Composition
Silk produced by A. atlas has considerably different composition of amino acids than the common silks as seen from Table 1. Among the major amino acids, A. at- las has more than twice the tyrosine, about 53 % higher alanine but about 50 % lower glycine and 56 % lower serine content than B. mori silk. However, the alanine and glycine content in A. atlas silk is similar to that of the wild silks. The glycine/alanine ratio for A. atlas silk is 0.5, much lower than that of mulberry (1.5) and the common wild silks (0.8). Amount of glycine and alanine determines the crystallographic form of the proteins [12,
13]. The lower ratio glycine/alanine in A. atlas silk sug- gests that A. atlas silk could have a considerably differ- ent crystallographic structure compared to mulberry and wild silks. A. atlas silk has much higher amounts of hydrophobic amino acids (67 %) compared to the hy- drophilic amino acids (23 %) indicating that the A. at- las silk may have lower moisture absorption and lower sorption of dyes and chemicals if the crystal structures and % crystallinity are similar.