Understanding amyloid aggregation by statistical analysis of atomic force microscopy images

• Published in: Nature nanotechnology Vol. 5; no. 6; pp. 423 - 428
• Main Authors: Jung, Jin-Mi, De Los Rios, Paolo, Mezzenga, Raffaele, Adamcik, Jozef, Dietler, Giovanni, Flakowski, Jérôme
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 01.06.2010
• Subjects: Amyloid - chemistry; Amyloid - ultrastructure; Animals; Cattle; Coagulation; Food; Food processing; Lactoglobulins - chemistry; Lactoglobulins - ultrastructure; Microscopy; Microscopy, Atomic Force - methods; Models, Statistical; Nanostructures - chemistry; Nanostructures - ultrastructure; Nanotechnology; Physics; Polymers; Protein Denaturation; Protein Multimerization; Proteins; Statistical analysis; Switzerland
• ISSN: 1748-3387; 1748-3395
• DOI: 10.1038/nnano.2010.59

The aggregation of proteins is central to many aspects of daily life, including food processing, blood coagulation, eye cataract formation disease and prion-related neurodegenerative infections. However, the physical mechanisms responsible for amyloidosis-the irreversible fibril formation of various proteins that is linked to disorders such as Alzheimer's, Creutzfeldt-Jakob and Huntington's diseases-have not yet been fully elucidated. Here, we show that different stages of amyloid aggregation can be examined by performing a statistical polymer physics analysis of single-molecule atomic force microscopy images of heat-denatured beta-lactoglobulin fibrils. The atomic force microscopy analysis, supported by theoretical arguments, reveals that the fibrils have a multistranded helical shape with twisted ribbon-like structures. Our results also indicate a possible general model for amyloid fibril assembly and illustrate the potential of this approach for investigating fibrillar systems.