Dragline,framework and cocoon silk fibers of Araneus Ventricosus were used for this study.To investigate the microstructure mechanisms of stress-strain behavior of spider silk,firstly,amino acid compositions were anal...Dragline,framework and cocoon silk fibers of Araneus Ventricosus were used for this study.To investigate the microstructure mechanisms of stress-strain behavior of spider silk,firstly,amino acid compositions were analyzed and molecular conformations and crystallinity were measured with Raman spectra and X-ray diffraction respectively.The results showed that there were more amino acids with large side groups and polar ones in spider silk than those of Bombyx silk,and the amino acid distribution varied with different spider silk.The molecular structures were mainly α-helix and β-sheet,and random coil and β-turn existed as well.The proportions and arrangement of these conformations of dragline silk were different from framework and cocoon silk fibers.Microstructure was one of important factors of excellent mechanical properties of spider silk.Crystallinity of spider silk was very low,which implied that the roles of crystal on spider silk were not as great as other protein fibers.展开更多
The spider dragline silk has excellent mechanical properties. The stress- strain curves of dragline silk fibers have intraspecific and intraindividual variability because of the spider’s active control during spinnin...The spider dragline silk has excellent mechanical properties. The stress- strain curves of dragline silk fibers have intraspecific and intraindividual variability because of the spider’s active control during spinning process. To investigate the relationship between the morphology of dragline silk fibers and spinning conditions, four samples were made at the reeling rates of 1 mm/s, 20 mm/s, 43.5 mm/s and 110 mm/s from the major ampullate glands of Araneus Ventricosus and the other two of dragline silks were prepared from a crawling or dropping spider. The surface microstructure and nanofibril characteristic were analyzed with atomic force microscopy (AFM). AFM images of 2 000 nm *2 000 nm and 500 nm*500 nm of these samples showed that the spinning condition influenced the surface roughness and fibril size, while AFM images of 200 nm*200 nm clearly displayed that dragline silk of Araneus Ventricosus included sheet macro-conformation structure. These results can facilitate the further investigation of the spinning mechanism of a spider in order to understand mechanical properties and macromolecular structures of dragline silk.展开更多
文摘Dragline,framework and cocoon silk fibers of Araneus Ventricosus were used for this study.To investigate the microstructure mechanisms of stress-strain behavior of spider silk,firstly,amino acid compositions were analyzed and molecular conformations and crystallinity were measured with Raman spectra and X-ray diffraction respectively.The results showed that there were more amino acids with large side groups and polar ones in spider silk than those of Bombyx silk,and the amino acid distribution varied with different spider silk.The molecular structures were mainly α-helix and β-sheet,and random coil and β-turn existed as well.The proportions and arrangement of these conformations of dragline silk were different from framework and cocoon silk fibers.Microstructure was one of important factors of excellent mechanical properties of spider silk.Crystallinity of spider silk was very low,which implied that the roles of crystal on spider silk were not as great as other protein fibers.
基金science and technology office of Jiangsu province
文摘The spider dragline silk has excellent mechanical properties. The stress- strain curves of dragline silk fibers have intraspecific and intraindividual variability because of the spider’s active control during spinning process. To investigate the relationship between the morphology of dragline silk fibers and spinning conditions, four samples were made at the reeling rates of 1 mm/s, 20 mm/s, 43.5 mm/s and 110 mm/s from the major ampullate glands of Araneus Ventricosus and the other two of dragline silks were prepared from a crawling or dropping spider. The surface microstructure and nanofibril characteristic were analyzed with atomic force microscopy (AFM). AFM images of 2 000 nm *2 000 nm and 500 nm*500 nm of these samples showed that the spinning condition influenced the surface roughness and fibril size, while AFM images of 200 nm*200 nm clearly displayed that dragline silk of Araneus Ventricosus included sheet macro-conformation structure. These results can facilitate the further investigation of the spinning mechanism of a spider in order to understand mechanical properties and macromolecular structures of dragline silk.