Biochemistry Commons^™

Comparative Animal Mucomics, Antonio R. Cerullo

Dissertations, Theses, and Capstone Projects

Mucus is one of Nature’s most abundant and versatile biomaterials. These secretions are present in all animals, from the lowly garden snail to the great blue whale, and fulfill a multitude of functions, acting as antimicrobial barriers, moisturizers, adhesive glues, surface lubricants, and mineralizing agents. Despite their importance, very little is known about mucus compositions or properties. The largest challenge precluding the greater understanding of mucus function is its complexity; a single mucus contains complex mixtures of proteins, glycans, and ions that all have important roles in function. Therefore, understanding mucus function necessitates analysis that compares different mucus from one …

Assessing Lipid Composition Of Cell Membrane In Escherichia Coli Under Aerobic And Anaerobic Conditions, Isabelle Johnson

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Escherichia coli is a highly studied model organism that is tightly tied to the mammalian gastrointestinal system. This microorganism has the capability to be a beneficial gut microbe or a life-threatening pathogen. In this study, the lipid membrane of Escherichia coli was investigated using Matrix-Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) to observe the change in its composition in aerobic and anaerobic conditions. Evidence of desaturation was discovered in the spectra, though more investigation is needed to understand the metabolic processes and drives that result in this change. Elucidation of these pathways in the future could result in …

Institutional And Individual Approaches To Change In Undergraduate Stem Education: Two Framework Analyses, Stephanie B. Feola

USF Tampa Graduate Theses and Dissertations

The overarching goal of this dissertation is to examine institutional change initiatives in STEM and to understand the impact of engaging with a specific change strategy on a biochemistry educator’s instructional practice. Institutional change initiatives involve executing an intentional strategy to influence teaching practices within a specific institution. This research investigates NSF-funded change initiatives at three public research universities that were focused on encouraging the adoption of evidenced-based instructional practices (EBIPs) by STEM faculty. As part of an effort to understand how the three institutions approached this task, framework analysis was performed using the initiative’s annual reports to NSF. Further …

Characterizing The Roles Of The Variable Linker And Hub Domains In Camkii Activation, Noelle Dziedzic

Doctoral Dissertations

Learning and memory formation at the cellular level involves decoding complex electrochemical signals between nerve cells, or neurons. Understanding these processes at the molecular level requires a comprehensive study of calcium-sensitive proteins that serve as signal mediators within cells. More specifically, the protein calcium/calmodulin-dependent protein kinase II (CaMKII) is a key regulator of downstream cellular signaling events in the brain, playing an important role in long term memory formation. CaMKII is encoded in humans on four different genes: alpha, beta, gamma and delta. For added complexity, each of these gene products can be alternatively spliced and translated into multiple protein …

Extension Of The Ergot Alkaloid Gene Cluster, Samantha Joy Fabian

Graduate Theses, Dissertations, and Problem Reports

Specialized metabolites produced by fungi impact human health. A large portion of the pharmaceuticals currently on the market are derived from metabolites biosynthesized by microbes. Ergot alkaloids are a class of fungal metabolites that are important in the interactions of environmental fungi with insects and mammals and also are used in the production of pharmaceuticals. In animals, ergot alkaloids can act as partial agonists or antagonists at receptors for 5-hydroxytryptamine (serotonin), dopamine, and noradrenaline as ergot alkaloids have chemical structures similar to those neurotransmitters. Therefore, they affect insects and mammals that consume them and can be used to produce drugs …

Development Of Multivalent Dna-Peptide Nucleosome Mimetics And Multi-Domain Protein Inhibitors That Directly Or Indirectly Target The E3 Ligase Uhrf1, Li Gu

University of the Pacific Theses and Dissertations

UHRF1 is an E3 ubiquitin ligase and a key epigenetic regulator establishing a crosstalk between DNA methylation and histone modification. Despite the important biochemical role of UHRF1 in cells, its overexpression has been found in almost all primary cancer types including breast cancer, lung cancer and so on. Numerous evidence indicates a strong link between tumorigenesis and UHRF1 overexpression, supporting its potential as a universal biomarker for cancer. However, UHRF1 is “yet-to-be drugged” and no highly potent chemical probes have been developed to target UHRF1 to date. In this study, we proposed two drug design approaches for UHRF1. The first …

Development Of Nucleic Acid Diagnostics For Targeted And Non-Targeted Biosensing, Christopher William Smith

