Biochemistry Commons^™

Non-Destructive Imaging Of Phytosulfokine Trafficking In Plants Using Fiber-Optic Fluorescence Microscopy, Bernard Abakah

Electronic Theses and Dissertations

Plants secrete peptide ligands and use receptor signaling to respond to stress and control development. Understanding these phenomena is key to improving plant health and productivity for food, fiber, and energy applications. Phytosulfokine (PSK), a sulfated peptide hormone, regulates plant cell division, growth, and stress tolerance via specific phytosulfokine receptors (PSKRs). This study uses fiber-optic fluorescence microscopy to elucidate trafficking of PSK in live plants. The microscope features two-color optics and an objective lens connected to a 1-m coherent imaging fiber mounted on either a conventional upright microscope body or 5-axis positioning system (X–Y–Z plus pitch and yaw). PSK and …

New Dna Repair And Demethylation Functions In Uracil Dna Glycosylase Superfamily, Chenyan Chang

All Dissertations

Uracil-DNA glycosylase (UDG) superfamily, which consists of several groups of enzymes that recognize the damaged DNA bases and initiate the base excision repair (BER) pathway, is most important in dealing with DNA deamination and other base modifications. Thymine DNA glycosylase (TDG), which belongs to family 2 in the UDG superfamily, is able to specifically recognize and cleave the 5-methylcytosine (mC) oxidative derivatives including 5-formylcytosine (fC), 5-carboxylcytosine (caC), 5-hydromethyluracil (hmU) caused by active demethylation or DNA damage. My dissertation work is mainly focused on the fC and caC glycosylase activity within UDG superfamily. Chapter 1 is a general introduction to the …

Acetate Metabolism In The Fungal Pathogen Cryptococcus Neoformans, Oly Ahmed

All Dissertations

Cryptococcus neoformans is an environmental basidiomycetous fungus with a worldwide distribution and a wide range of habitats. Inhalation of the desiccated yeasts or spores of C. neoformans often leads to opportunistic pulmonary infections in immunocompromised individuals, and in severe cases causes lethal meningitis following hematogenous dissemination. During infection, depending on the tissue and disease state, the invading fungi experience a range of nutrient microenvironments within the host body. As a result, rapid metabolic adaptations geared towards efficient utilization of carbon sources alternative to glucose become one of the prime determinants of survival and growth for the pathogen. Incidentally, cryptococcal infection …

Poop! There It Is! Anti-Germinants And Biological Variables As Modulators Of Clostridioides Difficile Infection (Cdi), Jacqueline Renee Phan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Clostridioides difficile infection (CDI) is a major cause of antibiotic-associated diarrhea. Due to its insidious nature, the Centers for Disease Control and Prevention (CDC) has declared CDI an urgent threat. A key characteristic of C. difficile is its ability to form dormant spores that act as the infectious vehicles for disease. In the gut, spores recognize bile salts to germinate into toxin-producing cells.Dysbiosis of the gut microbiome is a key factor in allowing the C. difficile spores to germinate. Normal gut microbiota naturally protects from CDI. However, biological variables such as diet and sex have been found to modulate to …

Biochemical Characterization Of Fsa1572 From Fervidibacter Sacchari, The First Hyperthermophilic Gh50 With Β-1, 4-Glucanase Activity, Jonathan Covington

UNLV Theses, Dissertations, Professional Papers, and Capstones

The bacterium Fervidibacter sacchari is an aerobic hyperthermophile that catabolizes various polysaccharides and is the only cultivated member of the class Fervidibacteria within the phylum Armatimonadota. Among its glycoside hydrolase (GH) cache is an enzyme from GH family 50 (GH50), an understudied family with only 25 characterized representatives and two known activities from 1,518 predicted members in the Carbohydrate-Active EnZyme (CAZy) Database. Here, we expressed, purified, and functionally characterized an extracellular GH50 from F. sacchari called Fsa1572. Using colorimetric assays, we show it has novel β-1,4-glucanase activity and only weak agarose activity that is typical for GH50 enzymes. The purified …

Effects Of Cations And Dipicolinic Acid On B. Anthracis Spore Physiology And Cytotoxicity, Chandler P. Hassan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Inhalation of Bacillus anthracis spores leads to the most severe form of anthrax. Following phagocytosis by alveolar macrophages, spores germinate inside the phagolysosome. The mechanism used by the newly germinated B. anthracis cells to survive within macrophages is not completely understood.B. anthracis spores contain large concentrations of calcium in complex with dipicolinic acid (Ca-DPA). Upon germination, the cell excretes the large depot of Ca-DPA. DPA is an amphipathic molecule that could act as a buffer and modulate phagolysosome acidification. Intracellular calcium overload can disrupt signaling pathways required for normal macrophage function and trigger cell death. We hypothesized the release of …

