According to Rita Charon, founder of the developing field of narrative medicine, "medicine practiced with narrative competence, called narrative medicine, is proposed as a model for humane and effective medical practice," which "offers fresh opportunities for respectful, empathetic, and nourishing medical care" (Charon, 2001). Narrative medicine is composed of three key practices: close reading, reflective writing, and active listening. Developing each of these skills, Sharon proposes, can foster compassion and empathy in medical providers. The demonstration of these practices has been shown to "facilitate an authentic partnership by building empathy and trust," as well as "promote physician well-being and prevent burnout" (Khawand-Azoulai, et. al. 2022, Stumbar, S. E et. al. 2020). Medical education currently is striving to incorporate humanistic training to develop a holistic approach to patient care, but narrative medicine training has yet to be extensively explored in undergraduate pre-health education (Pentiado, J. A. et. al., 2016, Barron, L., 2017). Narrative competence, defined by Charon as "the ability to acknowledge, absorb, interpret, and act on the stories and plights of others," has been proposed as a pre-requisite to developing good patient-care skills (Charon, 2001, Baron, L., 2017). The incorporation of humanistic training for undergraduate pre-medical students in the form of narrative medicine practices can prepare future professional school students to begin developing a patient-centered perspective of healthcare. The undergraduate years have the "potential to shape the kinds of caregivers we want for our patients, for friends, for our families, and for ourselves" (Barron, L. 2017). It is therefore important to gain an understanding of how medical humanities education can impact undergraduate students because foundational knowledge of these concepts prepares students for later development of humane medical practice in professional school. The three avenues of narrative medicine training that I have chosen to analyze include a narrative medicine workshop series, a group of pre-health students called the Illness Narrative Listening Project that gathers regularly to intentionally listen to patients stories, and lastly, my own reflective writing from experiences in medical contexts. Data is collected through a mixed methods approach, gleaning insight through both qualitative and quantitative research methods, in the form of interviews and surveys respectively, will illuminate the complexities of the research question. The goal of the workshops and listening project is to teach these practices to undergraduate students in order to explore if the same benefits seen in clinical practice and medical education could be demonstrated in undergraduate pre-health education.

Alzheimer’s disease (AD) currently afflicts well over six million people in the United States, and this number is projected to increase exponentially in the coming years. While much remains to be understood about the causes and pathogenesis of AD, two potential risk factors are chronic insufficient sleep and long-term consumption of an unhealthy diet. Both of these lifestyle factors are often studied separately, and evidence suggests that each has negative impacts on brain health and cognitive function, perhaps due to increases in inflammation, which itself is associated with increased anxiety and cognitive dysfunction. The current study investigated the combined effects of long-term consumption of a typical American-style diet (TAD) and six weeks of chronic sleep restriction on locomotor activity and anxiety-like behavior in male and female wild-type mice not otherwise predisposed to disease pathology. Female mice that underwent sleep restriction and consumed the TAD displayed greater anxiety-like behavior compared to mice that the TAD and did not undergo sleep restriction. This difference was not observed in male mice. Furthermore, male mice that underwent chronic sleep restriction displayed greater locomotor activity compared to controls. These differences were not observed in females. Given the prevalence of AD and the projected rise in AD cases, understanding how controllable lifestyle or environmental factors can increase AD risk is essential. Importantly, as AD is more prevalent in women compared to men, it is imperative that research efforts utilize male and female animals seek to understand the mechanisms driving this phenomenon.

There is an oxidative stress component to a wide range of neurobiological diseases. In Alzheimer’s disease (AD), secondary brain injury is associated with an imbalance between oxidant and antioxidant agents. This imbalance contributes to the pathophysiology of AD through the oxidation of macromolecules, destabilization of neuronal cells, and generation of ROS that upregulates synthesis and deposition of p-tau and Amyloid-β (Aβ). The expression of antioxidant defense enzymes can decrease damaging reactive oxygen species, so some efforts to alleviate secondary injury focus on this mechanism of reducing oxidative stress. One pathway that is activated in response to oxidative stress is the Nrf-2/ ARE pathway. Under stress conditions, the protein sensor for oxidation levels Keap1 that is bound to Nrf2 is oxidized, and Nrf2 levels are stabilized and subsequently increased in the cell. The Nrf2 transcription factor then translocates into the nucleus and binds to the antioxidant response element (ARE) promoter to turn on the expression of downstream antioxidant genes. The genes that are expressed include heme-oxygenase (HO-1) and NADPH quinine oxidoreductase 1 (NQO1). These antioxidants can then regulate the redox balance in the internal environment and reduce oxidative stress. The goal of my research is to design an assay to measure Nrf2 activation, so we can test drugs shown to reduce oxidative stress in vitro.

