Novel affinity tag system using structurally defined antibody‐tag interaction: Application to single‐step protein purification

Abstract

Biologically important human proteins often require mammalian cell expression for structural studies, presenting technical and economical problems in the production/purification processes. We introduce a novel affinity peptide tagging system that uses a low affinity anti‐peptide monoclonal antibody. Concatenation of the short recognition sequence enabled the successful engineering of an 18‐residue affinity tag with ideal solution binding kinetics, providing a low‐cost purification means when combined with nondenaturing elution by water‐miscible organic solvents. Three‐dimensional information provides a firm structural basis for the antibody–peptide interaction, opening opportunities for further improvements/modifications.