Nanosecond Pulsed Electric Field Modulates Electron Transport And Mitochondrial Structure And Function, Lucas Nelson Potter

Biomedical Engineering Theses & Dissertations

Pulsed power treatment has been used to induce regulated cell death (RCD) in cells or ablate tumors in animals. A subset of pulsed power as electroporation with high voltage and pulse duration of milliseconds is used for biomedical treatment to induce pores in the plasma membrane of cells. Nanosecond Pulsed Electric Fields (nsPEFs)– an extension of electroporation, uses waveforms with pulse durations on the order of 10-900 nanoseconds. nsPEF treatment has demonstrated intracellular effects for potential biomedical applications. In this work, nsPEF treatment is used to demonstrate changes that affect viability, plasma membrane permeability ROS (Reactive Oxygen Species) in the …

Electrochemical Reduction Of Carbon Dioxide Using Ruthenium And Amines, Sydney Moise

Honors Theses

With an increased concern for climate change in the recent years, a significant area of research has been devoted to the reduction of greenhouse gases. Carbon dioxide (CO2) resides in the atmosphere between 300 – 1000 years, making the reduction of the molecule a substantial field of study.1 Amines have been used as CO2 scrubbing agents in literature historically, due to their ability to form bonds to carbon.2 Although studies involving metal catalysts and amines have been reported numerous times, research involving chemical reduction of CO2 using purely amines is scarce. In this paper, amines, in addition to hydride donors …

Potential Use Of The Gel Extract Of Butterfly Pea Flower As Topical Therapy To Prevent Photodamage By Downregulating Tnf-Α And Caspase-3 Expression Levels In Uvb-Exposed Rats, Elvana Cahyani, Agung Putra, Prasetyowati Subchan

Makara Journal of Health Research

Background: Prolonged exposure to UVB radiation causes DNA damage in skin cells by raising the levels of reactive oxygen species, resulting in the production of inflammatory factors and skin issues. Plant extracts are frequently used to counteract photodamage due to their antioxidant properties. One example is the floral extract of the butterfly pea plant, which contains flavonoid antioxidants. However, the effect of the extract on inflammatory factors is unknown. This study investigated how tumor necrosis factor-alpha (TNF-α) and caspase-3 expression changed when a butterfly pea flower extract gel was applied topically to UVB-exposed animals.

Methods: Experimental and control …

Investigating The Helicase Activity Of Methylated Vs Unmethylated Ded1, Hannah Lukow

Honors Theses

Ded1 is an RNA helicase protein of the DEAD-box subfamily in eukaryotic organisms (Sharma & Jankowsky, 2014) which can act as an activator or initiation factor, during translation (Hilliker et al., 2011). Ded1 has several functions in yeast including assembly of translational initiation factors, scanning the mRNA for the start codon, and unwinding any double stranded segments of mRNA with its helicase ability. Ded1 was discovered to be methylated at four arginine sites in vivo (Low et al., 2013), with a fifth methylation site being discovered recently (Low et al., 2020), however the purpose of such post-translational modifications is still …

The Role Of Sars-Cov-2 Orf8 Protein Arks Motif On Novobiocin Binding, Si Chun Chiu, My T. Nguyen

Celebrating Scholarship and Creativity Day (2018-)

The discovery of the SARS-CoV-2 virus during the COVID-19 pandemic required scientists to develop medical solutions to reduce infectivity, severity of symptoms, and death. Although vaccines and drugs provided urgent assistance, the need to continue developing better drugs is necessary long term, and understanding the structure of the virus and finding potential inhibitors would prove vital to discovering solutions to this worldwide health problem. This experimental project focuses on targeting the unique accessory protein, Open Reading Frame 8 (ORF8) in SARS-CoV-2 through studying its interactions with a repurposable drug, novobiocin. Importantly, ORF8 specializes in helping evade immune system checks by …

Genome Announcement For E Cluster Phage Tarkin, Katherine Cleary

Chemistry & Biochemistry Student Scholarship

Katherine Cleary ’23
Major: Biochemistry
Faculty Mentor: Dr. Kathleen Cornely, Chemistry and Biochemistry

The Role Of Cerium(Iii) In Bacterial Growth And The Microbial Transformation Of Aromatic Hydrocarbons, Shruti Sathish

