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Joined the faculty
in 2000
Ph.D., Czech Academy of Sciences, Prague (1997) M.S., Charles University at Prague (1992) 
Our work is
focused on synthesis of novel pigments, chromophores, photoluminescent
and electroluminescent materials as well as investigation of optical
properties of materials capable of changes in color and luminescence
for various real-life applications. More specifically we develop
photonic materials and devices in two main areas: supramolecular
materials for molecular sensing and materials that can be used in
fabrication of OLEDs.
In the first area of research, we synthesize new supramolecular materials with interesting photonic and/or conductor properties. These polymeric materials are designed to change their photophysical or electrical properties as a result of association with other materials and species. As a part of this research we prepare new conjugated and/or semiconducting polymers with backbone-integrated receptors that are known to bind and sense biologically important materials such as anions, nucleotide phosphates and nucleotide-phosphonate based virostatics. Additionally, we are exploring self-assembled organometallic dendrimers capable of vectorial energy transfer, which is used to relay the information about the presence of various analyte The second main research area in the group is oriented toward the design and synthesis of new chromophores for applications in flat displays and development of OLED materials. Here we focus on synthesis of electroluminescent coordination polymers. 
Takizawa, S.; Montes, V. A.; Anzenbacher Jr., P.: Phenylbenzimidazole-Based New Bipolar Host Materials for Efficient Phosphorescent OLEDs. Chem. Mater. 2009, in press.
Benor, A.; Takizawa, S.; Chen, P.; Pérez-Bolivar, C.; Anzenbacher Jr., P.: Dramatic efficiency improvement in phosphorescent OLEDs with ultraviolet-ozone treated PEDOT:PSS. Appl. Phys. Lett. 2009, 94, in press. Anzenbacher Jr, P.; Palacios, M. A.: Polymer nanofibre junctions of attolitre volume serve as zeptomole-scale chemical reactors. Nature Chem. 2009, 1, 80-86. DOI: 10.1038/nchem.125. This article was highlighted in The New York Times, Nature, Chemistry & Engineering News, ChemWorld, MIT Technology Review, Spektrumdirekt, C2W, and others. Montes, V. A.; Zyryanov, G. V.; Danilov, E.; Agarwal N.; Palacios, M.; Anzenbacher Jr., P.: Ultrafast Energy Transfer in Oligofluorene−Aluminum Bis(8-hydroxyquinoline)acetylacetone Coordination Polymers. J. Am. Chem. Soc. 2009, 131, 1787-1795; DOI: 10.1021/ja805175w. Anzenbacher Jr., P.; Montes, V. A.; Takizawa S.: High-purity white light from a simple single dopant host-guest white organic light-emitting diode architecture. Appl. Phys. Lett. 2008, 93, 163302. DOI: 10.1063/1.3005424.
Joined the
faculty in 2007
Ph.D., University of Texas at Austin B.S., University of Michigan
D.W. Sloan, P.M. Blass and J.M. White
"Surface Chemistry of Precursors for Film Growth: Pentakisdimethylamido Tantalum"
Appl. Surf. Sci. 143 (1999) 142-152.
M. Brust, P.M. Blass, and A. J. Bard "Self-Assembly of Photoluminescent Cu(I)-Dithiol Multilayer Thin Films and Bulk Materials" Langmuir, 13 (1997) 5602-5607. A. Kamath, B.Y. Kim, P.M. Blass, Y.M. Sun, J.M. White, and D.L. Kwong "Oxidation Resistance of Ultrathin Silicon Nitride Passivation Layers on Si(100)" Mater. Res. Soc. Symp. Proc., 477, (1997) 341-346. A. Kamath, B.Y. Kim, P.M. Blass, Y.M. Sun, J.M. White, and D.L. Kwong "Growth Chemistry of Ultrathin Silicon Nitride and Oxynitride Passivation Layers on Si(100)" Mater. Res. Soc. Symp. Proc. 477, (1997) 335-340. A. Kamath, D.L. Kwong, Y.M. Sun, P.M. Blass, S. Whaley, and J.M. White "Oxidation of Si(100) in Nitric Oxide at Low Pressures: an X-ray-photoelectron Spectroscopy Study" Appl. Phys. Lett. 70(1), (1997) 63-65.
