Genetically Encoded Dihydroxyphenylalanine Coupled with Tyrosinase for Strain Promoted Labeling

Abstract

The newly developed molecular biology approach expanding the genetic code was used to incorporate the non-canonical amino acid dihydroxyphenylalanine for fine-tuning of proteins. Further, the congener protein was enzymatically converted to form quinone for strain promoted click chemistry. The reaction yields a single product with defined stereochemistry and temporally controlled conjugation with bicyclonon[6.1.0]-4-yne (BCN) as well as dibenzocyclooctyne-PEG-Fluor 545. The promising bioconjugation of congener protein with dibenzocyclooctyne-PEG-Fluor 545 was used as a fluorescent marker for selective cell imaging and detection of programmed cell death in EAhy926 cells.