1. University of Hamburg, Biocenter Klein Flottbek, Department of Molecular Phytopathology, Hamburg, Germany
2. Oregon State University, Department of Biochemistry and Biophysics, Corvallis, Oregon, USA
3. Heinrich Pette Institute, Leibniz Institute for Experimental Virology, Hamburg, Germany
4. Oregon State University, Department of Chemistry, Corvallis, Oregon, USA