Researchers at Karolinska Institutet and Suzhou University in China produced spider silk fibers without causing environmental damage (Shutterstock)

Like a professional chef who has his own recipes that make his food delicious and delicious, spiders use a natural molecular enhancer to strengthen their silk, and the competition between researchers was to come up with this special recipe and implement it in an environmentally friendly way, which is what a Chinese research team claims they have succeeded in doing.

One of the effective methods that researchers proposed in the past to produce fibers similar to spider silk was to introduce elements that make up the amyloid protein with spider silk proteins (spidroin), which gave positive results in producing silk similar in strength and durability to what a spider produces.

But on the other hand, it had negative environmental and health effects, which is the problem that the research team from Karolinska Institutet and Suzhou University in China addressed in the new study published in the journal “Advanced Functional Materials.”

Spider silk proteins, also known as “spidroins,” are the basic building blocks of spider silk. They are manufactured and stored inside specialized glands in the spider’s abdomen, called “silk glands.” Spiders have several types of them, and each produces a different type of silk for different purposes, such as capturing Prey, web building, or cocoon formation.

The spider silk production process includes several steps:

  • Genetic transcription and translation

    : Within the silk glands, specialized cells produce the silk protein “spidroin” through the processes of genetic transcription and translation. It is usually manufactured in the form of long, repetitive protein chains containing regions with different sequences of amino acids. These sequences determine the properties of the resulting silk, such as its strength and elasticity. And its adhesion.

  • Storage

    : Once manufactured, spiderroin is stored in a concentrated form within the silk glands until needed, and the silk glands act as reservoirs, keeping it in liquid form.

  • Extrusion

    : When a spider needs to use silk, it presses its silk glands to squeeze out the liquid, forcing it to pass through a narrow channel called the spindle. When it passes through the spindle, it undergoes a transformation from liquid to solid fiber through a process known as “spinning,” which includes This process aligns and arranges the spidroin molecules into a highly organized structure, resulting in the formation of silk fibers.

  • Hardening

    : Once taken out of the spindle, the silk fibers harden through processes such as dehydration or exposure to air, forming strong, flexible threads.

The spider produces silk through 4 stages to use it for several purposes, including catching prey (Shutterstock)

How is spider silk produced in the laboratory?

Attempts to produce spider silk in the laboratory began with the arrival of a method to produce spider silk proteins using recombinant DNA technology, through the following:

  • Gene isolation

    : Researchers have isolated the genes responsible for encoding spider silk proteins from the spiders' genome, and these genes contain the instructions for its production.

  • Recombinant DNA technology

    : Using recombinant DNA technology, scientists insert the spider silk gene into a host organism, such as bacteria, yeast, or other types of cells. This allows them to use the host organism's cellular machinery to produce spider silk proteins.

  • Expression and purification

    : The host organism then synthesizes spider silk proteins based on the inserted gene. Scientists can engineer the host organism to produce large amounts of the desired spider silk proteins. After production, the proteins are purified from the host cells to remove any contaminants.

  • Processing and Spinning

    : Once purified, the spider silk proteins are processed to form a liquid. This solution can then be spun into fibers using various techniques, such as wet spinning or dry spinning. During spinning, the liquid is extruded through a spinneret to form continuous fibres, which harden into silk threads when Pull it out.

Previous attempts to produce spider silk fibers generated toxic feedstocks (Shutterstock)

Between the past and Chinese penetration

The silk resulting from spider silk proteins, "spidroin", which was produced in the laboratory, was not as strong as what occurs naturally, and the spiders still had a "craftsmanship secret" that research teams tried to find.

Previous attempts found that introducing elements that make up the amyloid protein into silk protein helps in producing natural silk with the same strength as spider silk. But on the other hand, the problem was that when introducing these elements into spider silk proteins, there was a risk of generating intermediate materials. Toxic during self-assembly process.

A statement issued by the Chinese Karolinska Institute explains that the achievement achieved in the new study lies in describing a method to achieve the goal of mimicking the strength of natural spider silk without generating any toxic intermediates, as they used a type of molecular enhancers called “separating domains,” which self-assemble into fibers. They mimic amyloid through pathways that avoid the formation of toxic intermediates.

“Separator domains” are parts of proteins that act as “separators” between functional domains or regions within the protein structure, so that they help the protein get rid of some of its defects, while maintaining its general structure and function. The domains used in this study were designed to self-assemble into fibrils. They resemble amyloid without producing the toxic intermediates, meaning they provide the same strengthening effect without the harmful side effects.

By incorporating these spacer domains into spider silk proteins, they were able to increase the mechanical strength of the silk-like fibers, making it appear as if they had discovered the secret of the spider's craftsmanship, which they confirmed through experiments comparing natural spider silk and the silk they produced using spider silk protein. "Spiderwine" and separating domains.

In these experiments, the researchers used “microscopy,” which is based on a scanning electron microscope, which provides high-resolution images of silk fibers. This technique involves scanning a focused beam of electrons on the surface of the silk sample.

By detecting interactions between the beam and the sample surface, researchers can create detailed images that show the shape and topography of silk fibers at the nanoscale.

Passport for applications... 3 conditions

The researchers' success in eliminating the problem of toxicity when trying to imitate spider silk promises to allow it to be used in many applications, as pointed out by Khaled Al-Kholy, professor of textile engineering at Assiut University (southern Egypt).

Al-Khouli said in a telephone interview with Al Jazeera Net that it can be used in many industries, including textiles, aerospace, and biomedical engineering. For example, it can be used to create stronger, more lightweight materials for clothing, umbrellas, or medical implants.

He adds that the biocompatible nature of spider silk makes it suitable for biomedical applications, as it can be used to create scaffolds for tissue engineering, drug delivery systems, or surgical sutures that require high strength and biocompatibility.

But before this product obtains a pass for these applications, Al-Kholy specifies three conditions that researchers must work on in subsequent studies. These conditions are:

  • First

    : further studies should be conducted to fully evaluate the biocompatibility and safety of the improved silk fibers for various applications, especially in biomedical contexts.

  • Second

    : Despite the positive results, researchers need to ensure that they have reached the maximum degree of strength, and therefore subsequent studies must be conducted that may lead to increased strength, by making modifications in the structure of the spacer domains, or exploring additional modifications to the silk proteins.

  • Third

    , scaling up the production of spider silk fibers for commercial applications will require efficient and cost-effective manufacturing processes, and subsequent studies should describe how to manufacture on a commercial scale.

Source: websites