1. Institute of Microbiology, v.v.i., Czech Academy of Sciences, Videnska 1083, 142 20 Praha 4, Czech Republic
2. Department of Genetics and Microbiology, Faculty of Science, Charles University in Prague, Vinicna 5, 128 00 Praha 2, Czech Republic
3. Institute of Microbiology, v.v.i., BIOCEV, Czech Academy of Sciences, 252 50 Vestec, Czech Republic
4. Laboratory of Structural Biology and Maurice Wilkins Center for Molecular Biodiscovery, School of Biological Sciences, University of Auckland, Auckland 1010, New Zealand