG can independently associate both with the Fc region of an antibody (mAb) and with its Fab and, thus, provoke cross-linking if applied in solution. Indeed, we observed pronounced precipitation activity when using ProtG equipped with the Azo-tag as a small adapter molecule for the light-controlled affinity purification of mAbs. We demonstrate that this undesired precipitation phenomenon follows the classical Heidelberger-Kendall curve. Furthermore, we describe a mutant of ProtG in which Asn478 at the interface with the Fab is replaced by Arg, which results in the effective loss of this secondary b

SUBMITTER: Mayrhofer P 

PROVIDER: S-EPMC12579241 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature