用固体核磁共振和X射线衍射研究了绿猞猁蛛丝的蛋白质二级结构。

PubMed ID
发表日期 2015年Nov月

原始出处 国际生物大分子杂志
International journal of biological macromolecules
作者 Xu  Dian  Shi  Xiangyan  Thompson  Forrest  Weber  Warner S  Mou  Qiushi  Yarger  Jeffery L 

文献标题 用固体核磁共振和X射线衍射研究了绿猞猁蛛丝的蛋白质二级结构。
Protein secondary structure of Green Lynx spider dragline silk investigated by solid-state NMR and X-ray diffraction.

文献摘要

采用X射线衍射和固体核磁共振技术对绿猞猁蜘蛛主要壶腹丝的二级结构进行了表征。通过X射线衍射测量,发现β-片状纳米晶沿纤维轴高度取向,取向顺序为fc≈0.98。纳米晶的平均尺寸为2.5nm×3.3nm×3.8nm。除了明显的纳米晶区外,还观察到fa≈0.89的部分取向非晶区。采用二维(13)C-(13)C空间和键合固体核磁共振实验,研究了绿脓杆菌丝蛋白的结构细节。结果表明,β-片状纳米晶占蛋白质的40.0±1.2%,且以富含丙氨酸的重复基序为主。此外,根据核磁共振数据,18±1%的丙氨酸、60±2%的甘氨酸和54±2%的丝氨酸被并入螺旋构象中。


In this study, the secondary structure of the major ampullate silk from Peucetia viridans (Green Lynx) spiders is characterized by X-ray diffraction and solid-state NMR spectroscopy. From X-ray diffraction measurement, β-sheet nanocrystallites were observed and found to be highly oriented along the fiber axis, with an orientational order, fc≈0.98. The size of the nanocrystallites was determined to be on average 2.5nm×3.3nm×3.8nm. Besides a prominent nanocrystalline region, a partially oriented amorphous region was also observed with an fa≈0.89. Two-dimensional (13)C-(13)C through-space and through-bond solid-state NMR experiments were employed to elucidate structure details of P. viridans silk proteins. It reveals that β-sheet nanocrystallites constitutes 40.0±1.2% of the protein and are dominated by alanine-rich repetitive motifs. Furthermore, based upon the NMR data, 18±1% of alanine, 60±2% glycine and 54±2% serine are incorporated into helical conformations.


获取全文 10.1016/j.ijbiomac.2015.07.048