2L0J

Solid State NMR structure of the M2 proton channel from Influenza A Virus in hydrated lipid bilayer


SOLID-STATE NMR
NMR Experiment
ExperimentTypeSample ContentsSolventIonic StrengthpHPressureTemperature (K)Spectrometer
1PISEMA5-15 mM [U-15N] entity-1, 5-15 mM [U-15N]-Leu entity-2, 5-15 mM [U-15N]-Ile entity-3, 5-15 mM [U-15N]-Val entity-4, 5-15 mM [U-15N]-Phe entity-5100% H2O107.5ambient303
2PISEMA5-15 mM [U-15N] entity-1, 5-15 mM [U-15N]-Leu entity-2, 5-15 mM [U-15N]-Ile entity-3, 5-15 mM [U-15N]-Val entity-4, 5-15 mM [U-15N]-Phe entity-5100% H2O107.5ambient303
NMR Spectrometer Information
SpectrometerManufacturerModelField Strength
1BrukerAvance600
2BrukerAvance900
3BrukerDRX400
NMR Refinement
MethodDetailsSoftware
simulated annealing and molecular dynamics, molecular dynamicsMonomer structure was calculated using solid state NMR constraints by simulated annealing. A preliminary model for tetramer was assembled placing four copies of monomer consistent with NMR derived tilt angles and rotation. The model was annealed again by incorporating distance and orientational restraints.The tetramer model was placed in explicit hydrated lipid bilayer and tetramer model was refined with solid state NMR orientational restraints using NAMD. Finally, The His37-Trp41 geometry was optimized using QM/MM calculations keeping backbone fixed. Note the His-His geometry is consistent with the experimental NMR observation.X-PLOR_NIH
NMR Ensemble Information
Conformer Selection Criteriastructures with the least restraint violations
Conformers Calculated Total Number8
Conformers Submitted Total Number8
Representative Model1 (fewest violations)
Computation: NMR Software
#ClassificationVersionSoftware NameAuthor
1refinementX-PLOR_NIH2.23Schwieters, Kuszewski, Tjandra and Clore
2structure solutionX-PLOR_NIH2.23Schwieters, Kuszewski, Tjandra and Clore
3collectionxwinnmr3.6Bruker Biospin
4refinementNAMD2.7bPhillips,Braun,Wang,Gumbart ,Tajkhorshid , Villa ,Chipot ,Skeel, Kale , Schulten
5chemical shift assignmentPIPATHAsbury, Quine,Achuthan, Hu, Chapman, Bertram, Cross