原子力显微镜下蚕丝及蜘蛛丝的微观结构

Microstructures of Bombyx mori Silk and Spider Silk Revealed by Atomic Force Microscopy

利用原子力显微镜研究了蚕丝丝素、蜘蛛牵引丝及其内外层包卵丝的微观结构。研究表明 ,丝素和包卵丝纤维的纵向表面都有成丝过程中液态丝蛋白流动而形成的清晰的构槽和条纹 ,在低速下自然分泌的牵引丝的表面皮层相对比较细腻 ,而垂直下落蜘蛛在高速下分泌的牵引丝具有和丝素纤维比较相似的微观结构特征。这些丝纤维的断面内都分布有大量微细的原纤 ,形状基本为圆形 ,其中三种蜘蛛丝的微纤维直径相似 ,而丝素纤维内的微纤维要粗得多。

The microstructures of Bombyx mori fibroin and dragline, egg-case silk fibers of Araneus Ventricosus spider were studied by atomic force microscopy (AFM). The results indicated that there were clear stripes formed by the flow elongation of liquid fibroin during spinning process in the surfaces of fibroin and spider egg-case silk. The natural dragline silk secreted by a spider at low rate had finer structure in its skin surface than fibroin, and the dragline silk secreted by a dropping spider at high rate had similar microstructures with that of fibroin. There were a great number of circular nanofibrils within these samples. The diameters of three kinds of spider silk were similar and smaller than that of Bombyx mori fibroin.