Quantifying biodiversity in an urban area forest is essential to informing conservation in an era of climate change. This research project aims to characterize biodiversity in Spalding Conservancy through the use of camera trapping, small mammal image capture, and passive acoustic monitoring for birds and bats to survey which species are present. Preliminary results suggest that there is a population of big brown bats, silver-haired bats and hoary bats that utilize a diverse set of habitats: meadowland, edge habitats, interior forests, and marshland. These results suggest that the ecosystem can support different species of bats at a time indicating that niches can overlap and support an abundance of bats. Results from ongoing sampling will be presented including spatial and temporal distribution of birds, large mammals, and small mammals. Results from my research are intended to inform management of Spalding Conservancy to improve habitat quality management and in turn increase biodiversity. This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Daniel Ardia, Department of Biology

Side effects from hormonal contraceptives, namely mood changes, are one of the primary reasons these medications are discontinued. The impact of hormonal contraceptives on mood/behavior has been extensively studied, yet inconsistent results in current literature creates a barrier between symptomatic women and treatment development. Previous studies found that oral contraceptive use is associated with decreased endogenous testosterone levels. Despite an established connection between testosterone deficiency and mood changes, the relationship to hormonal contraceptive-induced mood changes has not been critically examined. This study used a rat model to assess anxiety behaviors following hormonal contraceptive administration and analyzed testosterone levels to determine the relationship between these factors. Each rat experienced 4 treatment phases with varying levels of synthetic estrogen and progesterone, and testosterone levels were analyzed using fecal samples. The goal of this experiment was to determine how/if testosterone contributes to mood changes associated with hormonal contraceptive use in humans. This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Ryan Lacy, Department of Psychology

The unnatural amino acid 4-Cyano-L-Phenylalanine (pCNF), is an effective vibrational reporter used to probe local protein regions. pCNF contains a nitrile group which falls in a relatively quiet portion of the IR spectrum, with different stretching frequencies in polar and nonpolar environments. We hypothesize that pCNF could also be used to understand local folding/unfolding patterns in proteins as the local solvation environment of many sites change during protein unfolding. This summer, pCNF was incorporated into Adenylate Kinase at various sites using the Amber codon suppression methodology. By incorporating pCNF at a wide range of sites in the protein, we have collected temperature-dependent IR data suggesting that the protein does not globally unfold at the same temperature and the folding pattern is not reversible. Additionally, it has been determined that further purification of Adenylate Kinase on fast protein liquid chromatography (FPLC) is necessary to obtain homogeneous protein samples for IR studies.  This project was supported by funding the F&M’s Committee on Grants Program, Eyler Fund and the National Science Foundation.

Project Mentor:  Professor Christine Piro, Department of Chemistry

Cu₂₋ₓS/Cu₂₋ₓSe nanoparticles are precursors for a variety of metal sulfide/selenide particles and post-synthetic anion exchange offer pathways to create various such heterostructures. Long-chain dialkyl diselenides have been previously implicated as key drivers in Se-anion exchange. In this study, we investigate the post-synthetic transformations of roxbyite copper sulfide nanoparticles induced by diorganyl diselenides, including diphenyl diselenide, didecyl diselenide, and dibenzyl diselenide. Our results indicate that didecyl diselenide facilitates anion exchange, yielding metastable wurtzite Cu₂₋ₓ(S, Se) nanoparticles. In contrast, both diphenyl and dibenzyl diselenides dissolve roxbyite and produce the unstable berzelianite copper selenide phase. Characterization was conducted using XRD, TEM, SEM-EDS, and remote STEM-EDS. Bond strengths for the diselenides were calculated using a ReaxFF force field and DFT calculations, with molecular dynamics simulations supporting the rationalization of distinct transformation pathways. Anion exchange driven by dialkyl diselenides is proposed to occur due to the comparable C-Se and Se-Se bond strengths, promoting the formation of H₂Se. This study provides insights into the mechanisms of anion exchange and offers guidance for the design of molecular drivers for such transformations.  This project was supported by funding the F&M’s Committee on Grants Program.

