Until now, prions were only seen in the cells of eukaryotic organisms such as plants and animals. In the latest study, researchers analysed roughly 60,000 bacterial genomes using software trained to recognize prion-forming proteins in yeast. They focused on a section of the bacterial protein Rho. In many bacteria, such as C. botulinum and E. coli, Rho is a global regulator of gene expression, meaning that it can control the activity of many genes. When the potentially prion-forming section of Rho taken from C. botulinum was inserted into E. coli, clumps of malformed proteins that are characteristic of most prions formed. Moreover, when the protein snippet was inserted into yeast, it could replace the functions of a known prion-forming yeast protein.
