Kerri Scott, Instructional Professor, Associate Chair, & Associate Director of Forensic Chemistry

Instructional Professor
Associate Chair
Associate Coordinator of Forensic Chemistry

307 Coulter Hall
662-915-5334  |  kscott@olemiss.edu

EDUCATIONAL AND PROFESSIONAL BACKGROUND
B.S., Murray State University, 1988
M.S., Murray State University, 1989
D.A., The University of Mississippi, 2007

PROFESSIONAL RECOGNITION
National Academic Advising Association Outstanding Faculty Advisor
University of Mississippi Student Disability Student Services Access Award
Phi Eta Sigma National Honor Society
Mississippi Association of Nutrition and Dietetics Magnolia Award
University of Mississippi Excellence in Advising Award
Alpha Omicron Pi Women of Excellence
American Chemical Society Local Section Excellence in Faculty Advising and Mentorship

RESEARCH INTERESTS
Chemical education; undergraduate laboratory curriculum development; teaching strategies for large enrollment laboratory courses; secondary education teacher and teaching assistant training/development; online instruction; statistical studies of predictors for student success in chemistry courses.

Randy Wadkins, Professor of Chemistry & Biochemistry

Professor of Chemistry & Biochemistry

409 Coulter Hall
662-915-7732  |  rwadkins@ olemiss.edu

EDUCATIONAL AND PROFESSIONAL BACKGROUND
B.S., University of Mississippi, 1986
Ph.D., University of Mississippi, 1990
NIH Predoctoral Fellowship, University of Mississippi, 1986-1990
Max Plank Gesellschaft Postdoctoral Fellow, Max Planck Institute for Biophysical Chemistry, Goettingen, Germany, 1990-1991
Postdoctoral Fellowship, St. Jude Children’s Research Hospital, 1991-1994
AAAS S&T Congressional Fellow 2015-2016

PROFESSIONAL RECOGNITION
Biophysical Society Congressional Fellowship

RESEARCH INTERESTS
Biophysical chemistry, molecular dynamics, fluorescence microscopy and imaging, DNA structure and structural transitions, biosensors

RESEARCH SUMMARY
The primary focus of my lab is focused on developing improved antitumor drugs of the camptothecin family. Camptothecins are among the most promising new antitumor agents available. We are working on a “third generation” of camptothecins that are superior in activity to the clinically-used 2nd generation agents CPT-11 (Irinotecan) and topotecan (Hycamtin) just as these agents are superior to the parent camptothecin.

Fig. 1. The molecular structure of camptothecin

The 3rd generation of camptothecins are being tested for their ability to induce topoisomerase I-DNA complexes, and importantly, to induce temporally stable complexes. Camptothecins are specific topoisomerase I-targeting antitumor drugs. They are S-phase selective due to the need for DNA replication in their killing mechanism. However, camptothecins induce DNA damage in all phases of the cell cycle. We are developing analogs that can induce long-lasting DNA damage in G0/G1 phase of the cell cycle such that lethality ensues once these cells enter S-phase. Such analogs may be more effective in slow-growing tumors such as prostate and pancreas where there is presently no effective chemotherapeutic treatment. To develop these compounds, we are measuring the kinetics of dissociation of topoisomerase I from DNA as a function of chemical substitution on the camptothecin pharmacophore. This methodology reveals which substituents are able to induce long-lived complexes. We have recently demonstrated that the present 2nd generation of camptothecins may be limited in their activity because they form short-lived complexes. We use a variety of biophysical techniques to probe the interaction of camptothecins with topoisomerase I and DNA, including fluorescence imaging microscopy and temperature and osmotic pressure effects on rate constants for the dissociation of camptothecins from the topo I-DNA complex. We are now developing spectroscopic techniques to monitor drug, topoisomerase I, and DNA interactions in real (microsecond) time to characterize more clearly the way in which these drugs interact with their target. We have also recently determined that water participation is an important component of these interactions.

Figure 2: The active site of the B. subtilis enzyme that activates CPT-11. p-nitrophenylesterase

The second area of research in my laboratory is in the interface of experimental and computational chemistry. We have began using computational structural biology to interpret and predict experimental results in biochemistry. In collaboration with Dr. Philip Potter at St. Jude Children’s Research Hospital (Memphis, TN), we are currently using computational methods to understand the conversion of CPT-11 to SN-38 by liver carboxylesterases and how this process might be enhanced by selecting analogs of CPT-11 specific to selected carboxylesterases. The collaboration with Dr. Potter has identified a bacterial counterpart to the mammalian enzymes examined previously. The p-nitrophenylesterase from B. subtilis efficiently hydrolyzes CPT-11 and it can be readily mutated for analysis of specific residues that contribute to conversion of CPT-11. This enzyme has also been solved by x-ray crystallography. We are currently running molecular dynamics simulations of this enzyme and two mutants known to affect CPT-11 conversion by the enzyme. Hence, we have a unique opportunity to examine the molecular underpinnings of substrate selectivity across evolutionary divergence.