Legacy Theses & Dissertations (2009 - 2024)

The field of nucleic acid technology is rapidly expanding with new impactful discoveriesbeing made each year. Starting from the discovery of the double-helix structure, cloning, gene editing, polymerase chain reaction (PCR), CRISPR technology, and even the late mRNA vaccines; nucleic acid technology is at the forefront of improving medicine. Nucleic acid technology is extremely versatile due to its easy programmability, automated cheap synthesis, and even its catalog for numerous chemical modifications that can be used to alter structure stability. For example, the number of permutations that can be made with DNA just by altering the code for adenine (A), cytosine …

Targeting Heat Shock 27 Kda Protein Induces Androgen Receptor Degradation, Yaxin Li

ETD Archive

Glioblastoma (GBM) is the most common and aggressive brain tumor, with very poor prognosis. Androgen receptor (AR) plays a significant role in the progression of GBM, and anti-androgen agents have the potential to be used for the treatment of GBM. However, AR mutation commonly happens in GBM, which makes the anti-androgen agents less effective. Heat shock 27 kDa protein (HSP27) is a well-documented chaperone protein to stabilize AR. Inhibition of HSP27 results in AR degradation regardless the mutation status of AR, which makes HSP27 a good target to abolish AR in GBM. Identified compound I ((N-(3-((2,5-dimethoxybenzyl)oxy)-4-(methylsulfonamido) phenyl)-4-methoxybenzamide) inhibits GBM cell …

Assembly Of The Peripheral Arm Subunits Of Escherichia Coli Complex I And Analysis Of Clinical Mutations, Hind Alkhaldi

Biological Sciences Theses and Dissertations

Respiratory Complex I from E. coli is a proto-type of the mitochondrial enzyme, consisting of a 6-subunit peripheral arm (B-CD-E-F-G-I) and a 7-subunit membrane arm. When subunits E-F-G (N-module), were expressed alone they formed an active complex as determined by co-immunoprecipitation and native gel electrophoresis. When co-expressed with subunits B and CD, only a complex of E-F-G was found. When these five subunits were co-expressed with subunit I and two membrane subunits, A and H, a complex of B-CD-E-F-G-I was membrane-bound, constituting the N- and Q-modules. Assembly of Complex I was also followed by splitting the genes between two plasmids, …

Computational Investigation Of Calmodulin Photocontrol With The Help Of An Azobenzene Derivative, Jeremy Wells

Undergraduate Honors Theses

The ability to control the activity and binding capability of enzymes in a reversible manner offers tremendous control over biological processes. Photocontrol, in particular, is promising in that electromagnetic radiation can be fine-tuned in terms of its strength, location, and duration. Photosensitive compounds, such as the azobenzene family, experience an isomerization at certain wavelengths, and attaching these compounds to enzymes has the potential to alter their structure and activity. Calmodulin (CaM) is a Ca2+ -sensitive signaling protein that has the ability to affect several downstream processes in eukaryotes and is an excellent target for photocontrol due to its small size …

Mechanisms Of Telomere Maintenance In Trypanosoma Brucei, M A G G. Rabbani

ETD Archive

Telomeres are a nucleoprotein structure at the end of the chromosome and are essential for genome integrity and chromosome stability. Telomere lengths are primarily maintained by a telomerase-mediated pathway but can be maintained by a homologous recombination-mediated pathway. However, detailed mechanisms of telomere maintenance are still unclear in many eukaryotes, including an important human pathogen, Trypanosoma brucei. Telomeres can be elongated by telomerase in T. brucei, a causative agent of fatal sleeping sickness in humans and nagana in cattle. T. brucei evades host immune response by regularly switching its major surface antigen, variant surface glycoprotein (VSG), a process known as …

Covalent Modification Of Recombinant Protein With Reactive Thiols, Sawyer Dulaney, Bailey Taylor

Honors Theses

Many diseases cause chronic and painful inflammation in different body systems. One of the front-line drug classes to treat such inflammation is Nonsteroidal Anti-Inflammatory Drugs (NSAIDs). Despite the benefits of oral administration of NSAIDs, there are drawbacks to their long-term usage because they can cause detrimental effects on off-target systems in the body such as the liver, kidney, or the lining of the intestinal tract. An alternative to NSAIDs is the usage of hydrogels for targeted drug delivery. Hydrogels can provide drug delivery in a specific portion of the site of inflammation, thus allowing higher doses of medication to be …

