Biochemistry Commons^™

The Synergy Between A Silver-Ruthenium Antimicrobial And Aminoglycosides Is Based On Severe Macromolecular Damage, Emmanuel Parkay Oladokun

Theses and Dissertations

The rise of multidrug-resistant (MDR) bacterial pathogens, including uropathogenic Escherichia coli (UPEC), highlights the urgent need for alternative treatment strategies to restore antibiotic efficacy. The silver-ruthenium antimicrobial AGXX exerts potent bactericidal effects through the production of reactive oxygen species (ROS); however, its potential synergy with antibiotics has not been thoroughly investigated. Here, we show that sublethal concentrations of AGXX strongly enhance aminoglycoside-mediated killing across a diverse panel of Gram-negative and Gram-positive MDR clinical isolates, including highly aminoglycoside-resistant strains. Combinational treatments significantly reduced the effective concentrations of gentamicin, tobramycin, kanamycin, and amikacin required to kill bacteria. Mechanistic analyses revealed that AGXX/aminoglycoside …

Interaction Of The Gram-Positive Human Pathogen Staphylococcus Aureus With Host Lipids, Sharanya Paul

Theses and Dissertations

Staphylococcus aureus is a prominent pathogen that is known to incorporate straight-chain unsaturated fatty acids (SCUFAs) into its lipids in addition to the normally biosynthesized branched-chain fatty acids (BCFAs) and straight-chain fatty acids (SCFAs). Furthermore, it has recently been shown that the incorporation of oleic acid into S. aureus lipids significantly enhanced the growth of the organism at low temperatures due to the greater fluidity imparted to the membrane. Together with others in the Wilkinson and Dahl laboratory, I have shown that low-temperature growth is enhanced by various SCUFAs, including the human antimicrobial fatty acids sapienic acid, linoleic acid, and …

Understanding The Fidelity And Specificity Of Dna Polymerase I, Bill R. Miller Iii, Andrew V. Yeager, Jake A. Collins, Alexis Blake, Elise Tate, Carol A. Parish, Eugene Y. Wu

Chemistry Faculty Publications

High-fidelity DNA polymerases employ complex mechanisms to catalyze template-dependent DNA synthesis while quickly discarding mismatches. Atomic-level structural details about short-lived states during nucleotide discrimination are necessary to gain insight into the kinetic checkpoints that contribute to fidelity. We performed microsecond molecular dynamics simulations of DNA polymerase I, large fragment, from Bacillus stearothermophilus (Bacillus fragment, or BF) in complex with a template guanine and a mismatched thymidine triphosphate to observe the early events in the process of selection against a mismatch. Although the nucleobases formed a wobble base pair early, the mismatched pair was blocked from fully entering the active site …

Discovery Of 5‑Chlorotryptophan-Containing Antibiotics Through Metabologenomics-Assisted High-Throughput Screening, Chantal D Bader, Isao Masuda, Angela Nichols, Edward Kalkreuter, Dong Yang, Thomas Christian, Yuko Nakano, Ya-Ming Hou, Ben Shen

Department of Biochemistry and Molecular Biology Faculty Papers

Actinomycetota bacteria have specialized in the biosynthesis of antibacterial natural products (NPs), and extract and fraction libraries made from those strains remain a promising source of NP drug leads. Herein, we present a high-throughput screen (HTS), based on engineered Escherichia coli strains expressing the human (Trm5) or bacterial (TrmD) m¹G37 tRNA methyltransferase, to discover NPs as novel anti-Gram-negative antibiotic leads. To harness the evolution of NPs with in vivo activity, the cell-based phenotypic HTS was applied to the Actinomycetota extract and fraction library at the Natural Products Discovery Center (NPDC), the Herbert Wertheim UF Scripps Institute for Biomedical …

Energetics And Kinetics Of Alkali Ion Exchange In Analcime, Jinyi Liu, An T. Ta, R. Seaton Ullberg, Jean Wilfried Hounfodji, Michael Badawi, Hans Conrad Zur Loye, Simon R. Phillpot