A third research interest is in DNA secondary structures as likely targets for drug development. Targeting drugs to select DNA sequences has been of interest to many investigators for years. However, in practice it is difficult to target long sequences of DNA due to the repetitive conformation of the DNA major and minor grooves. One way to target longer sequences of DNA is if these sequences adopt higher order (or “secondary”) structures, including DNA hairpins and their cousins the quadraplexes (or G-tetraplexes). Although these secondary structures were originally implicated in telomere maintenance, they have recently been demonstrated to have regulatory roles in the expression of a number of genes. These include transcription of β-casein, human platelet-derived growth factor, epidermal growth factor, c-myc, and human enkephalin. I have reviewed this topic in Wadkins (2000) Curr. Med. Chem. 7: 1-15. Figure 3: How small molecules may interfere with DNA secondary structures. In (A), duplex DNA may open spontaneously or may be opened by DNA-binding proteins to allow instigation of transcription. In (B), small DNA-binding molecules interfere with this process. DNA secondary structure Work from my colleagues Drs. Von Hoff and Laurence Hurley at the Arizona Cancer Center have recently demonstrated that c-myc can be effectively silenced by quadraplex-interactive drugs. This opens a great number of doors for the development of drugs that interact with these structures. At present, my lab is purifying a yeast transcription factor, RAP1, that is known to promote quadraplex formation in single-stranded DNA. Our goal is to use this factor to probe for quadraplex structure in a number of promoters for genes involved in cancer drug resistance, and to develop compounds that interfere with its binding. Further, following from the work of Craig Benham at UC-Davis, we are interested in how RAP1 may influence the ability of supercoiling in DNA to cause extrusion of these secondary structures.

The last area I am working in is the use of biosensing surfaces for the detection of cancer. Our work in this area has focused on the development of an implantable, optical fiber-based probe for detection of circulating tumor cells. Our sensor is based on a modified optical waveguide probe that detects signals from a fluorescent dye bound in proximity to its surface. Tumor cell attachment to the surface of the probe initiates a signal from the fluorescent dye that is detected by the device. This signal is then propagated to external electronics to indicate the presence of circulating tumor cells. The general description of such sensors is given in our review: Wadkins and Ligler (1998) Meth. Biotechnol. 7: 77. To construct the biosensor, we are developing a functionalized Polyethylene oxide (PEO)/Polystyrene (PS) surface that specifically binds cancer cells in vitro. We are producing an optical probe from the ligand-modified PEO/PS polymer that is suitable for implantation in the body. Finally, we are using this optical sensor for detecting and reporting binding of circulating cancer cells. Figure 4: Fiber optic biosensor

RECENT PUBLICATIONS
Complete citations for Randy M. Wadkins (link to NCBI database) Search for RM Wadkins

Gregory Tschumper, Professor of Chemistry & Biochemistry. Photo courtesy of Bella Vie Photography.

Professor

322 Coulter Hall
662-915-7301  |  tschumpr@olemiss.edu

EDUCATIONAL AND PROFESSIONAL BACKGROUND
B.S., Winona State University, 1995
Ph.D., University of Georgia, 1999
Postdoctoral Fellow, ETH Zürich, Switzerland, 1999-2000
Postdoctoral Fellow, Emory University, 2000-2001
Assistant Professor, University of Mississippi, 2001-2007
Associate Professor, University of Mississippi, 2007-2013
Professor, University of Mississippi, 2013-present
Chair, University of Mississippi Department of Chemistry & Biochemistry, 2016 – 2023

PROFESSIONAL RECOGNITION
Southeastern Conference (SEC) Faculty Achievement Award
Sigma Xi (The Scientific Research Honor Society) Member
University of Mississippi Faculty Achievement Award
Cora Lee Graham Award for Outstanding Teacher of Freshmen
University of Mississippi Faculty Research Fellow
Research Corporation Research Innovation Award
American Association for the Advancement of Science (AAAS) Fellow
University of Mississippi Distinguished Research and Creative Achievement Award

RESEARCH INTERESTS
physical chemistry, theoretical chemistry, computational chemistry, non-covalent interactions, hydrogen bonding, van der Waals forces

GROUP WEBPAGE

RESEARCH SUMMARY
My research group is devoted to obtaining answers and insight to important chemical problems in essentially every area of chemistry, especially biological and organic chemistry, through theory and computation rather than experimentation. Chemistry is largely governed by the physics of electrons. Because the quantum mechanical Schrodinger Equation, HΨ = EΨ, properly describes the physics of small objects such as electrons, its solutions can provide insight into the chemistry of atoms and molecules. Due to the complexity of the underlying mathematics, such solutions can only be obtained with substantial computational resources.

Of particular interest are weak chemical interactions (hydrogen bonding, van der Waals forces, pi-type interactions, etc.) that play a vital role in a host of chemical, physical, and biological processes. Using extremely accurate electronic structure techniques, we probe the details of the underlying physics behind these interactions. We are also developing new computational methods that can reliably describe weak chemical interactions in large chemical or biochemical systems.

RECENT PUBLICATIONS
See list of publications (with DOI links) at https://quantum.chem.olemiss.edu/pubs.html.

Instructor and Instrumentation Lab Manager

Liming Song-Cizdziel, Instructor and Instrumentation Lab Manager

332 Coulter Hall
662-915-2395  |  lsongcz@olemiss.edu

EDUCATIONAL AND PROFESSIONAL BACKGROUND
M.S., University of Reno, 1998
M.S., Nankai University, China, 1990
B.S. Nankai University, China, 1987

AREAS OF EXPERTISE
Biochemistry; analytical, environmental, and nutritional chemistry; chemistry education; natural product chemistry; dietary supplement research. Advanced analytical instrumentation methodologies, maintenance, and troubleshooting.

SUMMARY OF RESEARCH
Investigated active compounds in natural products for nutraceutical and therapeutic use. Identified, characterized and quantified natural products in plant materials using HPLC, LC/MS, GC/MS, TLC, NMR, Biotage and ASE.

Developed and validated methods for the analysis of wide varieties of natural products, including herbal products, vitamins, marine products, OTC drugs, and cosmetic products, using HPLC, GC, GC/MS, ICP, UV and FT-IR.

