Department of Materials Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
Department of Crystalline Materials Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
Int J Mol Sci. 2019 Dec 12;20(24):6262. doi: 10.3390/ijms20246262.
Elastin-like polypeptides (ELPs) are promising candidates for fabricating tissue-engineering scaffolds that mimic the extracellular environment of elastic tissues. We have developed a "double-hydrophobic" block ELP, , inspired by non-uniform distribution of two different hydrophobic domains in natural elastin. has a block sequence of (VGGVG)-(VPGXG)-(VGGVG) that self-assembles to form nanofibers in water. Functional derivatives of with appended amino acid motifs can also form nanofibers, a display of the block sequence's robust self-assembling properties. However, how the block length affects fiber formation has never been clarified. This study focuses on the synthesis and characterization of a novel ELP, , in which the central sequence (VPGVG) is repeated twice by a short linker sequence. The self-assembly behavior and the resultant nanostructures of and were when compared through circular dichroism spectroscopy, atomic force microscopy, and transmission electron microscopy. Dynamic rheology measurements revealed that the nanofiber dispersions of both and at an extremely low concentration (0.034 wt%) exhibited solid-like behavior with storage modulus G' > loss modulus G" over wide range of angular frequencies, which was most probably due to the high aspect ratio of the nanofibers that leads to the flocculation of nanofibers in the dispersion.
弹性蛋白样多肽 (ELPs) 是一种很有前途的组织工程支架构建材料，因为它们可以模拟弹性组织的细胞外环境。我们受天然弹性蛋白中两种不同疏水区不均匀分布的启发，开发了一种“双重疏水性”嵌段 ELP 。 具有 (VGGVG)-(VPGXG)-(VGGVG) 的嵌段序列，在水中自组装形成纳米纤维。 带有附加氨基酸序列的 的功能衍生物也可以形成纳米纤维，这显示了嵌段序列强大的自组装特性。然而，嵌段长度如何影响纤维形成从未被阐明。本研究专注于一种新型 ELP 的合成与表征，其中中央序列 (VPGVG) 由短连接序列重复两次。通过圆二色性光谱、原子力显微镜和透射电子显微镜比较了 和 的自组装行为和所得纳米结构。动态流变学测量表明，两种 的纳米纤维分散体（浓度极低，0.034wt%）在很宽的角频率范围内表现出固态行为，储能模量 G' > 损耗模量 G"，这很可能是由于纳米纤维的高纵横比导致纳米纤维在分散体中絮凝所致。
