1 | 0.4 mM [U-100% 13C; U-100% 15N; U-80% 2H] KCNQ1-VSD, 50 mM MES, 0.5 mM EDTA, 2 mM TCEP, 4 % w/v LMPG, 95% H2O/5% D2O | 13C-15N specific labeled sample was grown in M9 culture with 99% D2O. After purification, the sample was exchanged into 50 mM MES buffer (pH5.50), 5% D2O, 0.5 mM EDTA and 2 mM TCEP. | Q1-VSD 2H13C15N | 95% H2O/5% D2Omicelle2 | 0.4 mM [U-100% 13C; U-100% 15N] KCNQ1-VSD, 50 mM MES, 0.5 mM EDTA, 2 mM TCEP, 4 % w/v LMPG, 95% H2O/5% D2O | 13C-15N specific labeled sample was grown in M9 culture. After purification, the sample was exchanged into 50 mM MES buffer pH 5.50, 5% D2O, 0.5 mM EDTA and 2 mM TCEP. | Q1-VSD 13C15N | 95% H2O/5% D2Omicelle3 | 0.4 mM [U-100% 13C; U-100% 15N] KCNQ1-VSD, 50 mM MES, 0.5 mM EDTA, 2 mM TCEP, 4 % w/v Deuterated LMPG, 100% D2O | 13C-15N specific labeled sample was grown in M9. After purification, the sample was exchanged into 50 mM MES buffer (pH5.50), 5% D2O, 0.5 mM EDTA and 2 mM TCEP. Deuterated LMPG was used for this sample. | Q1-VSD 13C15N + deuterated LMPG | 100% D2Omicelle4 | 0.4 mM [U-100% 15N] KCNQ1-VSD, 50 mM MES, 0.5 mM EDTA, 2 mM TCEP, 4 % w/v LMPG, 95% H2O/5% D2O | 15N specific labeled sample was grown in M9. After purification, the sample was exchanged into 50 mM MES buffer (pH5.50), 5% D2O, 0.5 mM EDTA and 2 mM TCEP.Q1-VSD 15N | 95% H2O/5% D2Omicelle5 | 0.2 mM [U-100% 15N] KCNQ1-VSD, 50 mM MES, 0.5 mM EDTA, 2 mM TCEP, 4 mM LMPG, 95% H2O/5% D2O | 15N specific labeled sample was grown in M9. After purification, the sample was exchanged into 50 mM MES buffer (pH5.50), 5% D2O, 0.5 mM EDTA and 2 mM TCEP. Anisotropic sample was soaked into a 6 mm 5% gel and stretched into a 5 mm open ended NMR tube.Q1-VSD 15N anisotropic | 95% H2O/5% D2Omicelle6 | 0.2 mM [U-100% 15N] KCNQ1-VSD, 50 mM MES, 0.5 mM EDTA, 2 mM TCEP, 4 mM LMPG, 95% H2O/5% D2O | K121C-MTSL, C122S, C136A, C180S, C214A | Q1-VSD 15N K121C-MTSL | 95% H2O/5% D2Obicelle7 | 0.2 mM [U-100% 15N] KCNQ1-VSD, 50 mM MES, 0.5 mM EDTA, 2 mM TCEP, 4 % w/v LMPG, 95% H2O/5% D2O | T144C-MTSL, C122S, C136A, C180S, C214A | Q1-VSD 15N T144C-MTSL | 95% | | | | | | | | | | | | | | |