Jason Ritchie, Associate Professor of Chemistry & Biochemistry

Associate Professor of Chemistry & Biochemistry

309 Coulter Hall
662-915-5329  |  jritchie@olemiss.edu

EDUCATIONAL AND PROFESSIONAL BACKGROUND
B.S., University of California, San Diego, 1994
Ph.D., University of Texas at Austin, 1998
Postdoctoral Fellow, University of North Carolina, 1998-2000
Assistant Professor, The University of Mississippi, 2000-2006
Associate Professor, The University of Mississippi, 2006-present

RESEARCH INTERESTS
Synthesis of new polymeric electrolytes, structure conductivity relationships in polymeric electrolytes, proton exchange membrane (PEM) fuel cell electrolytes, solid lithium ion conducting polymer electrolytes

GROUP WEBPAGE

RESEARCH SUMMARY
My group seeks to understand how the molecular structure of an ion-conducting polymer affects its electrochemical properties. We are interested in creating and studying new materials that conduct Li+ and H+ cations for potential applications in lithium-ion batteries and proton exchange membrane (PEM) fuel cells. We are developing new methods of synthesizing electrolyte materials, and conducting experiments to elucidate the fundamental mechanisms of H+ and Li+ transport in these materials.

The potential applications of polymeric electrolyte materials designed for electrochemical power sources are huge. Unfortunately, only a few research groups are investigating new ways to prepare polymeric electrolytes. In order to realize the next generation of electrolyte materials, we need to develop new methods of materials synthesis. Many challenges remain unsolved in the field of polymer electrolytes, including finding new materials that display substantial anhydrous proton conductivity at elevated temperatures with reduced electroosmotic drag-induced fuel crossover.

We create our electrolytes by synthetically attaching an oligomeric mono-methyl polyethylene glycol (PEG) to a sol-gel polymerizable unit (Figure 1). The oligomeric PEG is a viscous liquid known for their ability to dissolve and conduct small cations. In addition, the PEG imparts disorder to the resulting polymer. While, there has been considerable effort in the sol-gel synthesis of new materials for fuel cells and batteries, most of the electrolyte work has centered on the synthesis of ceramic electrolytes for Solid Oxide Fuel Cells. The sol-gel synthesis of “soft” electrolytes (i.e. hybrid inorganic/organic systems) is virtually unexplored. My group focuses on the chemical tailoring of the properties of the electrolyte itself, in order to study the relationship between the electrolyte’s structure and electrochemical properties.

The first objective of this research is to elucidate the physical properties of the MePEG polymer that affect the observed electrochemical properties. In order to understand the physical properties of the MePEG polymer that lead to conductivity, we will:

develop reliable methods for the measurement of the MePEG polymer’s molecular weight and polydispersity index,
investigate the relationship between the MePEG polymer’s structure and conductivity properties, as a function of polymerization and branching,
determine the dependence of conductivity on structure by artificially altering the structure of the polymer,
examining thermal stability, and characterize glass transition temperatures (Tg) in these polymers to determine how segmental motions lead to Li+ transport and Grotthuss H+ transport.

We are seeking to gain a fundamental understanding of how the mechanism of proton conductivity contribute to ion transport in the MePEG polymer. Here, there are two general mechanisms for proton conductivity: the vehicle mechanism (which relies on the physical transport of a vehicle to move protons) and the Grotthuss mechanism (which involves the proton being handed off from one hydrogen bonding site to another). The Grotthuss mechanism is very similar to Li+ conductivity through segmental motions as it relies on the rate of polymer reorganization, while the vehicle mechanism is governed by the rate of physical diffusion of the vehicle. Understanding how molecules and ions travel through polymeric electrolytes is a fundamental question of great significance.

The second objective of this research is to understand the mechanism of cation conductivity and small molecule diffusion in the MePEG polymer. We hypothesize that both the Grotthuss mechanism and the vehicle mechanism for proton conductivity are operating in mixtures of MePEG7SO3H and the MePEG polymer. To understand the fundamental mechanism of conductivity, we will:

use isotopic and ionic substitution to determine the contribution of the Grotthuss mechanism in these electrolytes
probe the vehicle mechanism of conductivity by comparing the conductivity and activation barriers with different sized vehicles
correlate the viscosity of the MePEG polymer with the physical diffusion of small redox active molecules
understand how the structural details of the polymer affect the susceptibility to electroosmotic drag of small redox active molecules

My co-workers will receive a broad exposure to the fields of electrochemistry and solid-state inorganic chemistry. This broad, inter-disciplinary training will prepare students in my group for a successful career in industry or academia. Students in my laboratory will become familiar with many different analytical techniques common to solid-state chemistry, inorganic chemistry, and electrochemistry. Some of the techniques that we commonly perform include chemical reactions under inert-atmosphere conditions using standard Schlenk techniques, solid-state synthetic reactions, and electrochemical and conductivity experiments.

Meet my research group

Jason’s Homepage

Jason’s Curriculum Vitae

Jason Ritchie’s Teaching Portfolio

RECENT PUBLICATIONS
Jason E. Ritchie (2006) “Electronic and Electrochemical Applications of Hybrid Materials”, in Hybrid Materials: Synthesis, Characterization, and Applications; edited by Guido Kickelbick, Wiley-VCH, published December 2006 (Book Link)

Braja D. Ghosh, Kyle F. Lott, Jason E. Ritchie (2006) “Structural Characterization of a Sol-Gel prepared Anhydrous Proton Conducting Electrolyte”, Chemistry of Materials, 18(2), 504-509 (Article Link, Free Reprint)

Kyle F. Lott, Braja D. Ghosh, Jason E. Ritchie (2006) “Understanding the Mechanism of Ionic Conductivity in an Anhydrous Proton Conducting Electrolyte through Measurements of Single-ion Diffusion Coefficients”, Journal of the Electrochemical Society, 153 (11), A2044-2048 (Article Link)

