Site-Specific, Covalent Labeling of Recombinant Antibody Fragments via Fusion to an Engineered Version of 6-O-Alkylguanine DNA Alkyltransferase

Citations Over TimeTop 10% of 2009 papers

Abstract

Recombinant antibodies are promising tools for a wide range of bioanalytical and medical applications. However, the chemical modification of such molecules can be challenging, which limits their broader utilization. Here we describe a universal method for the site-specific labeling of antibody fragments and protein ligands by genetically fusing them to an engineered version of the human DNA-repair enzyme O(6)-alkyllguanine DNA alkyltransferase (AGT), known as SNAP-Tag (1-3) . Substrates containing O(6)-benzylguanine are covalently bound to the fusion proteins via a stable thioether bond in a rapid and highly specific self-labeling reaction. The coupling is site-directed, allowing the design and synthesis of antibody conjugates with predefined stoichiometry. We cloned a series of ligand SNAP-Tag fusion proteins and expressed them in HEK 293T cells. The antibody/ligand-fusions were characterized by labeling with different fluorophores, labeling with biotin, or by coupling them to fluorescent nanobeads, followed by analysis by flow cytometry and confocal microscopy. All ligands retained their original antigen-binding properties when fused to the SNAP-Tag. The combination of recombinant antibodies or protein ligands with the SNAP-Tag facilitates simple and efficient covalent modification with a broad range of substrates, thus providing a useful and advantageous alternative to existing coupling strategies.

Related Papers

• Effect of Temperature on the Growth of Recombinant E.coli and on the Expression of Recombinant Protein(2002)
• → A Convenient Method for Solubilization and Refolding Recombinant Proteins: An Experience from Recombinant Mouse TGF-β1(2020)2 cited
• → Early Detection of the Recombinant SARS-CoV-2 XAN Variant in Bulgaria: Initial Genomic Insights into Yet Another Piece of the Growing Puzzle of Recombinant Clades(2023)1 cited
• [Expression of recombinant human ZP3 protein using the baculovirus expression system].(2014)
• → Recombinant Proteins in Diagnosis and Therapy(2009)