Project Mentor:  Professor Katherine Plass, Department of Chemistry

Obsidian, a volcanic glass commonly used to make prehistoric tools, can be analyzed for its major and trace elemental compositions, creating a “chemical fingerprint” for each unique volcanic eruption. Obsidian “fingerprints” can trace stone tools to their source volcano, which archaeologists use to define trading routes. A study in 2014 examined samples from the Mt. Taylor region of New Mexico using Portable X-Ray Fluorescence (pXRF). A goal of this current project is to compare data produced by the pXRF with data produced at F&M/ENE with our high-precision, lab-based wavelength dispersive XRF (WD-XRF) instrument. These results show that the pXRF analysis of trace elements had a tendency to be systematically lower compared to the lab-based WD-XRF instrument, suggesting that pXRF may not be a useful method for geochemical fingerprinting of obsidians. In addition, we are using these WD-XRF geochemical data to evaluate the geologic evolution of Mt. Taylor obsidians. This project was supported by funding from F&M's Committee on Grants Program.

Project Mentors:  Professors James Jolles and Robert Walter, Department of Earth and Environment

Previous research in the Plass lab has focused on copper sulfide nanoparticle synthesis and conducting anion exchanges on these nanoparticles, specifically selenium exchange. The purpose of conducting these selenium exchanges is to observe the selectivity of the nanoparticles and determine whether or not certain conditions are necessary to facilitate anion exchange successfully. Our research thus far has focused on characterizing the molecules formed within these reactions to determine why they cause selenium anion exchange, both using spectroscopy and computational modelling. This semester, our goal is to synthesize diselenide molecules using varying alkyl precursors to examine the effect on selenium exchange. Molecular dynamics calculations mimicking these in-lab experiments will be conducted and compared to in-lab results to see what molecules are formed. This project was supported by funding from F&M's Committee on Grants Program and the National Science Foundation.

Project Mentor:  Professor Katherine Plass, Department of Chemistry

This project investigates the activities that individuals engage in immediately after experiencing social rejection, exclusion, or ostracism. We hope to determine the frequency with which people spontaneously respond to social threats by enacting behaviors to repair the broken social bond, feel connected to others, distract themselves, feel better hedonically, or withdraw. Further, we examined myriad individual differences to determine what factors predict a certain response tendency. Our finding found that participants who sought reconnection or reflected on their rejection reported moderate levels of anxiety post-rejection. Meanwhile, seeking others was associated with lower anxiety, higher self-esteem, and reduced attachment anxiety and avoidance. Higher resilience was associated with revenge-oriented responses, while individuals with high rejection sensitivity showed a greater likelihood of social withdrawal. These findings pave pathways for future research within the realm of social rejection studies.  This project was supported by funding from F&M's Committee on Grants Summer Scholars Program.

Project Mentor:  Professor Megan Knowles, Department of Psychology

Thioethers, molecules containing two carbon-sulfur bonds, have applications in organic synthesis, biochemistry, and materials chemistry. The Tasker lab recently discovered a new way of making these products with good yields by reacting a thiophenol with an alkene, using a hypervalent iodine reagent. This reaction is an example of the thiol–ene reaction which can occur from a variety of catalysts including metal catalysts and photoinitiators. Hypervalent iodine reagents provide a more attractive route for the synthesis of thioethers as they are environmentally friendly, metal–free, and relatively inexpensive. Additionally, hypervalent iodine reagents are typically used as oxidants but can also participate in addition/reductive elimination pathways or radical pathways. We propose that the hypervalent iodine reagent undergoes ligand exchange with thiophenol in our mechanism. This past year, we have been focused on optimizing our thioether synthesis, investigating the mechanistic role of the hypervalent iodine reagent, and expanding the scope of the reaction. This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Sarah Tasker, Department of Chemistry

Significance: An individual smoker’s behavioral economic profile and varied warning messages can influence the perceived effectiveness of a message. Methods: Individuals completed behavioral economic tasks. They were then randomly assigned to view 1 of 4 message conditions (or a control) 3 times over the course of 10 days via a Prolific. Linear mixed effect models evaluated the impact of message type and assessment time on perceived message effectiveness (PME) Results: A time by message condition interaction was observed, p<.001.Messages with a short-term gain framing showed the lowest PME compared to other active messages, p=.04 main effect of message type. Models including all behavioral economic variables found that higher delay discounting for gains, p=.03, and lower demand intensity for cigarettes, p=.04, were associated with increased PME. Conclusion: Rather than treating smokers as a monolith, careful attention to variability among smokers could aid in more targeted messaging to facilitate behavioral change.  This project was supported by funding from F&M's Committee on Grants Summer Scholars Program.