Braja D. Ghosh, Kyle F. Lott, Jason E. Ritchie (2005) “Conductivity Dependence of PEG Content in an Anhydrous Proton Conducting Sol-Gel Electrolyte”, Chemistry of Materials; 17, 661-669 (Article Link, Free Reprint)

Kyle F. Lott, Braja Ghosh, Jason E. Ritchie (2005) “Measurement of Anion Diffusion and Transference Numbers in an Anhydrous Proton Conducting Electrolyte”, Electrochemical and Solid-State Letters; 8(10), A513-A515 (Article Link)

Jason E. Ritchie and Jeffrey A. Crisp (2003) “A Sol-Gel Synthesis of Polyether Based Proton Conducting Electrolytes”, Analytica Chimica Acta; 496, 65-71 (Article Link)

Susan Pedigo, Professor of Chemistry and Biochemistry

Professor of Chemistry & Biochemistry

405 Coulter Hall
662-915-5328  |  spedigo@olemiss.edu

GROUP WEBPAGE

EDUCATIONAL AND PROFESSIONAL BACKGROUND
B.A., University of Colorado, 1982
M.S., University of Minnesota, 1987
Ph.D., University of Iowa, 1995
Biocatalysis Predoctoral Fellowship, Center for Biocatalysis and Bioprocessing, 1993
Postdoctoral Scientist, Vanderbilt University, Department of Molecular Biology, 1995-1998

PROFESSIONAL RECOGNITION
College of Liberal Arts Outstanding Teacher of the Year

RESEARCH INTERESTS
Biochemistry, stability, calcium binding and dimerization of cadherins

RESEARCH SUMMARY
Calcium-dependent Assembly of Cadherins
Cadherins are transmembrane proteins that are responsible for communication between identical cells through calcium-dependent interactions. Members of this family are named according to the cell type in which they predominate. Type I or classical cadherins (e.g. E- and N-cadherins) have a common domain organization. The N-terminal extracellular region has 5 independently folded modular domains connected in series according to primary sequence (Figure 1A). These ectodomains are anchored to the cell surface by a transmembrane segment, and organized spatially on the cell surface by a cytoplasmic domain that is connected indirectly to the actin cytoskeleton by catenins. Cadherins on the same cell surface can self-associate into cis-dimers (lateral dimers). The basis of adhesion is interactions between identical cadherins on neighboring cell surfaces to form trans-dimers (adhesive dimers; see Figure 1B). In spite of concerted effort by many research teams, there is still ambiguity about the structural nature of the lateral and adhesive interfaces.

Figure 1 (A) Modular structure of ectodomains. Each ectodomain is a 7-strand (A to G) beta-barrel structure Domains are numbered 1-5 from the N-terminal domain to the most membrane proximal domain. Calcium binds at the interface between domains (black circles). Constructs studied in this proposal contain Domains 1 and 2 of Neural-cadherin with the adjoining linker segments (NCAD12). (B) Lateral and adhesive interactions. Blue ovals represent the ectodomain modules with “lateral” interactions (green star) between cadherins from the same cell surface and “adhesive” interactions (red star) between cadherins from opposing cell surfaces.

Recently cell-cell interaction studies and high resolution structural studies have converged on a model that proposes the following: 1. Calcium binding induces conformational change in Domain 1 leading to detachment of the A-strand. This is a conformational transition from a “Closed” to an “Open” state. 2. The “Open” state forms a strand-crossover that is the adhesive dimer interface. A schematic diagram of the linkage between calcium binding, conformational change and dimerization is shown in Figure 2. Detailed calcium-binding studies from our lab elaborate this model to propose that binding of Ca3 generates the conformational change. This field has now matured to the point where biophysical techniques can be used to test the role of specific amino acids in the equilibria that culminate with formation of the adhesive dimer. The overall goal of our research is to understand the molecular mechanism that leads to adhesion in classical cadherins through studies of the linked equilibria in Figure 2. We use thermodynamic approaches to monitor the stability, calcium binding and assembly of the extracellular domains of cadherins.

Current Research Projects test the following hypotheses: 1. Ca3 is the primary player in the physical linkage between Domains 1 and 2 and in the conformational transition from the “Closed” to the “Open” state. 2. The “Opening” of the A-strand requires the undocking of W2 from the hydrophobic pocket. 3. The adhesive structure is a strand crossover structure. 4. Calcium binding modifies the kinetics of assembly and disassembly of the strand crossover species.

RECENT PUBLICATIONS
Mallela, J.; Perkins, R.; Yang, J.; Pedigo, S.; Rimoldi, J. M.; Shariat-Madar, Z., The functional importance of the N-terminal region of human prolylcarboxypeptidase. Biochemical and Biophysical Research Communications 2008, 374, 635-640.

Prasad, A.; Zhao, H. Y.; Rutherford, J. M.; Housley, N.; Nichols, C.; Pedigo, S., Effect of linker segments on the stability of epithelial cadherin domain 2. Proteins-Structure Function and Bioinformatics 2006, 62, 111-121.

Prasad, A. and Pedigo, S. “Stability of Extracellular Domains 1 and 2 of Epithelial-Cadherin” Biochemistry 2005, 44:13692-13701.

Hobson, K. F., Housley, N. A. and Pedigo, S. “Ligand-linked stability of mutants of the C-domain of calmodulin” Biophysical Chemistry 2005, 114 (1): 43-52.

Prasad, A., Housley, N. A. and Pedigo, S. “Thermodynamic Stability of Domain 2 of Epithelial Cadherin” Biochemistry 2004, 43: 8055-8066.

