Review Protein families, natural history and biotechnological aspects of spider silk (original) (raw)

FUNPEC-RP www Protein families, natural history and biotechnological aspects of spider silk

Spiders are exceptionally diverse and abundant organisms in terrestrial ecosystems and their evolutionary success is certainly related to their capacity to produce different types of silks during their life cycle, making a specialized use on each of them. Presenting particularly tandemly arranged amino acid repeats, silk proteins (spidroins) have mechanical properties superior to most synthetic or natural high-performance fibers, which makes them very promising for biotechnology industry, with putative applications in the production of new biomaterials. During the evolution of spider species, complex behaviors of web production and usage have been coupled with anatomical specialization of spinning glands. Spiders retaining ancestral characters, such as the ones belonging to the Mygalomorph group, present simpler sorts of webs used mainly to build burrows and egg sacs, and their silks are produced by globular undifferentiated spinning glands. In contrast, Araneomorphae spiders have a complex spinning apparatus, presenting up to seven morphologically distinct glands, capable to Review ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 11 (3): 2360-2380 (2012)

Protein families, natural history and biotechnological aspects of spider silk

Genetics and Molecular Research, 2012

ABSTRACT. Spiders are exceptionally diverse and abundant organisms in terrestrial ecosystems and their evolutionary success is certainly related to their capacity to produce different types of silks during their life cycle, making a specialized use on each of them. Presenting particularly tandemly arranged amino acid repeats, silk proteins (spidroins) have mechanical properties superior to most synthetic or natural high-performance fibers, which makes them very promising for biotechnology industry, with putative applications in the ...

Bioengineering of spider silks for the production of biomedical materials

Frontiers in Bioengineering and Biotechnology

Spider silks are well known for their extraordinary mechanical properties. This characteristic is a result of the interplay of composition, structure and self-assembly of spider silk proteins (spidroins). Advances in synthetic biology have enabled the design and production of spidroins with the aim of biomimicking the structure-property-function relationships of spider silks. Although in nature only fibers are formed from spidroins, in vitro, scientists can explore non-natural morphologies including nanofibrils, particles, capsules, hydrogels, films or foams. The versatility of spidroins, along with their biocompatible and biodegradable nature, also placed them as leading-edge biological macromolecules for improved drug delivery and various biomedical applications. Accordingly, in this review, we highlight the relationship between the molecular structure of spider silk and its mechanical properties and aims to provide a critical summary of recent progress in research employing recom...

Molecular mechanisms of spider silk

Experientia, 2006

Spiders spin high-performance silks through the expression and assembly of tissue-restricted fibroin proteins. Spider silks are composite protein biopolymers that have complex microstructures. Retrieval of cDNAs and genomic DNAs encoding silk fibroins has revealed an association between the protein sequences and structure-property relationships. However, before spider silks can be subject to genetic engineering for commercial applications, the complete protein sequences and their functions, as well as the details of the spinning mechanism, will require additional progress and collaborative efforts in the areas of biochemistry, molecular biology and material science. Novel approaches to reveal additional molecular constituents embedded in the spider fibers, as well as cloning strategies to manipulate the genes for expression, will continue to be important aspects of spider biology research. Here we summarize the molecular characteristics of the different spider fibroins, the mechanical properties and assembly process of spidroins and the advances in protein expression systems used for recombinant silk production. We also highlight different technical approaches being used to elucidate the molecular constituents of silk fibers.

Spider silk: A natural marvel of mechanical and structural strength

African Journal of Biological Sciences, 2021

The spider silk fibers have unique high performance properties that make it a desirable model for artificial fibers and its performance under benign conditions has important implications for biomimicry. It has tensile strengths comparable to steel and some are nearly as elastic as rubber on a weight to weight basis. The spider spins its silk at ambient temperatures, low pressures and with water as solvent. Spiders are ectotherms and the ambient temperature affects the spinning speed and the mechanical and structural properties of the silk spun. The high cytocompatibility and low immunogenicity of spider silk fibers make them well suited for biomaterial products such as nerve conduits. Spider silk proteins have been shown to be soluble in ionic liquids, thus once soluble, they can be processed into new biomaterials such as films, gels, porous sponges, bone tissue engineering. The spider silk chains with a fixed molecular weight decreases exponentially with the UV irradiation time, since UV irradiation causes the chemical bonds in the protein chains to undergo cleavage. This paper reviews related literature on the spider silk spinning process, conditions and their effects on structure, mechanical properties of spider silk and its resistance to UV degradation. As a bonus, a brief review of the biotechnological production of recombinant spider silk us presented.

Spider Silk: Structure and application

International Journal of Scientific and Research Publications (IJSRP), 2020

the nature is full of mysteries and engages the full minded persons and scholars to itself throughout the world, the nature presents these mysteries on a wide variety of events and inside the complex world of different creatures. There are millions of creatures that have individually strange characteristics and life condition. There are things that are in-depth scientific and debate-raising facts with these creatures which most of them are hidden and need to be discovered. Spider silk and webs are one of this mysteries. Due to low rate of degradability, toughness, elasticity and biosynthetic characteristics, the spider silk evaluated to have many scientific uses and application. Hence here in this paper, I a bit more want to discuss on spider silk uses and application on some of life-related matters. And a bit on its structure and specifications.

Spider Silk: The Network of Fibre

TJPRC, 2013

Spider silk, also known as gossamer, is a protein fiber spun by spiders. It is one of the most sought after biomaterial .Spider silk is one of nature’s most extraordinary substances. Due to its demand, and unavailability, it has even acquired the nickname, ‘Holy Grail’. This silk comes from the glands of the spider and is both flexible and light weight. It is exceptionally flexible, elastic, and lightweight, yet tough—three times as strong as Kevlar and five times as strong as steel!. And because it is natural, it is biodegradable and can be produced pollution-free. Furthermore, one of the most important qualities of spider silk is its endless versatility. Because of its less availability, spider silk is manufactured synthetically. Spider silk, synthetically made, could be used in countless applications with significant commercial impact and improvement to human life. X-ray diffraction studies have shown that the silk is composed of long amino acid chains that form protein crystals. Amino acids are composed of fibroin and sericin proteins which consists of 8- 10 Poly - alanine blocks and 24-35 glycine blocks. Fibroin - 40% glycine ,29% alanine ,10% glutamine,4% tyrosine, 3% proline and serine, leucine, valine, and arginine in less amount. The elasticity of spider silk is due to glycine-rich regions .The resulting beta-sheet crystals crosslink the fibroins into a polymer network with great stiffness, strength and toughness. This crystalline component is embedded in a rubbery component that permits extensibility. Dragline silk has more energy-absorbing capability than Kevlar and can absorb up to ten times more energy. The possible uses for synthetic spider silk are endless. They include applications in the industrial (high tension cords etc), Medical (drug delivery, Nerve guides) and military fields as well as in everyday uses. Spider silks could be used to create strong and flexible artificial ligaments and tendons, bandages and surgical thread. Spider silk could also be used to construct protective clothing or body armor. Current research focuses around these problems and a possible solution would be to adapt the composition of silk proteins to alter its properties. Research is still in its early stages but unraveling the secrets of spider silk is underway. Nevertheless, the strength and resilience of spider silk has amazed people for thousands of years, reading around, on and off the web, we get a lot of facts about the strength of spider silk that sometimes seem contradictory, although they all agree that spider silk is way stronger than any other silk or natural material.