Determination of methyl order parameters using solid state NMR under off magic angle spinning
- 60 Downloads
Quantification of dipolar couplings in biological solids is important for the understanding of dynamic processes. Under Magic Angle Spinning (MAS), order parameters are normally obtained by recoupling of anisotropic interactions involving the application of radio frequency pulses. We have recently shown that amide backbone order parameters can be estimated accurately in a spin-echo experiment in case the rotor spinning angle is slightly mis-calibrated. In this work, we apply this method to determine methyl order parameters in a deuterated sample of the SH3 domain of chicken α-spectrin in which the methyl containing side chains valine and leucine are selectively protonated.
KeywordsSolid-state NMR Off magic angle spinning Spin Echo Microcrystalline proteins Perdeuteration
This work was performed in the framework of the SFB-1035 (Project B07; German Research Foundation, DFG). We acknowledge support from the Helmholtz-Gemeinschaft and the Deutsche Forschungsgemeinschaft (Grants Re1435). We are grateful to the Center for Integrated Protein Science Munich (CIPS-M) for financial support. We thank Dr. Sam Asami for stimulating discussions, and making the methyl REDOR order parameters for α-spectrin SH3 available for this study.