Michael Mossing, Associate Professor of Chemistry

Associate Professor of Chemistry & Biochemistry Emeritus

452 Coulter Hall
662-915-5339  |  mmossing@olemiss.edu

EDUCATIONAL AND PROFESSIONAL BACKGROUND
B.S, Michigan State University, 1980
Ph.D., University of Wisconsin, 1985
Postdoctoral Fellow, Massachusetts Institute of Technology, 1986-1990

RESEARCH INTERESTS
Biophysical chemistry; DNA binding protein structure and function; combinatorial mutagenesis; protein engineering and expression; circular dichroism, fluorescence, and NMR spectroscopy; thermodynamics and kinetics of protein folding and macromolecular recognition; the coupling of protein folding and assembly to DNA recognition

GROUP WEBPAGE

RESEARCH SUMMARY
Proteins bind to specific DNA sites and to each other to control gene expression. These regulatory complexes direct the construction and maintenance of cells and organisms from their genomic blueprints. Genetics and molecular biology give us the tools to identify transcriptional regulatory proteins and their DNA binding sites and map out the control circuits that drive living systems. Structural biology enables the examination of these proteins and their complexes with DNA in atomic detail. Work in my laboratory is aimed at characterizing the thermodynamic and kinetic properties of these protein-DNA interactions. The conditions under which we can make biochemical measurements on purified components in the laboratory are often far removed from the crowded, complex microcosm of a living cell. In order to verify our extrapolations we make measurements under various solution conditions and on proteins and DNA sites that have been engineered or manipulated to test specific hypotheses. The ultimate test of our success will be in developing mathematical models that describe the behavior not only of natural regulatory systems but systems built from modified components that have been characterized in vitro.

Cro folding and dimer assembly are coupled to DNA recognition The Cro repressor of bacteriophage lambda is one of the simplest and best characterized of any DNA binding protein. It helps to control a simple binary genetic switch that toggles between two lifestyles for bacteriophage lambda and the life or death of lambda’s bacterial host. We have shown that a major limitation in Cro’s ability to bind to DNA is in the formation of the protein dimers that are necessary for DNA binding. Studies of the kinetics and thermodynamics of protein folding and dimer assembly are ongoing. Engineered variants of Cro that are trapped either in the dimeric state or the monomeric state or that fold at different rates and assemble to different extents will will help in completing our understanding of this simple genetic circuit.

RECENT PUBLICATIONS
Maity H, Mossing MC, Eftink MR. Equilibrium unfolding of dimeric and engineered monomeric forms of lambda Cro (F58W) repressor and the effect of added salts: evidence for the formation of folded monomer induced by sodium perchlorate. Arch Biochem Biophys. Feb 1;434(1):93-107.

Jia H, Satumba WJ, Bidwell GL 3rd, Mossing MC. Slow assembly and disassembly of lambda Cro repressor dimers. J Mol Biol. Jul 29;350(5):919-29.

Mollah AK, Stennis RL, Mossing MC. Stability of monomeric Cro variants: Isoenergetic transformation of a type I’ to a type II’ beta-hairpin by single amino acid replacements. Protein Sci. 2003 May;12(5):1126-30.

4: Satumba WJ, Mossing MC. Folding and assembly of lambda Cro repressor dimers are kinetically limited by proline isomerization. Biochemistry. Dec 3;41(48):14216-24.

Daniell Mattern, Professor of Chemistry

Professor of Chemistry & Biochemistry

411 Coulter Hall
662-915-5335  |  mattern@olemiss.edu

EDUCATIONAL AND PROFESSIONAL BACKGROUND
B.A., Kalamazoo College, 1970
M.S., Stanford University, 1971
Ph.D., Stanford University, 1975
Postdoctoral Fellow, Tufts University School of Medicine, 1976
Postdoctoral Fellow, University of California at San Diego, 1977-1979

PROFESSIONAL RECOGNITION
Elsie M. Hood Outstanding Teacher Award
College of Liberal Arts Outstanding Teacher of the Year
Alpha Epsilon Delta Outstanding Teacher of the Year
University of Mississippi 25-Year Service Award
Margaret McLean Coulter Professor of Chemistry

RESEARCH INTERESTS
Organic Donor-sigma-Acceptor molecules, fatty acyl analogs of acarnidine, aromatic iodination

RESEARCH SUMMARY
Organic donor-sigma-acceptor molecules. The goal of this project is to prepare compounds containing electron- donor and electron-acceptor groups, separated by a bridge of non-conducting sigma bonds. Each “D-sigma-A” target also typically contains pendant lipid tail(s) to help the molecules assemble as an ordered Langmuir-Blodgett film, or pendant alkyl thiol(s), sulifde(s), or disulfide(s) to help them assemble as an ordered monolayer on a gold surface. Such films may serve to rectify electrical current in molecule-sized circuits, which could lead to tiny electrical devices. In fact, one of our products, utilizing a pyrene donor group and a dinitrobenzyl acceptor group, displays striking rectifying voltage properties when tested as a multilayer. Our current work involves (1) making new D-sigma-A targets via further elaboration of the good donor pyrene; (2) forming the sigma bridge via Diels Alder reactions between donor-dienes and acceptor-dienophiles; (3) using anhydride chemistry to attach sigma-A and solublizing groups at opposite ends of the annoyingly insoluble compound perylene, which can potentially be converted to either a good donor or a good acceptor; and (4) attaching three thiol tails to model donor molecules in such a way that their orientation on gold electrodes will be forced to be orthogonal.

