1. Biological Chemistry, Biomedical Sciences Division, Faculty of Natural Sciences, Imperial College London, Sir Alexander Fleming Building, South Kensington, London, SW7 2AZ, United Kingdom, State Key Laboratory of Magnetic Resonance and Molecular and Atomic Physics, Wuhan Institute of Physics and Mathematics, The Chinese Academy of Sciences, Wuhan, 430071, Peoples Republic of China, and Nestlé Research Center, Lausanne, NESTEC Ltd., Vers-Chez-Les-Blanc, 1000 Lausanne 26, Switzerland