Alzheimer’s disease (AD), currently the seventh leading cause of death in the United States, is a neurodegenerative disease characterized by amyloid beta (Aβ) plaques and chronic inflammation in the brain. Microglial cells, which act as the immune cells of the central nervous system (CNS), function in response to Aβ by secreting pro-inflammatory cytokines and reactive oxygen species (ROS). Microglial activation is a healthy response in the brain, but chronic activation of these cells and thus chronic secretion of neurotoxic factors creates a cyclic process that leads to neuronal cell death. In order to protect against oxidative stress, cells activate the nuclear factor erythroid 2-related factor (Nrf2) pathway. Nrf2 is a transcription factor that regulates the expression of antioxidant enzymes, which can protect the cell from ROS. Here we focus on the therapeutic potential of cannabidiol (CBD) to mitigate oxidative stress in both microglial and peripheral macrophage cell lines. We show that CBD can activate the Nrf2 pathway and thus increases the expression of several antioxidant proteins such as Heme oxygenase-1 (HO-1). This research is significant because it could provide evidence for the use of CBD as a potential therapy in AD patients.

Zebra mussels are an introduced species that has spread throughout much of the eastern United States and recently invaded Texas. These freshwater mussels cause ecological damage by reducing food available and outcompeting native clams. They cause significant economic damage by attaching to hard surfaces in the water such as pipes to factories and water treatment plants. Understanding where they might spread is an important step in controlling their invasion. Predicting their distribution can be challenging; however, several factors are indicative of where zebra mussels may spread (pH levels, temperature, calcium). Of these factors, calcium is currently viewed as the most significant. Zebra mussels needing calcium for general blood physiology, creating their calcium carbonate shells, and by developing larvae which have small shells. The working model is that zebra mussels will thrive in waters with calcium levels greater than 27mg/L, zebra mussel adults may survive but the larvae may not survive in calcium levels between 27-12 mg/L, and less than 12mg/L of calcium is too low for any stage of mussels to survive for an extended period. My projected look at survival of zebra mussels at varying concentrations of calcium in waters on zebra mussels. Differing calcium levels of 0, 5, 10, 20, and 30 mg/L in artificial pondwater were be used to determine at what levels of calcium zebra mussels are able to survive.

Cryptococcus neorformans is a fungal pathogen that mainly affects immunocompromised patients and is opportunistic as it invades the central nervous system. In the Wormley research lab, we are currently working with multiple genes that have been shown to be involved in lipid metabolism. C. neorformans. Using the TRACE procedure; Transient CRISPR-Cas9 coupled with Electroporation is hypothesized to be a reliable method in order to knock out genes in C. neoformans. This specific project we have been working on will lead to a knockout by using CRISPR methodology to create a Cryptococcus neoforman deletion construct for an associated gene. We are analyzing identified genes that have been found to be upregulated in C. neoformans, multiple of which have been shown to be involved in lipid metabolism and virulence. By characterizing the role of these genes and certain proteins this project aims to deepen the knowledge of the roles of lipids in pathogenesis and hopefully develop ways to combat infection of people with weakened immune systems. To further characterize the role of these genes in virulence we focus on the gene CNAG_00474, which was upregulated in C. neoformans in the presence of arachidonic acid. To achieve this we will generate a KO using the TRACE technique. The overall problem in this study is the implications these fungal proteins may have and the lack of understanding surrounding their involvement which is essential to research in order to create a pathway leading toward potential drug targets. The methodology of this project includes the amplifying promoter and end sequences from the unidentified protein to fuse the primer with sgRNA to create a construct ultimately. From here, amplifying the ‘arms’ of the target protein and the selection marker from a plasmid (in this case NAT) will use PCR to fuse the marker and arms together and create the deletion construct. Once we confirm the gene has been knocked out we will analyze its role in virulence by assessing phenotypic characteristics in vitro and in vivo. I am hoping in the near future to have the specific KO ready to be able to confirm it via PCR.

