Figure 1.

(a) GFP–polymer conjugates were synthesized by recombinant expression of a quaternary fusion protein, GFP–srt–His₆–ELP, followed by site–specific installation of an azido group at the C–terminus of GFP by sortase A–catalyzed native peptide ligation and subsequent copper–free click reaction with DBCO–terminated polymers. (b) Synthetic route of DBCO–terminated PEG–like biodegradable polycarbonate, nucleic acid–like biodegradable polyphosphoesters, phospholipid–like zwitterionic polymethacrylates, and PEG.