A team of Swedish, Norwegian and Spanish researchers has presented the three-dimensional structure of a region of the proteins of spider webs, which opens the way to the development of more resistant artificial materials.
Scientists unveil today in the British scientific journalNature thethree-dimensional structure of a region of spidroines, proteins present in the elastic fibers of thespidersEuprosthenops australis. Specifically, it is the domain called N-terminal, responsible for regulating the assembly of the fibers of the material that makes this species of arachnid.Silk proteins accumulate in a gland, the Ampulácea major, located at the end of the abdomen of the spider’s body. As they move through the gland, the long molecules ofspidroin are organized to form a true liquid crystal. A little before reaching the end of the gland,a short distance from the outlet to the outside, they abruptly turn into a solid, insoluble fiber. Until now, it was a mystery how the rapid transition occurred from soluble protein (while it is inside the secretory gland) to insoluble (just before going outside). The regulation that pH changes exert on the N-terminal domain offers a response.
“It is something that nature does, but that man has not been able to build,” said Cristina Casals, a researcher at the Complutense University of Madrid and co-author of the study. The specialist further explained thatspider silk is a biopolymer that is proportionately stronger than steel and can be stretched up to 135 percent of its original lengthwithout breaking. This silk is also three times stronger than the most advanced synthetic fibers known today, and nothing similar has been produced so far.
