1. Centre of Microbial and Plant Genetics University of Leuven 3001 Heverlee Belgium
2. Research Group Microbiology Department of Bioengineering Sciences Vrije Universiteit Brussel 1050 Brussels Belgium
3. Department of Structural Biology VIB 1050 Brussels Belgium
4. Laboratory for Molecular and Cellular Technology Queen Astrid Military Hospital 1120 Brussels Belgium