In vitro studies on the structure and properties of silk fibroin aqueous solutions in silkworm

• Published in: International journal of biological macromolecules Vol. 62; pp. 162 - 166
• Main Authors: Jin, Yuan, Hang, Yichun, Luo, Jie, Zhang, Yaopeng, Shao, Huili, Hu, Xuechao
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.11.2013
• Subjects: Aggregates; Animals; aqueous solutions; Biomimetics; Birefringence; Bombyx; Conformation; crystal structure; fibroins; Fibroins - chemistry; Fibroins - metabolism; in vitro studies; light scattering; liquid crystals; Protein Aggregates; Protein Conformation; Rheology; rheometers; silk; Silk fibroin; silk glands; silkworms; Solutions; spinning; Water - chemistry; Birefringence; Silk fibroin; Aggregates; Rheology; Conformation
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2013.08.027

The spinning process of silkworm in vivo attracts great attentions. In this work, the structures and properties of the silk fibroin (SF) aqueous solutions from different divisions of silk glands of silkworms were investigated by using polarized microscope, rotational rheometer, Raman spectrometer and dynamic laser light scattering instrument. It was found that only the anterior (A) division and the anterior part of middle division (MA) of silk gland showed birefringence. With flowing from the posterior part (MP) to the MA part in the middle division of silk gland, the SF aqueous solutions was gradually transformed from random coil/α-helix to β-sheet conformation. Meantime, the elastic and viscous nature of the SF aqueous solution changed, and the mean diameter of SF aggregates increased from 118nm to 331nm. It could be concluded that the structures and properties of the SF aqueous solutions were gradually changed along the silk gland and the liquid crystal structure was initially formed in the MA part of silk gland.