Chemistry

Armin's research focuses on the effect of aerosol particles on the environment, clouds and rainfall, climate, and public health/welfare. A suite of synergistic methods are used for this research, including laboratory experiments, ground and airborne field measurements, modeling, and remote sensing observations. Since 2004, he has participated in 15 airborne field projects, including six as a mission PI with the CIRPAS Twin Otter (sponsored by ONR). Currently, Armin is involved with a multi-year NASA project called CAMP2EX (Cloud and Aerosol Monsoonal Processes-Philippines Experiment; https://espo.nasa.gov/camp2ex/content/CAMP2Ex) and is serving as the PI of a NASA Earth Venture Suborbital-3 (EVS-3) mission called ACTIVATE (Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment; https://activate.larc.nasa.gov/).

I am interested in exploring innovative and useful chemical tools and small molecules as probes to study biology and as therapeutics for disease treatment. My laboratory has been particularly interested in exploring chemical tools to address the important biological questions. I am a well-established investigator with over 20 years research experience and more than 240 peer reviewed publications (H-index: 72) in the fields of organic and medicinal chemistry and chemical biology. The small molecule-based fluorescence probes developed from my laboratory have been widely used by biomedical researchers as tools to study the cellular and molecular mechanisms. One of the small molecules discovered by my laboratory has been licensed to the Andaman Therapeutics for clinical trials as a new class of anticancer therapy.

Erin L. Ratcliff is an Assistant Professor of Materials Science and Engineering at the University of Arizona, with joint appointments in the Departments of Chemical and Environmental Engineering and Chemistry and Biochemistry. She also has a joint appointment with the National Renewable Energy Laboratory in Golden, CO. Dr. Ratcliff’s research group – the Laboratory for Interface Science of Printable Electronic Materials - is focused on the application of electrochemistry and spectroscopy to better understand the functionality of printable electronic materials, interfaces, and devices. The majority of her research efforts target understanding the structure-property relationships that govern charge transfer kinetics and transport of electronic and ionic species, with connections to energy conversion devices and biosensors.

Dr. Gerald (‘Gerry’) Maggiora, PhD, received a Bachelor of Science in chemistry and a PhD in biophysics from the University of California, Davis. He has more than 20 years experience in academia as a professor of chemistry and biochemistry at the University of Kansas, as well as five years as a professor in the College of Pharmacy at the University of Arizona. He has a comparable amount of experience in the pharmaceutical industry, where he served as the Director of Computer-Aided Drug Discovery for three different companies. His early work spanned numerous fields related to the development of quantum mechanical and molecular mechanics methods and their application to problems of mechanistic organic chemistry, vision, photosynthetic energy conversion, and the structural chemistry of drugs, biomolecules, and proteins. After joining the pharma industry, he directed his efforts towards the development and application of similarity and diversity methods and the analysis of biologically relevant chemical space to drug research. His recent work expands the concept of chemical space to include activity landscapes, which extend chemical spaces by including data on the activity of compounds in these spaces. This led to the notion of activity cliffs, which arise when two similar compounds exhibit significantly different activities, a phenomenon that runs counter to the well-known ‘Similarity-Property Principle’ that similar compounds tend to exhibit similar properties. Although relatively rare, activity cliffs provide significant information on structure-activity relationships that lie at the heart of drug design. He has also developed network-based representations of chemical space that circumvent many of the issues associated with the representation of these very high-dimensional spaces. He is currently continuing his work in this area. In recognition of his work in chemical informatics he received 2008 Herman Skolnik Award in Chemical Informatics presented by the Division of Chemical Information of the American Chemical Society.

Stephen Wright, PhD, is focused on understanding the molecular and cellular physiology of organic electrolyte transport in the kidney. The kidney, particularly the proximal tubule, actively secretes a wide array of organic ions, largely derived from dietary or pharmaceutical sources. Many of these compounds are toxic and renal secretion of these xenobiotic compounds plays a critical role in protecting the body from these agents. However, this task also places the kidney in harm's way, and the development of nephrotoxicity is one consequence of the renal secretion of what are typically referred to as organic anions and organic cations. Dr. Wright’s lab currently studies the renal transport of organic anions and cations at several different levels of biological organization.At the molecular level, they clone individual transport proteins for use in studies that gauge the effect of protein and substrate structure on the transport process. At the cellular level, Dr. Wright and his lab use cultured cells (including primary renal cells, continuous renal cell lines, and generic cells lines for the expression of cloned transport proteins) in studies of the activity and regulation of transport activity. At the tissue level, they use isolated, intact renal proximal tubules, including single non-perfused and perfused tubules, to study the process of organic electrolyte secretion as it occurs in the native renal epithelium.Studies employ a wide array of methodologies, including molecular cloning, site-directed mutagenesis, construction of fusion proteins, kinetic assessment of membrane transport in cultured cells, suspensions of isolated renal tubules and in single tubule segments using radiometric and real-time optical approaches, computationally-based assessment of transporter, and substrate structure and 3D distribution of cell type distribution along the renal nephron. Keywords: Membrane Transport; Kidney; Drug Clearance

