Molecular Dynamics Calculation on the Generation of Aggregated Structure of Poly(L-Alanine) from the Aqueous Solution

作者：Aoki Akihiro^*; Yamasaki Shizuo; Horiguchi Kumiko; Kametani Syunsuke; Asakura Tetsuo

来源：Kobunshi Ronbunshu, 2010, 67(1): 45-50.

DOI：10.1295/koron.67.45

• Poly(L-Alanine)
• Molecular Dynamics
• Molecular Mechanics
• Aggregation

Silk fibroins from wild silkworms such as A. pernyi, S. c. ricini and A. yamamai consist of poly (L-alanine) (PLA) and Gly rich regions. The PLA chains form a crystalline region, which is the origin of the high strength of these silk fibers. Molecular dynamics calculations were performed to study the aggregation mechanism of 100 extended PLA chains during a water elimination process from aqueous solution. The aggregation occurs in a step-wise manner. Namely, the formation of inter-molecular hydrogen bonds among more than three PLA chains occurs rapidly after the formation of a sufficient number of inter-molecular hydrogen bonds between two PLA chains. The averaged torsion angles of Ala residues during the dimer formation process do not change significantly, but the distribution of the angles is very large. Then a remarkable change in the torsion angles occur at the stage of inter-molecular hydrogen bond formation among more than three PLA chains.

• 出版日期2010-1