1. Prion Project - Update Mass Spectrometry of Prions Andy Lo, Béla Reiz, Messele Fentabil Dr. Liang Li Department of Chemistry University of Alberta

2. Mass Spectrometry (MS)  Mass Spectrometry is an instrumental method used to identify chemical substances by means of the separation of their gaseous ions using magnetic and/or electric fields according to their mass-to-charge ratio.

3. MS in PROTEOMICS  Molecular weight of proteins  Masses of peptides in a mixture  Masses of fragment ions of a peptide

4. Experimental Procedure Database Search

5. Protein MS

6. Experimental Procedure Database Search

7. PrP Tryptic Digest - MS

8. PrP&Myo Tryptic Digest - MS

9. Experimental Procedure Database Search

10. PrP&Myo Tryptic Digest LC-MALDI-MS

11. Experimental Procedure Database Search

12. PrP&Myo Tryptic Digest LC-MALDI-MSMS

13. Experimental Procedure Database Search

14. Database Search Results

18. PrP Chymotryptic Digest LC-MALDI

19. PrP Chymotryptic Digest Results

23. Future Work Chemical surface modification of surface exposed residues using:  N-bromosuccinimide (NBS) for Trp exposed residues  Hydroxylation of surface exposed Cys, Trp, Tyr, Met

24. Thanks!  Dr. Liang Li  Andy and Messele  All Li Group members