Surface-based assembly

A surface or interface can influence the assembly of fibrils by altering both the process and kinetics of fibril nucleation or elongation. This behavior is not surprising as surface properties are known to influence the absorption, confirmation, and destabilization of globular proteins or smaller peptides (Rocha et al., 2005). Surface properties influence fibril assembly in a similar way by altering the absorption, unfolding, and aggregation of monomers. 

A number of studies have examined fibril formation in the presence of different solid nonbiological surfaces, as summarized in Table 1. While many of these studies have focused on the formation of fibrils, the wettability and RMS of some surfaces have been characterized. Typical surface contact angles are also presented in Table 1 to aid comparison between these surface-based experiments. 

Surface Properties Polypeptide Fibril formation Reference 

Regenerated cellulose (RE) Contact angle 27° 2, RMS - 87 nm Human insulin Nucleation faster than bulk Nayak et al. (2008) 

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An understanding of the interaction between polypeptides and surfaces is imperative if self-assembly is to be achieved in a reproducible manner. This is especially important if the scale of assembly is to be increased from small-scale laboratory experiments to larger reaction vessels. Insights obtained into surface-based assembly can also be used to design surface-based "reactor platforms" which encourage surface interactions in order to achieve... 

External microscopy tools can be used to further control the surface-based assembly of fibrils on a surface. Kowalewski used an AFM tip to move the initial aggregates that first form during fibril assembly and change their position on a surface (Kowalewski and Holtzman, 1999). An AFM tip has also been used to induce fibril disassembly in restricted areas (Kellermayer et al., 2008), and both methods offer a way to create patterns of fibrils on a surface. 

Two types of expression systems based on plant RNA viruses have been developed for production of immunogenic peptides and proteins in plants epitope presentation systems (short antigenic peptides fused to the CP that are displayed on the surface of assembled viral particles) and polypeptide expression systems (these systems express the whole unfused recombinant protein that accumulates within the plant). 

Paul van der Schoot, Nucleation and Co-Operativity in Supramolecular Polymers Michael J. McPherson, Kier James, Stuart Kyle, Stephen Parsons, and Jessica Riley, Recombinant Production of Self-Assembling Peptides Boxun Leng, Lei Huang, and Zhengzhong Shao, Inspiration from Natural Silks and Their Proteins Sally L. Gras, Surface- and Solution-Based Assembly of Amyloid Fibrils for Biomedical and Nanotechnology Applications... 

Sally L. Gras, Surface- and Solution-Based Assembly of Amyloid Fibrils for Biomedical and Nanotechnology Applications... 

Surface- and Solution-Based Assembly of Amyloid Fibrils... 

Supramolecular Nanostructures of Phthalocyanines and Porphyrins at Surfaces Based on the Bottom-Up Assembly ... 

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