Biochemistry Commons^™

Diets And Environmental Impacts - Generational Outlook, Aspen Hopper, Melanie Jex

Student Research Symposium

How different diets impact the environment: Are we aware?

Determining The Kinetic Basis Of Crispr-Cas12a2 Function, Sobita Kunwar, Thomson Hallmark, Dylan Keiser, Bronson Naegle, Sudeshna Manna, Aaron Thomas, Chase L. Beisel

Student Research Symposium

CRISPR- Cas (Clustered Regularly Interspaced Short Palindromic Repeats- CRISPR associated) systems are bacterial adaptive immune systems that protect bacteria against mobile genetic elements such as viruses and plasmids^1,2.

Solving The Structure Of An Ancestral Protein Tyrosine Phosphatase, Natalie Turcsanski, Edna Armah

Student Research Symposium

Protein tyrosine phosphatases (PTPs) regulate cell signaling by removing phosphate groups from tyrosine residues. Malfunction of these enzymes can lead to diseases such as diabetes and cancer. A conserved feature among PTPs is the catalytic acid loop, essential for phosphate removal. Computational analysis of PTP structures revealed that ancestral PTPs have considerable variation in conformations of this loop, sparking interest in their further study. The Asgard group, identified as ancestral to eukaryotic PTPs, was successfully expressed and purified under optimized conditions. Current efforts focus on optimizing crystallization to obtain larger crystals for structural analysis. This project will investigate the allosteric …

Determining The Function Of Type Iv-B Crispr-Cas Systems, Eric Jenkins, Brendon Guinn

Student Research Symposium

CRISPR-Cas systems are a diverse group of prokaryotic adaptive immune systems that defend against Mobile Genetic Elements (MGEs) such as bacteriophages and plasmids. CRISPR-associated (Cas) proteins bind to guide RNAs (crRNAs) transcribed from a DNA repeat array (CRISPR array) containing spacers complementary to MGEs. Upon infection by a MGE, the Cas protein-crRNA complex binds to the target sequence in the invaders genome and cleaves the nucleic acid.

Metabolite Analysis To Understand Factors Limiting Microbial Fermentation At High Substrate Concentrations, Bishal D. Sharma

Dartmouth College Ph.D Dissertations

Clostridium thermocellum, a thermophilic anaerobic bacterium, holds promise as a biocatalyst for conversion of lignocellulosic biomass into biofuels. This microbe has been subjected to various metabolic engineering strategies, including the deletion of genes encoding secondary fermentation products such as H₂, formate, acetate, and lactate, as well as the expression of heterologous genes to redirect carbon flux toward ethanol production. Despite these efforts, achieving economically viable ethanol titers remains a challenge. We hypothesized that studying how intracellular metabolite concentrations change as fermentation stops could reveal metabolic bottlenecks or regulatory mechanisms limiting ethanol production at high titers. However, metabolomics studies at …

Biochemical And Structural Insights Into The Yersinia Effector Yopm And Its Negative Regulation Of The Pyrin Inflammasome, Bethany Wairimu Mwaura

Dartmouth College Ph.D Dissertations

Bacteria utilize sophisticated secretion systems to inject effectors into host cells in order to facilitate their survival and replication in the host. Some pathogenic species of Gram-negative bacteria use a conserved contact-dependent T3SS to inject a wide array of effectors. While the effectors diverge in their structures, functions and cell-localization, the T3SS is well conserved. Several effectors discussed in this thesis target key host inflammasome responses. The focus of this work is how the Yersinia effector YopM inhibits the pyrin inflammasome. During Yersinia infection, two effectors, YopE and YopT inadvertently activate the pyrin inflammasome while targeting RhoA to avoid phagocytosis. …

Metabolic Transitions In Embryos Of Artemia Franciscana: Regulation And Consequences For Oxidative Stress, Daniel Anthony Arabie

