FIGURE 3. A conjectural plot of the free energy, G, for conversion of monomeric GNNQQNY, M, to the aggregated state, Mn.
From the following article:
Structure of the cross-
spine of amyloid-like fibrils
Rebecca Nelson, Michael R. Sawaya, Melinda Balbirnie, Anders Ø. Madsen, Christian Riekel, Robert Grothe and David Eisenberg
Nature 435, 773-778(9 June 2005)
doi:10.1038/nature03680

The standard free energy change
G0 for the conversion is small, so that the change in
G is controlled mainly by the concentration of monomer. At low concentrations, the monomeric state is favoured over the aggregated state, and the aggregated state is favoured at high concentrations. There is a significant kinetic barrier to formation of the aggregated state,
G‡formation. At high concentrations of protein, the barrier to re-dissolve fibres,
G‡dissolution, is very large.
