Although the experiment of weaving fabrics directly with spider silk failed, and although people later got a lot of inspiration from spiders and invented and produced various man-made fibers, rayon and synthetic fibers, people have not forgotten The charm of spider silk.
People still yearn for real spider silk, which can be used to weave various fabrics with special uses.
This time, it is the research findings of biologists that bring hope to people. In the 19th century, the Austrian monk Mendel planted 22 different types of peas and recorded the genetic characteristics of each type of pea offspring. In 1866, Mendel compiled and published a paper on the laws of inheritance based on his records of growing peas for 10 years. He believed that the offspring of each organism received genetic information from their parents and grandparents, so they resembled their parents and grandparents... In 1910, American biologist Morgan conducted experiments with fruit flies , also found that the offspring of fruit flies have genetic phenomena, and the rules of inheritance are the same as those summarized by Mendel.
So, what is the material that determines biological inheritance? Mendel and Morgan both proposed the hypothesis of genetic factors, believing that inherited information is determined by genetic factors. Morgan called this genetic factor a "gene."
In 1953, Watson of the United States and Clark of the United Kingdom collaborated and discovered that the genetic material is a double helix structure called DNA. DNA carries hundreds of millions of genetic codes, which convey genetic information. As long as people decipher these codes, they can obtain the required genetic characteristics according to their will.
In 1973, American scientists recombined a gene with resistance to tetracycline and a gene with resistance to streptomycin from E. coli, and transplanted it into E. coli to replicate, resulting in a new strain. It has both tetracycline resistance and streptomycin resistance. This was the first time that people created new creatures according to human will.
In 1977, people transplanted synthetic brain hormone genes into E. coli. As expected, E. coli continued to reproduce substances containing brain hormones. Brain hormone is a good medicine for treating diabetes. It can only be extracted from the brains of livestock. Only 100,000 sheep brains can extract 1 mg of brain hormone. Not only is it expensive, but in fact, only a few patients will be lucky enough to get it. Get treatment with this drug. However, using the method of transplanting brain hormone genes, now as long as there are 2 liters of E. coli culture fluid, and the E. coli continue to reproduce substances containing brain hormones based on the brain hormone genes, 1 mg of brain hormone can be extracted. In this way, not only does it no longer need to search for sheep brains, but many complicated medical treatments are saved, and the cost is greatly reduced. The price is no longer so expensive. Therefore, more patients may receive this brain hormone treatment in a timely manner.
The development of genetic science gave birth to a new discipline called genetic engineering. People only need to decipher the various codes of DNA, cut these codes, transplant them into other organisms, or transplant them into other organisms. After recombination, people can engineer organisms just like designing general engineering, and create various new organisms or biological substances that do not exist in nature but are produced according to people's will. Therefore, this emerging discipline is also called bioengineering.
Now we will talk about the inspiration of this science for people who want to get spider silk. It inspired an American molecular biologist named Stephen Lombardi. This young researcher at the Army Research Laboratory in Natick, Massachusetts, USA, considered spider silk to have many important uses from a military perspective, and molecular biology opened up a new way of thinking for him. He thought: Since molecular biology has developed to this extent, why do we have to ask spiders to produce spider silk? Can't we ask other organisms that are easy to grow and multiply quickly - like bacteria - to help.
Lombardi conducted a series of experiments. He isolated a gene from a spider called Yellow Orb Weaver, which contained the code for the production of spider silk protein; Genes transplanted into a bacterium gave the bacterium the ability to secrete spider proteins. Lombardi then used this spider silk protein to pull out a 4-inch-long spider silk.
This kind of spider silk, made from spider silk protein secreted by bacteria, has excellent properties that belong to real spider silk. Its tensile strength is 5 to 10 times that of steel wire of the same thickness; it has extremely strong toughness and can be stretched to 18% of its original length without breaking.
Moreover, comparing it with silk, it has the texture and feel of silk, but is stronger than silk and easier to dye than silk.
Although when this news was announced in the Wall Street Journal on February 26, 1991, the spider silk extracted by Lombardi was only 4 inches long, it was The hope it brings to people and the excitement it generates far exceeds the value of the 4-inch spider silk, because this achievement shows people a brand-new, feasible, cheap and high-quality spider silk that can be mass-produced. silk road.
This is because growing bacteria is much easier and simpler than raising spiders. Bacteria reproduce quickly and have very simple requirements for living conditions. In this way, people leave the complex work of producing spider silk proteins to bacteria. They can obtain a steady stream of spider silk proteins without the need for complicated equipment, and then put this spider silk proteins into the spinner to spin them extremely quickly. Pull out extremely fine spider silk at high speed, and then people can get a variety of spider silk products.
From the perspective of the U.S. military, Lombardi's invention brings good prospects for improving (reforming) military supplies. They hope that in the near future they can use spider silk to make lightweight and strong military products. For example, it can be woven into bulletproof vests to replace the Kevlar nylon bulletproof vests currently used; used to make helmets, parachutes and parachute ropes; made into tents, military uniforms, sleeping bags, bedding, etc., and may also be used to make optical fiber materials.
Of course, the emergence of spider silk protein also presents a bright future to the textile industry and clothing merchants. They imagine that in the future, this raw material can be used to weave beautiful fabrics to make noble fashions, suits and clothing. Dresses, ties, stockings...
If spiders in fairy tales were once proud that their silk could not be used by humans, then now it is time for them to be surprised. They must be very puzzled: The patent for spider silk production has been strictly kept secret for nearly 400 million years from our ancestors to the present. How come it was copied by humans in the first spring of the 1990s?