NR AOUL
AU Kaimann,T.K.; Jansen,K.; Metzger,S.; Riesner,D.
TI Structural characterization of alpha-helical dimers of recombinant PrP 90-231
QU International Conference - Prion diseases: from basic research to intervention concepts - TSE-Forum, 08.10.-10.10.2003, Gasteig, München - Poster session - BR-34
PT Konferenz-Poster
AB
Structural transitions of the prion protein are fundamental events in the formation of infectious PrPsc. This conversion from a conformation with PrPc-like properties i.e. solubility and alpha-helical structure to a PrPsc-like conformation, with its insolubility and beta-sheet rich structure can be induced in vitro by slight changes of solvent conditions, i.e. low concentrations (< 0.1%) of the anionic detergent SDS. A non-covalent dimer of alpha-helical PrP was found at SDS-concentrations of 0.055-0.07 % and was discussed as a potential first step in the conversion process (1). In this work the structural properties of the dimer were analyzed by chemical cross-linking, using EDC as a zero-length cross-linking reagent. The sites of contact between both PrP molecules were determined by tryptic digestion and identifying the resulting peptides by mass spectrometry. Two peptides, PrP90-106 and PrP195-204, are apparently involved in forming the chemical cross-link. Further work will focus on the direct identification of the cross-linked peptides via 18O-labeling of the C-terminus. The cross-linking technique will also be applied to determine contact sites in oligomeric beta-sheet-rich structures in order to get a better insight in the mechanism of prion-protein conversion.
1) Jansen et al. (2001) Biological Chemistry 382 683-691
AD T.K. Kaimann, K. Jansen, D. Riesner, Heinrich-Heine-Universität, Institut für Physikalische Biologie and Biologisch-Medzinisches-Forschungszentrum, Düsseldorf, Germany; S. Metzger, Biologisch-Medzinisches-Forschungszentrum, Heinrich-Heine-Universität-Düsseldorf, Germany
SP englisch
PO Deutschland