Unidirectional coherence transfer is highly efficient in intrinsically disordered proteins (IDPs). Their elevated ps-ns timescale dynamics ensures long transverse (T₂) relaxation times allowing sophisticated coherence transfer pathway selection in comparison to folded proteins. ¹H^α-detection ensures non-susceptibility to chemical exchange with the solvent and enables chemical shift assignment of consecutive proline residues, typically abundant in IDPs. However, many IDPs undergo a disorder-to-order transition upon interaction with their target protein, which leads to the loss of the favorable relaxation properties. Long coherence transfer routes now result in prohibitively large decrease in sensitivity. We introduce a novel 4D ¹H^α-detected experiment HACANCOi, together with its 3D implementation, which warrant high sensitivity for the assignment of proline-rich regions in IDPs in complex with a globular protein. The experiment correlates ¹H^α_i, ¹³C^α_i, ¹⁵N_i and \(^{13} C^{\prime}_{i}\) spins by transferring the magnetization concomitantly from ¹³C^α_i to ¹⁵N_i and \(^{13} C^{\prime}_{i}\). The B1 domain of protein G (GB1), and the enteropathogenic E. coli EspF in complex with human SNX9 SH3, serve as model systems to demonstrate the attainable sensitivity and successful sequential assignment.

单向相干转移在本质上无序的蛋白质 (IDP) 中非常有效。与折叠蛋白质相比，它们提高的 ps-ns 时间尺度动力学确保了较长的横向 (T ₂ ) 弛豫时间，允许复杂的相干转移途径选择。¹ H ^α检测确保对与溶剂的化学交换不敏感，并能够对连续脯氨酸残基进行化学位移分配，通常在 IDP 中含量丰富。然而，许多 IDP 在与其靶蛋白相互作用时经历了无序到有序的转变，这导致了有利的松弛特性的丧失。长的相干传输路径现在会导致灵敏度大幅下降。我们介绍了一种新颖的 4D ¹ H^α-检测实验 HACANCOi 及其 3D 实施，保证了 IDP 中富含脯氨酸区域与球状蛋白复合物的分配具有高灵敏度。该实验通过将磁化从¹³ C ^α _i伴随转移到¹⁵ N _i来关联¹ H ^α _i、¹³ C ^α _i、¹⁵ N _i和\(^{13} C^{\prime}_{i}\)自旋和\(^{13} C^{\prime}_{i}\)。蛋白的B1域G（GB1）和肠致病性大肠杆菌大肠杆菌 EspF 与人类 SNX9 SH3 复合，作为模型系统来证明可达到的灵敏度和成功的顺序分配。