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This lecture series commemorates Professor Dawson's leadership in the Department and features speakers noted for the quality, depth and breadth of their research.

Jeffrey Moore received his B.S. in chemistry (1984) and Ph.D. in materials science and engineering with Samuel Stupp (1989), both from the University of Illinois. He then went to Caltech as a National Science Foundation Postdoctoral Fellow working with Robert Grubbs. In 1990, he joined the faculty at the University of Michigan in Ann Arbor and in 1993 returned to the University of Illinois, where he was Professor of ����vlog�ٷ����, as well as a Professor of Materials Science & Engineering until 2022 and was also selected as the Stanley O. Ikenberry Endowed Chair in 2018. Jeff is a member of the National Academy of Sciences and a fellow of the American Academy of Arts & Sciences, the American Association for the Advancement of Science and the American Chemical Society (ACS); he has received the Campus Award for Excellence in Undergraduate Teaching and has been recognized as a “Faculty Ranked Excellent by their Students.”

For 14 years he served as an associate editor for the Journal of American Chemical Society. In 2014, he was selected as a Howard Hughes Medical Institute Professor and in 2016 was chosen as the recipient for the ACS Edward Leete Award in Organic ����vlog�ٷ����. He received the Royal Society of ����vlog�ٷ����’s Materials ����vlog�ٷ���� Division 2018 Stephanie L. Kwolek Award and was part of a team that was honored with the Secretary of Energy Honor Award, Achievement Award the same year. Jeff was also awarded the 2019 National Award in Polymer ����vlog�ٷ���� by the American Chemical Society. He has published over 400 articles covering topics from technology in the classroom to self-healing polymers, mechanoresponsive materials and shape-persistent macrocycles. He served as the Director of the Beckman Institute for Advanced Science and Technology at the University of Illinois from 2017-2022. In this role, he received the 2021 Executive Officer Distinguished Leadership Award from the UIUC Campus.

"Polymeric Materials for Lifecycle Control"

In this talk I will discuss the molecular design of organic structural materials that mimic living systems’ abilities to protect, report, heal and even regenerate themselves in response to damage, with the goal of increasing lifetime, safety and sustainability of many manufactured items. I will emphasize recent developments in frontal ring-opening metathesis polymerization (FROMP)to manufacture composites with minimal energy consumption. The talk will conclude by introducing the idea of morphogenic manufacturing in which we aim to achieve symmetry breaking in neat polymerization reactions through a coupled reaction-diffuse process; the longterm vision is self-patterned form and function in synthetic materials.

References:

1. Patrick, J.F.; Robb, M.J.; Sottos, N.R.; Moore, J.S.; White, S.R. Polymers with Autonomous Life-cycle Control, Nature, 2016, 540, 363-370.

2. Robertson, I.D.; Yourdkhani, M.; Centellas, P.J.; Aw, J.; Ivanoff, D.G.; Goli, E.; Lloyd. E.M.; Dean, L.M.; Sottos, N.R.; Geubelle, P.H.; Moore, J.S.; White, S.R. Rapid Energy-efficient

Abstract: The biosynthesis of both fatty acids and polyketides involves a common reaction, the iterative carbon-carbon bond formation between acyl-thioesters and malonyl-thioesters. While fatty acids and polyketides are essential to society for a plethorea of reasons, how the underlying carbon-carbon bond forming reactions occur remains an open question. Malonyl-thioesters are akin to biochemical hot-potatoes, because they are prone to hydrolysis and decarboxylation. While these two high-energy reactions are exploited by nature for biosynthetic purpose, they plague the structural biologist. We developed molecules that look like malonyl-thioesters but are much more stable, thus we have chilled the hot-potato. These stable malonyl-thioester analogs have provided us with insight into the catalysis of three enzymes. Our preliminary studies with these malonyl-thioester analogs demonstrate that we will be able to generate insight into fatty acid and polyketide biosynthesis, paving the way for new routes to drugs, agrochemicals and biofuels.

The Yoshimoto research laboratory at UTSA harnesses the power of synthetic chemistry to solve challenging problems relevant to human health.

