Hsieh Shu-Ju Micky, Mallam Anna L, Jackson Sophie E, Hsu Shang-Te Danny
Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan.
Biomol NMR Assign. 2014 Oct;8(2):439-42. doi: 10.1007/s12104-013-9510-6. Epub 2013 Jul 14.
YibK is a tRNA methyltransferase from Haemophilus influenzae, which forms a stable homodimer in solution and contains a deep trefoil 31 knot encompassing the C-terminal helix that threads through a long loop. It has been a model system for investigating knotted protein folding pathways. Recent data have shown that the polypeptide chain of YibK remains loosely knotted under highly denaturing conditions. Here, we report (1)H, (13)C and (15)N chemical shift assignments for YibK and its variant in the presence of 8 M urea. This work forms the basis for further analysis using NMR techniques such as paramagnetic relaxation enhancement, residual dipolar couplings and spin-relaxation dynamics analysis.
YibK是一种来自流感嗜血杆菌的tRNA甲基转移酶，它在溶液中形成稳定的同型二聚体，并且包含一个深三叶结，该结围绕着穿过一个长环的C端螺旋。它一直是研究打结蛋白质折叠途径的模型系统。最近的数据表明，在高度变性的条件下，YibK的多肽链仍保持松散的打结状态。在这里，我们报告了在8 M尿素存在下YibK及其变体的（1）H、（13）C和（15）N化学位移归属。这项工作为使用诸如顺磁弛豫增强、剩余偶极耦合和自旋弛豫动力学分析等核磁共振技术进行进一步分析奠定了基础。