Joined the
faculty in 1969
Ph.D., U.C.L.A. (1956) B.S., City College of New York (1948)
Currently, we
are studying the blood coagulation cascade and are examining the effect
of acetaldehyde upon the coagulation components. This relates directly
to the effect of alcohol metabolites upon the enzymes, zymogens,
protease inhibitors and glycosaminoglycans, such as heparin.
Additionally, we are chemically modifying heparin and studying the
anticoagulant effects of its analogs. Finally, the effect of
acetaldehyde on hypertension, hypotension, pancreatitis, and emphysema
are being explored.
In separate studies, we are quantitating the effect of protamine sulfate and other small peptides with hormonal potential on the interaction of blood coagulation factors with antithrombin III.
A.S. Brecher,
S.J. Murrey, K.D. Gray, and J.N. Poulimenos. Anticoagulant effect of
captopril. J. Cardiovascular Pharmacol., 2007, In Press.
A.S. Brecher and R. Dubord. Captopril and Lisinopril decrease acetaldehyde effects upon prothrombin time. Digestive Diseases & Sciences, 2007, In Press. A.S. Brecher and R. Dubord. Effect of acetaldehyde upon cathepsin G and chymase. NRAS implications. Digestive Diseases & Sciences, 2007, In Press. E.A. Suchocki and A.S. Brecher. The effect of acetaldehyde on human plasma factor XIII function. Dig. Dis. Sci. 2007, Apr. 10 (Epub ahead of print). A.S. Brecher, A.R. Moon, and K.D. Gray. The effect of acetaldehyde-glycosaminoglycan mixtures upon Factor IXa and Factor IX-Deficient Plasma. ALCOHOL, (2006) 39, 97-104.
Joined the faculty
in 1989
Ph.D., Cornell University (1986) M.S., University of California - Riverside (1980) B.S., University of California - Riverside (1979)
Our research is
focused on determining the structures of conformationally flexible
molecules and the effect that solvation and hydrogen bonding has on
these structures. To carry out these investigations we make use of
vibrationally resolved electronic spectroscopy in the ultracold
environment of a supersonic jet expansion. Electronic spectroscopy
permits structural information to be obtained on both ground and
excited electronic states through analysis of the resolved vibrational
structure that appears under these conditions.
We are currently investigating a number of phenyl substituted amines and amides. These types of molecules form strong hydrogen bonds with a variety of partners, including water, and have the potential to act as both donors and acceptors. By studying hydrogen bonded clusters at high spectral resolution it is possible to determine the mode of binding between the solute and solvent as well as to characterize the structural perturbations that arise from the strong interaction.
"Conformations of
Isolated Model Dipeptides in Supersonic Jet Expansions", Cable, J. R.;
Sharp, J. C.; Miller, N. J. Phys. Chem A, submitted.
"The infrared spectroscopy of H-bonded bridges stretched across the cis-amide group: II. Ammonia and mixed ammonia/water bridges", Fedorov, A. V.; Cable, J. R.; Carney, J. R.; Zwier, T. S. J. Phys. Chem A2001, 105, 8162. "The infrared spectroscopy of H-bonded bridges stretched across the cis-amide group: I. Water bridges", Carney, J. R.; Fedorov, A. V.; Cable, J. R.; Zwier, T. S. J. Phys. Chem A2001, 105, 3487. "Spectroscopy of hydrogen-bonded formanilide clusters in a supersonic jet: Solvation of a model trans amide", Fedorov, A. V.; Cable, J. R. J. Phys. Chem. A2000, 104, 4943.
Joined the
faculty in 1998
Ph.D., The Johns Hopkins University (1996) M.A., The Johns Hopkins University (1993) B.A., Clark University (1991) NSF Career Recipient
Since the end of
2002, a significant focus of our "basic" research program involves the
investigation of supra-nanosecond and ultrafast photophysical processes
in platinum(II) polyimine chromophores bearing a variety of
carbon-based ligands. These strongly-coupled metal-organic systems are
of fundamental interest and may serve in a variety of applications
including optical power limiting, solar energy conversion, and
photocatalysis. We are currently developing new synthetic methodologies
for the preparation of novel platinum structures. Our interest in the
design and photophysical characterization of metal-organic chromophores
facilitates our fruitful collaboration with the Ziessel group
(Strasbourg, France), where we continue to investigate the
photophysical properties of p-conjugated metal-organic complexes. On
the more "applied" side my group continues to develop novel inorganic
compounds with pendant photochromic quenchers and their associated
polymeric materials for nondestructive luminescence readout,
potentially useful for binary optical data storage in both read-only
and read-write-erase formats. In these systems, the luminescence
response from the metal complex indirectly signals the photochromic
state of the quencher, circumventing direct interrogation of the
photochemically active species (nondestructive readout). Collaborators
at the NMRC in Cork, Ireland have used our molecules in near-field
spectroscopy in an effort to produce ultrahigh density binary memory
systems with information bits of sub-micron size. A recent extension of
our work in this area demonstrated the concept of optical data storage
using luminescence lifetime modulation/readout. In 2005 we started to
explore the solid-state vapochromism (color changes in response to
VOCs) inherent in some of the platinum(II) MLCT complexes described
above. We recently illustrated the concept of low power photon
upconversion using simple photochemical concepts, highlighted as "News
of the Week" in C&EN (August 8, 2005). This year we also
established a new program in solar energy conversion, focusing largely
on the design and synthesis of new Ru(II) inorganic chromophores for
dye sensitized solar cells.
