3D DUMAS: Simultaneous acquisition of three-dimensional magic angle spinning solid-state NMR experiments of proteins
July 2012
Publication year: 2012
Source:Journal of Magnetic Resonance, Volume 220
Using the DUMAS (Dual acquisition Magic Angle Spinning) solid-state NMR approach, we created new pulse schemes that enable the simultaneous acquisition of three dimensional (3D) experiments on uniformly 13C, 15N labeled proteins. These new experiments exploit the simultaneous cross-polarization (SIM-CP) from 1H to 13C and 15N to acquire two 3D experiments simultaneously. This is made possible by bidirectional polarization transfer between 13C and 15N and the long living 15N z-polarization in solid state NMR. To demonstrate the power of this approach, four 3D pulse sequences (NCACX, CANCO, NCOCX, CON(CA)CX) are combined into two pulse sequences (3D DUMAS–NCACX–CANCO, 3D DUMAS–NCOCX–CON(CA)CX) that allow simultaneous acquisition of these experiments, reducing the experimental time by approximately half. Importantly, the 3D DUMAS–NCACX–CANCO experiment alone makes it possible to obtain the majority of the backbone sequential resonance assignments for microcrystalline U–13C,15N ubiquitin. The DUMAS approach is general and applicable to many 3D experiments, nearly doubling the performance of NMR spectrometers.
Graphical abstract
Highlights
? DUMAS enables the simultaneous acquisition of two 3D spectra of proteins. ? DUMAS nearly doubles the performance of NMR spectrometers. ? 3D DUMAS–NCACX–CANCO enables 75% of backbone assignment of ubiquitin.
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