The engineered protein combines the flexibility and tensile strength of spider silk with the resilience of silica and has been used to form unique nanocomposite materials.
David Kaplan, Carole Perry and colleagues developed a fusion protein made of the spider silk and the silica-cored proteins of microscopic algae called diatoms. Silica can be difficult to produce in a factory, requiring high heat, but producing silica is relatively easy in diatoms, where it can be done at normal temperatures in water.
Taking advantage of silk’s self-assembling properties, the researchers made films and fibres out of the resulting fusion proteins. The fused silica particles formed in a narrow range of sizes, unlike natural ones, which can have a broad range.
The ability to control such sizing in silica particles could be used for industrial and biomedical applications and new nanocomposites. The researchers say the technique may allow the production of other tough minerals, metals, and composites that are difficult to fabricate in industrial settings under ambient conditions.