Currently Research Interests: Supramolecular Photochemistry & Photophysics of Metal-Organic Systems Ultrafast and Supra-nanosecond Spectroscopy of Inorganic and Organometallic Compounds Solar Energy Conversion, Photovoltaics & Photocatalysis Vapochromic, Thermochromic, and Photochromic Responsive Materials Lifetime-Based Sensing Applications of Luminescent Inorganic Dyes Long-Range Photo-Initiated Electron and Energy Transfer Multi-Photon Photochemistry, Nonlinear Excitation Processes & Low Power Photon UpconversionPhotocrystallography
Influence of Temperature on Low-Power Upconversion in Rubbery Polymers. Singh-Rachford, T.N.; Lott, J.; Weder, C.; Castellano, F.N. J. Am. Chem. Soc. 2009, 131, 12007-12014. Nonlinear Photochemistry Squared: Quartic Light-Power Dependence Realized in Photon Upconversion. Singh-Rachford, T.N.; Castellano, F.N. J. Phys. Chem. A 2009, 113, 9266-9269. Evolution of the Triplet Excited State in PtII Perylenediimides. Danilov, E.O.; Rachford, A.A. Goeb, S.; Castellano, F.N. J. Phys. Chem. A 2009, 113, 5763-5768. Solvent-induced Configuration Mixing and Triplet Excited State Inversion: Insights from Transient Absorption and Transient DC Photoconductivity Measurements. She, C.; Rachford, A.A.; Wang, X.; Goeb, S.; El-Ballouli, A.O.; Castellano, F.N.; Hupp, J.T. Phys. Chem. Chem. Phys. 2009, 11, 8586-8591. [Pt(mesBIAN)(tda)]: A Near-Infrared Emitter and Singlet Oxygen Sensitizer. Rachford, A.A.; Hua, F.; Adams, C.J.; Castellano, F.N. Dalton Trans. 2009, 3950-3954.
Joined the
faculty in 2007
Ph.D., University of Wisconsin-Madison (1998) B.S., Harvey Mudd College (1993)
Joined the
faculty in 1969
Ph.D., University of Rochester (1968) B.S., Bradley University (1963)
Development of
laboratory instruments suitable for introductory chemistry teaching
labs. Microprocessor programming and chemical applications. Molecular
dynamics of small atomic clusters, with particular interest in
stability and growth following low energy collisions; energy transfer
in the collision of highly anharmonic small molecules.
N/A
Joined the
faculty in 2009
Ph.D., Purdue University (2009) B.A., Saint Olaf College, Northfield, MN (2001)
Joined the
faculty in 2006
Ph.D., University of Florida, 2003 B.A., Belgrade University, Yugoslavia, 1999
I am interested
in a study of coupled proton and electron motion in hydrogen-bonded D/A
systems. Electron transfer (ET) mediated by hydrogen bonds (H-bonds) is
essential to the function of redox proteins in many biological
processes, particularly photosynthesis and respiration. Apart from
providing a medium for ET, H-bonds in ET proteins have other functions.
For example, ET in biological systems is often accompanied with a
proton transfer along a certain H-bonded surface with the goal to
achieve catalytic activity or drive proton pumps. Even though some
insight into the general ET and proton transfer pathways in proteins
has been obtained, a full understanding of the coupled effects that
proton and electron motion have on each other is yet to be achieved.