LSU Doctoral Dissertations

Embryos of Artemia franciscana survive harsh conditions in diapause and anoxia-induced quiescence for years by undergoing deep metabolic transitions. I investigated the relationship between phosphorylation of pyruvate dehydrogenase (PDH) and carbon flux to the tricarboxylic acid (TCA) cycle during metabolic depression. The difference in catalytic activity of the PDH complex (PDC) in maximally phosphorylated and dephosphorylated samples was 16.5-fold. Western blot analysis confirmed the changes in phosphorylation of PDH. Analysis of PDH expression in diapause and post-diapause embryos via phospho-PDH showed no significant differences. Investigation of post-diapause embryos under anoxia showed that phosphorylation of PDH decreased and activated the enzyme. …

Toward Ar Visualization Of The Fluid-Mosaic Model Of The Cell Membrane, Yoonwoo Lee, Allison Ost, Junghyuk Lee, Krisztina Z. Bencze

SACAD: Scholarly Activities

Background: During the first semester of biochemistry experience, students focus on learning the structure and function of biomolecules: carbohydrates, lipids, proteins, and nucleic acids. Visualizing these structures and understanding interactions between molecules helps students better understand biological function. A variety 3D visualization tools are available, ex. PyMol, Chimera, Avogadro, Blender. Within the past decade, Augmented Reality (AR) and Virtual Reality (VR) applications gained more popularity. VR with its immersive visual experience is more sought-after, but the higher cost and the need for headset creates limitations in the classroom. AR visualizations are cheaper and more accessible, several publications report successful implementation …

Host P53 Expression During C. Parvum Infection…Does The Virus Play A Role?, Jasdeep Kaur Dhanoa

Biochemistry and Molecular Biology

C. parvum infection induces significant host cellular stress responses, particularly through the modulation of p53 expression underscoring its potential involvement in gastrointestinal malignancies. Understanding these mechanisms is crucial for developing targeted therapeutic interventions. This study investigated the effects of C. parvum infection on host p53 dynamics in HCT-8 cells and assessed the impact of antiviral agents Lamivudine and Amantadine on the virus CSpV1 present within the parasite C. parvum. Further, the study focuses on whether the p53 effect changes with the presence or absence of CSpV1. The p53 assay results showed a constant increase in p53 activity after infection of …

Kinetic Control And Trapping In The Supramolecular Polymerization Of M-Terphenyl Bis-Urea Macrocycles, Sophya V. Garashchuk, Gamage Isuri P. Wijesekera, Isabella G. Rushton, Vaibhavi A. Samant, Fahidat A. Gbadamosi, Dr. Md Faizul Islam, Sophya V. Garashchuk, Prof. Dr. Linda S. Shimizu

Faculty Publications

Herein, we examine pathway complexity in the supramolecular polymerization of a novel m-terphenyl bis-urea macrocycle. Designed to induce kinetically metastable states, the macrocycle‘s concentration-dependent aggregation was studied via 1H NMR and IR spectroscopy in THF and CHCl₃. Temperature-dependent UV-Vis spectroscopy in water/THF revealed a cooperative nucleation-growth mechanism, indicated by a shift in λmax to longer wavelengths upon cooling. Morphological studies using DLS, AFM, and SEM demonstrated fibrous aggregate formation. Thermal hysteresis observed in assembly-disassembly cycles indicated kinetically trapped species, with cooling governed by kinetic control and heating by thermodynamic processes. Deviations in ΔH values during cooling, compared to van′t …

Investigation Of The Effects Of The Peptidylarginine Deiminase Inhibitor Cl-Amidine On Apoptosis And Gene Expression In Ovarian Cancer, Victoria Walden

Longwood Senior Thesis Proposal

Peptidylarginine deiminases (PADs) are a family of enzymatic proteins responsible for the conversion of arginine and methylarginine residues to citrulline. This conversion is important for several key cellular processes including transcriptional gene regulation. Recently, a link has been established between overexpression of a particular PAD, PAD4, and the accelerated progression of both autoimmune diseases and cancers. Ovarian cancer exhibits heightened levels of PAD4 in affected cells. High levels of PAD4 are associated with the formation of neutrophil extracellular traps (NETs) that promote cancer metastasis, and downregulation of the p53 apoptotic pathway. Thus, it is important to explore inhibitors of PAD4. …

Next-Generation Biomedical Implants And Stimuli Responsive Soft Optical Arrays Via Surface Functionalized Elastomeric Materials, John M. Kapitan

