Warren F. Beck
Department of Chemistry
Michigan State University
East Lansing, Michigan 48824 USA
Office: Room 3 Chemistry; 517/355-9715 x213. Fax: 517/353-1793
Email: beckw at msu.edu
Laboratories: Rooms 4, 6, 16, 40, and 52 Chemistry
Vitae: B.S. 1982, Davidson College; Ph.D., Yale University, 1988 (with Gary Brudvig); Miller Institute Postdoctoral Fellowship, University of California, Berkeley, 1989-91 (with Kenneth Sauer); Assistant Professor, 1991-1998, Vanderbilt University; Associate Professor, Vanderbilt University, 1998; Associate Professor, Michigan State University, 1999-present.
Honors: Phi Beta Kappa (1982); National Science Foundation Graduate Fellowship (1982–1985); Kent Fellowship, Department of Chemistry, Yale University (1982–1986); Richard Wolfgang Dissertation Prize, Department of Chemistry, Yale University (1988); Miller Institute Postdoctoral Fellowship, University of California, Berkeley (1989–1991); Searle Scholarship, Chicago Community Trust/Searle Scholars Program (1992–1995); Lilly Endowment Teaching Fellowship (1993–1994); Cottrell Scholars Award, Research Corporation (1994).
Teaching
CEM 384: Introduction to Physical Chemistry II, Spring 2010
Current Research
My group employs ultrafast laser spectroscopy and time-resolved fluorescence spectroscopy to study reaction dynamics in condensed phases and in proteins. Our current efforts focus on on the dynamics of proteins displaced far from the equilibrium (or native) structure and on coupled intermolecular vibrational modes in electron-transfer reactions in redox proteins and in photosynthetic reaction centers.
The Beck laboratory acknowledges support from the National Science Foundation's Biomolecular Systems Cluster (MCB-092010).
Nonequilibrium Protein Dynamics
This project employs femtosecond and picosecond time-resolved fluorescence spectroscopy to study how proteins evolve structurally when they are displaced from the native structure. We have recently discovered that vibrational energy transferred from an electronic chromophore can be exploited to drive structural transitions of the host protein from the native fold to a range of partially unfolded states that probably correspond to late intermediates along the folding/unfolding pathway. Because we generate the intermediate structures optically under conditions that favor the native structure, the dynamics of refolding can be characterized subsequently with independent control of the solvent temperature or composition. The electronic chromophore serves as a solvatochromic probe of the structure of the surrounding protein's structure during the formation and decay of the vibrationally generated intermediates.
Intermolecular Vibrational Coherence and Electron Transfer
This project addresses the structural origin and dynamical role of the vibrational modes in the 100-cm-1 regime that are coupled to long-distance electron-transfer reactions in the photosynthetic reaction center and in redox proteins. Our results show that these modes predominantly arise from intermolecular interactions with clustered molecules in the first solvation shell. Not only do the intermolecular modes have a dominant impact on the electron-transfer dynamics by controlling the Marcus reorganization energy and hence the overall activation energy for the reaction, they control the structural reorganization that occurs in response to the formation of net charges in the product states. This is a trapping reorganization that plays an important role in determining the reversibility of the electron-transfer reactions in photosynthesis. In order to detect these interactions selectively in bacteriochlorophyll and porphyrin systems, we use a time-domain version of resonance Raman spectroscopy that is performed with femtosecond pump–probe, dynamic-absorption and transient-grating methods.
Recent Publications
Dillman, K. L.; Shelly, K. R.; Beck, W. F. Vibrational coherence in polar solutions of ZnII tetrakis(N-methylpyridyl)porphyrin with Soret-band excitation: rapidly damped intermolecular modes with clustered solvent molecules and slowly damped intramolecular modes from the porphyrin macrocycle. J. Phys. Chem. B 2009, 113, 6127–6139.
Barns, K. J.; Lampa-Pastirk, S.; Dillman, K. L.; Wegener, A. J.; Beck, W. F. Intramolecular vibrational excitation of unfolding reactions in ZnII-substituted and metal-free cytochromes c: activation enthalpies from integrated fluorescence Stokes shift and lineshape excitation profiles. J. Phys. Chem. B 2008, 112, 15108–15115.
Shelly, K. R.; Golovich, E. C., Dillman, K. L., and Beck, W. F. "Intermolecular vibrational coherence in the bacteriochlorophyll proteins B777 and B820 from Rhodospirillum rubrum." J. Phys. Chem. B 2008, 112, 1299–1307.
Lampa-Pastirk, S.; Beck, W. F. “Intramolecular vibrational preparation of the unfolding transition state of Zn(II)-substituted cytochrome c.” J. Phys. Chem. B 2006, 110, 22971–22974. Featured as the cover article for the 23 November 2006 issue.
Shelly, K. R.; Golovich, E. C.; Beck, W. F. “Intermolecular vibrational coherence in bacteriochlorophyll a with clustered polar solvent molecules.” J. Phys. Chem. B 2006, 110, 20586–20595.
Lampa-Pastirk, S.; Beck, W. F. “Polar solvation dynamics in Zn(II)-substituted cytochrome c: diffusive sampling of the energy landscape in the hydrophobic core and solvent-contact layer.” J. Phys. Chem. B 2004, 108, 16288–16294.
Lampa-Pastirk, S.; Lafuente, R. C.; Beck, W. F. “Excited-state axial-ligand photodissociation and nonpolar protein-matrix reorganization in Zn(II)-substituted cytochrome c.” J. Phys. Chem. B 2004, 108, 12602–12607.
Carson, E. A.; Diffey, W. M.; Shelly, K. R.; Lampa-Pastirk, S.; Dillman, K. L.; Schleicher, J. M.; Beck, W. F. “Dynamic-absorption spectral contours: vibrational phase-dependent resolution of low-frequency coherent wave-packet motion of IR144 on the ground-state and excited-state π→π* surfaces.” J. Phys. Chem. A 2004, 108, 1489–1500.
Shelly, K. R.; Carson, E. A.; Beck, W. F. “Vibrational coherence from the dipyridine complex of bacteriochlorophyll a: intramolecular modes in the 10–220-cm-1 regime, intermolecular solvent modes, and relevance to photosynthesis.” J. Am. Chem. Soc. 2003, 125, 11810–11811.
Beck, W. F. “Ultrafast Spectroscopy.” In Encyclopedia of Chemical Physics and Physical Chemistry; Moore, J. H., Spencer, N. D., Eds.; Institute of Physics Publishing, Ltd.: Bristol, England, 2001; Volume II, pp 1743–1772.