Artemisinin, one of the topics of the 2015 Nobel Prizes in Medicine, is an endoperoxide-containing sesquiterpenoid plant natural product used to treat malaria. The biosynthesis of the endoperoxide functional group, which gives the natural product its antimalarial activities, has been controversial. Using isotope-labeling strategies, we have elucidated the mechanism of the nonenzymatic endoperoxide forming cascade reaction that converts the precursor, dihydroartemisinic acid, to artemisinin in four steps: (i) first oxygen incorporation, (ii) C-C bond cleavage, (iii) second oxygen incorporation, (iv) and polycyclization to form artemisinin (1,2). Analogs of DHAA have been synthesized to probe endoperoxide formation, which led to the elucidation of the mechanism of the formation of the aromatic ring in serrulatene, an antibiotic plant natural product (3).

Secondly, human cytochrome P450 8B1, the oxysterol-12a-hydroxylase enzyme implicated in bile acid biosynthesis, is a therapeutic target to treat obesity. Preliminary studies involving the synthesis of a rationally designed inhibitor of P450 8B1 through the incorporation of a C12-pyridine in the steroid backbone, will be discussed (4).

1.         Varela, K., Arman, H. D., and Yoshimoto, F. K. (2020) Synthesis of [3,3-²H₂]-Dihydroartemisinic Acid to Measure the Rate of Nonenzymatic Conversion of Dihydroartemisinic Acid to Artemisinin. J. Nat. Prod. 83, 66-78

2.         Varela, K., Arman, H. D., and Yoshimoto, F. K. (2021) Synthesis of [15,15,15-²H₃]-Dihydroartemisinic Acid and Isotope Studies Support a Mixed Mechanism in the Endoperoxide Formation to Artemisinin J. Nat. Prod. 84, 1967-1984

3.         Varela, K., Al Mahmud, H., Arman, H. D., Martinez, L. R., Wakeman, C. A., and Yoshimoto, F. K. (2022) Autoxidation of a C2-Olefinated Dihydroartemisinic Acid Analogue to Form an Aromatic Ring: Application to Serrulatene Biosynthesis. J. Nat. Prod. 85, 951-962

4.         Chung, E., Offei, S. D., Jia, U. A., Estevez, J., Perez, Y., Arman, H. D., and Yoshimoto, F. K. (2022) A synthesis of a rationally designed inhibitor of cytochrome P450 8B1, a therapeutic target to treat obesity. Steroids 178, 108952

Abstract:

The human genome is composed of 46 DNA molecules — the chromosomes — with a combined length of about two meters. Chromosomes are stored in the cell nucleus in a very organized fashion that is specific to the cell type and phase of life; this three-dimensional architecture is a key element of transcriptional regulation and its disruption often leads to disease.  What is the physical mechanism leading to genome architecture? If the DNA contained in every human cell is identical, where is the blueprint of such architecture stored? 

In this talk, I will demonstrate how the architecture of interphase chromosomes is encoded in the one-dimensional sequence of epigenetic markings much as three-dimensional protein structures are determined by their one-dimensional sequence of amino acids. In contrast to the situation for proteins, however, the sequence code provided by the epigenetic marks that decorate the chromatin fiber is not fixed but is dynamically rewritten during cell differentiation, modulating both the three-dimensional structure and gene expression in different cell types.

This idea led to the development of a physical theory for the folding of genomes, which enables predicting the spatial conformation of chromosomes with unprecedented accuracy and specificity. Finally, I will demonstrate how the different energy terms present in our model impact the topology of chromosomes across evolution. Our results open the way for studying functional aspects of genome architecture along the three of life.

Bio:

Michele Di Pierro is Assistant Professor of Physics at Northeastern University and senior investigator of the Center for Theoretical Biological Physics — an NSF Frontier of Physics Center. He studied Condensed Matter Physics at the University of Rome “La Sapienza” and received a PhD in Applied Mathematics from The University of Texas at Austin. Prior to joining Northeastern University, he was the Robert A. Welch Postdoctoral Fellow at Rice University.

His research focuses on the physical processes involved in the translation of genetic information, a branch of biophysics which he refers to as Physical Genetics. His group develops novel theoretical approaches to characterize the structure and function of the genome using the tools of statistical physics, information theory, and computational modeling.