Apart from its significance in biological systems, the understanding of ET through H-bonded systems will be valuable for the development of future devices. For example, the design of an efficient solar cell requires a donor/acceptor (D/A) system with a long-lived charge separated state. To achieve this goal, a specific H-bonded D/A system can be envisioned in which the initial charge separation induces the proton motion along the H-bonded surface and makes the charge recombination highly inefficient. In other words, the H-bonded surface could act as a unidirectional gate for the electron flow in D/A systems. In order to obtain information on both electron and proton dynamics, we use two techniques: VIS pump-VIS probe and VIS pump-IR probe spectroscopy. After excitation using a VIS pump beam, the ET processes is studied by probing the transient species in the VIS spectral region, while the proton motion is observed by probing the vibrational modes of the transient species in the IR region. The model compounds are designed with the goal to elucidate the mechanism of coupled electron and proton motion both along H-bonded D/A systems and along H-bonded D/water/A systems.
G. Li, K. Parimal, S. Vyas, C. M. Hadad, A. H. Flood, K. D. Glusac, "Pinpointing the Extent of Electronic Delocalization in the Re(I)-to-Tetrazine Charge Separated Excited State Using Time-Resolved Infrared Spectroscopy", J. Am. Chem. Soc, 2009, 131, 11656-11657.
G. Li, K. D. Glusac, "The Role of Adenine in Fast Excited-State Deactivation of FAD: a Femtosecond Mid-IR Transient Absorption Study", J. Phys. Chem. B, 2009, 113, 9059-9061. P. Kucheryavy, G. Li, S. Vyas, C. M. Hadad, K. D. Glusac, "Electronic Properties of 4-Substituted Naphthalimides", J. Phys. Chem. A, 2009, 113, 6453-6461. G. Li, V. Sichula, K. D. Glusac, "Role of Adenine in Thymine-dimer Repair by Reduced Flavine-Adenine Dinucleotide", J. Phys. Chem. B, 2008, 112, 10758-10764. G. Li, K. D. Glusac, "Light-Triggered Proton and Electron Transfer in Flavin Cofactors", J. Phys. Chem. A, 2008, 112(20); 4573-4583
Joined the
faculty in 1971
Ph.D., University of Illinois (1963) A.B., Bowling Green State University (1958)
Our program in
natural products/bio-organic chemistry is concerned with the synthesis
and biological evaluation analogs of plant derived phenolic compounds
known to be inhibitors of tumor formation. Ellagic acid, present in
various fruits and vegetables, particularly strawberries, is a planar
biaryl polyphenol. Epigallocatechin gallate (EGCG) is a flavanoid
polyphenol found in high concentration in brewed green tea. Analogs,
chosen on the basis of computerized molecular modeling studies, are
being synthesized.
A long- term program in the chemistry of strained bicyclic ring compounds is proceeding in the areas of synthesis, mechanism and spectroscopy. We are particularly interested in partially fluorinated bicyclo[2.1.0] pentanes. Flash vacuum pyrolysis techniques have allowed us to synthesize several novel non-natural molecules.
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Joined the
faculty in 1987
Ph.D., Yale University, New Haven (1986) A.M., Harvard University (1980) B.S., Ohio State University (1977)
Nucleic Acids
(DNA and RNA) play diverse roles in living organisms. Not only do they
encode genetic information but they actively participate in its readout
from transcription to translation, including splicing, editing, and
regulation at each stage. Single-stranded DNA and RNA molecules fold
into complex 3-dimensional structures to carry out these roles. We are
investigating the logic of the 3D architecture of these molecules using
an integrated biophysical, biochemical, and bioinformatic approach.
These complex structures are able to specifically bind other molecules,
including potential drug molecules. Photosensitizers that can
specifically bind DNA or RNA molecules have tremendous potential for
overcoming present limitations of photodynamic therapy, by directing
damage to molecules specific to the target cells. We are investigating
the binding of potent photosensitizers to complex nucleic acids using
biophysical and biochemical methods. See also: Geometric Classification
of Non-Canonical Basepairing.
