Amyloid fibrils as innovative catalysts for advanced functional materials

A fascinating class of nanostructures known as amyloid fibrils has garnered significant attention in the field of nanotechnology. Recent discoveries have shifted the perception of self-assembling peptide structures from disease related entities to functional tools for diverse biotechnological and material science applications.1,2 Particularly interesting are catalytic amyloids, which allow to combine the benefits of enzymatic and heterogeneous catalysts within peptide-based nanostructures. In this context, our research focuses on creating functional nanomaterials combining amyloid-like nanofibrils and artificial metalloenzymes, showcasing their potential in flow biocatalysis. For this purpose, we have selected the TTR(105-115) peptide, derived from human transthyretin, which is able to form non-toxic fibrils with unique structural properties.3 Leveraging click chemistry (SPAAC, illustrated in Figure 1), the synthetic miniaturized peroxidase FeMC6*a4 has been covalently bonded to TTR(105-115)-based fibrils. Subsequently, FeMC6*a@fibrils were implemented in a flow catalytic system by simple immobilization onto a PVDF filter membrane. This amyloid-functionalized filtering device demonstrated remarkable performance, enabling up to 40 reaction cycles of substrate (ABTS) oxidation. This approach not only enables enzyme recycling, but also facilitates the separation of reaction products. Overall, this research provides a solid foundation for exploring the catalytic capabilities of amyloid fibrils in various applications. [1] G. Wei, Z. Su, N. Reynolds, P. Arosio, I. W. Hamley, E. Gazit, R. Mezzenga, Chem. Soc. Rev. 2017, 46, 4661–4708. [2] T. P. J. Knowles, R. Mezzenga, Adv. Mater. 2016, 28, 6546 – 6561. [3] A. Fitzpatrick, G. Debelouchina, M. Bayro, D. Clare, M. Caporini, V. Bajaj, C. Jaroniec, L. Wang, V. Ladizhansky, S. Müller, C. Macphee, C. Waudby, H. Mott, A. Simone, T. Knowles, H. Saibil, M. Vendruscolo, E.V. Orlova, R. Griffin, C. Dobson, Proc. Natl. Acad. Sci. 2013, 110, 5468–5473. [4] G. Zambrano, M. Chino, E. Renzi, R. Di Girolamo, O. Maglio, V. Pavone, A. Lombardi, F. Nastri, Biotechnol. Appl. Biochem. 2020, 67, 549–562.