Unit of Microbiology, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium. mohamed.mysara@sckcen.be.|Unit of Microbiology, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium. natalie.leys@sckcen.be.|Department of Bioscience Engineering, Vrije Universiteit Brussel, Brussels, Belgium. jeroen.raes@gmail.com.|Unit of Microbiology, Belgian Nuclear Research Centre (SCK CEN), Mol, Belgium. pieter.monsieurs@sckcen.be.