Project Mentor:  Professor Hollie Tripp, Department of Government and the Public Health Program

This project examines the behavioral and ecological correlates of the gut microbiome in wild chickadees. I analyzed fecal samples collected from black-capped chickadees (Poecile atricapillus) overwintering in south-central Michigan between 2021 and 2023 to determine gut microbial diversity and examined whether gut microbiome diversity varies as a function of individual behavior and sex. Molecular sexing was performed as part of an effort to understand whether sex influences gut microbial diversity. In birds, sex is determined by the specific combination of sex chromosomes that an individual possesses, with females having one copy of two different chromosomes (W and Z), and males having two copies of a single chromosome (Z). By amplifying a region of the CHD gene which typically differs in length between the Z and W chromosomes, the combination of sex chromosomes an individual has can be assessed. This study will contribute new knowledge about how the gut microbiome functions in wild avian populations. This project was supported by funding from F&M's Committee on Grants Summer Scholars Program.

Project Mentor:  Professor Kelly Hallinger, Department of Biology

Here, we present paleoecological research in the Appalachian Piedmont region in southeastern Pennsylvania at Great Marsh, a late Pleistocene to Holocene freshwater wetland that became established in a formerly periglacial environment. A key goal of this study is to examine the stability of the spring-fed, valley-bottom ecosystem in the context of spatiotemporal changes in climate and vegetation. Subsurface sediment cores were extracted and were subsampled at 1-cm intervals for loss-on-ignition (LOI) analysis, radiocarbon dating, and plant macrofossil identification. Calibrated radiocarbon dates on fragments of unburned wood at depths of ~100 to 50 cm indicate rapid sedimentation during the early Holocene. Plant macrofossils, primarily seeds, were extracted from each 1-cm subsample through wet sieving and identified under a microscope using reference libraries. Obligate wetland species were dominant throughout the core. This work indicates long-term resilience and stability of the valley-bottom wetland ecosystem at Great Marsh throughout the Holocene.  This project was supported by funding from F&M's Committee on Grants Summer Scholars Program.

Project Mentor:  Professor Dorothy Merritts, Department of Earth and Environment

Alpine lake ecosystems are highly sensitive to environmental change. Here, we present preliminary results from two on-going projects. Project 1: To restore native fish communities, nonnative fish are often removed through the application of rotenone, an organic chemical agent that is toxic to organisms with gills including freshwater zooplankton. Zooplankton produce diapausing eggs and have an egg bank that accumulates in the sediment. These eggs can remain viable for many years which is crucial to allow their population to recover quickly after the use of rotenone. Our preliminary experiments demonstrated that warmer incubation temperatures result in faster egg development and an earlier termination of diapause. We are currently testing how rotenone impacts the viability of zooplankton diapausing eggs. Project 2: Many alpine lakes are being impacted by changes in inputs from rapidly-melting glaciers. We are quantifying seasonal changes in methane concentration in glacial and non-glacial lakes. This project was supported by funding from the F&M’s Committee on Grants Summer Scholars Program and the Kayal Memorial Scholarship McDermott Endowment.

Project Mentors:  Professors Janet Fischer and Mark Olson, Department of Biology

Modifying nanoparticles can lead to solutions that solve the long-term problems in solar energy systems or help with infrared cancer treatments. Using cation and anion transformations, the chemistry and properties of nanoparticles can be altered. Recent work has demonstrated how Se anion exchange of the nanoparticles can be controlled depending on the amount of Cu2-xS present. Here we will explain the integration/deposition of selenium in the presence of different stoichiometric ratios of cadmium sulfide and copper sulfide. Though issues presented themselves, it was found that the properties of the nanoparticles differed depending on the amount of cadmium which was incorporated into the particles. Not only did the properties differ, but the regioselectivity and the rate that the selenium anions would incorporate into the nanoparticles changed depending on how much cadmium was present. These findings highlight the tunability of nanoparticle properties through controlled cation and anion exchange.  This project was supported by funding from the F&M’s Committee on Grants Program.

Project Mentor:  Professor Katherine Plass, Department of Chemistry

The present study aimed to answer whether the presence of humans with dogs will affect the frequency of sightings of white-tailed deer and gray squirrels on trails, specifically whether they spend less time through temporal avoidance. Twenty motion-activated trail cameras were placed around Spalding Conservancy for data collection. The collected images are processed through a series of machine learning models for sorting, which will then be classified to species by hand. These processed images will be used to determine the amount of people walking their dogs as well as the overall activity of the mammals that live in Spalding around these specific paths. I hope to present findings testing whether a higher level of dog activity leads to reduced presence of white-tailed deer and squirrels. Additionally, I predict an even greater impact on wildlife as the ratio of unleashed than leashed dogs increases.  This project was supported by funding from the F&M’s Committee on Grants Program.

