1. Department of Chemistry, New York University, New York, New York 10003, United States
2. Department of Chemistry, Ludwig Maximilian University, Munich D-80539, Germany
3. Department of Neurosurgery, Stanford University School of Medicine, Stanford, California 94305, United States
4. Institute for Synaptic Physiology, ZMNH, University Medical Center Hamburg-Eppendorf, Hamburg D-20251, Germany
5. Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York 10032, United States
6. Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
7. Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States