The RNA structure alignment ontology. Brown JW, Birmingham A, Griffiths PE, Jossinet F, Kachouri-Lafond R, Knight R, Lang BF, Leontis N, Steger G, Stombaugh J, Westhof E. RNA. 2009 Sep;15(9):1623-31. Epub 2009 Jul 21. Frequency and isostericity of RNA base pairs. Stombaugh J, Zirbel CL, Westhof E, Leontis NB. Nucleic Acids Res. 2009 Apr;37(7):2294-312. Epub 2009 Feb 24. Classification and energetics of the base-phosphate interactions in RNA. Zirbel CL, Sponer JE, Sponer J, Stombaugh J, Leontis NB. Nucleic Acids Res. 2009 Aug;37(15):4898-918. Epub 2009 Jun 14. Annotation of tertiary interactions in RNA structures reveals variations and correlations. Xin Y, Laing C, Leontis NB, Schlick T. RNA. 2008 Dec;14(12):2465-77. Epub 2008 Oct 28. TokenRNA: a new type of sequence-specific, label-free fluorescent biosensor for folded RNA molecules. Afonin KA, Danilov EO, Novikova IV, Leontis NB. Chembiochem. 2008 Aug 11;9(12):1902-5.
Joined the faculty
in 2006
Ph.D., Columbia University (1991) M.S., Peking University, P.R. China (1984) Ohio Eminent Scholar
Our research is
focused on the use of single molecule techniques to understand
molecular dynamic processes and the effects of the local environment on
these processes. We have been developing and applying time-resolved,
nanoscale site-specific, single molecule methods that are an effective
alternative to conventional methods, providing information under
conditions most applicable to the natural processes underlying the area
of research interest. Single-molecule approaches are useful and unique
in studying heterogeneous and complex systems because the inhomogeneity
can be identified and/or removed by studying one molecule at a time.
Single molecules and molecular complexes can be observed as they
traverse a wide range of energy states in real-time and the effect of
this ever changing "system configuration" on chemical/biological
reactions and other dynamical processes can be mapped.
Our current research work has been focused on (1) conformational dynamics and reaction in proteins and protein complexes under physiological conditions, and our long-term goal is to study single-molecule protein conformational dynamics and reactions in living cells; and (2) inhomogeneous interfacial chemical and biological reaction dynamics in solar energy conversion, bioremediation, and environmental systems, focusing on fundamental understanding of the controlling physical and chemical properties, such as, Franck-Condon coupling and barrier, vibrational and solvent relaxation energetics, molecular distributions, redox states identification, and molecular motions.
Yufan He, Xiaohua Zeng, Saptarshi Mukherjee, Suneth Rajapaksha, Samuel Kaplan, H. Peter Lu, "Revealing Linear Aggregates of Light Harvesting Antenna Proteins in Photosynthetic Membranes," Langmuir (2009) ASAP electronically published. Yuanmin Wang, Xuefei Wang, and H. Peter Lu, "Probing single-molecule interfacial geminate electron-cation recombination dynamics,” J. Am. Chem. Soc. 131, 9020–9025 (2009). H. Peter Lu, "Single-Molecule Protein Interaction Conformational Dynamics," Current Pharmaceutical Biotechnology, 10, 522-531 (2009). H. Peter Lu, "Combined Single-Molecule Electrical Recording and Single-Molecule Spectroscopy Studies of Ion Channel Conformational Dynamics," an invited book chapter in Methods in Nano Cell Biology, edited by Bhanu Jena, ELSEVIER (2009). Yuanmin Wang, Xuefei Wang, Sujit Kumar Ghosh, H. Peter Lu, "Probing single-molecule interfacial electron transfer dynamics of porphyrin on TiO2 nanoparticles," J. Am. Chem. Soc. 131, 1479-1487 (2009).
Joined the
faculty in 2005
Ph.D., University of Toledo (2004) B.S., University of Southern Indiana (1996)
Joined the
faculty in 1987
Ph.D., Ohio State University (1978) B.A., St. John's University (1974)
Dr. Midden was
co-founder of the first full-featured residential learning community at
BGSU, the "Chapman Learning Community " (CLC). This program was cited
nationally by the Joint Task Force on Student Learning of AAHE, ACPA
and NASPA in its report of best examples of how learning communities
enhance undergraduate education (Joint Task Force on Student Learning
1998). Evidence of the effectiveness of CLC includes higher retention
rates, higher student satisfaction, and higher GPAs when CLC
participants are compared to another group of BGSU first-year students
matched on high school GPA, ACT scores, size of high school, type of
home town, socio-economic levels and other relevant factors. CLC has
been extremely effective in enhancing and increasing collaboration at
all levels, including student-student, student-faculty,
faculty-faculty, faculty-residence hall staff as well as three-way
collaborations involving all participants. Dr. Midden is also the
founder and director of the International Clearinghouse and Registry
for Residential Learning Communities:
http://www.bgsu.edu/colleges/as/clc/rlcch/. He has made many
presentations at regional and national professional meetings on various
aspects of residential learning communities and their role in
increasing student academic achievement, engagement and satisfaction. A
few examples follow.
