The dynamics of the backbone and side-chains of protein are routinely studied by interpreting experimentally determined 15N spin relaxation rates. R1(15N), the longitudinal relaxation rate, reports on fast motions and encodes, together with the transverse relaxation R2, structural information about the shape of the molecule and the orientation of the amide bond vectors in the internal diffusion frame. Determining error-free 15N longitudinal relaxation rates remains a challenge for small, disordered, and medium-sized proteins. Here, we show that mono-exponential fitting is sufficient, with no statistical preference for bi-exponential fitting up to 800 MHz. A detailed comparison of the TROSY and HSQC techniques at medium and high fields showed no statistically significant differences. The least error-prone DD/CSA interference removal technique is the selective inversion of amide signals while avoiding water resonance. The exchange of amide with solvent deuterons appears to affect the rate R1 of solvent-exposed amides in all fields tested and in each DD/CSA interference removal technique in a statistically significant manner. In summary, the most accurate R1(15N) rates in proteins are achieved by selective amide inversion, without the addition of D2O. Importantly, at high magnetic fields stronger than 800 MHz, when non-mono-exponential decay is involved, it is advisable to consider elimination of the shortest delays (typically up to 0.32 s) or bi-exponential fitting.

Vladlena Kharchenko

Samah Al-Harthi

Andrzej Ejchart

Łukasz Jaremko

Journal of Biomolecular NMR

JOURNAL OF BIOMOLECULAR NMR 为发表关于核磁共振波谱技术发展和创新应用的研究提供了一个论坛，用于研究溶液、液晶、固体和混合环境中生物聚合物的结构和动态特性，例如附着在膜上。这可能包括：通过 NMR 对生物大分子（多肽/蛋白质、DNA、RNA、寡糖）进行三维结构测定。用于研究生物大分子的新 NMR 技术。计算机辅助自动分析多维 NMR 光谱的新方法。计算方法用于核磁共振数据的结构解释，包括结构细化。核磁共振确定的结构与其他方法获得的结构的比较，例如通过蛋白质单晶衍射技术。用于核磁共振实验的样品制备新技术（同位素标记的生物合成和化学方法，生物合成同位素标记的营养物质制备等）。必须包括产品的 NMR 表征。

The Journal of Biomolecular NMR provides an important forum for the publication of research on the development and innovative applications of nuclear magnetic resonance (NMR) spectroscopy. It focuses on the study of the structural and dynamic properties of biopolymers in solution, liquid crystal, solid, and mixed environments, including those attached to membranes. The journal may include topics such as: three-dimensional structure determination of biomacromolecules (peptides/proteins, DNA, RNA, oligosaccharides) using NMR; new NMR techniques for studying biomacromolecules; computer-assisted automated analysis methods for multidimensional NMR spectra; computational methods for structural interpretation of NMR data, including structure refinement; comparisons of structures determined by NMR with those obtained through other methods, such as protein single-crystal diffraction; and new techniques for sample preparation for NMR experiments (including isotopically labeled biosynthesis and chemical methods, and preparation of isotopically labeled nutrients through biosynthesis). All research findings must include NMR characterization of the products.

《Journal of Biomolecular NMR》为研究核磁共振波谱技术的发展与创新应用提供了一个重要的论坛，专注于生物聚合物在溶液、液晶、固体及混合环境中的结构与动态特性研究，例如膜上附着的生物聚合物。该期刊的内容可能包括：利用核磁共振（NMR）对生物大分子（如多肽/蛋白质、DNA、RNA、寡糖）进行三维结构测定；新型NMR技术在生物大分子研究中的应用；计算机辅助的多维NMR光谱自动分析新方法；用于核磁共振数据结构解释的计算方法，包括结构细化；通过蛋白质单晶衍射技术获得的结构与NMR确定的结构的比较；以及用于核磁共振实验的样品制备新技术（如同位素标记的生物合成和化学方法，生物合成同位素标记的营养物质制备等）。所有研究成果必须包括产品的NMR表征。

Category	Quartile
生物学	3
生物学, 光谱学	2
生物学, 生化与分子生物学	3

Pitfalls in measurements of R1 relaxation rates of protein backbone 15N nuclei

ivySCI AI Smartly Parses PDF, Answers Researchers' Questions, and Helps You Understand Papers in Seconds

Journal Info