International Journal of Molecular Sciences Article Computational Aminoacyl-tRNA Synthetase Library Design for Photocaged Tyrosine 1, 1, 2, 3 2,4 Tobias Baumann y , Matthias Hauf y, Florian Richter z, Suki Albers , Andreas Möglich , Zoya Ignatova 3 and Nediljko Budisa 1,5,* 1 Institut für Chemie, Technische Universität Berlin, Müller-Breslau-Straße 10, 10623 Berlin, Germany;
[email protected] (T.B.);
[email protected] (M.H.) 2 Biophysikalische Chemie, Institut für Biologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany; fl
[email protected] (F.R.);
[email protected] (A.M.) 3 Institute of Biochemistry and Molecular Biology, University of Hamburg, 20146 Hamburg, Germany;
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[email protected] (Z.I.) 4 Lehrstuhl für Biochemie, Universität Bayreuth, 95447 Bayreuth, Germany 5 Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2, Canada * Correspondence:
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[email protected]; Tel.: +49-30-314-28821 or +1-204-474-9178 These authors contributed equally to this manuscript. y Present address: Bayer AG, Pharmaceuticals, Protein Engineering and Assays, Nattermannallee 1, z 50829 Köln, Germany. Received: 16 April 2019; Accepted: 9 May 2019; Published: 11 May 2019 Abstract: Engineering aminoacyl-tRNA synthetases (aaRSs) provides access to the ribosomal incorporation of noncanonical amino acids via genetic code expansion. Conventional targeted mutagenesis libraries with 5–7 positions randomized cover only marginal fractions of the vast sequence space formed by up to 30 active site residues. This frequently results in selection of weakly active enzymes. To overcome this limitation, we use computational enzyme design to generate a focused library of aaRS variants.