Biophysicist Irina Iachina, University of Southern Denmark, holds a silk fiber, produced by a golden orb-web spider. Credit: Anders Boe/University of Southern Denmark
Various researchers desire open the amazing ability of spiders to spin silk threads that are immensely strong, light-weight, and versatile. Pound for pound, spider silk is more powerful than steel and harder than Kevlar. No one has been able to reproduce the spiders work.
If we ever manage to develop an artificial equivalent with these attributes, an entire new world of possibilities may open: Artificial spider silk might change products like Kevlar, polyester, and carbon fiber in industries and be used, for instance, to make flexible and lightweight bulletproof vests.
Postdoc and biophysicist Irina Iachina from the Department of Biochemistry and Molecular Biology, University of Southern Denmark (SDU), is included in this race to discover the recipe for extremely silk. She has actually been captivated by spider silk considering that her time as a masters trainee at SDU, and presently, she is investigating the subject at the Massachusetts Institute of Technology in Boston with support from the Villum Foundation.
Various scientists aim to unlock the remarkable capability of spiders to spin silk threads that are profoundly strong, light-weight, and versatile. Pound for pound, spider silk is more powerful than steel and tougher than Kevlar. The different studies exposed that the spiders silk fiber consists of at least two outer layers of lipids, i.e., fats. Illustration from the Scientific Reports paper: Schematic representation (not to scale) of the proposed structure of a spider silk fiber as discovered in the present work. These proteins are produced by the spider when it creates its silk fibers.
Biophysicist Irina Iachina, University of Southern Denmark, studying spider silk on a computer. Credit: Anders Boe/University of Southern Denmark
As part of her research study, she is collaborating with associate professor and biophysicist Jonathan Brewer at SDU, who is a professional in using various types of microscopes to peer into biological structures.
Together, they have now, for the very first time, studied the internal parts of spider silk utilizing an optical microscopic lense without cutting or opening the silk in any method. This work has now been published in the journals Scientific Reports and Scanning.
” We have utilized several advanced microscopy methods, and we have likewise established a brand-new type of optical microscopic lense that enables us to look all the way into a piece of fiber and see whats inside,” explains Jonathan Brewer.
The golden orb web spider produces its silk from its rear end. Credit: Anders Boe/University of Southern Denmark
So far, spider silk has been examined utilizing different methods, all of which have actually offered brand-new insights. Nevertheless, there have actually also been downsides to these techniques, as Jonathan Brewer explains, since they frequently need cutting the silk thread (likewise called fiber) available to obtain a cross-section for tiny examination or freezing the samples, which can alter the structure of the silk fibers.
” We wished to study unmanipulated and pure fibers that have not been cut, frozen, or manipulated in any way,” states Irina Iachina.
For this purpose, the research study duo utilized less intrusive strategies such as Coherent Anti-Stokes Raman Scattering, Confocal Microscopy, Ultra-resolution Confocal Reflection Fluorescence Depletion Microscopy, Scanning Helium Ion Microscopy, and Helium Ion Sputtering.
The different research studies exposed that the spiders silk fiber consists of a minimum of two external layers of lipids, i.e., fats. Behind them, inside the fiber, there are various so-called fibrils running in a straight, tightly loaded side-by-side arrangement (see illustration). The fibrils have a size ranging between 100 and 150, which is listed below the limitation of what can be determined with a regular light microscopic lense.
Illustration from the Scientific Reports paper: Schematic representation (not to scale) of the proposed structure of a spider silk fiber as discovered in today work. (A) Fibre side view, (B) cross-section through fiber. An external, non-conductive lipid-rich layer (green) of between 0.6 to 1 µm density, two conductive, inner autofluorescent protein layers: one which FITC shows higher affinity towards (blue), and another Rhodamine B shows a greater affinity towards (orange). The inner protein core consists of crystalline fibrils, aligned parallel to the long axis of the fiber, surrounded by more amorphous protein areas. Credit: Iachina/Brewer, University of Southern Denmark.
” They are not twisted, which one may have pictured, so now we understand that there is no need to twist them when trying to create artificial spider silk,” states Irina Iachina.
Iachina and Brewer work with silk fibers from the golden orb-web spider, Nephila Madagascariensis, which produces 2 different types of silk: One, called MAS (Major Ampullate Silk fibers), is utilized to build the spiders web, and it is also the silk the spider utilizes to hold on. Irina Iachina describes it as the spiders lifeline; it is extremely strong and has a diameter of around 10 micrometers.
The other, called MiS (Minor Ampullate Silk fibers), acts as an auxiliary product for the building. It is more elastic and normally has a diameter of 5 micrometers.
According to the duos analysis, the MAS silk consists of fibrils with a diameter of roughly 145 nanometers. These proteins are produced by the spider when it creates its silk fibers.
Comprehending how they can develop such strong fibers is essential, however the fibers are also challenging to produce. Therefore, researchers in this field often rely on spiders to produce the silk for them.
Alternatively, they can turn to computational methods, which is what Irina Iachina is presently working on at MIT: “Right now, I am doing computer simulations of how proteins transform into silk. The goal is, naturally, to find out how to produce synthetic spider silk, however I am also thinking about contributing to a higher understanding of the world around us,” she states.
Recommendations: “Nanoscale imaging of significant and small ampullate silk from the orb-web spider Nephila Madagascariensis” by Irina Iachina, Jacek Fiutowski, Horst-Günter Rubahn, Fritz Vollrath and Jonathan R. Brewer, 24 April 2023, Scientific Reports.DOI: 10.1038/ s41598-023-33839-z.
” Helium Ion Microscopy and Sectioning of Spider Silk” by Irina Iachina, Jonathan R. Brewer, Horst-Günter Rubahn and Jacek Fiutowski, 22 May 2o23, Scanning.DOI: 10.1155/ 2023/2936788.
