1. Unit of Microbiology, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, 2400 Mol, Belgium
2. Department of Bio-Engineering Sciences, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussel, Belgium
3. VIB Center for the Biology of Disease, VIB, Herestraat 49 - box 1028, 3000 Leuven, Belgium
4. Department of Microbiology and Immunology, REGA institute, Herestraat 49 - box 1028, 3000 Leuven, Belgium