Biochemistry, Biophysics, and Structural Biology Commons^™

A Study Of Cobalt (Iii) Oxide Nanoparticle Delivery Of Sirna Molecules Directed Against Signaling Intermediates Of The P2y2 Receptor, Rachel Blair Stroud

Graduate Theses/Dissertations

G protein-coupled receptors are evolutionarily ubiquitous sensors of extracellular signals, propagating intracellular signal cascades through heterotrimeric G proteins. P2Y₂ receptors are GPCRs which are activated by extracellular nucleotides to mediate signaling cascades via Gαq coupling. Many GPCRs are subject to a common mechanism for signal termination involving phosphorylation of the C-terminal tail followed by β-arrestin binding and subsequent endocytic internalization of the complex. This effect has been described for the P2Y₂ R in the 1321N1 astrocytoma cell line, and UTP-induced activation and desensitization profiles have been previously defined. There is need to develop molecular vehicles for safe and …

Function And Expression Of Ribonucleotide Reductase-Encoding Genes In Flavobacterium Johnsoniae, Hunter Scott Doheny

All Graduate Theses, Dissertations, and Other Capstone Projects

Ribonucleotide reductases (RNRs) are essential enzymes that are involved in DNA synthesis. While this makes them ideal targets for antiproliferative drugs, most known RNR targeting agents are nonspecific. This poses a problem when considering antimicrobials, but several groups of bacteria have RNRs that utilize unique mechanisms that could be exploited if fully understood. One such bacteria, Flavobacterium johnsoniae, has the gene for a class Id RNR with a novel activation mechanism. Class Id RNRs belong to the aerobic class I RNRs and seem to have a unique metallocofactor and activation mechanism involving superoxide and manganese. The goal of this research …

Antibacterial Activity Of Commiphora Molmol (Myrrha) Against The Yeast, Mohammad Hassan Alshehri

Selected Full-Text Master Theses 2021-

Commiphora molmol (myrrha) is widely used as a traditional medicine around the globe against inflammatory diseases. It is also considered to be effective as anti-fungal, anti-cancer and anti-oxidant agent. The minimum inhibitory concentration, bactericidal activity and heat stability of antibiotic component in myrrha oil extract has been investigated. The MIC was determined in nutrient free buffer and in nutrient rich peptone glucose buffer. The results showed that MIC was 0.6% in nutrient free buffer as no growth was shown by cells, whereas, in peptone glucose media a slight increase in cell count was seen. It can be concluded that it …

Further Investigation Of The Initiating Mechanism Of The Type I Collagen Glomerulopathy, Matthew James Freese

Graduate Theses/Dissertations

The progressive accumulation of collagen and other extracellular matrix proteins in the renal mesangium results in fibrosis, glomerulosclerosis, and eventual renal failure. Mice deficient in integrating α2(I) collagen into the type I collagen structure, termed Col1a2-deficient mice, model kidney fibrosis through the condition Type I Collagen Glomerulopathy, because homotrimeric type I collagen accumulates extracellularly in the mesangium of renal glomeruli. Accumulation of homotrimeric type I collagen compresses blood vessels in glomeruli, which reduces filtration, increases pressure, and results in fibrosis. Picrosirius red (PSR) staining was used on Col1a2 deficient and wildtype mice to evaluate collagen deposition. Histological evaluation and …

Exosomal-Long Non-Coding Rnas Journey In Colorectal Cancer: Evil And Goodness Faces Of Key Players, Nehal I. Rizk, Ahmed I. Abulsoud, Mohamed M. Kamal, Dina H. Kassem, Nadia M. Hamdy

Pharmacy

Exosomes are nano-vesicles (NVs) secreted by cells and take part in cell-cell communications. Lately, these exosomes were proved to have dual faces in cancer. Actually, they can contribute to carcinogenesis through epithelial-mesenchymal transition (EMT), angiogenesis, metastasis and tumor microenvironment (TME) of various cancers, including colorectal cancer (CRC). On the other hand, they can be potential targets for cancer treatment. CRC is one of the most frequent tumors worldwide, with incidence rates rising in the recent decades. In its early stage, CRC is asymptomatic with poor treatment outcomes. Therefore, finding a non-invasive, early diagnostic biomarker tool and/or suitable defender to combat …

Sources And Therapeutic Strategies Of Mesenchymal Stem Cells In Regenerative Medicine, Mohamed M. Kamal, Dina H. Kassem

Pharmacy

During the past decade, mesenchymal stem cells (MSCs) have made their mark as a potential weapon in regenerative medicine. Since their first isolation by Friedenstein in the late 1970s of the last century, MSCs have opened new avenues in the field of regenerative medicine. The main fascination about MSCs lies in their ease of isolation and large ex vivo expansion capacity, as well as demonstrated multipotency and immunomodulatory activities. Basically, several reports have proved that MSCs isolated from different sources possess different characteristics and potentials. In addition, the mechanisms by which these cells can help regenerate tissues and treat several …