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The demands of emerging technologies, such as soft robotics, stretchable electronics, and next generation biomedical implants, has led to the development of diverse polymeric and hybrid organic/inorganic materials specifically tuned to meet these challenges. These materials typically have low Young’s moduli and are inert with high chemical stability. However, this has led to materials that are static in nature, lacking any meaningful way of responding to changes in their environment and adapting to these changes. This has driven a shift towards the design, manufacturing, and characterization of various stimuli responsive surfaces, relying on precise control of surface chemical coatings and …

Dental Disparities: An Analysis Of Dental Caries Risk Factors Promoting Disparities Between Rural And Urban Communities In Nebraska, Nick Lounsbery

Honors Program: Senior Projects (Public)

The prevalence of dental caries in the United States remains a public health concern, as it is one of the most common chronic conditions across people of all ages. Research shows that preventative measures including brushing, fluoridated water, and regular checkups are effective strategies to mitigate tooth decay. However, there appears to be a divide between rural and urban populations, as the presence of dental cavities is significantly greater in remote areas in the State of Nebraska. Research methods used in this analysis included analyzing accredited academic literature to illustrate how cavities form from a biochemical perspective. Research methods also …

Steroid Receptors And Coregulators: Dissemination Of Sex Differences And Emerging Technologies, Sally Pauss, Evelyn A. Bates, Genesee J. Martinez, Zane T. Bates, Zachary A. Kipp, Cassandra D. Gipson, Terry D. Hinds Jr.

Markey Cancer Center Faculty Publications

Steroid receptors are ligand-induced transcription factors that have broad functions among all living animal species, ranging from control of sex differences, body weight, stress responses, and many others. Their binding to coregulator proteins is regulated by corepressors and coactivators that interchange upon stimulation with a ligand. Coregulator proteins are an imperative and understudied aspect of steroid receptor signaling. Here, we discuss steroid receptor basics from protein domain structures that allow them to interact with coregulators and other proteins, their essential functions as transcription factors, and other elemental protein–protein interactions. We deliberate about the mechanisms that coregulators control in steroid receptor …

Expanding The Lexa Bacterial Two-Hybrid System For Human Protein-Protein Interaction Screening: Application To Tumor Suppressor Par-4, Rebecca M. Richardson

Chemistry & Biochemistry Theses & Dissertations

Protein-protein interactions (PPI) are fundamental to cellular function, influencing processes such as signaling, structural organization, and disease progression. Disruptions in PPIs are implicated in cancer and neurodegenerative diseases, highlighting their importance as therapeutic targets. However, traditional methods for studying human PPIs, such as yeast two-hybrid and co-immunoprecipitation mass spectrometry, are costly and technically demanding. This dissertation explores the LexA-based bacterial two-hybrid (LexA-B2H) system as a cost effective and accessible alternative for investigating human PPIs.

This study focuses on the interaction between glucose-regulated protein 78 (GRP78) and cleaved prostate apoptosis response-4 (cl-Par-4), a tumor suppressor protein involved in apoptosis and neurodegenerative …

Low Dissolved Oxygen Operation Enhances Biological Phosphorus Removal In Wastewater Treatment, Haley Morgan

Civil & Environmental Engineering Theses & Dissertations

Biological phosphorus (bio-P) removal occurs when bacteria are exposed to anaerobic/aerobic conditions that stimulate polyphosphate-accumulating organisms (PAOs) to uptake phosphorus. In most treatment plants, dissolved oxygen (DO) concentrations in the aeration tanks are commonly at or above 2.0 mg O₂/L, which is often referred to as the most optimal aeration condition for bio-P. If bio-P can happen efficiently at lower DO (< 0.3 mg O₂/L), then the energy demand of aeration can be decreased appreciably. This research was conducted in a biological nutrient removal (BNR) pilot plant to assess the performance of bio-P at progressively lower DO operation. This …

Functional Connectivity Of Red Chlorophylls In Cyanobacterial Photosystem I Revealed By Fluence-Dependent Transient Absorption, Sara Sohail, S. Sohoni, P.-C. Ting, L. R. Fantz, S. M. Abdulhadi, C. Macgregor-Chatwin, A. Hitchcock, C. N. Hunter, G. S. Engel, S. C. Massey

