Sructural study of the M4 Immune Evasion Protein

溶液NMR是一个强大的工具，用于蛋白质和蛋白质复合物的结构表征不超过200-300个氨基酸残基，但在获得大量的正确重折叠，同位素富集的蛋白质的困难，使这种方法具有挑战性的m4蛋白。 然而，我们已经能够获得几乎完整的骨架共振分配，以及有限的酰胺-酰胺NOE数据，该系统。在建模技术的最新进展，原则上使用程序罗塞塔，使人们有可能模拟的基础上，这种化学位移和有限的NOE信息的蛋白质的结构。 Rosetta隐含的物理上真实的能量函数可以区分天然和非天然蛋白质构象，化学位移和NOE信息大大减少了构象空间的允许区域。m4的早期模型已经从这种方法中推导出来，这些模型目前正在接受新开发的验证方法，以评估所获得的结构有多明确。

Solution NMR is a powerful tool for structural characterization of proteins and protein complexes not exceeding 200-300 amino acid residues, but difficulties in obtaining large quantities of properly refolded, isotopically enriched protein make this approach challenging for the m4 protein. However, we have been able to obtain virtually complete backbone resonance assignments as well as limited amide-amide NOE data for this system. Recent advances in modeling techniques using the program Rosetta in principle make it possible to model the structure of the protein on the basis of this chemical shift and limited NOE information. The physically realistic energy function implicit to Rosetta can discriminate native from non-native protein conformations and the chemical shift and NOE information strongly reduce the permissible region of conformational space. Early stage models for m4 have been derived from this approach, and these are currently subjected to newly developed validation methods in order to evaluate how unambiguous the obtained structure is.