Protumorigenic Effects Of Mixed Lineage Kinase Domain-Like Protein In Cholangiocarcinoma Cells, Nattaya Duangthim

Chulalongkorn University Theses and Dissertations (Chula ETD)

Cholangiocarcinoma (CCA), a heterogeneous malignancy of bile duct system, has the highest incidence in Thailand. CCA is one of the leading causes of death which has low 5-year survival rate from 5% to 10% in advanced stages due to the difficulty of diagnosis in early stage and lack of effective therapies. Therefore, understanding the molecular mechanisms and pathogenesis of CCA development and progression is urgently needs and will lead to the development of novel therapeutic targets and strategies. Mixed lineage kinase domain-like (MLKL) was identified as a key effector in a novel regulated necrosis or necroptosis pathway. Recently studies have …

Characterizing The Relationship Of Lgl1 And Akt In Migration Of Murine Neural Stem And Progenitor Cells, Natalie Pedicino

Cal Poly Humboldt theses and projects

Asymmetric cell division and migration are critical for neural stem cell differentiation and brain development. When these processes are dysregulated in neural progenitor cells (NPCs), developmental defects and diseases like glioma can result. Lgl1 is a tumor suppressor gene that was first characterized in Drosophila neuroblasts (Strand et al., 1994). It is best known for its regulation of asymmetric cell division through its association with the Par complex. The PI3K/AKT signaling cascade is involved in cellular migration and is also regulated by Par signaling. Unpublished data from the Sprowles laboratory suggests a potential role of Lgl1 in migration and other …

Investigating The Main Protease (Mpro) Of Sars-Cov-2 As A Potential Drug Target, Valerie Giovina Pascetta

Honors Theses and Capstones

The rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the coronavirus disease 19 (COVID-19) pandemic has claimed the lives of roughly 6.2 million people worldwide as of May 2022. The virus’s main protease (M^pro ) has been identified as an attractive drug target due to the critical role it plays in the viral life cycle. The roughly 34 kDa M^pro cleaves functional viral polypeptides out of two long polyproteins at conserved cut sites, allowing them to fulfill their role in processes like transcription and replication. Here, we have studied the enzymatic activity …

Production And Biological Activities Of Oligo Pectin From Early Immature Fruit Of Durio Zibethinus L., Aunchiya Pitaksa

Chulalongkorn University Theses and Dissertations (Chula ETD)

Early immature durian (EID) fruits, 30-45 days after anthesis with 6-12 cm in length, are considered agricultural waste from cultivation. It is known that durian rinds of mature fruits contain pectin, but there have been no reports on the pectin content of early immature durian (EID) fruits. Therefore, the objective of this study was to determine the pectin content in EID fruits. We extracted pectin from EID fruits using distilled water at different temperatures (25°C, 50°C, and 75°C) for 1 h to investigate pectin content. Instrumental analyses, including X-ray diffraction (XRD) and Fourier Transform Infrared Spectrometer (FT-IR), confirmed the presence …

Anti-Neuroinflammatory Effects Of Auricularia Polytricha Extracts On Bisphenol A (Bpa)-Induced Microglial Cell Activation And Reduction Of Hippocampal Cell Damage, Chanin Sillapachaiyaporn

Chulalongkorn University Theses and Dissertations (Chula ETD)

Bisphenol A (BPA) is widely used in the production of polycarbonate plastics, it has been reported that BPA can activate neuroinflammation. Neuroinflammation is a brain pathology that involves the high levels of pro-inflammatory mediators, including tumor necrosis factor-alpha (TNF-α). An excessive TNF-α expression could result in neuronal cell death and subsequently lead to neurodegeneration. Auricularia polytricha (AP) is an edible mushroom with several medicinal properties. Herein, the anti-neuroinflammatory effects of AP extracts against BPA-induced BV2 microglial inflammation were investigated. Hexane (APH) and ethanol (APE) extracts of AP inhibited BPA-induced neuroinflammation in BV2 cells by reducing the expression of pro-inflammatory cytokines. …

Purification And Activity Assay Optimization Of Bacterial Catalase From Psychrobacter Koprana, Sydney Willis

Honors Program Theses

To date, catalase protein from bacterial species is not the most widely used commercial catalase. Catalase, the enzyme that breaks down hydrogen peroxide in most living organisms, is an invaluable enzyme in the food, agriculture, and pharmaceutical industries. In 2019, a novel species of a psychrotolerant bacterium was discovered in Cold Harbor, NY. This species, Psychrobacter koprana, exhibits highly active catalase. Preliminary data from activity assays demonstrates that P. koprana catalase has the same activity as commercially available catalase. After purification and activity assay optimization, the activity of this catalase has the potential to be more active than other easily …

