Martin-Luther-Universitat Halle-Wittenberg 1 article published in JoVE Bioengineering Residue-Specific Exchange of Proline by Proline Analogs in Fluorescent Proteins: How "Molecular Surgery" of the Backbone Affects Folding and Stability Tuyet Mai Thi To1, Vladimir Kubyshkin2, Franz-Josef Schmitt3, Nediljko Budisa1,2, Thomas Friedrich1 1Institute of Chemistry, Technische Universität Berlin, 2Department of Chemistry, University of Manitoba, 3Institute of Physics, Martin-Luther-Universität Halle-Wittenberg To overcome the limitations of classical site-directed mutagenesis, proline analogs with specific modifications were incorporated into several fluorescent proteins. We show how the replacement of hydrogen by fluorine or of the single by double bonds in proline residues ("molecular surgery") affects fundamental protein properties, including their folding and interaction with light.
