Determining the mechanical properties of amyloid-like nanosheets by applying plate theory on its elastic network model

Pathological prion proteins are amyloidogenic proteins that are known to disrupt the normal func-tioning cells inside the human cerebrum. Typically having a fibrillar shape, these proteins are known to infect other normally functioning prion proteins when it is fractured caused by external conditions. Moreover, prion proteins are known to change their conformation from fibrillar to nanosheet form according to the pH condition. As these proteins possess highly undegrading fea-tures and infectivity, studies about determining the pathological mechanism of prion proteins are carried out with effort. Even so, the information of amyloid-like HET-s prion protein, a fungal prion protein in Podospora Anserina, in its nanosheet form still remains elusive. In this study, we determined the mechanical and vibrational characteristics of HET-s nanosheet structure, which forms at pH ∼4 and resembles a skewed plate, using in silico methods. Combining skewed plate theory with Rayleigh-Ritz approximation method into HET-s nanosheet structures at various length scale, we found that these nanosheets have mechanical properties comparable to those of previously reported biological 2-D nanomaterials. Our observation provides a detailed structural information on amyloid-like HET-s nanosheets, which may be related to its infectious characteristics.