  X-ray crystallography and nuclear magnetic resonance (NMR) spectroscopy are
two powerful tools to determine the protein 3D structure. However, not all
proteins can be successfully crystallized, particularly for membrane proteins.
Although NMR spectroscopy is indeed very powerful in determining the 3D
structures of membrane proteins, same as X-ray crystallography, it is still
very time-consuming and expensive. Under many circumstances, due to the
noncrystalline and insoluble nature of some proteins, X-ray and NMR cannot be
used at all. Computational approaches, however, allow us to obtain a
description of the protein 3D structure at a submicroscopic level.
  To the best of the authors' knowledge, there is little structural data
available to date on the AGAAAAGA palindrome in the hydrophobic region
(113-120) of prion proteins, which falls just within the N-terminal
unstructured region (1-123) of prion proteins. Many experimental studies have
shown that the AGAAAAGA region has amyloid fibril forming properties and plays
an important role in prion diseases. Due to the noncrystalline and insoluble
nature of the amyloid fibril, little structural data on the AGAAAAGA is
available. This paper introduces a simple molecular modelling strategy to
address the 3D atomic-resolution structure of prion AGAAAAGA amyloid fibrils.
Atomic-resolution structures of prion AGAAAAGA amyloid fibrils got in this
paper are useful for the drive to find treatments for prion diseases in the
field of medicinal chemistry.
