Copper in the silk formation process of Bombyx mori silkworm.
Evidence is presented here that cupric ions play a part in the natural spinning of Bombyx mori silk. Proton induced X-ray emission studies revealed that the copper content increased from the posterior part to the anterior part of silk gland, and then further increased in the silk fiber. Spectrophotometric analysis demonstrated that cupric ions formed coordination complexes with silk fibroin chains while Raman spectroscopy indicated that they induced a conformation transition from random coil/helix to beta-sheet. Taken together these findings indicate that copper could play a role in the natural spinning process in silkworms.
Zhou
Li
L
Department of Macromolecular Science, The Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai 200433, PR China.
Chen
Xin
X
Shao
Zhengzhong
Z
Zhou
Ping
P
Knight
David P
DP
Vollrath
Fritz
F
D000818:Animals; D012831:Bombyx / Q000033:anatomy & histology / Q000378:metabolism*; D003300:Copper / Q000032:analysis / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D005349:Fibroins / Q000737:chemistry / Q000378:metabolism; D019476:Insect Proteins / Q000096:biosynthesis* / Q000737:chemistry; D009499:Neutral Red / Q000737:chemistry / Q000378:metabolism; D017433:Protein Structure, Secondary; D047011:Silk; D013052:Spectrometry, X-Ray Emission; D013059:Spectrum Analysis, Raman
D019476:Insect Proteins; D047011:Silk; D009499:Neutral Red; D003300:Copper; D005349:Fibroins