1. Institute of Biochemistry; Heinrich-Heine University Düsseldorf; Universitätsstrasse 1, Bldg. 26.42.U1 40225 Düsseldorf Germany
2. Institute of Complex Systems: Structural Biochemistry (ICS-6); Forschungszentrum Jülich GmbH; 52425 Jülich Germany
3. Institute of Theoretical and Computational Chemistry; Heinrich-Heine University Düsseldorf; Universitätsstrasse 1 40225 Düsseldorf Germany