Chemistry & Biochemistry Faculty Works

External stressors modulate the oligomerization state of photosystem I (PSI) in cyanobacteria. The number of red chlorophylls (Chls), pigments lower in energy than the P₇₀₀ reaction center, depends on the oligomerization state of PSI. Here, we use ultrafast transient absorption spectroscopy to interrogate the effective connectivity of the red Chls in excitonic energy pathways in trimeric PSI in native thylakoid membranes of the model cyanobacterium Synechocystis sp. PCC 6803, including emergent dynamics, as red Chls increase in number and proximity. Fluence-dependent dynamics indicate singlet–singlet annihilation within energetically connected red Chl sites in the PSI antenna but not within bulk Chl …

Induced Mutagenesis In West Nile Virus Non-Structural Protein 3 With A Discussion Of The Mutation's Effects On Viral Properties, Caden Connealy

Honors Program: Senior Projects (Public)

West Nile Virus (WNV), a member of the Flaviviridae family and introduced to the Western hemisphere in 1999, presents a unique and emerging threat to human health. Infection in humans is often mild but can occasionally result in severe neurological impairment and even death. West Nile Virus non-structural protein 3 (NS3) plays an important role in the process of viral genome amplification. More specifically, the C-terminal domain of the protein folds into a helicase enzyme, which is responsible for the “unwinding” of double-stranded RNA intermediates and RNA secondary structure on the WNV genome. This is a vitally important step in …

Domain Communication In Bifunctional Proline Utilization A From Sinorhizobium Meliloti, Emma Bitterman

Honors Program: Senior Projects (Public)

The reduction potential of flavin bound to Sinorhizobium meliloti proline utilization A (SmPutA) is beneficial in providing vital information on enzyme activity and the active site environment. Flavin is crucial in biological metabolism such as aerobic respiration and other important processes like oxygen activation that are catalyzed by flavin-dependent enzymes. (4). In this study, we seek to determine whether the redox potential of SmPutA-bound flavin can be used to characterize potential long-distance communication and analyze the possibilities of inactivation reversibility. SmPutA is a large bifunctional enzyme that catalyzes the overall oxidation of proline to glutamate via two catalytic domains (1). …

Development, Optimization, And Validation Of A High-Sensitivity Capillary Zone Electrophoresis System For Bioanalytical Applications, Aaron I. Mena

Electronic Theses and Dissertations

Capillary zone electrophoresis (CZE) is a powerful analytical technique widely used for biomolecular separation due to its high resolution, efficiency, and sensitivity. This report presents the development and validation of a novel CZE system designed to improve modularity, reproducibility, and operational efficiency. The system integrates a laser-induced fluorescence (LIF) detection method with a 488 nm laser, enhanced fluid control through a negative pressure system, and a user-friendly GUI for automated operation and data acquisition. Performance verification included pressure stability tests, fluorescence accuracy assessments, and electrophoretic reproducibility studies. Comparative analysis with a previous CZE iteration confirmed improved baseline stability, peak resolution, …

Synthetic Protein Mimetic Based Therapies For Neurodegeneration, Nicholas H. Stillman

Electronic Theses and Dissertations

Protein-protein interactions (PPIs) are crucial for the regulation of a majority of, if not every fundamental cellular process. Despite their role in regular biological processes, dysregulated and/or aberrant protein-protein interactions (aPPIs) are often related to the onset of disease including cancer, viral infection, and amyloid diseases. aPPIs have historically been deemed ‘undruggable’ due to their large surface area and lack of a binding cavity; however, today, more than 40 disease-related aPPIs have been targeted with small molecules and several of those have reached clinical trials.

