Sorrentino Angela, Giosafatto Concetta Valeria L, Sirangelo Ivana, De Simone Carmela, Di Pierro Prospero, Porta Raffaele, Mariniello Loredana
Department of Food Science, University of Naples, Napoli, Italy.
Biochim Biophys Acta. 2012 Oct;1822(10):1509-15. doi: 10.1016/j.bbadis.2012.06.003. Epub 2012 Jun 13.
Prion proteins are known as the main agents of transmissible spongiform encephalopathies affecting humans as well as animals. A recombinant ovine prion protein was found to be in vitro able to act as an effective substrate for a microbial isoform of transglutaminase, an enzyme catalyzing the formation of isopeptide bonds inside the proteins. We proved that transglutaminase modifies the structure of the prion protein by leading to the formation of three intra-molecular crosslinks and that the crosslinked protein form is more competent in amyloid formation compared to the unmodified one. In addition, the crosslinked prion protein was shown also to be more resistant to proteinase K digestion. Our findings suggest a possible use of transglutaminase in stabilizing the prion protein three-dimensional structure in order to investigate the molecular basis of the conversion of the protein into its pathological form.