Project Mentor:  Professor Daniel Ardia, Department of Biology

Non-canonical amino acids (ncAA) have the ability to assess a protein’s local environment and alter its function. The heme-nitric oxide and/or oxygen binding domain (H-NOX) from Caldanaerobacter subterraneus (Cs) contains a tyrosine at site 140 (Y140), which has been shown to influence diatomic gas (O2, NO, CO) binding affinities through hydrogen bonding networks surrounding the heme. Here, we describe our work to use a variety of ncAA tyrosine analogs designed to alter the pKa of the phenolic hydrogen at site 140 to tune gas binding affinity. This project was supported by funding the F&M’s Committee on Grants Program and the National Science Foundation.

Project Mentor:  Professor Christine Piro, Department of Chemistry

Hepta: The Mind’s Prism is an ambitious narrative short film project that seeks to explore the intricate dynamics of perception, control, and freedom within a fragmented society. By employing a dystopian and surrealistic lens, the film aims to dissect both the psychological and societal impacts of a segmented social structure. This exploration is particularly relevant in contemporary discourse, where issues of societal division, authoritarianism, and the manipulation of reality are increasingly pertinent. Hepta: The Mind’s Prism adopts an experimental narrative structure that eschews linear storytelling in favor of a more fragmented and layered approach. By fragmenting the narrative, the film allows for a multifaceted exploration of its themes, providing viewers with a non-linear journey that reflects the complexity of perception and control. The visual aesthetics of the film are meticulously crafted to enhance the surreal experience. Each scene is designed with symbolic imagery to convey deeper meanings beyond the surface narrative.  This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Jeremy Moss, Department of Visual Arts

This study examines how the COVID-19 pandemic influenced the endorsement of racial stereotypes among Franklin and Marshall College students, focusing on perceptions of Asians, Blacks, Latinx, and Whites. Using survey data from 2017, 2020, and 2023, the analysis tracks changes in negative, non-negative, and model minority stereotypes across different racial and class groups. Findings show a notable decline in negative stereotypes about Asians and Blacks during the pandemic, potentially linked to rising awareness from anti-Asian hate incidents and the Black Lives Matter movement. Despite expectations, reduced social contact did not significantly affect stereotype endorsement. Model minority stereotypes about Asians remained consistent, suggesting a persistence of positive discrimination. Patterns varied by group, with freshmen and White students displaying distinct shifts. Overall, the study reveals how social crises can both challenge and reinforce racial stereotypes, emphasizing the need to consider contextual factors in understanding intergroup perceptions. This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Katherine McClelland, Department of Sociology

As weather patterns become increasingly variable due to climate change, the warm months of temperate climates have experienced an increased frequency of cold snaps, or short periods of cold temperatures during warming months. For tree swallows (Tachycineta bicolor), who rely on warm temperatures to induce the flight of aerial insects, their main food source, this means periods of low food during breeding months, and less food for nestlings. By observing changes in parental feeding rates and differences in nestling growth rates during periods of natural or simulated cold snaps (through artificial nest box cooling), we aimed to explore the behavioral and developmental responses of tree swallows in Ithaca, New York. Parental feeding rate was measured through RFID triggers by banded adults. Growth rate was estimated through repeated measurements of wing length, head-bill length, and bird mass in nestling birds. This project was supported by funding from the National Science Foundation.

Project Mentor:  Professor Daniel Ardia, Department of Biology

Recently a new concept in rigid origami vertex theory was developed: That every rigidly foldable degree-4 origami vertex C has a dual vertex C' that has essentially the same kinematics as C. Furthermore, these two vertices can be combined to make a rigidly flexible non-manifold vertex CUC'. In this work we investigate rigid origami vertex duality in two ways: (1) we seek to determine what conditions will force the combined vertex to self-intersect when folding, and (2) expanding this duality concept to vertices of higher degree. This project was supported by funding from the National Science Foundation.

Project Mentor:  Professor Thomas Hull, Department of Mathematics

Although Great Marsh is one of Pennsylvania’s few remaining examples of a relatively unaltered pre-historic wetland ecosystem, which has existed continuously for ~11,200 years, there is little understanding of its origins. One hypothesis is that the secondary porosity of highly fractured bedrock underlying and surrounding the marsh yields a high groundwater flow rate. The bedrock is Precambrian gneiss, which generally is not thought to yield high rates of groundwater flow; however, prominent springs do exist within the marsh. Therefore, I investigated bedrock composition, fracture spacing and orientation, and groundwater springs to evaluate the origin and occurrence of groundwater that has supported a marsh throughout the Holocene. My observation is that the water that supports the marsh ecosystem is associated with springs emitted along prominent bedrock fractures. Understanding the origins of this landscape is highly relevant to modern wetland and floodplain restoration. This project was supported by funding from Moss Geology Field Work Fund.

