Abstract: A method for improving a bio-coupling efficiency between a protein and a nucleic acid based on an ?-helix handle includes the following steps. First, the handle carrying the non-natural amino acid (H-tag) is designed. Then, a recombinant expression plasmid encoding a fusion protein containing the H-tag and the protein to be tested is constructed. Subsequently, the fusion recombinant protein containing the non-natural amino acid in the H-tag is expressed and purified. Finally, the non-natural amino acid in the H-tag-fused protein and the coupling group on the nucleic acid substrate are efficiently connected by click chemistry. Thea-helix handle is used to provide a controllable reaction condition on the protein surface for the non-natural amino acid, avoiding the complex structure, charge and polar nanoenvironment around the surface of the protein to be tested.

Abstract: A method for improving a bio-coupling efficiency between a protein and a nucleic acid based on an ?-helix handle includes the following steps. First, the handle carrying the non-natural amino acid (H-tag) is designed. Then, a recombinant expression plasmid encoding a fusion protein containing the H-tag and the protein to be tested is constructed. Subsequently, the fusion recombinant protein containing the non-natural amino acid in the H-tag is expressed and purified. Finally, the non-natural amino acid in the H-tag-fused protein and the coupling group on the nucleic acid substrate are efficiently connected by click chemistry. Thea-helix handle is used to provide a controllable reaction condition on the protein surface for the non-natural amino acid, avoiding the complex structure, charge and polar nanoenvironment around the surface of the protein to be tested.