Graduate School of Science and Engineering, Kinki University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan.
Biopolymers. 2011;96(2):222-7. doi: 10.1002/bip.21402.
Dragline silk is a high-performance biopolymer with exceptional mechanical properties. Artificial spider dragline silk is currently prepared by a recombinant technique or chemical synthesis. However, the recombinant process is costly and large-sized synthetic peptides are needed for fiber formation. In addition, the silk fibers that are produced are much weaker than a fiber derived from a native spider. In this study, a small peptide was chemically synthesized and examined for its ability to participate in fiber formation. A short synthetic peptide derived from Nephila clavata was prepared by a solid-phase peptide method, based on a prediction using the hydrophobic parameter of each individual amino acid residue. After purification of the spider peptide, fiber formation was examined under several conditions. Fiber formation proceeded in the acidic pH range, and larger fibers were produced when organic solvents such as trifluoroethanol and acetonitrile were used at an acidic pH. Circular dichroism measurements of the spider peptide indicate that the peptide has a beta-sheet structure and that the formation of a beta-sheet structure is required for the spider peptide to undergo fiber formation.
牵引丝是一种具有优异机械性能的高性能生物聚合物。人工蜘蛛牵引丝目前是通过重组技术或化学合成制备的。然而，重组过程成本高昂，且纤维形成需要大尺寸的合成肽。此外，所生产的丝纤维比源自天然蜘蛛的纤维弱得多。在这项研究中，合成了一种小肽并研究了其参与纤维形成的能力。基于对每个氨基酸残基疏水性参数的预测，使用固相肽法合成了源自 Nephila clavata 的短合成肽。在对蜘蛛肽进行纯化后，在几种条件下检查了纤维形成情况。在酸性 pH 值范围内可以进行纤维形成，并且在酸性 pH 值下使用三氟乙醇和乙腈等有机溶剂时，会产生更大的纤维。对蜘蛛肽的圆二色性测量表明，该肽具有β-折叠结构，并且β-折叠结构的形成是蜘蛛肽进行纤维形成所必需的。