Marine environments are at risk of contamination from oil refinery effluents, major oil spills, and wastewater runoff. To identify and mitigate such risks, the EPA requires toxicity testing of marine effluents. The larval growth and survival (LGS) test, featuring either sheepshead minnows (SHMs) or inland silversides (INS), is currently used to screen marine effluents for acute toxicity; however, the use of fish larvae represents an animal welfare concern, especially in light of legislation calling for adherence to the 3Rs of animal research. The fish embryo toxicity (FET) test and mysid growth and survival (MGS) test may represent viable alternatives to LGS tests as the FET test uses fish embryos (which are thought to experience less pain than older fish), while the MGS test uses invertebrates. The objective of this study was to determine if the FET and/or the MGS tests produce similar results as the LGS. To accomplish this, INS LGS, SHM LGS, INS FET, SHM FET, and MGS tests were run using phenanthrene, an environmentally-relevant component of crude oil. Results revealed that the LC50 values obtained from the MGS and INS LGS tests were comparable and that both were significantly lower than that of the other test types, suggesting that the MGS test may be a viable replacement for the LGS tests. This was further substantiated when growth metrics were evaluated. In contrast, the LC50 values obtained from both FET tests were significantly higher than those of the other test types indicating a relative lack of sensitivity. However, when hatchability was included as a test metric, the sensitivity of the INS and SHM FET was enhanced indicating that the inclusion of hatch may improve FET test performance.

Due to our rapidly aging population, 6.5 million Americans currently have Alzheimer’s disease (AD), and this is predicted to increase to almost 14 million in the next 40 years. AD is more prevalent in western societies, and researchers suggest that this may be due to the typical Western diet. In contrast, AD prevalence is lower in Mediterranean regions, where a healthier diet could be a contributing factor. Therefore, this research examined the neuroprotective potential of a Mediterranean diet against AD pathologies and inflammation in mice. Our lab designed two experimental rodent diets, one that mimicked a typical Western-style diet, and another that mimicked a typical Mediterranean diet. We examined the lifelong effects of diet on biological markers of AD, including amyloid beta, a protein that aggregates together to form plaques in the AD brain, and pro-inflammatory cytokines, which are associated with increased inflammation. We hypothesized that the Mediterranean diet has the potential to mitigate these AD pathologies and therefore, could potentially be used as a future preventative strategy for AD.

Bacillus anthracis is the causative agent of anthrax. Previously, our lab identified the clpX gene as critical for virulence in B. anthracis. The ΔclpX mutant exhibited decreased cell wall integrity and increased susceptibility to cell-envelope active antibiotics. ClpX is one component of the intracellular caseinolytic protease ClpXP that degrades multiple proteins including transcriptional regulators. To understand changes in gene expression in ΔclpX, a microarray comparing WT and ΔclpX was conducted. This project focuses on msrA, an upregulated gene in ΔclpX. MsrA is an antioxidant enzyme that reduces methionine-S-sulfoxide to methionine but also impacts cell wall strength in S. aureus. This study will determine if loss of the msrA gene impacts antibiotic susceptibility. We hypothesized that since ΔmsrA is upregulated in ΔclpX, ΔmsrA would exhibit the opposite phenotype. Surprisingly, we find that ΔmsrA has significant growth inhibition in the presence of penicillin. However, we do not find susceptibility with other antibiotics, such as daptomycin, nor does it appear to be more susceptible to other clpX-related stress responses such as heat or acid stress. Future research will test ΔmsrA susceptibility to additional antimicrobials, such as the antimicrobial peptide LL-37 and the antibiotic vancomycin, as well as ΔmsrA virulence in vivo with the Galleria mellonella infection model. We will also complement ΔmsrA to confirm the phenotypes are due to loss of the msrA gene. This research is important as it aids our understanding of bacterial defenses and may provide new drug targets to help combat rising antibiotic resistance.

The Molding Melanin Magic mentorship program through TCU Pre-Health is geared to impact minority female student populations at the Texas Academy of Biomedical Sciences (TABS) in Fort Worth. The program provides small group mentorship as high school students are paired with a college student in their area of interest. Along with mentorship, workshops are utilized as a method of increasing confidence, exposure, and overall knowledge about college and STEM careers. By coupling workshops and mentorship, the Molding Melanin Magic program seeks to encourage mentees to serve as mentors along their educational journey, and apply for college and professional school to pursue a career in STEM.

