Abstract
The mechanism of silk assembly, and thus the cues for the extraordinary properties of silk, can be explored by studying the simplest protein parts needed for the formation of silk-like materials. The recombinant spider silk protein 4RepCT, consisting of four repeats of polyalanine and glycine-rich segments (4Rep) and a globular C-terminal domain (CT), has previously been shown to assemble into silk-like fibers at the liquid-air interface. Herein, we study the interfacial behavior of the two parts of 4RepCT, revealing new details on how each protein part is crucial for the silk assembly. Interfacial rheology and quartz crystal microbalance with dissipation show that 4Rep interacts readily at the interfaces. However, organized nanofibrillar structures are formed only when 4Rep is fused to CT. A strong interplay between the parts to direct the assembly is demonstrated. The presence of either a liquid-air or a liquid-solid interface had a surprisingly similar influence on the assembly.
| Original language | English |
|---|---|
| Pages (from-to) | 11795-11805 |
| Journal | Langmuir |
| Volume | 34 |
| Issue number | 39 |
| DOIs | |
| Publication status | Published - 5 Sept 2018 |
| MoE publication type | A1 Journal article-refereed |
Funding
Spiber Technologies AB is acknowledged for providing silk proteins. FORMAS and Knut and Alice Wallenberg Foundation supported this work. The work carried out at Aalto University and VTT Ltd was supported by the Academy of Finland Center of Excellence Programme (2014−2019), the Center of Excellence in Molecular Engineering of Biosynthetic Hybrid Materials (HYBER), and Academy of Finland postdoctoral project #13311608 (2017−2020).