1. AG Biopolymerspektroskopie, Max-Delbrück-Centrum für Molekulare Medizin Berlin-Buch, Robert-Rössle-Straβe 10, D-13092 Berlin, Germany; Institute of Biological Chemistry, Academia Sinica, 128 Academia Road, Sec. 2, Nankang, Taipei 115, Taiwan; and Department of Chemistry, National Taiwan University, Taipei 106, Taiwan