Investigating the Use of ¿¿-clamp Mediated Site-Selective Protein Modification to Create In Vivo Biosensors (2016)

Undergraduates: Jacob Smith, Nick Pinkin Nick Pinkin

Faculty Advisor: Klaus Hahn
Department: Chemistry

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Site-selective functionalization of proteins has been demonstrated using the four amino acid sequence (Phe-Cys-Pro-Phe) referred to as the ¿¿¿¿¿-clamp¿¿¿. The cysteine residue of the ¿¿-clamp motif readily undergoes nucleophilic aromatic substitution with perfluoroaryl probes. Dyes activated with thiol groups can be conjugated to proteins via SNAr reaction with the perfluoroaryl probe. We are investigating site selective modification of the protein Cdc42 in an attempt to create biosensors that can report protein activity in living cells. A merocyanine dye was chosen as a fluorescent label and fluorescence spectroscopy was used to determine the efficiency of protein labeling.