[1] European Mol Biol Lab, D-69117 Heidelberg, Germany
[2] Univ London Imperial Coll Sci Technol & Med, Dept Biol Sci, Ctr Mol Microbiol & Infect, London SW7 2AZ, England
[3] Cellzome, D-69117 Heidelberg, Germany
[4] Yale Univ, Dept Genet, Sch Med, New Haven, CT 06520 USA
[5] Colorado State Univ, Dept Pathol, Ft Collins, CO 80523 USA