As the co-author of the article explained to STA and a researcher at the Jovan Hadji ZRC SAZU Matjaz Gregoric Biological Institute, spiders have several types of silk, and the material properties of silk vary widely between different types of spiders.
In a study published in the journal Communications Biology, researchers focused on a species of Darwin's tree spider, under the scientific name Caerostris darwini. She is known for building the largest known networks she introduces to the unique spider habitat, and they are built from the strongest silk, which, according to Gregoric, is "an absolute record for tight force" or "the amount of energy, that we need to tear. fiber ".
It's called silk, which is called "major ampullate" in English, or MA silk, and the thread that spiders build with this type of silk is called a drawing thread. This type of silk is the highest quality biological material in terms of tensile strength and is superior to many synthetic materials.
The main purpose of the research of Swedish and American researchers was, therefore, to find out what might have caused this unusually high quality web in the aforementioned species of spiders. The researchers predict that the response lies in new or different proteins that contribute to the higher tensile strength of their silk.
According to Gregoric, spider silk is composed primarily of proteins. However, MA silk is mainly composed of two proteins called MaSp1 and MaSp2, and researchers have found that Darwin's spider silk is also composed of a third protein, called MaSp4a. This new protein has regions that are thought to contribute to the greater elasticity of spider silk.
In addition, the researchers found that the silk glands of this type clearly differ from all others known so far. "Silk is created in the glands of the feces as a liquid yarn, and is transformed into a solid state driven by the derivative. The peculiarities of glandular derivatives, such as their morphology and changes in pH, are also likely to contribute to the final material properties of silk. we assume that the unique structure of the glandular derivatives of Darwin's tree is also linked to their extraordinary quality silk, "said Gregoric.
The research was led by Jessica Garb of the University of Massachusetts Lowell in the United States, who is also the first author of the article. In addition to US researchers, Matjaž Kuntner of the National Institute of Biology and Biological Institute of Jovan Haji ZRC SAZU and Matjaž Gregorič of the Biological Institute of Jovan Haji ZRC SAZU also participated in the research.
Research in the field of spider silk is already underway today, and researchers are working to discover everything from patterns of its evolution and genetic background to how it can be successfully synthesized in the lab. According to Gregoric, "today we can't even imagine the magnitude of a possible application when we can synthesize it really efficiently in a lab."
According to Gregoric, possible applications could be used wherever nylon and rubber materials are used – materials that are somewhat elastic but nonetheless durable. "Such materials are used in all parts of our lives, so future direct use could be for example in the manufacture of clothing and footwear, home decor, home appliances, food packaging, car tires, military equipment, parachutes, cords, tools and mechanics. engine parts, 3D printing, etc. "
Medicine is also a very interesting area of potential use. Silk is reportedly biocompatible, so according to Gregoric, it could be used for natural sutures, it could be used to close wounds and tissues, or as a lining of implants. Another potential application is to support nerve regeneration and delivery of drugs in degenerative capsules, Gregoric said.