Simone Hornemann1,2,3, Christian Schorn1,2,3, Kurt Wüthrich1,2,3
1GlaxoSmithKline R&D Limited, Old Powder Mills, Tonbridge TN11 9AN, UK
2Institut für Molekularbiologie und Biophysik, Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland
3Zurich Open Repository and Archive University of Zurich University Library Strickhofstrasse 39 CH-8057 Zurich
Tóm tắt
NMR structures of recombinant prion proteins from various species expressed in Escherichia coli have been solved during the past years, but the fundamental question of the relevancy of these data relative to the naturally occurring forms of the prion protein has not been directly addressed. Here, we present a comparison of the cellular form of the bovine prion protein isolated and purified from healthy calf brains without use of detergents, so that it contains the two carbohydrate moieties and the part of the GPI anchor that is maintained after enzymatic cleavage of the glycerolipid moiety, with the recombinant bovine prion protein expressed in E. coli. We show by circular dichroism and 1H‐NMR spectroscopy that the three‐dimensional structure and the thermal stability of the natural glycoprotein and the recombinant polypeptide are essentially identical. This result indicates possible functional roles of the glycosylation of prion proteins in healthy organisms, and provides a platform and validation for future work on the structural biology of prion proteins, which will have to rely primarily on the use of recombinant polypeptides.
