1. Department of Biological Chemistry Institute for Advanced Chemistry of Catalonia, IQAC-CSIC Jordi Girona 18–26 08034 Barcelona Spain
2. NMR Facility Institute for Advanced Chemistry of Catalonia, IQAC-CSIC Jordi Girona 18–26 08034 Barcelona Spain
3. Department of Physiology and Biophysics Stony Brook University and Department of Veterans Affairs Medical Center Stony Brook NY, 11794 USA