Construction of ribonucleopeptide-based fluorescent sensors for biologically active amines

Fluorescent biosensors are expected to be utilized for a wide range of applications, such as diagnostic and pharmacological tools. However, fluorescent biosensors synthesized by the direct coupling between the ligand bindings and optical signalling events are not always guaranteed to execute the expected optical signals. Our strategy of the stepwise molding using a framework of ribonucleopeptide (RNP) provides fluorescent biosensors with a variety of binding and signal-transducing characteristics for small molecules. RNP-based fluorescent sensors were created with a combination of in vitro selection method and a successive modification of the peptide of RNP with a fluorophore. The RNP containing the fluorophore labeled peptide subunit showed a remarkable fluorescence emission change upon binding to biologically active amines.