Project Mentor:  Professor Dorothy Merritts, Department of Earth and Environment

Lancaster County, PA, ranked 8th in the nation for poor air quality, faces significant challenges from elevated concentrations of atmospheric particulate matter (PM2.5, PM10). These fine particles are linked to respiratory diseases, including asthma and COPD. This study undertook an assessment of aerosol pollution sources using particle compositions. Fine particles were captured on 3μm filters using a continuous air sampler pumping at 9x10⁻⁴ m³s⁻¹. Their elemental compositions were analyzed with a Scanning Electron Microscope (SEM) fitted with an Energy Dispersive Spectrometer (Hitachi SU 3900). Spot analyses identified particles enriched in Si, K, Na, Mg, Al, S, Fe, C, Zn, Mo, Br, and Ba. Principal Component Analysis (PCA) identified possible pollution sources: particles enriched in Si, Al, and K suggest silicate dust, whereas Mg, Ca, and S align with incineration of gypsum in construction debris, and Fe, Mn, Co, and Zn could be from vehicular traffic (fuel combustion and break-pad dust).and regulatory enforcement. This project was supported by funding from F&M's Committee on Grants Program and the Richard & Dorothy Foose Endowment.

Project Mentor:  Professor Robert Walter, Department of Earth and Environment

The Piedmont Province of the Mid-Atlantic region (MAR) underwent dramatic ecological changes during the last deglaciation and early Holocene, as warming triggered northward plant dispersal and ecological succession from boreal to temperate hardwoods. Organic-rich, river-wetland corridors expanded throughout the MAR, suggesting changes to valley bottom landscapes. This Pleistocene-Holocene transformation offers a potential paleo-analogue for the impact of global warming in northern latitudes. Recently discovered river-wetland corridors along the Little Conestoga Creek (LLC) provide a continuous Holocene record. We present a preliminary paleoenvironmental reconstruction of the Pennsylvania Piedmont Lowlands through analysis of fossil pollen from LCC. Bayesian age-depth models using 15 radiocarbon dates provide strong chronological control for the pollen record. Preliminary pollen analysis captures a Spruce-Pine dominated boreal environment during the Younger Dryas, transitioning to hardwood forests by around 8.2 ka. The Pleistocene-Holocene pollen documents the development of Holocene MAR valley bottoms, a potential analogue for high latitude “greening”. This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Adam Benfield, Department of Earth and Environment

Post-synthetic transformation enhances nanomaterials' complexity with minimal structural changes. Selenium anion exchange, a recent technique, creates metastable copper selenide phases from non-stoichiometric copper sulfide nanoparticles. Didodecyl diselenide is the key reagent driving sulfur-to-selenium exchange, while other diorganyl diselenides fail to induce transformation. This prompted computational analysis of carbon-selenium and selenium-selenium bond dissociation energies. Using the Amsterdam Modeling Suite, potential energy scans, molecular dynamics, and surface chemistry simulations were conducted to identify decomposition pathways. A reactive force field (ReaxFF) was derived from Amsterdam density functional (ADF) calculations to ensure accurate bond angles and lengths. Comparing ReaxFF with density functional calculations helps determine which diorganyl diselenides enable anion exchange. Understanding decomposition pathways and reaction intermediates is crucial for designing greener selenium transformations and advancing chalcogen anion exchange research. This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Katherine Plass, Department of Chemistry

This research systematically examines over 200 academic papers to explore how institutional voids and social networks shape business environments, particularly in emerging markets. By synthesizing existing literature, we highlight key gaps and provide insights into how businesses navigate weak formal institutions using alternative approaches, such as social connections and informal networks. We also worked on developing a comprehensive case study on The Chaudhary Group, a multinational conglomerate based in Nepal, to illustrate these concepts in practice. Based on interviews, reports, and articles, this case study offers a real-world perspective on overcoming business obstacles in underdeveloped institutional settings. Our findings contribute to international business discussions and serve as valuable teaching resources for undergraduate courses. Ultimately, this work deepens understanding of institutional voids and provides practical strategies for businesses operating in challenging environments. This project was supported by funding from F&M's Committee on Grants Summer Scholars Program.

