NH NH VECTOR CORRELATION IN PEPTIDES BY SOLID STATE NMR

通过固态 NMR 分析肽中 NH NH 向量的相关性

• 批准号: 6355136
• 负责人: BERND REIF
• 金额: $ 2.84万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-05-01 至 2001-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6355136
• 关键词: biological products; biomedical equipment development; biomedical resource; enzymes; technology /technique

We present a novel solid-state NMR pulse sequence to measure the NHi-NHi,, projection angle in peptides under magic angle spinning (MAS). The method is applied to the uniformly 15 N-labelled tripeptide N-Formyl-MLF. The measured angle is directly related to the backbone angles 0 and W. The same experiment can be used to restrain side chain torsion angles, e.g. in "N-labelled arginine. In larger spin systems, the projection angle permits the determination of the geometry between different secondary structure elements. The method relies on the recoupling of the NH dipolar coupling, which is correlated to the nearest neighbor using proton mediated spin diffusion. The heteronuclear interaction is recoupled using the new heteronuclear recoupling scheme T-MREV. In contrast to the conventional MREV-8, the heteronuclear dipolar interaction is not refocussed after each rotor period. This extends the dynamic range of the experiment and allows for a more accurated determinatio n of the r ecoupled interaction. Furthermore, we present here an approach to interpret the dephasing data in a quasi-analytical fashion that permits efficient extraction of molecular parameters. Knowledge of the scaling factor of the sequence is not necessary for the theoretical description of the data.

我们提出了一种新的固态核磁共振脉冲序列来测量