Midden, W.R.;
Klein, T.: "The Chapman Learning Community" AAC&U National Meeting
on "Learning Communities: Strategies for Strengthening Connections,
Competence, and Commitments" Providence, RI Mar 1-3, 2001.
Schoem, D.L.; Midden, W.R.; Minor, F.; Levine, J.: "Critical Issues in Living/Learning Communities" joint presentation by Univ. of Michigan, BGSU & Univ. of Missouri, 6th Annual Learning Communities Conference, Chicago, IL Nov 7-9, 2001. Midden, W.R.; Schoem, D.L.: "Benefits of Residential Learning Communities-The Student Perspective" facilitation of panel of students at the 6th Annual Learning Communities Conference, Chicago, IL Nov 7-9, 2001. Midden, W.R.; Klein, T.D.; Richardson, S.M.; Craft, W.; Hinds, C.; Bushman, D.: "The Costs of Learning Communities: What Are They & Are They Worth It?" 85th Annual Meeting of the Association of American Colleges and Universities, San Francisco, CA, Jan. 28-30, 1999.
Joined the
faculty in 1973
Ph.D., University of Kansas (1963) A.B., Hope College (1960) Retired in 2009
Joined the
faculty in 1991
Ph.D., Northwestern University (1988) M.S., Northwestern University (1983) B.A., Oberlin College, Ohio (1980)
Our group is
developing a new class of hybrid inorganic/biological materials
possessing novel photochemical properties.
In one project we are using the principles of "metalloprotein design" to prepare a new class of miniature metalloproteins containing luminescent Cu(I) centers. The photophysical properties of these systems have been found to mimic many features found in natural photosynthetic reaction centers and can be used to develop new routes towards solar energy conversion. A related project uses supramolecular coordination chemistry to direct the assembly of novel peptide structures. We have found that such metal-mediated peptide assemblies possess a diverse range of morphologies ranging from nanometer-scale hollow spheres to nano-cylinders, making them possible candidates for drug delivery vehicles. Thus, a central theme of our laboratory is to combine inorganic coordination chemistry/photochemistry with protein design in order to prepare new types of hybrid materials which possess potentially useful chemical properties.
Metal-mediated
Peptide Assembly: Use of Metal Coordination to Change the
Oligomerization State of an a-helical Coiled-coil, Tsurkan, M. V. and
Ogawa, M Y., Inorg. Chem. 2007, 46, 6849-6851.
Electron-Transfer Functionality into Synthetic Metalloproteins from the Bottom-up, (Inorganic Forum Article), Hong, J, Kharenko, O. A. and Ogawa, M. Y., Inorg. Chem. 2006, 45, 9974-9984. Electron-Transfer Functionality of Synthetic Coiled-coil Metalloproteins, Ogawa, M. Y., Fan, J., Fedorova, A., Hong, J. Kharenko, O. A., Kornilova, A. Y., Lasey, R. C., Xie, F. J. Braz. Chem. Soc. 2006, 17, 1516-1521. A Miniature Cu(I) Metalloprotein Undergoes Collisional Electron-transfer in the Inverted Marcus Region, J. Hong, O. A. Kharenko, A. K. Petros, B. R. Gibney, and M. Y. Ogawa, Angew. Chem. Int. Ed. 2006, 37, 6137-6140. Cu(I) Luminescence from the Tetranuclear Cu4S4 Cofactor of a Synthetic 4-Helix Bundle O. A. Kharenko, D. C. Kennedy, B. Demeler, M. J. Maroney, and M. Y. Ogawa, J. Am. Chem. Soc. 2005, 127, 7678.
Joined the
faculty in 2006
Ph.D., M.S., University of Bologna, Italy (1988)
We use
conventional and novel computational tools to investigate the
reactivity of organic and biological molecules in their electronically
excited states. One major target of our work is the mapping of the
photon-induced "force field" which sets an equilibrium molecular
structure into motion in realistic molecular environments (e.g. in
solution or in a protein cavity). This force field can be calculated
and represented in terms of photochemical reaction paths: ie. paths
that start on an excited state potential energy surface and end on the
ground state energy surface. Photochemical reaction paths comprise
mechanistic elements that are not involved in the description of
thermal reactions. These correspond to real crossings of different
potential energy surfaces. For photochemical reactions prompted by
direct irradiation these crossings often correspond to conical
intersections that are regarded as the photochemical analogues of
transition states. Given the central role of photochemical reaction
paths and conical intersections (as well as singlet/triplet surface
crossings) in the investigation of the excited state reactivity of
proteins (e.g. biological photoreceptors) or solvated molecules (e.g.
dyes in solution), we also develop computational strategies based on a
combination of ab-initio quantum chemical methods and molecular
mechanics methods that allow to study the effects of light irradiation
on complex molecular systems.