Koen Visscher is an Associate Professor in the Department of Physics with an interest in Biological Physics. He holds joint appointments in Molecular and Cellular Biology as well as in the College of Optical Sciences, and is a member of the Applied Mathematics Graduate Interdisciplinary Program. His research focuses on the role of mechanical force in Biology using single-molecule techniques such as optical tweezers. He pioneered the so called molecular force clamp, a feedback controlled optical tweezers that is able to maintain a constant force on a single individual moving motor protein. Recent interests are RNA structure, nucleic acid-protein interactions interactions, and translational recoding via -1 frameshifting.

Mechanisms and pharmacology of acute and chronic models of pain; endogenous opioid systems; sensory neural systems; opioid tolerance; antinociceptive synergy between cannabinoids and opioids.

Josef Vagner, PhD, is an Associate Research Professor at the University of BIO5 Research Institute and the Director of the Ligand Discovery Laboratory. Dr. Vagner is expert in the field of drug discovery and development, and he is focused on the design, synthesis, purification, characterization and screening of compound arrays.He has published over 70 original research papers and 31 patents. He is a frequent presenter at national and international meetings (American Chemical Society and Peptide Societies).Dr. Vagner designed and developed of compounds for in vivo pharmacologic applications and translation programs. He has over 25 years experience in synthesis and structural analysis of de novo ligands for various biological targets, including a recent focus on ligands targeting GPCRs and multivalent ligands. These experiences include 10 years of work in the pharmaceutical industry (Sanofi/ Selectide, Novo Nordisk, Discovery Partner International) where he specialized in combinatorial chemistry and array synthesis of small molecules. During his time in industry, he supervised teams of workers who successfully accomplished the synthesis of more than ten large libraries (with >10,000 compounds each).

My research interests relate to the theoretical chemistry and biophysics of complex systems. Current areas of funded research include the study of protein dynamics in enzymatic reactions, quantum tunneling in enzymatic reactions, modeling of the cardiac thin filament with application to disease mechanism, and the study of the properties of micelles created from green surfactants. I am chair elect of the biological physics division of the American Physical Society, a Fellow of the APS and the AAAS.

Donato Romagnolo, MSc, PhD, has served as a member of study sections for the National Institutes of Health, the U.S. Department of Defense, the Susan G. Komen Breast Cancer Foundation, and as a scientific reviewer for nutritional, cancer, and pharmacology and toxicology scientific journals. Dr. Romagnolo is a member of the Training Grant in Cancer Biology at the University of Arizona. Dr. Romagnolo's research focuses on: 1) mechanisms of epigenetic silencing of tumor suppressor genes by environmental and dietary xenobiotics, and 2) role of dietary bioactive food components in the etiology and prevention of cancer and inflammation. For the last 14 years, Dr. Romagnolo's research has been funded by grants from the National Institutes of Health, the U.S. Army Department of Defense, the Susan G. Komen for the Cure and the Arizona Biomedical Research Commission.Some of his research reveals humans are exposed to a complex mixture of ligands of the aromatic hydrocarbon receptor (AhR). Prototypical AhR agonists include the polycyclic aromatic hydrocarbon (PAH) benzo[a]pyrene (B[a]P), and the dioxin-like compound 2,3,7,8 tetrachlorodibenzene(p)dioxin (TCDD). Increased incidence of breast cancer is documented in human populations of industrialized areas where high levels of dioxins are found in the air, soil, drinking water, and cow milk. Unlike PAH, TCDD is not metabolized and it promotes tumor development. Population studies reported the presence of TCDD in breast milk, suggesting this agent may accumulate in breast tissue and be a potential risk factor in mammary neoplasia. The in-utero activation of the AhR with TCDD increased the susceptibility to mammary carcinogens in rat female offspring. The activation of the AhR pathway may increase the susceptibility to breast cancer through epigenetic silencing of tumor suppressor genes, including p16 and p53, while inducing transcription of the proinflammatory COX-2 gene.