1. Helmholtz Institute for Pharmaceutical Research Saarland (HIPS)Helmholtz Center for Infection Research (HZI) Saarbrücken 66123 Germany
2. Department of PharmacySaarland University Saarbrücken 66123 Germany
3. Institute of Medical Microbiology and HygieneSaarland University Homburg 66421 Germany
4. Institute for New MaterialsSaarland University Saarbrücken 66123 Germany
5. School of Pharmacy and Biomolecular SciencesJohn Moores University Liverpool L3 3AF UK