1. Faculty of Pharmacy, University of Ljubljana, 1000 Ljubljana, Slovenia
2. Enveloppes Bactériennes et Antibiotiques, IBBMC, UMR 8619 CNRS, Université Paris-Sud 11, 91405 Orsay, France
3. Institut de Biologie Structurale, J. P. Ebel, CEA, CNRS, UJF, UMR5075, F-38027 Grenoble, France
4. Medical Faculty, Institute of Microbiology and Immunology, University of Ljubljana, 1105 Ljubljana, Slovenia