Bridgette Barry Professor Office: IBB 3311 Phone: 404-385-6085 Fax: 404-894-2295 E-mail Bridgette Barry Research Group Web site Georgia Tech Molecular Biophysics

A.B., Oberlin College, 1978; Ph.D., University of California, Berkeley, 1984; NIH and McKnight Postdoctoral Fellow, Michigan State University, 1985-1988

ACS Fellow, 2010; AAAS Fellow, 2008; WISE Lectureship, University of Minnesota, 2001; Edna Roe Lectureship, International Union of Photobiology, 2000; National Honorary Member, Iota Sigma Pi, 1999; Career Advancement Award, National Science Foundation, 1997; Bush Sabbatical Award, University of Minnesota, 1997; McKnight-Land Grant Professor, University of Minnesota, 1990-1993

Research Interests: Protein Biochemistry, Molecular Biophysics, Chemical Biology, Membranes

Techniques: Raman, FT-IR, and EPR Spectroscopy, Mass Spectrometry

Research in my group is focused on how the dynamic and responsive protein matrix facilitates biological catalysis.  We use a wide range of high resolution spectroscopic, biochemical, and structural techniques to describe the reaction coordinate, which reveals the motion of the protein in space and time.  We test the design principles, which we uncover, by building biomimetic models.

Current research interests:
Proton coupled electron transfer in enzymes.  We are comparing the mechanism of electron-proton transfer in photosystem II and ribonucleotide reductase.  Photosystem II is the photosynthetic reaction center responsible for the maintenance of aerobic life on earth.  Ribonucleotide reductase catalyzes the production of deoxyribonucleotides in all cells.  Ribonucleotide reductase is the target of anti-cancer therapeutics.  Both these proteins use the aromatic side chain of tyrosine as an intermediate in proton coupled electron transfer.  We seek to understand how the immense oxidizing power of the intermediary tyrosyl free radical is controlled. This research project gives a picture of the movements of the electron and proton and describes the protein conformational landscape associated with the transfer.  Elucidation of these mechanisms will develop more effective cancer therapeutic agents and new approaches in solar energy conversion. 

Biomimetic models of solar energy conversion.   Biological proton coupled electron reactions are subjected to exquisite control over direction and kinetics; these mechanisms are not yet understood.  In photosynthesis, multistep, light-driven reactions lead to the conservation of solar energy as a charge separation.  We seek to assemble nanoscale, peptide-based devices, which can carry out similar reactions.  These maquettes (or models) will provide water-soluble, stable redox agents with tunable redox potentials, kinetics, and directional control of charge transfer. These efforts will produce prototypes, which will contribute to artificial energy conversion, as well as generate new insights into important biological reactions.  We have succeeded in engineered a robust photosystem II-inspired scaffold, which exhibits a proton coupled electron transfer reaction.

Redox signaling and post-translational modification.  Oxidative stress and oxidative modifications of proteins play a role in a wide range of disease states.  We have developed a quantitative assay, which allows us to monitor the dynamics of oxidative modifications in proteins.  This gives a new method to study the cycle of damage and repair.  We are using high light stress in plants as a model system, because in plants, the level of oxidative damage can be controlled by illumination.  An immediate aim of this project is to increase the resistance of biofuel-producing plants and algae to adverse environmental conditions by engineering the damage/repair pathway.

Recent publications:

Bridgette A. Barry, Jun Chen, James Keough, David Jenson, Adam Offenbacher, and Cynthia Pagba.  (2012)  “Proton coupled electron transfer and redox active tyrosines: Structure and function of the tyrosyl radicals in Ribonucleotide Reductase and Photosystem II.”  Journal of Physical Chemistry Letters (Perspective)  In press.

James Keough, David L. Jenson, Ashley Zuniga, and Bridgette A. Barry.  (2011) "Proton coupled electron transfer and redox-active tyrosine Z in the photosynthetic oxygen-evolving complex.  "Journal of the American Chemical Society (Communication) 133, 11084–11087.

Tina M. Dreaden, Jun Chen, Sascha Rexroth, and Bridgette A. Barry.  (2011) N-formylkynurenine as a marker of high light stress in photosynthesis.” Journal of Biological Chemistry  286, 22632-22641.

Bridgette A. Barry.  (2011)  “Proton coupled electron transfer and redox active tyrosines in Photosystem II.” Journal of  Photochemistry and Photobiology B  104, 60-71.

Adam Offenbacher, Jun Chen, and Bridgette A. Barry.  (2011) “Perturbations of aromatic amino acids are associated with iron cluster assembly in ribonucleotide reductase.” Journal of the American Chemical Society 133, 6978-88.

Tina M. Dreaden, Matthew C. Johnson, B. Barquera, Bridgette A. Barry, and Ingeborg Schmidt-Krey.  (2010)  “Two-dimensional crystallization of membrane protein complexes for structure-function studies by electron crystallography.” Microscopy Book Series - Volume # 4: Microscopy: Science, Technology, Applications and Education. pp 337-346.

Gengxiang Zhao, Frederik Rudolph, Tina M. Dreaden, Matthew C. Johnson, Bridgette A. Barry, and Ingeborg Schmidt-Krey.  (2010) “Assessing two-dimensional crystallization trials of small membrane proteins for structural biology studies by electron crystallography.” J. Visualized Exp. 44,  http://www.jove.com/index/details.stp?id=1846, doi: 10.3791/1846.

Robin S. Sibert, Mira Josowicz, and Bridgette A. Barry.  (2010)  “Control of proton and electron transfer in de novo designed, biomimetic beta hairpins.”  ACS Chemical Biology 5, 1157-1168.

Jun Chen, Shana L. Bender, James M. Keough and Bridgette A. Barry. (2009) "Tryptophan as a probe of Photosystem I electron transfer reactions: A UV resonance Raman study" Journal of Physical Chemistry B 113, 11367-11370.

David L. Jenson and Bridgette A. Barry. (2009) "Proton-coupled electron transfer in Photosystem II: Proton inventory of a redox active tyrosine" Journal of the American Chemical Society 131, 10567-10573.

Adam Offenbacher, I. R. Vassiliev, M. R. Seyedsayamdost, J. Stubbe, Bridgette A. Barry. (2009) "Redox-linked structural changes in ribonucleotide reductase" Journal of the American Chemical Society 131, 7496.

Adam Offenbacher, Kimberly N. White, Indranil Sen, Allen G. Oliver, Joseph P. Konopelski, Bridgette A. Barry, Ólöf Einarsdottir. (2009) "A spectroscopic investigation of a tridentate Cu-Complex mimicking the tyrosine-histidine cross-link of Cytochrome c Oxidase" Journal of Physical Chemistry B 113, 7407-7417.