Spider prey-wrapping silk is an -helical coiled-coil/-sheet hybrid nanofiber

Solid-State NMR results on C-13-Ala/Ser and C-13-Val enriched Argiope argentata prey-wrapping silk show that native, freshly spun aciniform silk nanofibers are dominated by -helical (approximate to 50% total) and random-coil (approximate to 35% total) secondary structures, with minor -sheet nanocrystalline domains (approximate to 15% total). This is the most in-depth study to date characterizing the protein structural conformation of the toughest natural biopolymer: aciniform prey-wrapping silks.