In vivo effects of metal ions on conformation and mechanical performance of silkworm silks
Abstract Background The mechanism of silk fiber formation is of particular interest. Although in vitro evidence has shown that metal ions affect conformational transitions of silks, the in vivo effects of metal ions on silk conformations and mechanical performance are still unclear. Methods This study explored the effects of metal ions on silk conformations and mechanical properties of silk fibers by adding K + and Cu 2+ into the silk fibroin solutions or injecting them into the silkworms. Aimed by CD analysis, FTIR analysis, and mechanical testing, the conformational and mechanical changes of the silks were estimated. By using BION Web Server, the interactions of K + and N-terminal of silk fibroin were also simulated. Results We presented that K + and Cu 2+ induced the conformational transitions of silk fibroin by forming β-sheet structures. Moreover, the mechanical parameters of silk fibers, such as strength, toughness and Young's modulus, were also improved after K + or Cu 2+ injection. Using BION Web Server, we found that potassium ions may have strong electrostatic interactions with the negatively charged residues. Conclusion We suggest that K + and Cu 2+ play crucial roles in the conformation and mechanical performances of silks and they are involved in the silk fiber formation in vivo. General significance Our results are helpful for clarifying the mechanism of silk fiber formation, and provide insights for modifying the mechanical properties of silk fibers. Highlights Metal ions are essential for silk fiber formation in silkworm. K + and Cu 2+ participate in fiber formation by forming β-sheet structures in silks. K + and Cu 2+ can be used for improving the silk fibers mechanical properties. Graphical abstract [DISPLAY OMISSION]
유료 다운로드의 경우 해당 사이트의 정책에 따라 신규 회원가입, 로그인, 유료 구매 등이 필요할 수 있습니다. 해당 사이트에서 발생하는 귀하의 모든 정보활동은 NDSL의 서비스 정책과 무관합니다.
NDSL에서는 해당 원문을 복사서비스하고 있습니다. 위의 원문복사신청 또는 장바구니 담기를 통하여 원문복사서비스 이용이 가능합니다.
- 이 논문과 함께 출판된 논문 + 더보기