Development of Artificial Spider Silk

Stronger than steel, but also five times more elastic than Kevlar. The spider web silk (grossamer), a protein fiber spun by spiders, has for a long time fascinated the scientific world because it's the strongest natural fiber known, and attempts to copy the material for use in service of the human being have been many. Now, researchers at the Swedish University of Agricultural Sciences (SLU) have come a step closer to the solution, according to an article at their website, www.SLU.se.

It is in a new study, published in the British science journal Nature that the new finding is presented. The finding is crucial in the production of spider thread: by lowering their pH, a spider can begin the conversion to silk.

Inside the spider's body, there is a gland of a sticky mass of protein molecules. It is only when it's time for the spider to spin a thread that the protein is pressed through a small channel, and is formed to a thread. Along the channel, it has been detected that the pH is slightly lowered, from pH 7 (neutral) to pH 6, a more acidic level.

The SLU researchers have been able to see how the lower pH is making the sticky mass to a solid thread, namely how the proteins in the mass start to arrange in a different way when the pH drops lower. To put it simply: the researchers have seen what it is the lower pH that stimulates the thread formation in a spider.

In addition, the researchers have managed to copy this process into a case of experiments. They have allowed bacteria with implanted genes from the spider Euprosthenops australis, a species that makes one of the strongest threads, make the spider silk web.

But what are we going to do with the spider thread? According to My Hedhammar, who is one of the researchers behind the new study, the silk could in the future be used to repair for example, burned skin or an Achilles tendon rupture, everything from surgical sutures to bullet-proof vests.

My Hedhammar says that today, there is not really any suitable material to dress wounds or repair the body, but that the spider silk could actually be usable in these purposes because the human body doesn't reject it. She adds that since the spider silk consists of proteins, you can give it additional properties that are similar to parts of the human body. In other words, you can in a way "customize" tissue and therefore, silk can be of great importance in medical technology.

According to My Hedhammar, the new discovery provides better possibilities to control the production of spider web - a requirement for the production to happen on a larger scale. Within five to ten years, Hedhammar believes that the spider thread will start to be used in the human body, the article states.

Swedish University of Agricultural Sciences (SLU), www.SLU.se