1. Department of Cell and Molecular Biology, Section for Molecular Pathogenesis, Lund University, P.O. Box 94, S-221 00 Lund, Sweden
2. Department of Medical Microbiology, Lund University, Sölvegatan 23, S-223 62 Lund, Sweden
3. Institute for Physiological Chemistry and Pathobiochemistry, Johannes-Gutenberg-University at Mainz, Duesbergweg 6, D-55099 Mainz, Germany