1. The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research (UCMR), Department of Molecular Biology, Umeå University, Umeå S-90187, Sweden, 2Helmholtz Centre for Infection Research, Department of Regulation in Infection Biology, Braunschweig D-38124, Germany, 3Deptartment of Biochemistry and Cell Biology, Max F. Perutz Laboratories, University of Vienna, Vien