Faculty Publications

We employ density functional theory calculations to investigate the energetics and diffusion mechanisms of alkali metal ions (Na⁺, K⁺, Rb⁺, and Cs⁺) within the analcime framework. While Na⁺preferentially adsorbs at the center of the 8-member ring, DFT calculations show that larger ions, such as Cs⁺, occupy the center of the cage due to steric constraints. The computed exchange energies indicate that exchange of Na⁺by Cs⁺is thermodynamically favorable. Migration energy barriers, determined using the climbing image nudged elastic band method, show that Na⁺is …

Evaluating Bmx-001 As A Selective Radioprotector For Healthy Tissue In Pelvic Cancers, Molly Myers

Theses & Dissertations

Pelvic cancers, including rectal, anal, and prostate cancer, are relatively survivable cancers with high five-year survival rates, partially due to the addition of radiation to treatment regimens. Radiation confers excellent tumor control, but also causes damage to surrounding tissue, resulting in both short-term and long-term side effects. In a patient population that is surviving longer after treatment, limiting the impact of side effects is instrumental to improving patient quality of life. Radiation-induced ROS is instrumental in causing these side effects and provides a unique opportunity to protect healthy tissue from damage while sensitizing cancer tissue to treatment, as cancer cells …

Have You Had Your Vitamins Today? Development Of An Lc-Ms/Ms Method With A 100% Aqueous Gradient To Simultaneously Measure B Vitamins In Plasma From Study Participants In A “Greens” Nutritional Supplement Clinical Trial, Kennedy Brothers, Abigail Davis, Anna Losher, Yusra Ahmed, Sora Ghanem, Matthew J. Vergne

Student Scholar Symposium

This study assessed the absorption of key micronutrients from the multi-ingredient supplement using a novel developed LC-MS/MS method capable of analyzing B vitamins in a single run.

The study a randomized, double-blind, placebo-controlled crossover trial with 16 healthy participants (8 males, 8 females) to measure plasma nutrient appearance over 8 hours after supplement consumption. Serial blood samples were collected pre-consumption and at specified intervals post-ingestion. The novel LC-MS/MS method simultaneously quantified biotin, nicotinamide, pyridoxine, riboflavin, and thiamin in blood samples.

Results:The LC-MS/MS method had a range of 0.1 ng/mL to 1000 ng/mL and it proved to be robust and …

Structural Basis Of A Class Ii Ribonucleotide Reductase Found If Mycobacterium Tuberculosis, Leah Jacob

Student Scholar Symposium

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a leading global health challenge, particularly due to its ability to enter a dormant, drug-tolerant state that enables long-term persistence within the host. Just before dormancy, Mtb replicates its entire genome creating DNA precursors for when the infection reactivates. Ribonucleotide reductases (RNRs) play a critical role in bacterial survival by catalyzing the conversion of ribonucleotides into deoxyribonucleotides, a necessary step for DNA replication and repair. The class II RNR, NrdZ, has been implicated in facilitating Mtb persistence under hypoxic stress conditions, yet its structural and mechanistic function remains largely uncharacterized. …

Design, Synthesis And Biological Activities Of N-Substituted Phthalimide Derivative, Beaula Mangundah

Honors Theses

Phthalimides are a group of compounds among bicyclic non-aromatic nitrogen heterocycles that have gained recognition for their bioactivity across various fields, notably anti-cancer, anti-microbial, anti-oxidant, and anti-inflammatory. This study discusses the synthesis of a novel phthalimide derivative and provides an analysis of its biological activity. It was conducted through a Boric acid Imide synthesis and yielded a successful derivative using hexylamine. The product was evaluated in vitro for antimicrobial, anticoagulant, and anti-inflammatory properties using Kirby-Bauer disk diffusion, clotting time, hemolysis inhibition, and protein denaturation assays. It showed mild anticoagulant and anti-inflammatory activity.

Deciphering The Crl Code: Novel Mechanisms Of Canonical And Non-Canonical Ubiquitylation, Nicholas Wayne Purser

UNLV Theses, Dissertations, Professional Papers, and Capstones

Protein degradation is a fundamental process required for maintaining cellular homeostasis in eukaryotic organisms. In humans, distinct cell types exhibit unique proteomic landscapes that are dynamically balanced by the continual synthesis and degradation of proteins. The timely removal of damaged, misfolded, or old proteins is essential to permit new protein synthesis and to ensure proper cellular function.

