1 / 27

Towards a molecular movie: Transient 2D-IR spectroscopy Peter Hamm

Towards a molecular movie: Transient 2D-IR spectroscopy Peter Hamm Physikalisch Chemisches Institut, Universität Zürich. Biosystems are Dynamical. Aquaporin-1. B.L. de Groot and H. Grubmüller, Science 294, 2353-2357 (2001) http://www.mpibpc.gwdg.de/abteilungen/071/bgroot/gallery.html.

dpalos
Download Presentation

Towards a molecular movie: Transient 2D-IR spectroscopy Peter Hamm

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Towards a molecular movie: Transient 2D-IR spectroscopy Peter Hamm Physikalisch Chemisches Institut, Universität Zürich

  2. Biosystems are Dynamical Aquaporin-1 B.L. de Groot and H. Grubmüller, Science 294, 2353-2357 (2001) http://www.mpibpc.gwdg.de/abteilungen/071/bgroot/gallery.html

  3. Structure Sensitive Methods Scattering Methods (x-ray, electrons, neutrons) 2D-NMR + highest structure resolution power - works best in crystals + works best in solution + high structure resolution power - intrinsic time resolution very poor (1-100 ms) + intrinsic time resolution unlimited Time Resolved Scattering Methods 2D-IR +intrinsic time resolution fast (1 ps) - structure resolution power low but non-zero

  4. Coupled Vibrational States Linear Coupling: Site Basis Exciton Basis

  5. Linear Spectroscopy O O C O C N C N C C H H N C H H H H Frequency O H O R1 R3 C C N C C N C N C R2 O H H Frequency Strong coupling, homogeneous Weak coupling, heterogeneous R2 R3 R1

  6. 2D-IR Spectroscopy: Setup tp=100 fs Dw=200 cm-1 E=1 µJ Delay Spectrometer + 232 Element MCT Detector Array Fabry Perot Filter Sample

  7. 2D-IR Spectroscopy |2 |2‘ |1 |1‘ |0 |0‘

  8. 2D-IR Spectroscopy |20 |11‘ |02‘ |10 |01‘ |00‘

  9. 2D-IR Spectroscopy: Equilibrium • Conformation and distribution of conformations  Ultrafast equilibrium fluctuations Probe Frequency [cm-1] Woutersen et al. J. Phys. Chem. B, 104, 11316-11320 (2000) Woutersen et al., PNAS 98, 11254-11258 (2001) Woutersen et al. J. Chem. Phys.117, 6833-6840 (2002)

  10. Our Dream: Molecular Movie

  11. Photocleavable Peptide ? hn C. Kolano, K. Gomann, W. Sander, Eur. J. Org. Chem.2004, 20, 4167-4176.

  12. Photocleavable Peptide: IR spectrum Boc-Cys-Pro-Aib-Cys-OMe

  13. Equilibrium 2D Spectrum 1 ps t 2D-IR

  14. Equilibrium 2D Spectrum 1 ps t 2D-IR

  15. Equilibrium 2D Spectrum 1 ps t 2D-IR

  16. Transient 2D Spectroscopy: Setup IR Probe Fabry Perot Filter IR Pump Spectrometer + 232 Element MCT Detector Array Delay UV Switch Delay Sample Flow-Cell

  17. Transient 2D-IR Spectra 3-100 ps 1 ps t UVpump IRpump IRprobe 3 ps 25 ps 100 ps

  18. Nonequilibrium MD Simulations 1 ns Equilibrium Simulation (NVT): 120 ns Bondbreaking: Remove S-S Bond Non-Equilibrium Simulation (NVE): 600 ps • MD Package: Gromacs; Gromos Force Field 43a1 • Starting geometry: Based on low-resolution x-ray structure • Solvent box: Acetonitrile (1048 molecules)

  19. MD Simulations: Example Trajectories 3.0 Å

  20. MD Simulations: Average 6.1 Å 3.0 Å +s -s

  21. Transient 2D-IR Spectra Equilibrium 2D Transient 2D 100 ps C. Kolano, Nature 2006 in press

  22. Transient 2D-IR Spectra Equilibrium 2D Transient 2D 100 ps

  23. Transient 2D-IR Spectra Equilibrium 2D Transient 2D 100 ps

  24. And Finally: The Movie

  25. Conclusion Transient 2D-IR spectroscopy combines picosecond time resolution with microscopic structural information Transient 2D-IR reveals new insight into fast structural dynamics of peptides, that cannot be obtained otherwise.  An ultrafast molecular movie of the 3D- structure conceivable (in connection with isotope labeling)

  26. Outlook: Isotope Labelling a-Helix Folding 13C=O 13C=18O 13C=O 13C=18O hn

  27. Acknowledgement • University Zürich University Munich • - Dr. Christoph Kolano - Prof. Wolfgang Zinth • Dr. Jens Bredenbeck • Dr. Jan Helbing University Bochum • Mariusz Kozinski - Dr. Christoph Kolano • Valentina Cervetto - Prof. Wolfram Sander • Harald Bregy • Ellen Backus Max Planck Institut, Martinsried • Virgiliu Botan - Dr. Christian Renner • - Prof. Luis Moroder • Max Born Institut, Berlin • Dr. Sander Woutersen University of Toronto • Prof. Thomas Elsaesser- Prof. Andrew Woolley • University FrankfurtFinancial Support • Prof. Josef Wachtveitl - Universität Zürich • Prof. Gerhards Stock - Swiss Science Foundation • - Deutsche Forschungsgemeinschaft

More Related