A Single Bioorthogonal Reaction for Multiplex Cell Surface Protein Labeling.

ABSTRACT: Small-molecule fluorophores are invaluable tools for fluorescence imaging. However, means for their covalent conjugation to the target proteins limit applications in multicolor imaging. Here, we identify 2-[(alkylthio)(aryl)methylene]malononitrile (TAMM) molecules reacting with 1,2-aminothiol at a labeling rate over 10⁴ M^-1 s^-1 through detailed mechanistic investigation. The fast TAMM molecules and mild reaction conditions enable site-specific labeling of surface proteins in not only cell lines but also primary neurons and living mice. The combination of genetic code expansion and sequence-specific proteolytic cleavage enables selective modification of three different cell surface proteins through iterative TAMM condensation. TAM

SUBMITTER: Huang Y 

PROVIDER: S-EPMC11744750 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature