Table 2. Comparison of silks composed of beta-sheet forming proteins.

	Silkworm	Webspinner	Raspy cricket
Major silk fibroin size (kDa)	390 [39]	∼67 [40]	220, 300
Fibroin composition	46% Gly, 30% Ala, 12% Ser [39]	44% Gly, 31% Ser [41]	19% Ala, 19% Gly, 17% Ser
Repetitive sequence motifs	Yes [39]	Yes [42]	Yes
Dominant protein structure	beta-sheet [42]	beta-sheet [41]	beta-sheet
Role for cysteine cross-links	Yes [43]	Yes [40]	Yes
Silk gland	Labial gland [17]	Dermal glands on tarsi [44]	Labial gland
Spinneret	Rigid tube on labium [45]	Tubular bristles [44]	Movable labium-hypopharynx
Form of mature silk	Double fiber	Multiple fine fibers [41]	Fiber or film