Biochemistry Commons^™

Modulation Of Electrophysiology And Plaque Aggregation In Huntington’S Disease Patient-Derived Cells By Picosecond Pulsed Electric Fields, Mackenzie A. Tardif-Kunk

Biomedical Sciences Theses & Dissertations

Huntington’s Disease (HD) is a fatal, autosomal dominant neurodegenerative disorder characterized by progressive motor and cognitive decline. Unstable expansion of cytosine-adenine-guanine (CAG) trinucleotide repeats in the huntingtin gene, often exceeding 35–40 repeats, results in an extended polyglutamine (PolyQ) tract in the translated protein. Abnormal folding of the mutant huntingtin (mHTT) protein leads to accumulation and aggregation within the cell, dysregulating various cellular processes through molecular sequestration. While several therapeutic strategies have been proposed, this disease remains incurable with treatments limited to symptom management.

Pulsed electric fields (PEF), primarily in the microsecond and nanosecond ranges, have been studied extensively for the …

Analysis Of The Atypical Temperature Dependence And Conformational Changes During Turnover Of A Lactobacillus Chlorogenic Acid Esterase, Nathaniel Carl, Yianni Tsigaris, Dan Ji, Nora K. Anpree, Kellie K. Omori, Cedric P. Owens

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Many bacterial chlorogenic acid esterases (ChlEs) exhibit atypical temperature behavior, featuring activities that barely change with temperature and activity maxima that fall below the thermal denaturation point. This work focuses on a ChlE from Lactobacillus helveticus (Lh–ChlE), which has a flat temperature dependence. First, it was determined that conformational changes during Lh–ChlE turnover are not rate-limiting and that the overall rate depends on the chemical step at all temperatures. Next, Lh–ChlE’s temperature dependence was investigated using a conformational equilibrium model that assumes the existence of a temperature-dependent equilibrium between an active and an inactive conformation and an activation heat capacity …

Effects Of Variable Light On Sexual Competition In Kelp Species, Jaycee Lanza

Master's Theses

As foundation species, kelps significantly influence the structure and composition of their surrounding habitat by modifying environmental conditions, including light levels, currents, nutrient availability, sedimentation, and seawater chemistry. Light, in particular, is a critical resource that varies greatly within kelp forests, affecting kelp reproductive processes such as gametogenesis, fertilization, and recruitment, which are vital to population persistence. Biological factors, such as density-dependent competition for resources and sexual competition with other kelps, can also affect such processes. To understand how environmental variables influence kelp populations, it is crucial to recognize their combined effects. This study investigated the impacts of light levels …

Mechanistic Determination Of Host Environmental Impacts On Shigella Virulence, Nicholas E. Dickenson

Funded Research Records

No abstract provided.

Fish Tissue Digestion And Microplastic Polymer Identification Protocol Using Open-Source Ftir Database, Shawn L. Kissinger, Vick-Ariel Privert, Jason Bystriansky, Kyle A. Grice

DePaul Discoveries

Microplastic (MP) contamination in aquatic ecosystems poses significant concerns for environmental and public health, as seafood represents a critical food source worldwide. Despite increasing evidence of MP presence in marine organisms, efficient and accessible detection methods remain essential for characterizing contamination patterns and informing regulatory frameworks. This study extracted MPs from brain, gill, intestine, liver, and muscle tissues of gilt-head bream (Sparus aurata) and European sea bass (Dicentrarchus labrax), two commercially important species from the Gulf of Cádiz, Spain, using a NaOH–HNO₃ chemical digestion protocol. Isolated particles were characterized by Fourier Transform Infrared (FTIR) spectroscopy, with …

Investigation Into Molecular Bases Of Pregnancy-Associated Malaria, Nicole Pozo

Biochemistry and Molecular Biology

Plasmodium falciparum causes the most severe and deadly form of malaria and remains a major global health problem, especially in sub-Saharan Africa (Milner, 2018). The parasite infects and multiplies inside red blood cells, leading to fever, anemia, organ damage, and death if untreated (Milner, 2018; Song et al., 2022). It is especially dangerous because it avoids the immune system by changing surface proteins called Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1), which are encoded by more than 60 var genes. By switching between these genes, the parasite hides from immune detection and creates repeated waves of infection (Deitsch & Dzikowski, …