Aromatic iodination. This work investigates the direct substitution of many iodine atoms onto aromatic rings. We have developed a powerful system (I2 / H4IO6 / H2SO4) for iodinating deactivated aromatics. For example, nitrobenzene and benzoic acid can easily be pentaiodinated. However, the method fails for activated rings; the conditions are too harsh. Our future work involves moderating the reaction conditions to promote high-yield conversions in activated systems such as phenol and the xylenes. Careful 13C-NMR analysis is crucial for this work, as the iodinated products have few protons for 1H-NMR, have few functional groups for IR analysis, and have high molecular weights making mass spectrometry difficult. The iodinated products have become valuable synthetic intermediates as the use of palladium-catalyzed coupling reactions of iodoorganics with alkenes (the Heck reaction) and organotins (the Stille reaction) has grown.

PushMaster Dr. Mattern is the author of the PushMasterTM electron-pushing skill-builder computer program. PushMaster runs as a HyperStudio multimedia program with the (free) HyperStudio Player. It provides patient and, most importantly, interactive practice in the crucial skill of “pushing electrons” for the understanding of fundamental organic chemistry mechanisms and reactions. PushMaster is currently available on the University of Mississippi campus for the Macintosh platform.

RECENT PUBLICATIONS

Chen, W.-Y.; Mattern, D.L.; Okinedo, E.; Senter, J. C.;  Mattei, A. A.; Redwine, C. W. “Photochemical and Acoustic Interactions of Biochar with CO₂and H₂O: Applications in Power Generation and CO₂Capture” AIChE Journal 2014, 60, 1054-1065. DOI 10.1002/aic.14347

Yu, D.; Mattern, D.L.; Forman, B.M. An improved synthesis of 6α-ethylchenodeoxycholic acid (6ECDCA), a potent and selective agonist for the Farnesoid X Receptor (FXR) Steroids 2012, 77, 1335-1338. DOI:10.1016/j.steroids.2012.09.002

Kota, R.; Samudrala, R.; Mattern, D.L. Synthesis of Donor-σ-Perylenebisimide-Acceptor Molecules Having PEG Swallowtails and Sulfur Anchors. Journal of Organic Chemistry 2012, 77, 9641-9651. DOI:10.1021/jo301701a

Scardino, D.J.; Kota, R.; Mattern, D.L.; Hammer, N.I. Single molecule spectroscopic studies of organic rectifiers composed of pyrene and perylenebisimide. Chemical Physics Letters 2012, 550, 138-145. DOI:10.1016/j.cplett.2012.09.008

Metzger, R.M.; Mattern, D.L. Unimolecular Electronic Devices. “Topics in Current Chemistry.” 2012, 313 (Unimolecular and Supramolecular Electronics II), 39-84. DOI:10.1007/128_2011_178

Jupally, V.R.; Kota, R.; Van Dornshuld, E.; Mattern, D.L.; Tschumper, G.S.; Jiang, D.; Dass, A. Interstaple Dithiol Cross-Linking in Au₂₅(SR)₁₈ Nanomolecules: A Combined Mass Spectrometric and Computational Study. Journal of the American Chemical Society 2011, 133, 20258-20266. DOI:10.1021/ja206436x

Hong, Y.-S.; Boo, W.O.J.; Mattern, D.L. Magnetic properties of linear trimers in fluoride analogs of tetragonal tungsten bronze. Journal of Solid State Chemistry 2010, 183, 1805-1810. DOI:10.1016/j.jssc.2010.05.030.

Boo, W.O.J.; Mattern, D.L. Concomitant Ordering and Symmetry Lowering The Journal of Chemical Education. 2008, 85, 710-717.

Samudrala, R.; Zhang, X.; Wadkins, R. M.; Mattern, D. L. Synthesis of a Non-Cationic, Water-Soluble Perylenetetracarboxylic Diimide and Its Interactions with G-Quadruplex-Forming DNA. Bioorganic & Medicinal Chemistry 2007, 15, 186-193. doi:10.1016/j.bmc.2006.09.075.

Shumate, W.J.; Mattern, D.L.; Jaiswal, A.; Dixon, D.A.; White, T.R.; Burgess, J.; Honciuc, A.; Metzger, R.M. Spectroscopy and rectification of three Donor-Sigma-Acceptor compounds, consisting of a one-electron donor (pyrene or ferrocene), a one-electron acceptor (perylenebisimide), and a C19 swallowtail. Journal of Physical Chemistry B 2006, 110, 11146-11159.

Davis, S.R.; Nguyen, K.A.; Lammertsma, K.; Mattern, D.L.; Walker, J.E. Ab initio Study of the Thermal Isomerization of Tricyclo[3.1.0.02,6]hexane to (Z,Z)-1,3 Cyclohexadiene through the (E,Z)-1,3-Cyclohexadiene Intermediate. Journal of Physical Chemistry A, 2003; 107; 198-203.

Wescott, L.D.; Mattern, D.L. Donor-Sigma-Acceptor Molecules Incorporating a Nonadecyl-Swallowtailed Perylenediimide Acceptor. Journal of Organic Chemistry 2003 ,68 , 10058-10066.

Boo, W.O.J.; Mattern, D.L. Generating Closed Shapes from Regular Tilings. Journal of Chemical Education 2002, 79, 1017-1023 (cover article).

Hu, Jian; Mattern, D.L. Ferrocenyl Derivatives with One, Two, or Three Sulfur Containing Arms for Self Assembled Monolayer Formation. Journal of Organic Chemistry, 2000, 65, 2277-2281.

Yu, Duyi; Mattern, D.L. “Preparation of the three 2,3-dihalo-1,4-benzoquinones.” Synthetic Communications, 1999.

Brady, A.C.; Hodder, B.; Martin, A.S.; Sambles, J.R.; Ewels, C.P.; Jones, R.; Briddon, P.R.; Musa, A.M.; Panetta, C.A.; Mattern, D.L. Molecular rectification with M | (D-sigma-A LB film) | M junctions. Journal of Materials Chemistry, 1999, 9, 2271-2275.

