Institute of Biological Sciences and Biotechnology, Donghua University, Shanghai 201620, China.
Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, Uppsala, Sweden; Department of Neurobiology, Care Sciences and Society, Karolinska Institute, Neo, 141 86 Huddinge, Sweden.
Int J Biol Macromol. 2020 Jul 1;154:765-772. doi: 10.1016/j.ijbiomac.2020.03.042. Epub 2020 Mar 10.
Spiders can spin seven different types of silk, some of which are well characterized, but studies on natural and synthetic pyriform silks are few. In this study, recombinant spidroins composed of one to three pyriform repeat units from Araneus ventricosus, in some cases flanked with non-repetitive N- and C-terminal domains (NT and CT), were produced and spun into continuous silk fibers using a wet-spinning process in organic solvents. All the fibers showed high and similar tensile strain (60-80%), but the Young's modulus, stress and toughness of fibers increased with increasing number of repeat units and in the presence of NT and CT as well. Systematic studies of the secondary structure contents of the different spinning dopes and spun fibers revealed no major differences between the different types of recombinant spidroins. This suggests that optimal tensile properties of artificial spider silks require the presence of several repetitive units as well as terminal domains and that secondary structure content of silk dope and fibers have limited correlation with mechanical behaviors.
蜘蛛可以纺出七种不同类型的丝，其中一些已经得到了很好的描述，但对天然和合成梨形丝的研究却很少。在这项研究中，我们使用有机溶剂的湿法纺丝工艺，从瘤胸长足蛛（Araneus ventricosus）中生产出由一个到三个梨形重复单元组成的重组蜘蛛丝蛋白，并将其纺成连续的丝纤维。所有纤维都表现出高且相似的拉伸应变（60-80%），但纤维的杨氏模量、应力和韧性随着重复单元数量的增加以及 NT 和 CT 的存在而增加。对不同纺丝原丝和纺制纤维的二级结构含量的系统研究表明，不同类型的重组蜘蛛丝蛋白之间没有明显差异。这表明，人工蜘蛛丝的最佳拉伸性能需要存在几个重复单元以及末端结构域，并且丝原丝和纤维的二级结构含量与机械性能相关性有限。