Personalizable Metabolic Models To Enable Immune Characterization And Drug Discovery, Joshua Loecker

Department of Biochemistry: Dissertations, Theses, and Student Research

Cellular metabolism is reshaped by disease and physiological state, and genome-scale metabolic networks (GSMNs) offer a systematic way to interrogate this biology and identify therapeutic targets. Building a GSMN from expression data, however, requires a sequence of stages including read processing, normalization and gene-activity classification, multi-omic integration, model reconstruction, simulation, and biological interpretation. These are typically handled by disconnected tools spanning multiple programming languages, file formats, and databases. The resulting reliance on heterogeneous interfaces and manual steps threatens reproducibility. This work develops an ecosystem of computational tools that carry an analysis from raw sequencing reads to mechanistic biological interpretation. First, …

Recent Advances In Phosphatidylinositol Phosphate Kinases (Pipks) And Their Inhibitors, Mengxia Sun, Jian Hu, Xuefei Huang

BAU Journal - Science and Technology

Phosphatidylinositol phosphate kinases (PIPKs) are an important class of enzymes in humans, which produce lipid signaling molecules playing central roles in pathogenesis of diseases such as cancer, neurodegenerative diseases, and viral infection. Consequently, they are attracting increasing attention as drug targets for disease treatment. This review summarizes the functions of the PIPK family enzymes and highlights recent efforts on designing novel inhibitors against PIPKs. These advances are extensively discussed to stimulate interest in this field and promote further development of highly potent and selective inhibitors for innovative therapeutic applications.

Comparative Screening Of Cytotoxic Potential Of Berberis Aristata And Senna Alexandrina Extracts, Rida Noor Akhtar, Javaria Zahoor, Rizwan Ullah Khan, Aziz Ullah, Naila Malkani

Journal of Bioresource Management

Medicinal plants provide a safe and efficient source of drugs for cancer treatment. Berberis aristata and Senna alexandrina are traditionally used to treat several ailments because they contain compounds with antimicrobial, antitoxic, anti-inflammatory, and other properties. The objective of the study was to prepare crude ethanolic extracts of B. aristata and S. alexandrina and to determine their cytotoxic potential against cancer cells. Ethanolic extracts were prepared for both plants. Hepatocellular carcinoma cells (HepG2) were used for all assays. The cytotoxicity of extracts was determined by 3‑(4,5‑Dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide (MTT) assay using various concentrations of extracts. The obtained sub-lethal concentrations were used …

In Vitro Anticancer Evaluation Of Tamoxifen And Paclitaxel-Loaded Chitosan Nanoparticles Against Breast And Lung Cancer With In Silico Docking, Arshia Amaan, Farah Mehak, Amer Jamil, Fatma Hussain

Journal of Bioresource Management

Breast and lung cancer are the primary cause of death worldwide, underlining the need for an improved therapeutic strategy. In the current study, tamoxifen (TAM) and paclitaxel (PTX) loaded chitosan nanoparticles (NPs) were produced for the evaluation of sustained drug delivery and enhanced anticancer potential of nanocarriers over conventional chemotherapy against breast and lung cancers, respectively. Nanoparticles were produced by the ionic gelation method and characterized by UV-visible spectroscopy, Dynamic Light Scattering and Fourier Transform Infrared Microscopy (FTIR), verifying the nanoscale morphology, stability and successful encapsulation. A drug release profile study (in vitro) (78 %, 60-75 %) and …

Investigating Quinclorac Binding To Human Serum Albumin Using Spectroscopy And Molecular Docking, Le Nguyen, L. Hicks, L. Jodoin, S. Carby, D. S. Sanford, D. Benavides, A. Mishra, R. Yadav

Journal of the Arkansas Academy of Science

Human serum albumin (HSA) is the most abundant plasma protein and serves as a major transporter and reservoir for a wide range of endogenous ligands, including fatty acids, heme, bilirubin, prostaglandins, and metal ions, as well as numerous exogenous compounds, such as pharmaceuticals. HSA is a 66 kDa monomeric, multidomain protein containing two principal ligand-binding sites, Sudlow sites I and II. Sudlow site I contains Trp214, the sole tryptophan residue in HSA, whose intrinsic fluorescence provides a sensitive probe for studying ligand–protein interactions.