Graduate Student Profile

Abstract: 1,2-diamine substructures are prevalent functional motifs found in natural products, pharmaceutical compounds, and ligands. The interesting utilities of 1,2-diamines have inspired many synthetic chemists to design various methodologies for the preparation of these structures from simple precursors such as alkenes. Despite the well-established analogous dihydroxylation or aminohydroxylation of alkenes, the introduction of two amino groups across the double bond has been more challenging to accomplish. In this work, we described two different, but related methods using simple and easily accessible reagents for 1,2-diamination of alkenes. In the first method, an alkene undergoes 1,3-dipolar cycloaddition with an organic azide to form a 1,2,3-triazoline. Subsequent N-alkylation of the generated 1,2,3-triazoline gives the 1,2,3-triazolinium ion, which was then hydrogenated over Raney Ni with a balloon of H2 to produce 1,2-dimine. Traditionally, it has been believed that a 1,2,3-triazoline is an unstable species in the presence of heat or light and will readily extrude N2 to form an imine or an aziridine.  However, most of the 1,2,3-triazolines prepared in this work were stable to the extrusion of N2 at the temperature required for their formation. In the second method, the alkene undergoes 1,3-dipolar cycloaddition with a 1,3-diaza-2-azoniaallene (azidium ion) to afford a 1,2,3-triazolinium ion directly. The 1,2,3-triazolinium ions are reduced to the corresponding 1,2-diamines using the same conditions described above. X-ray crystallographic analysis and 1D/2D NMR spectra confirmed the stereochemistry of the synthesized 1,2,3-triazolinium ions and 1,2-diamines.

Biosketch: Christopher H. Hendon is an Assistant Professor of Computational ����vlog�ٷ���� at the University of Oregon, with interests in energy materials and coffee extraction. He obtained his BSc. Adv. HONS from Monash University (2011) and PhD from the University of Bath (2015). After a two year postdoc at Massachusetts Institute of Technology he joined the University of where his research group focuses the chemistry of transition metal clusters.

Prof. Hendon’s interest in coffee began during his PhD, and since  then has published several peer-reviewed articles and a book, Water For Coffee. He enjoys washed African coffees, dry rieslings, and east coast oysters.

Abstract: Although generally thought of as highly ordered crystals, all metal-organic frameworks contain defects. Some defects may reveal catalytic active sites or hint at competing material phases, while othersmay result in electronic doping. Modern computational approaches are well-suited to studying theemergent chemistry of these imperfections, and can be used to directly inform experiment and characterization of materials with properties that diverge from those gleaned from crystallography. This talk discusses the chemistry afforded by defects in metal-organic frameworks, with a focus on structural dynamics and adatoms, both promoted by Lewis basic sites within the scaffolds. The utility of these defects will be presented from the perspective of heterogeneous catalyst development.

This lecture series commemorates the life and legacy of Professor Susan Odom, an energetic, productive, and driven faculty member in the Department of ����vlog�ٷ���� from 2011 to 2021. It features speakers noted for outstanding research in Professor Odom’s fields of synthetic and materials chemistry.

Visit this page for more information on the Susan A. Odom lecture series.

Jianguo Mei is currently Richard and Judith Wein Professor of ����vlog�ٷ���� at Purdue University. His research interest centers on the design and development of semiconducting polymers for flexible electronics and bioelectronics. He has published over 100 peer-reviewed papers with over 14000 citations, 4 book chapters, and 18 granted US patents. Dr. Mei is a recipient of an NSF CAREER award, the Office of Naval Research Young Investigator Award (ONR YIP), the ACS PMSE Young Investigator, the ACS Division of Organic ����vlog�ٷ���� (DOC) Academic Young Investigator, and Purdue’s Teaching for Tomorrow Fellowship. He is also a co-founder of Ambilight Inc, a venture-backed startup (Series C) dedicated to the commercialization of roll-to-roll manufactured thin-film electrochromic for smart windows.

Abstract: The concept of organic electronics emerged in the late 1980s. The promise of solution-processing, mechanical flexibility, light weight and low cost has been driving the development of organic semiconductors and electronics. Three decades of continuous efforts from the community have nurtured the technological maturity of a number of organic electronics. Part of my research group has been actively pursuing the development of polymer-based electrochromic technology. In this talk, I will share our journey of moving electrochromic technology from lab to fab. In particular, I will introduce our latest development of highly conductive transparent organic conductors (TOCs) and ultra-high contrast transparent-to-colored electrochromic polymers.

