Spider silk is said to be one of the strongest, toughest materials on earth. Now engineers at Washington University in St. Louis have designed amyloid silk hybrid proteins and produced them in engineered bacteria. The resulting fibers are even stronger and tougher than some natural spider silks.
To be precise, the artificial silk, called “polymeric amyloid” fiber, was not technically produced by researchers, but by bacteria that were genetically engineered in the lab of Fuzhong Zhang, a professor in the Dept. of Energy, Environmental & Chemical Engineering in the McKelvey School of Engineering.
In 2018, Zhang’s lab engineered bacteria that produced a recombinant spider silk with performance on par with its natural counterparts in all of the important mechanical properties. Since then, he’s worked to create something even better than spider silk, using the researcher’s synthetic biology platform.
The research team, which includes first author Jingyao Li, a Ph.D. student in Zhang’s lab, modified the amino acid sequence of spider silk proteins to introduce new properties, while keeping some of the attractive features of spider silk. This work explored just three of thousands of different amyloid sequences that could potentially enhance the properties of natural spider silk.
“There seem to be unlimited possibilities in engineering high-performance materials using our platform,” Li said. “It’s likely that you can use other sequences, put them into our design and also get a performance-enhanced fiber.”
“This demonstrates that we can engineer biology to produce materials that beat the best material in nature,” Zhang said.
The research was published in the journal ACS Nano.
Sources include Scientific American and Washington University.