Spiders are sentinel species, organisms that serve to map the bioavailable fraction of contaminants in an ecosystem by retaining their contaminants in their tissues. For example, spiders in the families Tetragnathidae and Araneidae are frequently used as sentinels of mercury contamination of aquatic ecosystems. Spiders are frequently preserved in alcohol prior to contaminant analysis but the impact of contamination on mercury concentrations in spiders has not been assessed. The objective of the present study was to determine the effects of different preservation methods on mercury concentrations in tissues of spiders in the families Tetragnathidae and Araneidae. The spiders were collected along water sources using nets and gloved hands. The Tetragnathids were collected from grassy terrain or a bridge overhanging the water of Lake Weatherford. The araneids were collected from a boat dock overhanging Eagle Mountain Lake. On site, each spider was placed into its respective bottle of varying ethanol or Ziplock's for freezing. Individual spiders were placed into one of three different concentrations of ethanol (100%, 95% , 70%) or frozen. Following about two months of preservation, the spiders were dried and run through the DMA-80 collecting the data for data analysis. Data xxxx *insert conclusion info*

Role of ClpX in the stress response and virulence of Bacillus anthracis: protease or chaperone?
Lillian Wilson, Vuong Do, S.M McGillivray
Department of Biology, Texas Christian University

Anthrax is a lethal infectious disease caused by the bacterial pathogen Bacillus anthracis. Our lab studies the virulence and antibiotic resistance of B. anthracis and we have identified a chromosomal gene clpX, as an important virulence factor, as its loss increases susceptibility to cell-envelope targeting antibiotics such as penicillin, daptomycin, and the antimicrobial peptide LL-37. ClpX is an ATPase that can act autonomously as a chaperone, or with a proteolytic core, ClpP, to degrade proteins. To investigate the mechanism ClpX uses, a plasmid pclpXI264E was designed with a mutation in clpX (I264E) that prevents ClpP binding and inhibits the formation of the ClpXP protease but does not disrupt the chaperone activity of ClpX. We used this to create 4 strains in the unencapsulated Sterne strain: wild-type and ∆clpX containing the empty inducible plasmid pUTE657, complementation plasmid with the non-mutated clpX gene (∆clpX + pclpX), and the mutated plasmid (∆clpX + pclpXI264E). Prior research done on these strains confirmed that ClpX relies on protease activity in antimicrobial stress; however, our goal was to assess its response in other environmental stressors such as acid stress, heat stress, and its virulence in vivo with the Galleria mellonella infection model. We find that that the protease activity of ClpX is important for all of these stresses. These results build on our earlier understanding and demonstrate that formation of the ClpXP protease is critical and any future development of drugs targeting the ClpX system should focus on protease formation rather than chaperone activity.

This research is focused on gaining a better understanding of PKC-epsilon a calcium-dependent protein kinase involved in a wide range of cellular functions including cell proliferation, survival, and apoptosis. The interest in PKC-epsilon derives from the discovery of a de novo mutation in the PKC-epsilon gene in patients suffering from SHORT syndrome. This syndrome is a debilitating disorder characterized by short stature, hyperextensibility, ocular depression, Rieger anomaly, and teething decay. The project involved recapitulating the naturally occurring de novo mutation in vitro as well as determining if other mutations in PKC-epsilon could cause similar disease-state phenotypes. Using a technique known as Site Directed Mutagenesis mutations were introduced into the PKC-epsilon gene and the effects of these mutations on the protein expression were assessed. This mutational analysis will help identify the regions of PKC-epsilon that are vital for its function. This will help elucidate the effect of the same mutations in patients and could help predict the severity of disease. Obtaining a clearer picture of the different regions of the PKC-epsilon protein allows for future studies to focus on successfully fixing these regions when they become damaged and could therefore be used to help patients with SHORT syndrome.