Prof. Sachin Handa is currently a tenured associate professor in the chemistry department at the University of Louisville. In less than four years, he completed his Ph.D. in 2013 and then worked as a postdoc fellow with Prof. Bruce Lipshutz from 2013-2016. He started his independent career in 2016. His research interests are green chemistry, energy, nanocatalysis, and photochemistry. Recently, he has received the NSF CAREER award, Ralph E. Powe Junior Faculty Enhancement Award in Physical Sciences by Oak Ridge Associated Universities, and Peter J. Dunn Award for Green ����vlog�ٷ���� and Engineering Impact in the Pharmaceutical Industry. Besides fundamental research, his research significantly focuses on synthetic problems associated with the pharmaceutical industry. Currently, his research is funded by NSF, Novartis Institutes for BioMedical Research, Novartis Pharmaceuticals Switzerland, AbbVie, Takeda, and Biohaven Pharmaceuticals. He also serves on editorial boards of various journals, such as ACS Sustainable ����vlog�ٷ���� and Engineering, Green ����vlog�ٷ���� Letters & Reviews, and Molecules.

Abstract

Water appears to be the only solvent for life to occur on this planet; nonaqueous solvents may support life elsewhere in the universe.

Faculty Host: Dr. Robert Grossman

Abstract: Oxidative Phosphorylation occurs within the inner mitochondrial membrane producing ATP for the cell’s energy needs. The Electron Transport Chain carries out the transfer of electrons from electron carriers through a series of proteins to form a proton gradient across the membrane. This gradient acts as the energy source needed to put a phosphate onto ADP. With the large amounts of free electrons and oxygen within the mitochondria, an inevitable by-product of free radicals in the form of superoxide are produced. Superoxide (O-?2) is an extremely reactive radical that can go on to perform further reactions leading to the formation of more radicals. When these radicals and reactive oxygen species are kept in balance they act as signaling molecules for the cell. A network of antioxidant proteins helps the cell to keep this balance. However, when there is an overload of radicals and ROS within the cell leading to oxidative damage and becoming detrimental to the cell’s ability to survive.  The brain is made up of different types of cells, neurons, and glia, that are rich in polyunsaturated fatty acids and have an abundance of O2. The combination of these things is what allows the brain to work with such high function, but it is also this combination that can lead to unfavorable reactions. The abundance of O2 allows for higher changes of free radicals and reactive oxygen species which can interact with the polyunsaturated fatty acids in a process called lipid peroxidation. Lipid peroxidation results in the formation of 4-hydroxynonenal (HNE) which has deleterious effects within the cell.  HNE adducts to proteins on a cysteine, lysine, or histidine. When these amino acids are located towards the inside of the protein it causes a conformational change of the protein and therefore a loss in function.  The adduction of HNE to proteins has been observed in different brain related diseases such as Glioblastoma and Alzheimer Disease.  Glioblastoma is one of the most difficult forms of cancer to treat due to location of the tumor and its resistance to radiation. Oxidative damage within the tumor cells does not seem to cause the same deadly effects as it would to the surrounding cells. When tumor cells have a large amount of oxidative damage there is a need to rid the cell of the affected proteins. This is in the form of extracellular vesicles (EVs). The findings of this dissertation elucidate the mechanism by which these EVs aid in the progression of the tumor cells. EVs bleb from the surface of the cell carrying the HNE adducted proteins into the extracellular space and encounter the surrounding glial cells and neurons. When the EVs are taken up by the glial cells, such as astrocytes, this induces the production of ROS in the form of hydrogen peroxide. This ROS is key in inducing proliferation of the tumor cells and furthering radiation resistance.  Alzheimer Disease has also been shown to have HNE adducted proteins and oxidative damage. One such pathway is affected in Alzheimer disease, the Pentose Phosphate Pathway, depending on the apolipoprotein E (ApoE) allele status of the cell. There are three variations of this gene, E2, E3, or E4, with the most common being E3. Those who have ApoE4 have a higher risk of developing Alzheimer Disease. ApoE4 allele is also seen in conjunction with higher oxidative damage and HNE production within the cell. The findings in this dissertation show the correlation between the ApoE allele status and the oxidative damage.