A class of synthetic protein mimetics called oligopyridylamides (OPs) has been shown to inhibit disease-related …

The Guanine Nucleotide Exchange Factor Ric-8a Regulates The Sensitivity Of Constitutively Active Gαq To The Inhibitor Ym-254890, Morgan Dwyer, Jiansong Luo, Tyson Todd, Kendall Blumer, Gregory Tall, Philip Wedegaertner

Department of Biochemistry and Molecular Biology Faculty Papers

Heterotrimeric G proteins are stimulated under normal circumstances by G protein-coupled receptors to promote downstream intracellular signaling. Mutations can occur in αq at glutamine 209 (Q209) that cause constitutive, G protein-coupled receptor independent signaling due to disruption of GTPase activity. Specifically, Q209L/P mutations are oncogenic drivers of uveal melanoma. YM-254890 (YM) has been shown to selectively inhibit both WT and constitutively active (CA) αqQ209L/P by preventing the release of GDP and exchange for GTP, thereby halting downstream signaling. Because αqQL/P are thought to be primarily GTP-bound and GTPase deficient, the current mechanistic understanding of YM inhibition needs further investigation to …

Synthesis Of A Series Of Rare-Earth-Based Multi-Anion Chalcogenide Iodides Re3Si2SeXS8-XI (Re = La, Ce, Pr, And Nd) Using The Flux-Assisted Boron-Chalcogen Mixture Method, Gopabandhu Panigrahi, Habiba Binte Kashem, Gregory Morrison, Hans Conrad Zur Loye

Faculty Publications

Single crystals and polycrystalline powders of rare earth mixed chalcogenide iodides La3Si2Se1.21S6.79I, Ce3Si2Se1.39S6.61I, Pr3Si2Se1.22S6.78I, and Nd3Si2Se1.18S6.82I were prepared using the reactive flux-assisted boron-chalcogen mixture (BCM) method at 850 °C. All compounds crystallized in the monoclinic crystal system, space group C2/c (space group number 15). The series adopts the La3Si2O8Cl structure type, containing isolated SiQ4 tetrahedra connected by REQ8 (RE = La, Ce, Pr and Nd) polyhedra; this arrangement creates tunnels that are filled by I atoms. The partial substitution of S by Se was carried out to modulate the optical properties. Phase pure samples and uniform solid solutions were obtained …

The Expression Profile Of The Rank/Rankl/Opg Pathway In Breast Cancer Stem Cells Isolated From Breast Cancer Cell Lines, Mohamed M. Kamal, Hassnaa H. Elgohary, Sherine Maher Rizk, Nadine H. Maurice

Pharmacy

The RANK/RANKL/OPG signaling pathway plays a crucial role in breast cancer progression and metastasis. However, its expression patterns and potential implications in breast cancer stem cells remain poorly understood. This study aimed to characterize the expression profile of this pathway in breast cancer stem cells isolated from two distinct breast cancer cell lines: MDA‐MB‐231 and MCF‐7. Mammospheres (MS), representing breast cancer stem cells, were generated using agar‐coated 6 well tissue culture plates in suitable mammospheres culture conditions. Flow cytometric analysis showed enrichment of the CD44+/ CD24− subpopulations in the mammospheres cultures, with MDA‐MB‐231 exhibiting a higher percentage compared to MCF‐7. …

Structural Basis For Intrinsic Strand Displacement Activity Of Mitochondrial Dna Polymerase, Ashok Nayak, Viktoriia Sokolova, Sirelin Sillamaa, Karl Herbine, Juhan Sedman, Dmitry Temiakov

Department of Biochemistry and Molecular Biology Faculty Papers

Members of the Pol A family of DNA polymerases, found across all domains of life, utilize various strategies for DNA strand separation during replication. In higher eukaryotes, mitochondrial DNA polymerase γ relies on the replicative helicase TWINKLE, whereas the yeast ortholog, Mip1, can unwind DNA independently. Using Mip1 as a model, we present a series of high-resolution cryo-EM structures that capture the process of DNA strand displacement. Our data reveal previously unidentified structural elements that facilitate the unwinding of the downstream DNA duplex. Yeast cells harboring Mip1 variants defective in strand displacement exhibit impaired oxidative phosphorylation and loss of mtDNA, …

Molecular Interaction Of Purple Rice Ferulic Acid And Skin Aging-Related Enzymes, Ernanin Dyah Wijayanti, Fatchiyah Fatchiyah, Anna Safitri, Dian Siswanto

