Wang Songlin, Ravula Thirupathi, Stringer John A, Gor'kov Peter L, Warmuth Owen A, Williams Christopher G, Thome Alex F, Mueller Leonard J, Rienstra Chad M
National Magnetic Resonance Facility at Madison (NMRFAM), University of Wisconsin-Madison, Madison, WI, USA.
Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, USA.
Sci Adv. 2025 Jul 25;11(30):eadx6016. doi: 10.1126/sciadv.adx6016. Epub 2025 Jul 23.
Nuclear magnetic resonance (NMR) spectroscopy is a powerful technique with broad impact across the physical and life sciences, and ultrahigh field (UHF), gigahertz-class NMR spectrometers offer exceptional performance, including superior resolution and sensitivity. In solid-state NMR (SSNMR), resolution is primarily constrained by instrumentation rather than molecular tumbling, making it well suited for studying large and complex systems. To fully leverage UHF magnets for SSNMR, it is essential to eliminate line broadening arising from magnetic field drift and couplings among the nuclear spins. We address these challenges using external H lock to compensate for the field drift and long-observation-window band-selective homonuclear decoupling to suppress C homonuclear couplings. We achieve better than 0.2-parts per million resolution in proteins up to 144 kilodalton, enabling unique site resolution for more than 500 amide backbone pairs in two-dimensional experiments. This exceeds the resolution available from solution NMR for large biological molecules, greatly expanding the potential of gigahertz-class NMR for research in life sciences.
核磁共振（NMR）光谱学是一项强大的技术，在物理和生命科学领域有着广泛影响，而超高场（UHF）、千兆赫兹级的NMR光谱仪具有卓越的性能，包括超高的分辨率和灵敏度。在固态NMR（SSNMR）中，分辨率主要受仪器限制而非分子翻滚的影响，这使其非常适合研究大型复杂系统。为了在SSNMR中充分利用UHF磁体，消除由磁场漂移和核自旋间耦合引起的谱线展宽至关重要。我们通过外部氢锁来补偿磁场漂移，并采用长观测窗口带选择性同核去耦来抑制碳同核耦合，从而应对这些挑战。我们在分子量高达144千道尔顿的蛋白质中实现了优于百万分之0.2的分辨率，在二维实验中为500多个酰胺主链对提供了独特的位点分辨率。这超过了溶液NMR对大型生物分子所能达到的分辨率，极大地拓展了千兆赫兹级NMR在生命科学研究中的潜力。