N-terminal acetylation is essential for the stability, activity, and targeting of proteins in eukaryotes. However, most eukaryotic proteins are not acetylated when expressed in bacteria. Therefore, it is of practical significance to control N-terminal acetylation of recombinant proteins in bacteria. RimJ is an N-terminal acetyltransferase (NAT) known to acetylate many recombinant proteins with a narrow substrate specificity in E. coli. This project is aimed to increase the applicability of RimJ for the N-terminal acetylation of a broad range of recombinant proteins.
Based on the AlphaFold-predicted structure of E. coli RimJ, we predicted that six amino acids (Y35, E46, R49, Y106, Y170, and L171) may recognize substrate proteins in the active site. We created RimJ variants, in which one or two of these amino acids are changed to alanine, a small neutral amino acid, so that the active site becomes larger to accommodate substrate proteins containing bigger N-terminal amino acid residues. The RimJ variants were created using site directed mutagenesis, confirmed by DNA sequencing, and co-expressed with Z domain mutants that were not acetylated by the wildtype RimJ. The Z domain mutants were isolated by immobilized metal ion affinity chromatography and analyzed by mass spectrometry for their N-terminal acetylation patterns.

In the past two centuries, tuberculosis (TB) has killed over 2 billion people. TB is an airborne contagious infection that usually attacks the lungs and can spread to the brain and spine. Today TB is treated with 6-12 months of antibiotics and if the medication is ended early the treatment is ineffective. There are also drug resistant forms of TB that are caused by mutations of the bacteria and this process is sped up by the overprescribing of antibiotics which is a growing problem. Dr. Jeffrey Aube created a drug that attacked both non replicating and replicating TB bacteria in the body. This was a major step from previous medicines that could only attack one. We are creating a library of TB drugs that are customizable, efficiently made, and easily purified. These customizable drugs will not only create a large range of effective medicines but also can treat TB that is resistant to antibiotics. Tuberculosis is still one the leading infectious disease killer today, claiming 1.5 million lives annually and we are making drugs that could change that and save millions of lives.

Pyridinophane molecules have recently been shown to have both antioxidant and pharmacological properties suitable for therapeutic applications targeting neurodegenerative diseases, including Alzheimer’s. We have synthesized derivatives of the parent molecules with substitutions on the pyridine ring (L1) or on the ‘side’ of the macrocycle (L2) designed to increase the antioxidant activity beyond that of the parent molecule in hopes of producing a molecule suitable for pharmacological testing in animal models. The lab is currently working towards substituting on the ‘bottom’ of the macrocycle (L3) to characterize and compare substitutions at each of the three positions.

Macrocycles are molecules containing at least one ring composed of 12 or more atoms. Macrocyclic drugs have been used clinically for decades. Many interfere with protein-protein interactions. Therapeutic intervention requires that macrocycles remain flexible to facilitate the adoption of different conformations. Specifically, small compact hydrophobic conformations are required to cross cell membranes. The ability of a macrocycle to perform these contortions is predicted by its octonal:water partition coefficient, its so-called logP. Macrocycles (as well as small molecule drugs) that are suitable for oral delivery have a logP value <5. In this study, methionine containing macrocycles are studied. The studies commence with the synthesis of a macrocycle with a dimethylamine auxiliary group that allows for solution-phase NMR analysis. Upon formation of the macrocycle, oxidation to sulfone and sulfoxide derivatives was executed. These macrocycles are of interest because the impact that oxidation has on log P values has not been reported. Additionally, S-oxidation could change the conformation of the molecules. Synthesis beings with substitution of trichlorotriazine with BOC-hydrazine, followed by treatment with methionine in basic conditions. The final substitution of the triazine installs the auxiliary group, dimethylamine (NMR). Amidation with 1,1-diethoxypropyl amine using a peptide coupling reagent yields the monomer. Cyclization using TFA yields the macrocycle. NMR spectroscopy confirms macrocyclization and gives insight into the solution conformation of the molecule. Oxidation strategies and the results of logP analysis will be developed.