Makara Journal of Science

Purple rice is rich in ferulic acid, a phenolic acid abundant in rice. Ferulic acid (FA) has long been recognized for its anti-oxidant properties, which are linked to its skin anti-aging activity owing to its ability to scavenge free radicals and pro-tect cells from damage. Skin anti-aging activity could be assessed by inhibiting skin aging enzymes. However, there was limited information on the mechanism of FA inhibition of these enzymes. This study focused on the molecular interac-tion between purple rice FA and collagenase or tyrosinase, both with and without their substrates. The interaction be-tween FA (CID 445858), collagenase (2Y6I), tyrosinase …

Biochemical, Structural, And Conformational Characterization Of A Fungal Ethylene-Forming Enzyme, Shramana Chatterjee, Joel A. Rankin, Mark A. Farrugia, Simahudeen Bathir J S Rifayee, Christo Z. Christov, Jian Hu, Et. Al.

Michigan Tech Publications

The ethylene-forming enzyme (EFE) from the fungus Penicillium digitatum strain Pd1 was heterologously produced in Escherichia coli and its properties were compared to the extensively characterized bacterial enzyme from Pseudomonas savastanoi strain PK2. Both enzymes catalyze four reactions: the conversion of 2-oxoglutarate (2OG) to ethylene and CO₂, oxidative decarboxylation of 2OG coupled to _L-arginine (_L-Arg) hydroxylation, uncoupled oxidative decarboxylation of 2OG, and the production of 3-hydroxypropionate (3-HP) from 2OG. The strain Pd1 enzyme exhibited a greater ratio of ethylene production over _L-Arg hydroxylation than the PK2 strain EFE. The uncoupled decarboxylation of 2OG and …

Mechanisms Of Macrophage Metabolic Activation And Paracrine Wnt Signaling In The Pathogenesis Of Systemic Sclerosis, Emily Ann Morris

Dartmouth College Ph.D Dissertations

Systemic sclerosis (SSc) is a chronic autoimmune disease of unknown etiology. We have previously shown that macrophages (MØs) play a critical role in its pathogenesis; however, the mechanisms driving MØ activation in SSc remain poorly understood. This dissertation investigates the molecular signaling pathways and biochemical mechanisms underlying profibrotic MØ activity in SSc.

First, I identify a novel MØ-specific effect of mycophenolate mofetil (MMF), the standard-of-care treatment for SSc. While MMF is a well characterized lymphostatic, my findings demonstrate that its active metabolite, mycophenolic acid (MPA), is also capable of directly inhibiting myeloid viability and profibrotic MØ activation by suppressing de …

First-In-Class Peptide Molecules Targeting The Mien1 Cancer Signaling Pathway, For Which No Inhibitors Have Been Identified To Date., Amit Tripathi, Jamboor K. Vishwanatha

Research Symposium

Background: Migration and Invasion Enhancer 1 (MIEN1) is a critical oncogene that drives cancer cell migration, invasion, and epithelial-to-mesenchymal transition (EMT) in various cancers. MIEN1 overexpression is linked to aggressive tumor progression and poor prognosis. Despite its established role in cancer biology, targeted therapeutic options remain unexplored. This study aimed to identify and characterize first-in-class therapeutic molecules targeting the MIEN1 signaling pathway to inhibit cancer progression.

Methods: To develop novel bio-active peptides, we leveraged conserved immunoreceptor tyrosine-based activation motif (ITAM) and prenylation motifs within the MIEN1 protein sequence. Using rational peptide design, we identified and synthesized bioactive peptides, namely LA3IK …

Nanostructure Retention To 1100 °C In Soft-Templated Niobium Tungstates Using Dual-Carbon Strategy, Sean C. Wechsler, Alexander Gregg, Coby S. Collins, Santosh Kiran Balijepalli, Morgan Stefik

Faculty Publications

Mesoporous metal oxides (MMOs) have diverse applications including energy storage, catalysis, and separation membranes. Block polymer structure directing agents enable the control of morphology and pore size, however preservation of the nanostructure is often limited to a narrow range of heat treatment temperatures which constrains the tailoring of defect chemistries. High temperature treatments typically lead to collapse of the porous structure as surface area is reduced during crystal growth. Here, using a mesoporous niobium tungstate it is shown that neither in situ carbon generation nor ex situ carbon infiltration alone enable preservation of the ordered mesostructure at temperatures high enough …