In this study, the interaction between HSA and the persistent organochlorine herbicide quinclorac (QNC) was investigated using …

In Silico And Toxicological Evaluation Of Crescentia Cujete Aqueous Extract: Potential Anticancer Activity Against Breast Cancer, Rahma Diyan Martha, Fatimah Fatimah, Syahputra Wibowo, Bantari Wisynu Kusuma Wardhani, Josephine Elizabeth Siregar, Elisabeth Farah Novita Coutrier, Alfia Fitrianita, Andri Pramesyanti Pramono, Ita Margaretha Nainggolan, Yudhi Nugraha, Danar Danar, Naufal Abiyyu, Lalu Unsunnidhal, Aswin Rafif Khairullah, Arif Nur Muhammad Ansori, Hesty Parbuntari, Wimbuh Tri Widodo

Makara Journal of Science

Majapahit plant (Crescentia cujete), commonly found in Indonesia, has not been extensively explored for its medicinal properties. Given that many cancer treatments are derived from plants, this study aimed to examine the effects of plants on cancer chemical composition of the C. cujete fruit pulp extract, identify its primary compounds, and assess its potential as an antioxidant, anticancer agent, particularly for breast cancer. An insilico approach was used to evaluate the toxicity and interactions, of the compounds with cancer biomarker proteins, in addition to an in vivo Brine Shrimp Lethality Test (BSLT) for BSLT, toxicity screening using six …

Rna G-Quadruplexes Function As A Tunable Switch Of Fus Phase Separation, Jenny L. Carey, Miyuki Hayashi, Emily A. Welebob, Laura R. Ganser, Huan Wang, Kerry Buckhaults, Jacquelyn A. Depierro, Zheng Shi, James Shorter, Sua Myong, Aaron R. Haeusler, Lin Guo

Department of Biochemistry and Molecular Biology Faculty Papers

Fused in sarcoma (FUS) undergoes liquid-liquid phase separation (LLPS) to support essential cellular functions, but aberrant phase transitions promote toxic aggregation in neurodegenerative disease. Short RNA oligonucleotides can reverse this behavior, yet the structural determinants that govern RNA activity remain poorly defined. Here, we identify RNA G-quadruplexes (rG4s) as tunable structural motifs that potently modulate FUS LLPS. rG4 activity depends on its concentration and is modulated by rG4 length and stability: increasing repeat number switches rG4s from inhibitor to nucleator of FUS assembly, whereas chemical modifications that stabilize rG4 enhance inhibitory function and render these activities resilient to ionic perturbation. …

Histone Deacetylases In Kidney Injury: Distribution, Injury-Specific Regulation, And Fibroblast Hdac1 Function, Huy Nguyen

ETDs from 2020-2029

Acute kidney injury (AKI) is increasingly recognized as a major contributor to the development of chronic kidney disease (CKD) through maladaptive repair and interstitial fibrosis. Epigenetic regulation has emerged as a critical factor of kidney injury responses, however the injury-specific and cell-type specific roles of histone deacetylases (HDACs) remain poorly defined. This dissertation investigates the regulation and functional significance of HDACs in kidney injury, with a particular focus on fibroblast HDAC1 as a mediator of interstitial fibrosis development following AKI. In my cisplatin-induced AKI model, a single dose of cisplatin caused a significant decline in kidney function in both male …

Main-Chain Ion-Pair Polybenzimidazole Membranes Enabling Reduced-Temperature Ht-Pemfc Operation (Down To 120°C), Brian C. Benicewicz, Huina Lin

Faculty Publications

Proton exchange membrane (PEM) fuel cells are promising for clean and efficient energy conversion across diverse applications. High-temperature PEM fuel cells (HT-PEMFCs) using phosphoric acid (PA)-doped polybenzimidazole (PBI) can operate up to 200°C, but at lower temperatures, water-induced PA loss often leads to performance degradation and reduced durability. In this work, we present a new class of main-chain ion-pair PBI membranes by integrating the imidazolium-biphosphate ion-pair units directly into the PBI backbone. This design results in membranes with high acid content, stronger acid-polymer interactions and stabilized acid retention. In single-cell tests, the Im+-PBI15-3 wt.% exhibits peak power densities of 0.79 …

