1. Department of Biophysics Centre of the Region Haná for Biotechnological and Agricultural Research Faculty of Science Palacký University Šlechtitelů 27 783 71 Olomouc Czech Republic
2. Centre of the Region Haná for Biotechnological and Agricultural Research Institute of Experimental Botany Šlechtitelů 31 783 71 Olomouc Czech Republic
3. Electron Microscopy Group Groningen Biomolecular Sciences and Biotechnology Institute University of Groningen Nijenborgh 7 9747 AG Groningen the Netherlands