Design and synthesis of metallopeptide sensors: Tuning selectivity with ligand variation

Abstract

We chose a fluorescent pentapeptide sensor (-CPGHE) containing a dansyl fluorophore as a model peptide and investigated whether the selectivity and sensitivity of the peptides for heavy and transition metal ions could be tuned by changing amino acid sequence. In this process, we developed a selective peptide sensor, Cp1-d (-HHPGE, Kd = 670 nM) for detection of Zn 2+ in 100% aqueous solution and a selective and sensitive peptide sensor, Cp1-e (-CCHPGE, Kb = 24 nM) for detection of Cd2+ in 100% aqueous solution. Overall results indicate that the selectivity and sensitivity of the metallopeptide sensors to specific heavy and transition metal ions can be tuned by changing amino acid sequence.