Proper functioning of BRCA1 and PALB2 are essential in preventing tumor formation. Upon detection of DNA damage, BRCA1 binds to PALB2, leading to formation of the BRCA1-PALB2-BRCA2 DNA repair complex which is recruited to double-stranded break sites. Mutations in the genes coding for BRCA1 and PALB2 may disrupt this binding interaction, causing obstructions in DNA damage repair and increased breast cancer risk. Variants of unknown significance (VUS) found in breast cancer patients are genetic variants whose impact on the health of individuals are not yet known. Our study characterizes the effects of these VUS on the BRCA1-PALB2 binding interaction. Site-directed mutagenesis was used to generate BRCA1 and PALB2 VUS. It was found that the binding event between BRCA1 and PALB2 is enthalpic in nature and can be measured adequately via isothermal titration calorimetry (ITC). Thus, ITC was employed to identify whether the VUS disrupted binding. ITC data suggest that several PALB2 and BRCA1 VUS exhibit disruptions of the BRCA1-PALB2 binding interaction, but to varying degrees. We will share the data for variants tested thus far and emerging themes for prediction of the roles residues in both proteins play in the vital interaction.

Alzheimer’s Disease (AD) affects over 6.5 million Americans over the age of 65. Previous research links AD with the aggregation of Amyloid-beta-40 (AB40) in the brain, which creates neurotoxic plaques, causing further development of AD in the brain. A potential therapeutic mechanism in the treatment of AD is using drugs that will prevent the formation of these plaques, which is possible with Metal Chelation Therapy.
Metal ion chelation ideally stops metal ions from aiding in the aggregation of AB40. However, to deliver metal chelating agents to the brain, a drug-delivery mechanism is required that will be able to deliver this medicine across the Blood-Brain Barrier. Porous silica is a potential drug delivery material due to its particle size, high loading capacity, tunability, and biocompatibility. Along with these characteristics, porous silica can create a “sustained” release of a given drug, allowing for a slow and steady release profile, reducing the risks of medication side effects.
This project seeks to establish the optimal loading capacities of a class of potential AD therapeutic molecules known as pyclens into porous silica, each with different pyridyl moieties and chemical functionalities along the rim of the molecule. Encapsulation efficiencies measurements for these pyclen derivatives reveal loading percentages in the 10-19% range, varying by pyclen identity. Additionally, release studies monitored diffusion over time to find which pyclen molecule achieved “sustained” release. All loaded pyclen species were able to show sustained release after 20 minutes. Additional release studies of these molecules in the presence of copper (Cu2+) remain to be completed to ascertain the ability of release drugs in the presence of Cu2+ to inhibit AB40 aggregation, followed by independent assays of AB40 solubility under such conditions.

Two proteins, BRCA1 and PALB2 are known to aid in DNA damage repair through homologous recombination. Both proteins are phosphorylated upon DNA damage, and we hypothesize that the phosphorylation of these proteins acts as an “on switch” to allow the proteins to interact and form the DNA repair complex. To test this hypothesis, we mimicked phosphorylation on the BRCA1 protein to test the binding affinity between BRCA1 and PALB2. Phosphomimicking mutants are created by mutating an amino acid with the ability to be phosphorylated and acquire a negative charge, such as threonine (T) or serine (S), to a negatively charged amino acid, such as glutamic acid or aspartic acid. Recent research has shown that specific phosphorylation sites, such as T1394 in BRCA1 are essential to DNA damage and repair in cells. We have created a phosphomimic mutant in this specific T1394 site by mutating threonine to glutamic acid. We are currently measuring the effect that this mutation has on the ability of BRCA1 to bind to PALB2 in vitro. The obtained data will reveal whether phosphorylation has an impact on the interaction between these two proteins or not.

To fight disease, pharmaceutical companies have historically prepared small molecules designed to interfere with specific sites on proteins (enzymes) to prevent chemical reactions from taking place. However, a second paradigm for interfering with proteins has gone largely unexplored--blocking protein-protein interactions. To accomplish the latter, large molecules are needed to bind to large areas on the protein target. However, large molecules present additional challenges. Typically, they are hard to synthesize, not orally available, and typically cannot cross cell membranes. Nature has designed large molecules like cyclosporin that should not work as drugs based on our current understanding. Despite its size, cyclosporin is orally available and can cross cell membranes. This research explores the design, synthesis, and conformational analysis of similar large ring-shaped molecules, so-called macrocycles. In this work, we are increasing the size of the ring-shaped molecule. By increasing the size of the ring-shaped molecule and varying the amino acid (in this case, valine), we are expanding the possible ways in which our macrocycle may interfere with protein-protein interactions. Here, a 26-atom macrocycle is reported. 1H NMR spectroscopy reveals a protonated molecule that is highly dynamic which has access to a beta-sheet conformation.