Development Of New Treatments For Asthma And Neuropathic Pain Based On Ɣ-Aminobutyric Acid A Receptor (Gabaar) Ligands, Nicolas Mark Zahn

Theses and Dissertations

The γ-aminobutyric acid A receptor (GABAAR) is a ligand-gated pentameric chloride channel consisting of several identified subunits: α1-6, β1-3, γ1-3, δ, ε, π, θ, ρ1-3.1-2 Typical arrangement of subunits consists of two α subunits, two β subunits, and one γ subunit.3 GABAARs have two binding sites for the endogenous ligand γ-aminobutyric acid (GABA), between the α and β subunits. GABAARs also have a binding site for positive allosteric modulators, such as benzodiazepines, between the α and γ subunits.4-5 Due to their ability to treat anxiety, epilepsy, insomnia, and muscle relaxation, benzodiazepines are widely prescribed pharmaceuticals.6-7 Still, adverse effects result from …

Genetic Analysis Of Adhesion Protein Elmo3 In Arabidopsis Thaliana, Garrison Asper

Honors Projects

The Extracellular Matrix (ECM) between plant cells is vital for structure, development, and intercellular adhesion. A pectin rich layer in between cells, the middle lamella, is largely responsible for regulating the adhesive properties of adjacent plant cells. Homogalacturonan (HG) pectin, the most common, is synthesized in the Golgi and secreted into the ECM where it undergoes calcium crosslinking, increasing its adhesive properties. Mutations in proteins essential for HG synthesis can reveal a severe adhesion defective phenotype, where the hypocotyls of dark grown Arabidopsis exhibit cell sloughing, curling, and general disorganization. A family of five ELMO proteins are suspected to act …

Investigating Spatiotemporal Kinetics, Dynamics, And Mechanism Of Exosome Release, Anarkali Mahmood

Electronic Theses and Dissertations

Exosomes are small lipid-based vesicles that can carry biomolecules from one cell to another. While exosomes are crucial to maintain homeostasis in healthy cells, they are exploited by unhealthy cells to aid disease progression. Exosomes likely facilitate disease progression via the transfer of disease-causing biomolecules from unhealthy to healthy cells. Exosomes are generated in Multivesicular endosomes (MVEs) and are then secreted into the extracellular space to travel to other cells. Despite being a crucial step, very little is known about exosomes release mechanism and dynamics. To further our understanding of exosomes, specifically their secretion, my work has focused on investigating …

The Role Of Rad51 In Trichomonas Vaginalis, Dominique Hall

University of the Pacific Theses and Dissertations

Drug resistance to the current treatments on the market is on the rise, therefore there is strong interest in understanding what could be causing the resistance, how resistance could be spreading through the population, and finding some possible new drug targets. One protein of interest is Radiation Sensitive Protein 51 (Rad51). It is a protein that is involved in homologous recombination as well as other processes such as DNA damage repair. While Trichomonas vaginalis traditionally has been known to replicate via binary fission, a modified form of closed mitosis, there is some evidence that meiosis, or at least some form …

Investigation Of A Carbon Monoxide Dehydrogenase From An Uncultured Archaeon, Luke Moore

Dissertations, Master's Theses and Master's Reports

The Nickel based Carbon Monoxide Dehydrogenase (CODH) is an anaerobic metalloenzyme responsible for the reversible conversion of CO and water into CO2 and 2 protons and 2 electrons. This enzyme has importance in the environment as one of Earth’s first carbon fixation pathways, and for human uses as a potential source of biofuels and other commodity chemicals. CODH enzymes are present in a wide array of taxa, many of which are uncultured. In this study we express and purify the catalytic subunit (CooS) of the anaerobic CODH from an uncultured Hydrothermarchaeota JdFR-17 co-expressed with the nickel insertion accessory protein (CooC) …

Molecular Mechanisms Of Aberrant Protein Glycosylation In Pancreatic Cancer Stemness And Metastasis, Frank Leon

Theses & Dissertations

A myriad of genetic and other abnormal changes underlies the aggressiveness and dissemination properties observed in pancreatic cancer (PC). Aberrant protein glycosylation is a commonly observed feature in PC. The modification of protein O-glycosylation is mediated by glycosyltransferases, which attach and sequentially elongate monosaccharides on Serine/Threonine (Ser/Thr) motifs. Aberrant glycosylation is recognized as an emerging hallmark of cancer where a disruption in normal glycosylation results in irregular O-glycans.

