Ernst Matthias, Detken Andreas, Böckmann Anja, Meier Beat H
Physical Chemistry, ETH Zurich, CH-8093 Zürich, Switzerland.
J Am Chem Soc. 2003 Dec 24;125(51):15807-10. doi: 10.1021/ja0369966.
Proteins are not always available in amounts desirable for solid-state magic-angle spinning (MAS) nuclear-magnetic resonance (NMR) spectroscopy. To maximize the signal-to-noise ratio achievable with small samples, the filling factor must be optimized by using small-diameter MAS rotors. These rotors have the added benefit of allowing higher radio frequency field amplitudes during polarization transfer steps and during decoupling periods as well as allowing higher spinning frequencies. We demonstrate the advantages of relatively fast MAS (30 kHz using a 2.5 mm rotor) compared to MAS at 12 kHz for the 10.4 kDa model protein Crh with 93 residues and show that the signal-to-noise ratio in two-dimensional correlation spectra can be significantly improved by taking advantage of optimized pulse sequences available with rapid MAS.
蛋白质的量并不总是能满足固态魔角旋转（MAS）核磁共振（NMR）光谱分析的需求。为了使小样品能获得最大的信噪比，必须通过使用小直径的MAS转子来优化填充因子。这些转子还有额外的好处，即在极化转移步骤和解耦期间允许更高的射频场振幅，同时也允许更高的旋转频率。我们展示了对于含有93个残基的10.4 kDa模型蛋白Crh，与12 kHz的MAS相比，相对快速的MAS（使用2.5 mm转子，30 kHz）的优势，并表明利用快速MAS可用的优化脉冲序列，二维相关光谱中的信噪比可以显著提高。
