1. Biocatalysis, Institute of Biotechnology RWTH Aachen University Worringerweg 3 52074 Aachen Germany
2. Department of Biochemistry Groningen Biomolecular Sciences and Biotechnology Institute University of Groningen Nijenborgh 4 9747 AG Groningen Netherlands
3. Institute for Biochemistry, Biotechnology and Bioinformatics Technische Universität Braunschweig Spielmannstr. 7 38106 Braunschweig Germany
4. Structure and Function of Proteins Helmholtz Centre for Infection Research Inhoffenstr. 7 38124 Braunschweig Germany