Central to this regulatory network is ubiquitylation, a highly conserved posttranslational modification system that governs protein stability and function across all eukaryotic cells. Through the covalent attachment of ubiquitin molecules to protein substrates, this system modulates a broad range of biological processes, including …

The Dynamic Interplay Between Monovalent Salts And Ribosomal Protein S1 In Regulating Rna G-Quadruplex Structure, Chloe M. Martin

Honors Theses

Many remarkable discoveries, especially in the last decade, have shown scientists just how important RNA is. In this study, the secondary structure of RNA, G-Quadruplexes, is the topic of interest and how they are affected by salts and S1 protein. To obtain the S1 protein it was transformed from E. Coli using a bacterial plasmid. The S1 protein was then purified from the bacteria through the use of many purification methods. The monovalent cationic salts used were LiCl and KCl which have different ionic radii size that contributes to the stability of RNA G-Quadruplexes. This stability was observed and affected …

Structural Basis Of Panx1 Permeation And Positive Modulation By Mefloquine, Yangyang Li, Zheng Ruan, Junuk Lee, Ian Orozco, Edward Zhou, Juan Du, Wei Lü

Department of Biochemistry and Molecular Biology Faculty Papers

Purinergic signaling relies on ATP release through exocytosis and large-pore channels. Large-pore channels permeate both small anions like chloride and large signaling molecules like ATP, but how this broad cargo selectivity is structurally controlled remains elusive. Here we investigate PANX1, a prototypical large-pore channel, and uncover structural plasticity at the extracellular entrance formed by seven tryptophan (W74) residues. The W74 sidechains are flexible, sampling conformations that range from a constricted state permissive only to chloride to a dilated state compatible with ATP. These states are coupled to variable cation-π interactions between W74 and arginine 75 (R75), suggesting a mechanism for …

Book Of Abstracts, Seton Hall University

2025 Augustine Undergraduate Research Symposium

No abstract provided.

Buffer Vs. Swabs: Efficacy Of Carrier Nucleic Acids In Robotic Extractions, Shawn Cecil

Honors Projects

This study compared the efficiency of two carrier nucleic acid methods, specifically using salmon sperm DNA (spDNA), in robotic solid-phase extractions of cotton swab samples. Robotic extractions reduce processing time and workload but result in substantially lower DNA recovery than manual organic extraction. This research tested 10 µg of spDNA being added to the lysis buffer or pre-treating the swabs with it before DNA was added. Both methods showed a significant increase in recovery compared to extractions with no carrier. In the buffer extractions, recovery ranged from 69.4% to 117.5% and the swabs being pre-treated ranged from 84.2% to 125.8% …

Investigating Factors That Affect Total Ige Antibody Levels Of A Canine Population In Louisville, Ky, Iris N. Gillespie

Undergraduate Theses

Canine atopic dermatitis (CAD) is a genetically predisposed condition that causes inflammatory and pruritic (itchy) skin reactions in response to environmental and food allergens. The main purpose of this study is to determine if there is a correlation between pollen counts and total canine IgE antibody levels of dogs living in Louisville, KY. Additionally, data is analyzed to look for trends documented in previous studies related to the impacts of sex, age, and allergic symptoms on total IgE count. In collaboration with the Downtown Animal Hospital, blood samples were drawn from 16 dogs at one point in February (when pollen …

Grapes Cure Cancer: My First Molecular Docking Analysis Of Resveratrol Binding To Anti-Apoptotic Protein Bcl-2: In Silico, Sydni Ann Kolokoltsev, Vishwas Joshi

Publications and Research

B-cell lymphoma 2 (BCL-2) is an anti-apoptotic protein frequently overexpressed in cancer, enabling tumor cells to evade programmed death. Resveratrol, a grape-derived polyphenol, has reported anticancer properties. Here we performed in silico docking of resveratrol to human BCL-2 using AutoDock Vina. The best-ranked pose exhibited a predicted binding free energy of 8.0 kcal/mol and formed at least one short hydrogen bond (~1.8 Å) with pocket residues. These results support further evaluation of resveratrol as a potential modulator of BCL-2-mediated apoptosis.