Identifying The Role Of Cholesterol And The Cholesterol Transfer Protein, Ysp1-2, In Cell-Cell Fusion In Tetrahymena Thermophila, Natasha D. Kusibab

Honors Program Theses

A cell’s shape directly affects how it behaves as one’s structure directly correlates to its function. The shape of cells and organelles is driven in part by the lipid bilayer that makes up their membranes. The process by which cells systematically adjust the types of lipids in membranes to facilitate changes in membrane shape remain uncertain. In our research, we aimed to address this issue by studying the role of lipid transfer proteins in the ciliate, Tetrahymena thermophilia. Specifically, we focus on the process of cell-cell fusion during mating in Tetrahymena as this requires a drastic change in membrane shape …

Effects Of Azadirachta Indica Extract On Inhibition Of Glutamate-Induced Neuronal Cell Apoptosis Via Preventing Excessive Mitophagy Activation And Inhibiting Endoplasmic Reticulum Stress In Ht-22 Cells, Kuljira Mongkolpobsin

Chulalongkorn University Theses and Dissertations (Chula ETD)

Neurodegenerative diseases (NDs) are the age-related diseases which represent a major cause of mortality in aging population nowadays. Previous studies have shown that glutamate, the most abundant excitatory neurotransmitter, significantly increases in extracellular fluid of the patient’s brain and is the cause of neurodegeneration in NDs. The increase of extracellular glutamate elevates reactive oxygen species (ROS) accumulation and calcium (Ca2+) which exacerbate mitochondrial function, followed by inducing MAPK pathway and endoplasmic reticulum (ER) stress, respectively. In addition, Ca2+ overload also triggers calpain, a Ca2+ dependent protease, activity which further stimulates Cdk5/p35/p25 signaling leading to neuronal apoptosis. Azadirachta indica A. Juss. …

Type-B Energetic Processes And Their Associated Scientific Implications, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

Recently, our work has identified two thermodynamically distinct types (A and B) of energetic processes naturally occurring on Earth. Type-A energy processes such as the classical heat engines, ATP hydrolysis, and many of the known chemical, electrical, and mechanical processes apparently follow well the second law of thermodynamics; Type-B energy processes, for example, the newly discovered thermotropic function that isothermally utilizes environmental heat energy to do useful work in driving ATP synthesis, follow the first law of thermodynamics (conservation of mass and energy) but do not have to be constrained by the second law, owing to its special asymmetric functions. …

Here, There, And Everywhere: Probing Ubiquitin-Cavitand Binding Via 15n-1h Hsqc, Julia Didziulis

Scripps Senior Theses

Ubiquitination and other post-translational modifications play a major role in the proliferation of many neurodegenerative diseases, developmental disorders, and cancers, and as such are subjects of recently increased biochemical interest. Expanding upon such research, this study confirmed a robust method of ubiquitin expression and purification, then used 15N-1H HSQC to analyze ubiquitin samples containing varying concentrations of a deep cavitand with affinity for lysine and arginine side chains. In the pure ubiquitin spectrum, arginine side chain chemical shifts were detected in the nitrogen 80-85 ppm range and lysine side chain signals were undetected. However, upon introduction of the cavitand, collection …

Simulation Of An Inflammatory Model Using Schwann Cells, Caitlyn E. Henry, Peyton Kimmel, Mackenzie Wilcox, Angela Asirvatham

SURF Posters 2022

Schwann cells are a type of glial cell in the peripheral nervous system that produce the myelin sheath surrounding neuronal axons. This myelin insulates the neurons and promotes the rapid conduction of electrical impulses throughout the body. Schwann cells have also been found to play a critical role in neuron repair following nerve injury. During nerve injury, the myelin sheath is damaged, stimulating Schwann cells to release cytokines, or inflammatory mediators, that recruit immune cells to the site of injury so that the myelin debris can be cleared, and repair can take place.1 Then neuronal growth is facilitated by heregulin …

An Integrative Investigation Of The Synechococcus A/B Clade During Adaptive Radiation At The Upper Thermal Limit Of Phototrophy, Christopher L. Pierpont

Graduate Student Theses, Dissertations, & Professional Papers

Thermophilic microorganisms have been scientifically observed since the early nineteenth century and have spurred many questions about the limits of life and the capacity of organisms to survive extreme conditions. Decades of research on thermophile proteins and genomes have yielded several proposed correlates of temperature that may contribute to adaptation of bacteria and archaea to high temperature. However, many of the generalizations reported are drawn from analyses of deeply divergent taxa or from individual case studies in isolation from mesophilic relatives. Members of the Synechococcus A/B (SynAB) group are the only cyanobacteria with members able to grow above 65 °C …

Genomic Instability At A Polypurine/Polypyrimidine Repeat Sequence, Nathen S. Zavada

