1. Science for Life Laboratory, Department of Medicine Solna, Karolinska Institutet, and Department of Infectious Diseases; Karolinska University Hospital; Solna Stockholm SE 17176 Sweden
2. Departments of Chemistry and Biochemistry; University of Notre Dame; Notre Dame IN 46556 USA
3. Department of Microbiology, Tumor and Cell Biology; Karolinska Institutet; Stockholm 171 77 Sweden
4. Department of Clinical Microbiology; Karolinska University Hospital; Solna Stockholm 17176 Sweden