The Triangular Interaction Between Dietary Polyphenols, Gut Microbiota, And Metabolic Syndrome, Emily Bayliss

Senior Honors Theses

Type 2 diabetes mellitus (T2DM) is a growing global health concern characterized by peripheral insulin resistance as well as impaired insulin secretion from pancreatic β-cells. Emerging evidence suggests that the gut microbiome, specifically gut dysbiosis, an imbalance in the gut microbiome, is a critical modulator of the pathophysiology of T2DM. Dietary polyphenols, a diverse group of bioactive compounds that are abundant in plant-based foods, have recently gained attention for their potential to attenuate metabolic disorders through their antioxidant and anti-inflammatory properties as well as through modulating the composition and activity of gut microbes, thereby attenuating dysbiosis. However, the diabetic state …

Flux Crystal Growth Of A Series Of Calcium Rare Earth Silicate Chlorides Calnsio4Cl (Ln = Pr, Nd, Sm, Eu, Gd, And Tb): Mixed Anion Materials With A Spodiosite-Type Structure, Maria Goncalves, Mark D. Smith, Hans Conrad Zur Loye

Faculty Publications

A series of calcium rare earth silicate chlorides, CaLnSiO4Cl (Ln = Pr, Nd, Sm, Eu, Gd, and Tb), was obtained as single crystals from flux crystal growth. The structures were determined by single crystal X-ray diffraction and were found to be related to the spodiosite/Wagnerite mineral structure, Ca2PO4F. The obtained compositions are variations of the spodiosite structure that result from two simultaneous elemental substitutions. Replacing one calcium for one rare earth element and the simultaneous replacement of one VO4³⁻ or PO4³⁻ with one SiO4⁴⁻. CaEuSiO4Cl was found to luminesce, and its photoluminescence spectrum is reported.

Water Circulation Beneath A Hovering Suas For Water Quality Monitoring Applications, Erin E. Hackett, Boone Fleenor, Jensine C. Coggin, Duvall Dickerson-Evans, Nikolaos Vitzilaios, Whitney E. Schuler, Paige K. Williams, Michael L. Myrick

Faculty Publications

Water quality has traditionally been measured via in situ sensors and satellites. The latter has limited applicability for smaller inland water bodies, while the former requires significant logistics, labor, and expense for routine sampling, and reactive/spurious sampling is often not feasible as a result (e.g., sampling pre-/post-storm). Consequently, small uncrewed aircraft system-based (sUAS-based) sampling has emerged as a potential solution to bridge these sampling gaps and challenges. But sampling from an sUAS is complicated by the need to pump water from depth, rather than suspending a sensor from the sUAS, due to concern over sampling sUAS-impacted waters. Here, we measure …

Thermodynamic Assessment Of The Li, Na, K, Cs | F, I Reciprocal Salt For Msr Applications, Clara M. Dixon, Mina Aziziha, Amir Mofrad, Jorge Paz Soldan Palma, Ronald E. Booth, Aiswarya Padinhare Manissery, Jack A. Wilson, Hans Conrad Zur Loye, Hunter B. Tisdale, Juliano Schorne-Pinto, Theodore M. Besmann

Faculty Publications

Gibbs energy models necessary to describe the thermochemical behavior of cesium and iodine in molten FLiNaK (46.5LiF-11.5NaF-42KF mol%), a proposed molten salt reactor coolant and fuel solvent, have been developed as they are of concern due to their high radiotoxicity and volatility. The six constituent pseudo-binary systems LiI-CsI, LiI-KI, LiI-NaI, NaI-KI, KI-CsI and NaI-CsI were evaluated using available phase equilibria and mixing enthalpy measurements. The models for the ternary reciprocal salt systems Li,Cs|F,I, Li,K|F,I, Li,Na|F,I, Na,K|F,I, Na,Cs|F,I and K,Cs|F,I were obtained by interpolation of the optimized pseudo-binary systems and parameters fit as necessary based on observed behavior. The additive (common …