This dissertation research has investigated the consequences of aberrant protein glycosylation on stemness and enhancement of metastatic properties in pancreatic ductal adenocarcinoma (PDAC). Several publications have reported aberrant O-glycosylation increases in oncogenic …

Mechanistic Insights Into Diverse Protease Adaptor Functions, Nathan J. Kuhlmann

Doctoral Dissertations

Protein degradation is an essential cellular process that helps maintain proper homeostasis. The ClpXP protease broadly regulates bacterial development and quality control during the cell cycle. The range and order of substrates that ClpXP degrades during the cell cycle is dictated by 3 accessory proteins, which are known as adaptors. This thesis will elaborate on how dimerization tightly regulates the stability and activity of the adaptor protein at the center of this hierarchy, RcdA, and show how this affects normal cellular processes in Caulobacter crescentus. I will discuss the mechanism by which dimerization limits RcdA activity and how the dimerization …

Mucinomics: A Bioinformatic Analysis Of Snail Mucins, And Their Function, Maxwell B. Mcdermott

Theses and Dissertations

This thesis outlines the current research on secreted snail mucus, highlighting the potential of this biopolymer, and also demonstrates a research strategy to fulfill the unmet need of examining the hierarchical structures that lead to the enormous biological and chemical diversity of snail mucus genes.

Determination Of The Structure, Function, And Mechanism Of Type Iv Crispr-Cas Prokaryotic Defense Systems, Hannah Nicole Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bacteria are under constant threat of invasion by bacteriophage (viruses which infect bacteria). To prevent bacteriophage from entering and overtaking the bacteria, bacteria utilize defense systems to identify and destroy foreign elements. One method of defense is called CRISPR-Cas (Clustered Regularly Interspaced Short Palindromic Repeats – CRISPR-Associated). Many different bacteria and most archaea use CRISPR-Cas systems. There are many diverse types of CRISPR-Cas systems, each of which provides defense in a slightly different way. One such CRISPR-Cas type is called type IV. The type IV CRISPR-Cas system is poorly understood and there are very few studies published on type IV …

Ahr Expression On Rorc-Expressing Immune Cells Is Essential For I3c-Mediated Protection Against Colitis, Michal C. Williams

Senior Theses

Colitis is an inflammatory bowel disorder (IBD) whose etiology is attributed to modification in the luminal microbiota and dysregulation in the immune response. Indole is a signaling molecule which is naturally produced by gut luminal microbiota. Indole-3- carbinol (I3C) is a compound commonly found in vegetables and a ligand for the aryl hydrocarbon receptor (AhR). Previous studies have detected decreased expression and activation on the AhR receptor in colitis patients, thought to possibly alter gut microbiota metabolism, subsequently promoting colitis. 1 AhR, expressed in a variety of immune and epithelial cells, contributes to gut homeostasis by affecting vital mediators such …

Investigating The Mechanism Of The Escherichia Coli Atp-Binding Cassette (Abc) Transporter Metni, Matthew Foronda

Master's Theses

Chemical homeostasis is a baseline requirement for any cell to survive. ATP-binding cassette (ABC) transporters play a vital role in homeostasis by importing nutrients and exporting toxins against their concentration gradients by utilizing the energy of ATP hydrolysis. Malfunctioning ABC transporters cause a variety of health problems, including cystic fibrosis, Stargardt’s disease (vision loss), and the development of drug-resistant tumors. An important step in solving these medical issues is to first understand the structure and mechanism of ABC transporters. Various studies have made great strides in depicting the structure and details of different ABC transporters and their mechanisms, however, many …

Chemical And Co-Solute Effects Of Polyethylene Glycol On I-Motif Formation, Lindsey Rutherford

Honors Theses

DNA typically forms Watson and Crick double helix structures in which adenine, thymine, guanine, and cytosine pair with their complimentary DNA base. However, DNA i-motif structures can form in cytosine rich DNA, typically under slightly acidic conditions (~pH 6). DNA i-motifs are four stranded secondary structures in which cytosine pairs with cytosine to form a quadruplex. The i-motifs are typically formed in acidic conditions because of the protonation in the C•C base pair between one of the three hydrogen bases. Recent studies have suggested i-motifs can also form under neutral conditions, which is more realistic for a cell. It is …

