Site-Specific Labeling of Native Peptides and Proteins: Chemical and Enzymatic Strategies

Site-specific modifications of native-sequence proteins are technologies that underpin progresses in chemical biology, diagnostics and next-generation biotherapeutics. However, the pursuit of site-specificity has often come at the expense of scalability and usability, ultimately limiting translational potential of a modification tool. This review critically compares current key strategies, including terminal, disulfide rebridging, small-molecule, glycan and enzyme-based modifications. Finally, we present a decision tree to guide method selection and highlight opportunities for innovation in next-generation native-sequence protein modification technologies.