Lee, H.; He, Z.; Hussey, C.L.; Mattern, D.L. Chem. Mater. 1998, 10, 4148. “Unsymmetrical Dialkyl Sulfides for Self-Assembled Monolayer Formation on Gold: Lack of Preferential Cleavage of Allyl or Benzyl Substituents.”

Mattern, D.L.; Scott, W.D.; McDaniel, C.A.; Weldon, P.J.; Graves, D.E. J. Nat. Prod., 1997, 60, 828-831. “Cembrene and a congeneric ketone isolated from the paracloacal gland of the Chinese alligator (Alligator sinensis).”

Musa, A.; Sridharan, B.; Lee, H.-Y.; Mattern, D.L. J. Org. Chem. 1996, 61, 5481-5484. “7 Amino-2-pyrenecarboxylic Acid.”

Panetta, C.A.; Fang, Z.; Mattern, D.L. J. Org. Chem. 1995, 60, 7953-7958. “Iodination of methylated anisoles: unusual aryl methyl replacements and oxidations.”

Mattern, D.L. J. Chem. Educ. 1995, 72, 1092. “Elemental Anagrams Revisited. ”

Nadizadeh, H.; Mattern, D.L.; Singleton, J.; Wu, X.-L.; Metzger, R.M. Chem. Mater. 1994, 6, 268-277. “Langmuir-Blodgett films of Donor-sigma-Acceptor (D-sigma-A) compounds, where D = anilide donors with internal diyne or saturated lipid tails, sigma = carbamate bridge, and A = 4-nitrophenyl or TCNQ acceptors.”

Heimer, N.E.; Mattern, D.L. J. Am. Chem. Soc. 1993, 115, 2217-2220. “A structural steric isotope effect in deuterated tetracyanoanthraquinodimethane.

Mattern, D.L.; Chen, X. J. Org. Chem. 1991, 56, 5903-5907. “Direct polyiodination of benzenesulfonic acid.”

Metzger, R.M.; Wiser, D.C.; Laidlaw, R.K.; Takassi, M.A.; Mattern, D.L.; Panetta, C.A. Langmuir 1990, 6, 350-357. “Monolayers and Z-type multilayers of donor-sigma-acceptor molecules with one, two, and three dodecoxy tails.”

Charles L. Hussey, Distinguished Professor and Fellow of The Electrochemical Society

Associate Dean Emeritus for Research & Graduate Education and Distinguished Professor Emeritus of Chemistry and Biochemistry

Fellow of The Electrochemical Society

Max Bredig Award in Molten Salt and Ionic Liquid Chemistry

2014 R&D 100 Award

Technical Editor, The Electrochemical Society Journals

413 Coulter Hall | chclh@olemiss.edu
662-915-5333

EDUCATIONAL AND PROFESSIONAL BACKGROUND
B.S., University of Mississippi, 1971
Ph.D., University of Mississippi, 1974
Research Chemist, Frank J. Seiler Research Lab, United States Air Force Academy, 1974-1978
Chair, Department of Chemistry and Biochemistry, University of Mississippi, 1998-2016

PROFESSIONAL RECOGNITION
“Lift Every Voice Award” for Diversity and Inclusion, Black History Month 2018
Fellow of the Electrochemical Society
Electrochemical Society Max Bredig Award in Molten Salt and Ionic liquid Chemistry
R&D Magazine 100 Award
Southeastern Conference Faculty Achievement Award
University of Mississippi Faculty Achievement Award
University of Mississippi Distinguished Research and Creative Achievement Award
University of Mississippi 25-Year Service Award

RESEARCH INTERESTS
Electrochemistry and transport properties of room-temperature ionic liquids, especially chloroaluminates; electrodeposition of metal and alloy films; transition metal electrochemistry; electrochemical processing of spent nuclear fuel and radioactive fuel-processing waste

RESEARCH SUMMARY
Our current research efforts are directed at the electrochemistry and transport properties of a variety of room-temperature ionic liquids. Two classes of these ionic solvents that are of particular interest are the organic chloroaluminates with adjustable Lewis acidity, such as aluminum chloride-1-ethyl-3-methylimidazolium chloride, and inert hydrophobic ionic liquids such as tri-1-butylmethylammonium bis((trifluoromethane)sulfonyl)imide. Projects under investigation include electrochemical processing of spent nuclear fuel components, electrodeposition of corrosion-resistant, non-equilibrium aluminum-transition metal alloys, and measurement of the heterogeneous kinetics of outer-sphere redox couples in highly viscous ionic liquid solutions.

RECENT PUBLICATIONS

L.-H. Chou, A. Kurachi, Y. Pan, and C. L. Hussey, “Thermodynamics and Electron Transfer Kinetics of the [CeCl₆]^2-/3- Electrode Reaction in a Series of Bis(trifluoromethyl-sulfonyl)imide-Based Room Temperature Ionic Liquids,” ACS Sustainable Chemistry and Engineering, 7, 3454-3463 (2019) DOI: 10.1021/acssuschemeng.8b05666.

C.-Y. Chen, T. Tsuda, S. Kuwabata, and C. L. Hussey, “Rechargeable Aluminum Batteries Utilizing a Chloroaluminate Inorganic Liquid Electrolyte,” Journal of the Chemical Society, Chemical Communications, 54, 4164-4167 (2018), DOI:10.1039/C8CC00113H. [invited as part of the themed collection on Ionic Liquids in the Synthesis, Fabrication, and Utilization of Materials and Devices]

S. Johnson, C. Hutchison, C. Williams, C. Hussey, G. Tschumper, and N. Hammer, Intermolecular Interactions and Vibrational Perturbations within Mixtures of 1-Ethyl-3-methylimidazolium Thiocyanate and Water,” Journal of Physical Chemistry C, (2018), DOI: 10.1021/acs.jpcc.8b07114.

