Versatile C-Terminal Specific Biotinylation of Proteins Using Both a Puromycin-Linker and a Cell-Free Translation System for Studying High-Throughput Protein-Molecule Interactions

摘要

Immobilization of a protein in a functionally active form and correct orientation for high-throughput analysis is crucial for surface-based protein--molecular interaction studies and should aid progress in associated nanotechnologies. Here, we present a general method for controlled and oriented immobilization of proteins by a puromycin-linker for cDNA display technology. The utility and potential of this method was demonstrated by examining the interaction between the B domain of protein A and immunoglobulin G (IgG) by surface plasmon resonance. This study revealed that the mRNA fragment of the mRNA-protein fusion (i.e., mRNA display) interferes with the interaction between the protein (B domain) and its target molecule (IgG). This results in a reduction of the apparent affinity by ～10-fold. This method is expected to find wide appeal in the fields of surface-based studies of protein--protein interactions, drug screening, and single molecule analysis that require only a small amount of protein sample.