NOVEL STRATEGIES FOR BACKBONE & SIDECHAIN ASSIGNMENT IN SOLID PHASE POLYPEPTIDES

异构体和同源体主链和侧链相关性是 对于多重标记肽的NMR分配至关重要， 蛋白质处于固定状态。 相关性通常被检索 从多维（'H，13C'I 'N）相关实验。 我们 证明，或者，少量的一维 采用选择性和有效的异质结的实验 偏振转移可用于骨干分配。 我们也 展示了如何将这种方法扩展到侧链分配， 通过键、通过间隔或质子介导转移均聚物 技术. 特别地，我们研究了偏振传输 动力学（NH，Cal Cp）三肽的子系统，并比较我们的 多自旋系统的理论预测结果。 这些 可以在任意MAS频率下采用实验方案 并且对于所施加的R的大小是非常宽容的。F. 领域的

Hetero- and homonuclear backbone and sidechain correlations are essential for NMR assignments in multiply labeled peptides and proteins in the immobilized state. Correlations are usually retrieved from multi-dimensional ('H, 13C'I 'N) correlation experiments. We demonstrate that, alternatively, a small number of one-dimensional experiments employing selective and efficient heteronuclear polarization transfer can be used for backbone assignments. We also show how this approach can be extended for sidechain assignments using homonuclear through-bond, through space or proton-mediated transfer techniques. In particular, we investigate the polarization transfer dynamics in (NH, Cal Cp) subsystems of a tripeptide and compare our results to theoretical predictions in multi-spin systems. These experimental protocols can be employed at arbitrary MAS frequencies and are very forgiving with respect to the size of the applied r. f. fields.