Pär Söderhjelm, Charlotte Husberg, Angela Strambi, Massimo Olivucci, Ulf Ryde, Protein Influence on the Electronic Spectra Modeled by Multipoles and Polarizabilities, 2009 J. Chem. Theo. Comp. 5, 649-658. Rivado-Casas, L.; Sampedro, D.; Campos, P. J.; Fusi, S.; Zanirato, V.; Olivucci, M. J Org Chem 2009, 74, 4666-4674. Andruniów, T.; Olivucci, M. Journal of Chemical Theory and Computation 2009, 55-90. IN PRESS Pistolesi, S.; Sinicropi, A.; Pogni, R.; Basosi, R.; Ferré, N.; Olivucci, M. J Phys Chem B 2009. IN PRESS Adalgisa Sinicropi, Caterina Bernini, Riccardo Basosi and Massimo Olivucci, A novel biomimetic photochemical switch at work: design of a photomodulable peptide, Photochem. Photobiol. Sci., 2009, DOI: 10.1039/b906271h
Joined the
faculty in 1988
Ph.D., University of Manchester, England Retired in 2009
Joined the
faculty in 1974
Ph.D., University of Minnesota B.S., Lebanon Valley College
Our general
interests are in the regulation of eukaryotic gene expression,
primarily at the transcriptional level. This includes studies on
transcription factor binding to promoter elements in the genes within
DNA, within nucleosomes and how this relates to in vitro transcription
utilizing reporter genes. In addition, in many of these studies the
impact of the coactivator protein, HMGB1, on the thermodynamic and
kinetic binding processes is investigated, in addition to its role in
the expression of the gene (transcriptional activity).
We have studied many of the proteins involved in the assembly of the preinitiation complex (PIC) on TATA-containing promoters. These include the TATA-binding protein (TBP), TFIIB, TFIIA and HMGB1. We are currently focusing a great deal of our efforts on the understanding how hormone-responsive genes are regulated by their ligand-activated nuclear hormone receptors. In this regard, we have shown that although the estrogen receptors (ER), alpha & beta, do bind to their "classical" palindromic recognition sequences (ERE, estrogen response elements) that contain a 3 bp spacer, their high binding affinity extends far beyond this, including an individual half-site of the ERE,(referred to as HERE). The importance of HEREs is becoming more apparent as more extensive data from the human genome are harvested, including findings from ChIP (chromatin immunoprecipitation) and Chip-CHIP (chromatin immunoprecipitation coupled with DNA microchip) assays. These findings suggest that HEREs may play an important role in the regulation of estrogen-responsive genes and that the binding of ER to DNA is much more promiscuous than currently accepted models present.
Das, D.,
Peterson, R. C. & Scovell, W. M., HMGB1 High Mobility Group B1
Proteins Facilitate Strong Estrogen Receptor Binding to Classical and
Half-site Estrogen Response Elements and Relax Binding Selectivity,
Mol. Endocrinol., 18, 2616-2632 (2004).
Dasgupta & W. M. Scovell, Competition Between HMGB1 and EIA with TFIIA in the Early Stages of Assembly of the Transcriptional Preinitiation Complex, Biochim. Biophys. Acta, 1627, 101-110 (2003). D. Das & W. M. Scovell, The Binding Interaction of HMG-1 with the TATA-Binding Protein/TATA Complex, J. Biol. Chem. 276, 32597-35605 (2001). Selected as "Hot Paper" in Chromatin Structure and Function. W. Lu, R. Peterson, A. Dasgupta & W. M. Scovell, Influence of HMG-1 and Adenovirus Oncoprotein E1A on Early Stages of Transcriptional Preinitiation Complex Assembly, J. Biol. Chem. 275, 35006-35012 (2000). W. Ranatunga, J. Lebowitz, B. Axe, P. Pavlik, S. R. Kar & W. M. Scovell, Reexamination of the High Mobility Group-1 Protein For Self-Association and Characterization of Hydrodynamic Properties, Biochim. Biophys. Acta 1432, 1-12 (1999).
