The genetic and structural diversity of spider-silk

By 06/30/2017Completed Projects
HSF 17-6 | Amount: $ 63,000 | Project Leader: A Rawal | Project Period: Jul '17 - Jul 20

A project undertaken at the School of Biological, Earth and Environmental Sciences, University of New South Wales, and supervised by Dr Aditya Rawal

Spider major ampullate (MA) silk is as extensible as rubber, stronger than steel, and tougher than Kevlar®, so is widely sought after as for a variety of practical purposes. Despite solid progress in our understanding of the biology and engineering of spider silks, we cannot produce high-quality MA silk synthetics. Unlike silkworms, spiders cannot be domesticated, which precludes harvesting utilizable quantities of silk from them. Genetic engineering of the silk proteins (spidroins) and artificial spinning are the most viable means of large scale commercial production.

Figure 1. St Andrew’s Cross spider.
Figure 2. Golden Orb Weaver spider.
Figure 3. Tent Web Spider.
Figure 4. Orb web.

We know that the amino acid compositions of the proteins and their consequent nanostructures may vary in spiders on different diets or across environments and these changes correlate with significant property variations within species However, we know very little about the interspecific variability of the silk associated genes or their ultimate effects on protein structure and silk mechanics, and this knowledge is critical for synthetic silk production.

My project aims to uncover the mechanisms enabling spiders to spin high performing silks, and why the properties of these silks vary significantly within and between spiders. The project has two primary components: (1) A fundamental research component, that will elucidate why and how spiders spin silks with such exceptional properties, and (2) an engineering component, where I will develop a biomimetic spinning protocol for the production of silk-like materials.