Fig. 5.

Correlation test of Pearson between amino acid composition and mechanical properties (mechanical resistance and elasticity) of spider silks (A.diadematus and N.clavipes). A correlation test was performed between the composition in amino acids of silk issued from aciniform, cylindriform, flagelliform, ampullate major and ampullate minor glands (Andersen 1970), and the ultimate tensile strength or strain at break for these different silks (Vollrath and Porter 2006). A positive value indicates a correlation between the proportion of the amino acid and the mechanical property, a negative value suggests a correlation between the proportion of the amino acid and the other property (deleterious effect of the amino acid on the considered mechanical characteristic). Legends for the amino acids in order of mention: alanine, glycine, serine, proline, aspartic acid, glutamic acid, tyrosine, threonine, phenylalanine, valine, leucine, isoleucine, histidine, lysine, arginine