Elucidating The Mechanisms Of Complex Flavoprotein Dehydrogenases, Tyler Alt

Dissertations

Flavins are ubiquitous redox active cofactors that can catalyze electron transfer between substrates. They offer the advantage of being able to stabilize a range of oxidation and protonation states, as well being amenable to covalent modification, which can further alter their activity. As such, the scope of reactions catalyzed by flavoproteins is broad and flavin has implications in a range of biological processes. The two predominant forms of flavin that serve as redox active cofactors are flavin adenine mononucleotide (FMN) and flavin adenine dinucleotide (FAD), which are functionally homologous. A major complication of studying flavoprotein dehydrogenases, and one that has …

Allosteric And Uncompetitive Inhibition Of Yeast Alcohol Dehydrogenase Identified By Enzyme Kinetics, Dylan Jeremy Harrison, Jenny A. Cappuccio

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

Enzyme kinetics is a powerful technique used to quantify the rate at which an enzyme converts a substrate into a product and to identify potential inhibitors. In this study, kinetic analysis was employed to assess the activity of yeast alcohol dehydrogenase (YADH) in the presence and absence of sweeteners commonly found in alcoholic beverages. YADH catalyzes the oxidation of ethanol to acetaldehyde using NAD⁺ as a cofactor; the reduction to NADH can be monitored spectrophotometrically at 340 nm. Based on structural similarities to the ribose moiety of NAD⁺, it was hypothesized that sucrose and sucralose could directly interact with the …

Structure-Based Discovery Of Malate Dehydrogenase Inhibitors With Efficacy Against C. Parvum Oocysts, Ankita Bharatbhai Kheni

Biochemistry and Molecular Biology

Cryptosporidium parvum, the etiological agent of Cryptosporidiosis (diarrheal illness) represents a significant global health burden, particularly affecting immunodeficient and pediatric populations. Since the parasite has a highly reduced mitochondrion and relies on glycolysis, enzymes such as C. parvum malate dehydrogenase (CpMDH), which are believed to be indispensable for parasite viability due to their pivotal roles in NAD⁺ regeneration and redox balance, remain largely unexplored as therapeutic targets. The present study employed a multifaceted experimental and computational strategy to evaluate the inhibitory activity of two lead-like and drug-like small molecules, referred to as compound 1.8 and compound 1.5, against the cofactor …

Terrestrial Abiotic Synthesis Of Simple Precursor Molecules Starting From Two Approaches: The Universality Of Carbon Reduction, Eloi Camprubi, Ben K.D. Pearce, Martina Preiner

School of Integrative Biological & Chemical Sciences Faculty Publications

To address the chemistry responsible for life’s emergence, we examine the simple chemicals accessible on early Earth and the processes that could have transformed them. We focus on carbon reduction as a process central to the direct precursors of life. Two main approaches for the emergence of life’s building blocks and their associated functions are discussed. One approach investigates chemical routes for forming life’s building blocks via processes that worked differently from those of extant life, referred to as “unrestricted” prebiotic chemistries. The other approach establishes a direct mechanistic connection between prebiotic building blocks and extant biochemistry, referred to as …

Chromatin Insulators Homie And Nhomie Can Interact With Distant Copies Either Together Or Separately, With Distinct Outcomes For Enhancer-Promoter Interactions, Miki Fujioka, Wenfan Ke, Paul Schedl, James B. Jaynes

Department of Biochemistry and Molecular Biology Faculty Papers

Chromatin insulators, a.k.a. boundary elements, separate regions of the chromosome with distinct chromatin characteristics, including distinct histone modifications. This activity affects gene expression by allowing chromatin domains to be stably regulated and maintained. Insulators also block enhancer-promoter interactions and, somewhat paradoxically, facilitate other interactions, particularly when they stitch together distant regions of the chromosome by pairing with specific partners. Here we explore how long-range interactions facilitated by insulator pairing are affected by the presence of two potentially competing partners. Our results show that when two partners are present, they can reduce each other's effects on distant gene expression, suggesting that …