Becker Nathan, Oroudjev Emin, Mutz Stephanie, Cleveland Jason P, Hansma Paul K, Hayashi Cheryl Y, Makarov Dmitrii E, Hansma Helen G
Department of Physics, University of California, Santa Barbara, California 93106, USA.
Nat Mater. 2003 Apr;2(4):278-83. doi: 10.1038/nmat858.
Spider capture silk is a natural material that outperforms almost any synthetic material in its combination of strength and elasticity. The structure of this remarkable material is still largely unknown, because spider-silk proteins have not been crystallized. Capture silk is the sticky spiral in the webs of orb-weaving spiders. Here we are investigating specifically the capture spiral threads from Araneus, an ecribellate orb-weaving spider. The major protein of these threads is flagelliform protein, a variety of silk fibroin. We present models for molecular and supramolecular structures of flagelliform protein, derived from amino acid sequences, force spectroscopy (molecular pulling) and stretching of bulk capture web. Pulling on molecules in capture-silk fibres from Araneus has revealed rupture peaks due to sacrificial bonds, characteristic of other self-healing biomaterials. The overall force changes are exponential for both capture-silk molecules and intact strands of capture silk.
蜘蛛的捕丝是一种天然材料，在强度和弹性的结合方面几乎优于任何合成材料。这种非凡材料的结构在很大程度上仍然未知，因为蜘蛛丝蛋白尚未结晶。捕丝是圆蛛蛛网中的粘性螺旋丝。在这里，我们专门研究来自园蛛属（一种无筛器圆蛛）的捕获螺旋丝。这些丝的主要蛋白质是鞭毛状蛋白，一种丝心蛋白变体。我们提出了鞭毛状蛋白的分子和超分子结构模型，这些模型源自氨基酸序列、力谱学（分子拉伸）以及对整块捕网的拉伸。对园蛛属捕丝纤维中的分子进行拉伸，揭示了由于牺牲键导致的断裂峰，这是其他自愈生物材料的特征。捕丝分子和完整的捕丝束的总力变化都是指数性的。