T. Tsuda, G. R. Stafford, and C. L. Hussey, “Electrochemical Surface Finishing and Energy Storage Technology with Room-Temperature Haloaluminate Ionic liquids and Mixtures,” J. Electrochem. Soc., 164, H5007-H5017 (2017).   DOI:10.1149/2.0021708jes.   JES Focus Issue on Progress in Molten Salts and Ionic Liquids.

Tetsuya Tsuda, Chih-Yao Chen, and Charles L. Hussey, “Novel Analytical Techniques for Smart Ionic Liquid Materials,” Chapter 1 in Ionic Liquid Devices, Ali Ektekhari, Ed., Royal Society of Chemistry Book Series, pp 1-29 (2017). DOI:10.1039/9781788011839-00001.

C. Wang, A. Creuziger, G. Stafford, and C. L. Hussey, “Anodic Dissolution of Aluminum in the Aluminum Chloride-1-Ethyl-3-methylimidazolium Chloride Ionic Liquid,” J. Electrochem. Soc., 163, H1186-H1194 (2016). DOI: 10.1149/2.1061614jes.

C. Wang and C. L. Hussey, “Aluminum Anodization in the LiAlBr₄-NaAlCl₄-KAlCl₄ Molten Salt,” J. Electrochem. Soc., 162, H151-H156 (2015). DOI:10.1149/2.0591503jes.

T. Tsuda, Y. Ikeda, A. Imanishi, S. Kusumoto, S. Kuwabata, G. R. Stafford, and C. L. Hussey, “Electrodeposition of Al-W-Mn Ternary Alloys from the Lewis Acidic Aluminum Chloride-1-Ethyl-3-methylimidazolium Chloride Ionic Liquid,” J. Electrochem. Soc., 162, D405-D411 (2015). DOI:10.1149/2.0051509jes.

T. Tsuda, Y. Ikeda, T. Arimura, M. Hirogaki, A. Imanishi, S. Kuwabata, W. E. Cleland, Jr., G. R. Stafford, and C. L. Hussey, “Electrodeposition of Al-W Alloys in the Lewis Acidic Aluminum Chloride−1-Ethyl-3-Methylimidazolium Chloride Ionic Liquid,” J. Electrochem. Soc., 161, D405-D412 (2014), DOI:10.1149/2.016409jes.

L. H. Chou and C. L. Hussey, “An Electrochemical and Spectroscopic Study of Nd(III) and Pr(III) Coordination in the 1-Butyl-3-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide Ionic Liquid Containing Chloride Ion,” Inorg. Chem., 53, 5750-5758 (2014). DOI: 10.1021/ic5005616.

Y. Pan and C. L. Hussey, “An Electrochemical and Spectroscopic Investigation of Ln³⁺ (Ln = Sm, Eu, and Yb) Solvation in Bis(trifluoromethylsulfonyl)imide-based Ionic Liquids and Coordination by N,N,N’,N’-tetraoctyl-3-oxa-pentane Diamide (TODGA) and Chloride,” Inorg. Chem., 52, 3241-3252 (2013). DOI: 10.1021/ic3027557.

T. Tsuda, S. Kuwabata, G. R. Stafford, and C. L.Hussey, “Electrodeposition of Aluminum-Hafnium Alloys from the Lewis Acidic Aluminum Chloride-1-Ethyl-3-methylimidazolium Chloride Molten Salt,” J. Solid State Electrochem., 17, 409-417 (2013). DOI: 10.1007/s10008-012-1933-y.

L.-H. Chou, W. E. Cleland, Jr., and C. L. Hussey, “An Electrochemical and Spectroscopic Study of Ce(III) Coordination in the 1-Butyl-3-methylpyrrolidinium Bis(trifluoromethyl­sulfonyl)imide Ionic Liquid Containing Chloride Ion,” Inorg. Chem., 51, 11450-11457(2012). DOI: 10.1021/ic301172g

H. Y. Lee, J. B. Issa, S. S. Isied, E. W. Castner, Jr., Y. Pan, C. L. Hussey, K. S. Lee, and J. F. Wishart, “A Comparison of Electron Transfer Dynamics in Ionic Liquids and Neutral Solvents,” J. Phys. Chem. C, 116(8), 5197-5208 (2012). DOI: 10.1021/jp208852r

Y. Pan, W. E. Cleland, Jr., and C. L. Hussey, “Heterogeneous Electron Transfer Kinetics and Diffusion of Ferrocene/Ferrocenium in Bis(trifluoromethylsulfonyl)imide-Based Ionic Liquids,” J. Electrochem. Soc., 159, F1-F9 (2012). DOI: 10.1149/2.054205jes

Y. Pan, L. E. Boyd, J. F. Kruplak, W. E. Cleland, Jr., J. S. Wilkes, and C. L. Hussey, “Physical and Transport Properties of Bis(trifluoromethylsulfonyl)imide-Based Room-Temperature Ionic Liquids: Application to the Diffusion of Tris(2,2’-bipyridyl)ruthenium(II),” J. Electrochem. Soc., 158, F1-F9 (2011). DOI: 10.1149/1.3505006

T. Tsuda, K. Kondo, T. Tomioka, Y. Takahashi, H. Matsumoto, S. Kuwabata, and C. L. Hussey, “Design, Synthesis, and Electrochemistry of Room-Temperature Ionic Liquids Functionalized with Propylene Carbonate,” Angew. Chem. Intl. Ed., 50, 1310-1313 (2010). DOI: 10.1002/anie.201005208