Honors Theses

Biofilms are communities of surface-attached bacterial cells encased in an exopolymeric matrix. In this state, they are more resistant to antimicrobial treatment and can have adverse effects in medical, agricultural, and industrial settings. Whereas, as biocatalysts, biofilms from nonpathogenic bacteria enhance their performance and stability in catalysis. Unfortunately, there are several challenges when using bacteria in organic transformations due to their complex cellular chemistry. Trivalent lanthanide metals were discovered to serve regulatory roles in some bacterial catalytic processes, including those of Pseudomonas putida KT2440 (P. putida), a non-infectious Gram-negative bacterium. The main goal of our research is to use cerium(III) …

Toward The Design, Synthesis, And Characterization Of Abiotic Coiled-Coil Peptides Via Solid-Phase Copper-Catalyzed Azide-Alkyne Cycloaddition (Sp-Cuaac) Click Reaction For The Preparation Of Controlled Self-Assembly Molecular Building Block, Liaquat Ali

Chemistry Theses

The production of cutting-edge materials, the development of novel medications, drug delivery systems, technological advancements, and biosynthesizing all depend on molecular building blocks. Proteins are required for the creation of intricate, well-organized structures, and coiled-coil protein domains are vital subunits for the oligomerization of protein complexes, gene expression, and the structural components of biological materials. The numerous interactions between a wide variety of amino acids make it difficult to assemble protein complexes with a particular shape. In the current study, we successfully designed and synthesized four different 32-residue peptides, each of which had two modified amino azide residues. These peptides …

Apoptosis Induction In Jurkat T-Lymphocytes By Proton Pump Inhibitors (Ppis), Shreya Murali, Randall Reif

Departmental Honors & Graduate Capstone Projects

Apoptosis, commonly known as programmed cell death, constantly occurs in humans. As a cancer cell increases in acidity, apoptosis is induced. In healthy cells, proton pump proteins allow for H⁺ ions to permeate cellular membranes, regulating pH. However, proton pump inhibitors (PPIs), such as omeprazole, prevent proton movement. In previous studies, omeprazole induced cell death in Jurkat T lymphocytes; however, there was no confirmation of whether the cells died through apoptosis, or through necrosis, where the cell bursts. By using Annexin-V staining, the effects of omeprazole, dexlansoprazole, and esomeprazole on apoptosis induction can be measured. Cell death was observed …

From Deep Mutational Mapping Of Allosteric Protein Landscapes To Deep Learning Of Allostery And Hidden Allosteric Sites: Zooming In On “Allosteric Intersection” Of Biochemical And Big Data Approaches, Gennady M. Verkhivker, Mohammed Alshahrani, Grace Gupta, Sian Xiao, Peng Tao

Mathematics, Physics, and Computer Science Faculty Articles and Research

The recent advances in artificial intelligence (AI) and machine learning have driven the design of new expert systems and automated workflows that are able to model complex chemical and biological phenomena. In recent years, machine learning approaches have been developed and actively deployed to facilitate computational and experimental studies of protein dynamics and allosteric mechanisms. In this review, we discuss in detail new developments along two major directions of allosteric research through the lens of data-intensive biochemical approaches and AI-based computational methods. Despite considerable progress in applications of AI methods for protein structure and dynamics studies, the intersection between allosteric …

Assessment Of Histone Acetyltransferase Homologs In Cryptococcus Neoformans, Phoebe Bridy, Felice Kho, Yuqi Wang

Liberty University Research Week

Undergraduate

Basic

Study Of Protein Extraction Techniques For M. Foliorum Phages, Lola Sibaud, Anna Elgersma

Student Academic Conference

Characterizing phages is becoming increasingly important in biochemistry and biotechnology due to their potential to treat bacterial infections without need for antibiotics. Last year, students attempted to isolate proteins from Microbacterium foliorum infecting phages Babydotz and Rosadiaz. Proteins were successfully extracted; however, after further analysis it was shown that the obtained proteins belonged to the host bacteria and not the phages. The purpose of this study was to find a method to separate phage from host bacterial debris to successfully isolate phage proteins and analyze them later. Isolating phage proteins could help us characterize more phages and know more about …

Novel Plant Peroxidase Investigation For Use In Various Biochemical And Practical Applications, Sally Hess

Liberty University Research Week

Undergraduate

Basic

Activation Of Nrf2 Pathway By Natural Products, Genesis Schat, Madelyn Sedlachek

Liberty University Research Week

Undergraduate

Basic