Joined the
faculty in 2005
Ph.D., S. I. Vavilov State Optical Inst, St. Petersburg, Russia (1993) M.S., Institute of Fine Optics, St. Petersburg, Russia (1986)
The focus of our
research interests is two-fold:
* Developing a molecular-level understanding of the dynamics of chemical reactions occurring in solution, and; * Gaining a deep, detailed insight into the dynamics and mechanisms of ultrafast (femto- and picosecond) photoinduced processes. In our research, we use state-of-the art experimental methods of ultrafast, time-resolved spectroscopy.
Visualizing Overdamped Wavepacket Motion: Excited-State Isomerization of Pseudocyanine in Viscous Solvents, Dietzek, B.; Tarnovsky, A.N.; Yartsev, A. Chem. Phys. 2009, 357, 54-62. Structure of the Photochemical Reaction Path Populated via Promotion of CF2I2 into Its First Excited State, El-Khoury, P. Z.; Tarnovsky, A. N.; Shapiro, I.; Ryazantsev, M. N.; Olivucci, M. J. Phys Chem. A, 2009, ASAP Article. Photochemistry of Iodoform in Methanol: The Formation and Fate of the Iso-CHI2-I Photoproduct, El-Khoury, P. Z.; Kwok, W. M.; Guan, X.; Ma, C.; Phillips, D. L.; Tarnovsky, A. N., ChemPhysChem. 2009, 10, 1895-1900. Photoaffinity Labeling via Nitrenium Ion Chemistry: Protonation of the Nitrene Derived from 4-Amino-3-nitrophenyl Azide to Afford Reactive Nitrenium Ion Pairs, Voskresenska, V.; Wilson, R. M.; Panov, M.; Tarnovsky, A. N.; Krause, J. A.; Vyas, S.; Winter, A. H.; Hadad, C. M., J. Am. Chem. Soc. 2009, 131, 11535-11547. The Effect of Dielectric friction on the Rate of Charge Separation in Type II ZnSe/CdS Semiconductor Nanorods, Hewa-Kasakarage, N. N.; El-Khoury, P. Z.; Schmall, N.; Kirsanova, M.; Nemchinov, A.; Tarnovsky, A. N.; Bezryadin, A.; Zamkov, M. App. Phys. Lett. 2009, 94, 133113.
Joined the faculty
in 2005
Ph.D., Massachusetts Institute of Technology (1965) B.S., The Pennsylvania State University (1961)
Our research
interests are directed towards photochemical application of lasers,
primarily argon ion lasers, and fall into two broad categories: the
laser synthesis of new materials and the development of reagents for
the photochemical manipulation of biological systems. These include:
* The use of CW laser plasmas to prepare carbon bowls, Bucky Bowls and the study of the properties of these bowl-shaped "aromatic" hydrocarbons. * The development of new reagents for the photochemical cross-linking of nucleic acids, primarily RNA, with proteins. * The development of new reagents for the photochemical cleavage of nucleic acids, primarily RNA. * The development of the aforementioned two techniques to study the interactions between nucleic acids and proteins using mass spectrometry to obtain detailed structural information about the nature of these interactions
"The Vocabulary of
Organic Chemistry", 2nd Edition, Wiley-Interscience, 2005, with Milton
Orchin, Allan Pinhas, and Roger Macomber.
"Photoaffinity Labeling with 8-Azidoadenosine and Its Derivatives: The Chemistry of Closed and Open Adenosine Diazaquinodimethanes", Biochemistry, 2005, 44, 11241-11253, with Dmitrii Polshakov, Saroj Rai, Eric T. Mack, Martin Vogel, Jeanette Krause, Gotard Burdzinski, and Matthew S. Platz. "DNA Photocleavage and Biological Activity of a Pyrene Dihydrodioxin", Bioorganic and Medicinal Chemistry Letters, 2005, 15, 2173-2176, with Eric T. Mack, Dagne Birzniece, Darren Veach, and William Coyle. "Thermal and Photochemistry of a Pyrene Dihydrodioxin (PDHD) and Its Radical Cation: A Photoactivated Masking Group for ortho-Quinones", Journal of the American Chemical Society, 2004, 126, 15324, with Eric T. Mack, A. Bjorn Carle, and J. T.-M. Liang, W. Coyle. |
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