Effects Of Crowding Agents On I-Motif Dna, Hayden Brines

Honors Theses

Deoxyribonucleic acid (DNA) is a well-known double stranded, helical, biological molecule. In addition to its more commonly known structure, DNA can also form more complicated structures like G-quadruplexes and i-motifs (iM). The iMs are formed by cytosine rich DNA and are a four stranded structure that is typically looped around itself. The iM formation is typically pH-dependent and is favored in more acidic conditions; the pKa value is approximately 6.5. This pKa value allows for potential in vivo formation, since the cells have a pH of approximately 7.3. Due to this, iMs are thought to be powerful, innovative molecules for …

Pectin And Alginate Extraction To Treat Liquid Cafo Manure, Clare Sunderman

Honors Projects

For this project, various extraction methods were used to extract pectin from Pastinaca Sativa and alginate from Macrocystis. These extractions were then dried and used in treating 250mL of manure along with a CaCl₂ or FeCl₃ coagulant. It was found that CaCl₂ was not as effective as FeCl₃ in coagulating manure. But the results obtained suggest that pectin and alginate obtained with a simpler extraction method is just as effective as the highly purified and refined pectin and alginate produced for the food industry, in the treatment of CAFO manure. The liquid portion of the …

Lions, Tigers, And Hemes - Oh My! A Dynamic Look At The Electronic Effects Of Porphyrin Substitution On Cytochrome P450 Olet, Alexis J. Holwerda

Senior Theses

OleT, a member of the CYP152 family of cytochrome P450s (CYPs), decarboxylates fatty acids using hydrogen peroxide as an oxidant. The resultant products are a terminal alkene and carbon dioxide. This C–C cleavage reaction is highly atypical for CYPs, which prototypically oxygenate substrates, and provides a potential means to enzymatically produce drop-in fuels. OleT contains a heme-iron cofactor that facilitates decarboxylation through the activation of hydrogen peroxide. The catalytic cycle, as determined by transient kinetics, includes two ferryl intermediates known as Compound I (Ole-I) and Compound II (Ole-II). Ole-I performs substrate hydrogen abstraction and subsequent single electron transfer to Ole-II …

Purification And Functional Characterization Of The Iron-Responsive Transcription Factor Aft1 From C. Glabrata, Jade Ikahihifo-Bender

Senior Theses

Due to its unique ability to serve as both an electron donor and acceptor, iron is utilized as a co-factor for many biological processes, including electron transfer, oxygen binding, and vitamin synthesis. Iron is also a key factor during fungal infections as the human host and invading pathogens battle over limited iron pools. The primary iron-responsive transcription factor Aft1 in the opportunistic pathogenic yeast Candida glabrata responds to iron deficiency by activating expression of iron acquisition genes. However, the mechanisms for sensing intracellular iron levels and regulating Aft1 activity in response to iron are unknown. The C. glabrata iron regulation …

Development Of Linked-Domain Protein Inhibitors Of The E2-Conjugating Enzyme Ube2d, Anneroos E. Nederstigt

University of the Pacific Theses and Dissertations

In most eukaryotic organisms, the ubiquitination pathway is one of the most important and versatile signaling systems in use. It is integral to processes such as protein degradation and homeostasis, DNA repair cell cycle regulation, signaling and regulation, epigenetics, and many more. Ubiquitin (Ub) is a short polypeptide of 8.6 kDa, 76 residues that functions as a reversible post-translation modification (PTM). It furthermore contains 7 different lysine residues (K6, K11, K27, K29, K33, K48, K63), all of which can form isopeptide linkages with one another to link individual Ub moieties to form unique polyUb chains onto substrates. The type of …

Investigation Of Potentially Catalytic Residues Of Uba5 Through Mutagenesis, Purification, And Structural Characterization, Grant Bradley

Senior Honors Projects, 2020-current

Ubiquitin-fold modifier 1 (Ufm1) is a member of the Ubiquitin (Ub) family of proteins whose primary function is degradation of proteins through a sequential mechanism of chemical reactions. Though Ufm1’s specific roles are largely unknown, this family of proteins has shown to play a part in a wide variety of processes, including regulation of the cell cycle¹, secretory functions of cells^2,3, and blood clotting⁴. Ufm1’s mechanism of action proceeds with the aid of three enzymes: an E1, E2, and E3. Uba5 is the E1 activating enzyme that is specific to Ufm1, and its mechanism of …