Project Mentor:  Professor William Schneper, Department of Business, Organizations and Society

Climate change is harming numerous ecosystems including coral reefs, which are based on a symbiosis between corals and algae. Coral bleaching, which is destroying reefs worldwide, represents the loss of this symbiosis, and whether reefs can survive depends on rapid adaptation of the symbiosis to higher temperatures. In this study, I am examining a mutation (Met228Thr) in the phosphoglucose isomerase enzyme (PGI) which arose from a previous study after symbiotic algae were exposed to high temperature for four years. I hypothesize this mutation will allow the protein to function better at elevated temperatures. To test the hypothesis, I have produced recombinant wildtype and mutant PGI to compare Arrhenius Break Temperature (the temperature at which the enzyme loses function) of the two forms. Significant stabilization of the warm-adapted mutant enzyme could suggest that rapid adaptation of the symbiosis is possible.  This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Peter Fields, Department of Biology

Coral bleaching, which is decimating tropical reefs around the world, occurs when corals, stressed by factors like warmer sea surface temperatures (SSTs), expel symbiotic algae. We hypothesize that the coral is heat resistant compared to the algae, which is the reason that algae are expelled. The survival of coral reefs, then, depends on the ability of the coral-algal symbiosis to adapt quickly to rising SSTs. A previous study showed that algae in the lab evolved to survive higher temperatures, and this higher tolerance was correlated with a mutation (M228T) in phosphoglucose isomerase (PGI) in an area of the molecule associated with catalytic motions. To determine whether this mutation provides greater thermostability, I am testing the activity of wild-type and mutant PGI. Results will help us determine if the mutant PGI is more heat resistant, which would suggest that adaptation in the algae to prevent coral bleaching is a possibility. This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Peter Fields, Department of Biology

My research is on the role that chimney sweepers played in nineteenth century England. Chimney sweeps held an interesting place in society, at once held in respect for the purported Luck they could grant, and reviled as dirty and gross, both literally and morally. Sweeps’ Luck meant that sweeps were often guests of honor at weddings, and people would bow to them when passing on the street. Additionally, sweeps often led May Day revelling in English cities; the day was sometimes dubbed “Sweeps Day.” Feasts were also held for them. However, the continued usage of child labor led sweeps into ill repute. Widespread efforts to eradicate the use of child labor due to its high injury and mortality rates often vilified sweeps as physically dirty and morally repugnant. Chimney sweeps therefore occupied a position of great ambiguity in England and fit in with the archetype of the “dirty job”. This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Ben McRee, Department of History

Sugar metabolism is a universally shared metabolic pathway, and all known organisms employ an electron gradient to generate ATP. The enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) stands at the intersection of these two pathways, catalyzing an important step in the conversion of glucose to pyruvate and producing the essential electron carrier NADH. In addition to its catalytic role, GAPDH appears to act as a sensor for assessing the status of the cellular oxidative state. A particular active-site cysteine residue is critical to both roles. The crystal structures presented here shed light on both oxidation of this residue and on its intentional modification by covalent inhibitors. Both wild-type and C152S mutants of recombinant human GAPDH have been crystallized. WT GAPDH has been crystallized in the presence and absence of reducing agents and with covalent inhibitors such as 3-bromopyruvate. This suite of crystal structures illustrates the structural consequences of the oxidation and covalent modification of the essential active-site cysteine residue of GAPDH. This project was supported by funding from F&M's Committee on Grants Program.

Project Mentor:  Professor Gabriel Brandt, Department of Chemistry

N Recent studies in our group of of [(Cymene)RuCl₂(L)] complexes (L = monodentate N- or P-donor ligand) have discovered how ligand substituents influence electron transfer (ET) processes in these complexes, including on the potential required for ET and the subsequent chemical reactivity initiated by these ET processes. We have now extended our exploration to [(p-cymene) RuCl2(1-Im)] and [(p-cymene) RuCl2(3-pyr)] complexes containing 1-substituted imidazole (1-Im) and 3-substituted pyridine ligands (3-pyr) and have studied the effects of the ligand substituents on ET processes in the complexes supported by these platforms . As we hypothesized, the potential required for ET in these complexes potential was tuned by the ligand substituents; in CH3CN, ET also resulted in generation of a new product A, whose potential was also affected by the ligand substituents. The ET profile of these complexes and the comparison of the substituent effects across our various family of complexes will be discussed.  This project was supported by funding from F&M's Committee on Grants Summer Scholars Program.

Project Mentor:  Professor Davide Lionetti, Department of Chemistry