Sun Lijuan, Zhao Xiaojun
Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital , Sichuan University, Chengdu 610041, China.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2009 Dec;26(6):1276-80.
Different spider fibroin non crystalline motifs GGAS and GPGGY were inserted into the middle of RADA16-I . The resulting peptides were R1 (n-RADARADAGGASRADARADA-c) and R2 (n-RADARADAGPGGYRADARADA-c). Fourier transform infrared spectrum (FTIR) was used to identify the secondary structure, while atomic force microscopy (AFM) and transmitting electron microscope (TEM) were used to investigate nanofiber formation of the peptides. These results illustrate that R1 and R2 form random coils and self-assemble into short fibrillar nanostructures. R1 and R2 display a noticeable change in the formation of nanofibers with time. They become longer and wider with the increase of beta-sheet content. R1 forms less and longer fibers than R2; the nanofibers formed by R2 have bend. These characteristics provide a close correlation for the roles of amino acid sequence and beta-sheet structure in nanofiber formation.
将不同的蜘蛛丝蛋白非结晶基序GGAS和GPGGY插入到RADA16-I的中间。得到的肽分别为R1（n-RADARADAGGASRADARADA-c）和R2（n-RADARADAGPGGYRADARADA-c）。利用傅里叶变换红外光谱（FTIR）鉴定二级结构，同时使用原子力显微镜（AFM）和透射电子显微镜（TEM）研究肽的纳米纤维形成情况。这些结果表明，R1和R2形成无规卷曲并自组装成短的纤维状纳米结构。R1和R2在纳米纤维形成过程中随时间呈现出明显变化。随着β-折叠含量的增加，它们变得更长更宽。R1形成的纤维比R2少且长；R2形成的纳米纤维有弯曲。这些特性为氨基酸序列和β-折叠结构在纳米纤维形成中的作用提供了紧密关联。
