Functionalization of Silkworm Silk

Constructing novel functional silkworm silks for various applications has captured increasing attention over the past decade [45, 46]. 

---

FIGURE 24.4 Silkworm genetic loci responsible for carotenoid transport, (a) List of the genetic loci. + indicates a recessive allele of I. (b) Schematic illustration of the function of the F, I, and C genes. Only larvae with the genotype Y + C] transport carotenoids into the silk gland and create yellow cocoons. 

Not all of the fibroin protein is in / -sheets. As the amino acid composition in Figure 6.12 shows, fibroin contains small amounts of other, bulky amino acids like valine and tyrosine, which would not fit into the structure shown. These are carried in compact folded regions that periodically interrupt the sheet segments, and they probably account for the amount of stretchiness that silk fibers have. In fact, different species of silkworms produce fibroins with different extents of such non - / -sheet structure and corresponding differences in elasticity. The overall fibroin structure is a beautiful example of a protein molecule that has evolved to perform a particular function — to provide a tough, yet flexible fiber for the silkworm s cocoon or the spider s web. 

The structure of silk fibroin from a wild silkworm was examined by using solution and solid state NMR methods. The structural transition of the silk fibroin in aqueous solution was monitored by using solution NMR spectroscopy as a function of temperature. The torsion angles of several Ala and Gly residues in the model peptide, GGAGGGYGGDGG(A)i2GGA-GDGY-GAG, were determined by the conformation-dependent chemical shifts, REDOR and 2D spin-diffusion techniques in the solid state. 

Functionalization of Colored/Fluorescent Silkworm Silk Fibrous Materials... 

In order to functionalize silk fibers without disturbing their performance, the structure of silk fibers needs to be understood. Although the Bombyx mori silkworm silk structure has been investigated for some time, the hierarchical structure did... 

---