Peptide Nanotubes

Nanotubular structures can form from a variety of different materials such as inorganic, carbon, biological microtubules, porins, viral proteins, α-lactalbumin, amyloid proteins, DNA, lipids carbohydrates, synthetic polymers, and other organic systems. Molecular self-assembly is the main bottom-up approach for the affordable production of bulk quantities of well-defined nanostructures. Biological building blocks such as DNA, lipids, and viruses are extensively studied for this purpose.

Proteins and peptides are the most versatile natural molecular bricks, due to their extensive chemical, conformational and functional diversity. They also offer specificity of interactions, necessary for biosensing, catalytic and molecular recognition processes, and scalable production either through chemical synthesis or genetic engineering. Due to the high complexity of proteins, there is a difficulty associated with the thorough understanding of the physical and chemical principles that underpin and control their self-assembling properties.

Simple model systems and short peptides offer a much more viable route to gaining a quantitative and systematic insight into protein-like self-assembly. Here we review the emerging field of self-assembling nanotubes made of simple peptide building blocks, and discuss their morphologies, applications and the future outlook. We start with the simplest systems and work towards increasingly complex systems.