Synthetic Biology of Autofluorescent Proteins

  • Michael Georg Hoesl
  • Lars Merkel
  • Nediljko BudisaEmail author
Part of the Springer Series on Fluorescence book series (SS FLUOR, volume 11)



Autofluorescent proteins (FPs), which to date are predominately used as tools in cell biology and spectroscopy, have arrived in the focus of synthetic biology. Thereby, the intention is to supplement classically used protein design methods such as site-directed mutagenesis or guided evolution by expanding the scope of protein synthesis. This is achieved by the co-translational introduction of novel noncanonical amino acids (NCAAs) into proteins. In the following chapter, we present current applications of an expanded amino acid repertoire for the design of spectral and folding properties of FPs. We will show that NCAAs are not only useful tools to study fundamental aspects of photophysics but also have great potential to generate novel FP tools for cell biology applications. On the one hand, aromatic amino acids other than the naturally occurring His, Tyr, Phe, and Trp were used to create novel spectral classes of FPs by direct chromophore modification. On the other hand, NCAAs were also applied for “FP protein matrix engineering” to influence chromophore fluorescence and overall folding. We also illustrate a practical application of these principles by presenting “golden annexin A5” as a novel apoptosis detection tool designed by synthetic biology methods. Finally, we describe a potential route to convert any protein of interest into a chromo-protein by introduction of novel synthetic autofluorescent amino acids.

Graphical Abstract


Chromophore variants ECFP EYFP GFP GFP structure non-canonical amino acid synthetic biology 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Michael Georg Hoesl
    • 1
  • Lars Merkel
    • 1
  • Nediljko Budisa
    • 1
    Email author
  1. 1.Department of ChemistryBerlin Institute of Technology/TU Berlin, Biocatalysis GroupBerlinGermany

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