Macrocyclic drugs adopt multiple conformations--a behavior referred to as chameleonicity--to navigate hydrophobic cellular membranes and aqueous intracellular environments. The rules for understanding this behavior are beginning to emerge through studying existing drugs and the synthesis of model systems. Historically, one challenge to macrocycle synthesis is low yield reactions. To this end, dynamic covalent chemistry has been explored. Here, macrocycles are afforded readily by dimerization with the formation of two hydrazones.

The efficiency of the macrocyclization reaction led to the hypothesis that upon formation of the first hydrazone, the acyclic intermediate was preorganized to place the hydrazine and acetal in close proximity thereby reducing the likelihood of oligomeric or polymeric products. The preorganization could result from a network of hydrogen bonds. Moreover, in an acidic environment, wherein the triazine ring is protonated, the opportunity for bifurcated hydrogen bonds emerge. Computation has been used to identify sites for protonation and the energetic contributions of hydrogen bonding.

To explore templating and the role of protonation in the formation of hydrogen bonds, model systems were prepared that emulate ‘half’ of the macrocycle. The acetylated aminoacetal offers a well-resolved NMR spectrum. In contrast, hindered rotation about the triazine-N bond leads to a mixture of rotamers in the hydrazine component. However, upon condensation, a single rotamer is observed and resonances corresponding to the hydrogen bonded protons emerge downfield between 7-12 ppm. Computation provides estimates of the energetic contribution of the bifurcated hydrogen bond as well as the hydrogen bond formed in the absence of protonation. The results of titration and variable temperature NMR experiments will also be described.

The mis-regulation of reactive oxygen species and transition metal ions contributes to the onset of Alzheimer’s Disease. Reactive oxygen species are a natural byproduct of metal redox cycling that occurs within the body and are important in processes like homeostasis and various pathways of cell signaling. Two series of pyridinophane ligands were produced and evaluated for the ability to target the molecular features of Alzheimer’s Disease. The functionalized pyridinophanes were chosen to analyze their blood-brain barrier permeability and radical scavenging ability when included within a molecular scaffold. Preliminary results with the DPPH assay indicated a significant increase in radical scavenging activity for ligands containing electron-donating substitutions in comparison to the parent ligands. These results warrant further exploration into the mechanism of the activity observed.

Petroleum crude oil, unconventional crudes, and renewable bio-crudes are essential materials in our everyday lives. They fuel vehicles, heat buildings, provide electricity, and are used to produce a multitude of other materials, such as plastics and solvents. Crudes are highly complex chemical mixtures, estimated to contain between 100,000 and 100,000,000,000,000,000 unique molecules. Since 2015, single-molecule imaging has visualized hundreds of chemical structures, and historical literature has published thousands of proposed structures. This project builds an open database populated with published crude structures enabling data-driven analysis of these structures, and detailed workflows, allowing for easy future insertion of new molecules into the database. This database can be used to make calculations and predict characteristics of molecules, such as viscosity, density, and reactivity, which are all critical in refinery plants, transportation, and usage of these fuels. Performing queries on the molecules in the database to filter for specific characteristics allows scientists to develop more successful experiments by refining their hypotheses to account for the query results displaying possibilities of their desired outcome.  

This research aims to understand how to design and control molecular hinges. The molecular hinges of interest are nano-sized equivalents of door hinges. Such hinges could find applications in new materials or the design of new drugs.

The foundation for this research was the observation that a large, ring-shaped molecule - a so-called macrocycle – prepared by a colleague folded and unfolded rapidly at room temperature. Two research questions arose from this observation: was the hinge behavior unique to this molecule, and could the hinging rate be controlled?

Addressing these questions required the three-step synthesis of a related macrocycle. This new molecule had groups equivalent to putting grit around the hinge's pin. The difference in the rate of hinging motion due to the addition of these groups was observed using a technique called variable temperature NMR spectroscopy.

The results of this work revealed that hinging is a general phenomenon for some of these macrocycles. Second, the 'molecular dirt' designed into this new hinge reduced the rate of hinge motion from 2000 times per second to 20 times per second.

This work is being written up for communication to the Journal of the American Chemical Society based on the novelty of this molecular device and the scientific community's interest in molecular machines.