[1] Max Planck Inst Mol Physiol, D-44139 Dortmund, Germany
[2] Ctr Appl Chem Genom, Dortmund, Germany
[3] Tech Univ Dortmund, Dortmund, Germany
[4] DESY, Max Planck Unit Struct Mol Biol, D-22607 Hamburg, Germany
[5] Tech Univ Darmstadt, Clemens Schopf Inst Organ Chem & Biochem, D-64287 Darmstadt, Germany