Yeast Sup35 Prion Structure: Two Types, Four Parts, Many Variants.

The yeast [] prion, formed by the Sup35 (eRF3) protein, has multiple structural variants differing in the strength of nonsense suppressor phenotype. Structure of [] and its variation are characterized poorly. Here, we mapped Sup35 amyloid cores of 26 [] ex vivo prions of different origin using proteinase K digestion and mass spectrometric identification of resistant peptides.