[1] Univ Munich, Inst Physiol Chem, D-81377 Munich, Germany
[2] Univ Munich, Ctr Integrated Prot Sci, D-81377 Munich, Germany
[3] Tel Aviv Univ, George S Wise Fac Life Sci, Dept Biochem, IL-69778 Tel Aviv, Israel
[4] Max Planck Inst Biochem, D-82152 Martinsried, Germany