Browse all Theses and Dissertations

Microsatellite repeat sequences have been shown to induce replication stalling, fork collapse, double-strand breaks (DSBs), and possibly stimulate break-induced replication. In this study we use a dual-fluorescent HeLa model that is designed to monitor recombination at an ectopic site through use of flow cytometry and inverse PCR with a microsatellite in the lagging strand for DNA synthesis. To test the stability of the 78 bp polypurine/pyrimidine repeat from the PDK1 locus, we subjected cells to replication stress drugs designed to induce DSBs and measure break-induced replication (BIR). The study revealed that polypurine repeat cells undergo endogenous stress contributing to instability …

Sequential Block Copolymers Of Polyisobutylene And Polyolefins, Manwel Labib

Williams Honors College, Honors Research Projects

A two-step approach will be utilized to synthesize random polyolefin multiblock-copolymers. This strategy takes advantage of a,w-terminated telechelic polyolefins. Polypropylene (iPP)/polyethylene (PE) are picked because of their strength, and polyisobutylene (PIB) because of its hemocompatibility. This copolymer is theorized to make for robust bio-inert plastic, which can be used for surgical mesh implants.

Mimicking The Namib Desert Beetle With Hydrophilic And Hydrophobic Surfaces, Tyler Bracewell

Williams Honors College, Honors Research Projects

The Namib Desert beetle, Stenocara gracilipes, condenses fog that rolls in off the west coast of Namibia to provide itself with the water it needs for the day. By lifting its abdomen into the air to collect the water vapor, it condenses on hydrophilic bumps that are about 500μm in diameter and are spaced apart about 500-1500μm. Once the water reaches a critical size, the droplet rolls off the hydrophilic bump and onto the flat hydrophobic surface of the elytra. Since the beetle is angled with its abdomen in the air, the water rolls down to its mouth. A …

Characterizing The Post-Translational Modifications Of The Pro-Oncogenic Type Ii Transmembrane Serine Protease Tmprss13, Carly Elizabeth Martin

Wayne State University Dissertations

TMPRSS13, a type II transmembrane serine protease discovered at the turn of the century, has recently been shown to be significantly overexpressed in both breast cancer (BCa) and colorectal cancer (CRC), and to mediate chemoresistance in cell lines from both cancer types. Furthermore, loss of TMPRSS13 in a genetic model of mouse mammary carcinoma significantly reduced tumor burden and growth rate, and increased overall tumor-free survival. Its location on the cell surface as well as its low expression in normal breast and colon make TMPRSS13 an attractive candidate as an oncogenic biomarker and therapeutic target in cancer. However, little is …

Deconstructing Brown Adipocyte Neogenesis In Brown And White Adipose Tissue, Rayanne Burl

Wayne State University Dissertations

Global incidence of Type 2 Diabetes (T2D) has reached epidemic proportions, and increasing evidence indicates that dysfunctional adipose tissue is an important contributor to the pathogenesis of T2D. Expanding brown adipocyte (BA) populations within adipose tissues through adrenergic activation improves energy balance and insulin sensitivity. In order to exploit this remodeling of adipose tissue for therapeutic benefit, we need to understand the mechanisms by which adrenergic signaling expand populations of BAs in vivo. These studies utilized single-cell RNA-sequencing and transgenic mouse models, in combination with single-molecule fluorescence in situ hybridization (smFISH) and immunoistochemical analysis, to study BA neogenesis in vivo. …

Fluorescent Cellular Assays For Kinase Inhibitors, Myar Mohamed

Graduate Research Theses & Dissertations

One of the most successful and fastest growing groups of kinase inhibitors are small molecules that compete with ATP binding. Kinase function is closely related to many diseases, specifically cancer. Kinases within living cells are essential elements in signaling cascades and post-translational modifications. However, actual kinase activity and the efficacy of its inhibitors in living systems are hard to evaluate. A way to assess inhibitor activity is through cellular assays that directly report the inhibitor’s engagement in native environments. Our goal is to develop a simple near-infrared (NIR) fluorescent HTS-compatible cellular assay for kinase inhibitor profiling in native cellular environments. …

Determining The Effects Of Chemical Exposure On Hepatocyte Mitochondrial Networks And Cell Viability, Bethany Eaton

All Master's Theses

Mitochondria are cellular organelles that are becoming more recently studied. One of their main functions is the production of energy through cellular respiration, which is crucial to cell life. However, they are also associated with numerous disease states. It is hypothesized that reactive oxygen species (ROS), largely produced in mitochondria, induce oxidative stress and affect mitochondrial morphology along with cell viability. This study compares chemical exposure of menadione, an ROS producer, and phthalates (plasticizers) on two mouse hepatocyte cell lines to determine the effects they have on mitochondrial morphology and cell viability. Three experiments were performed to analyze the effects …

Biodegradation Of Rubber Particles In Soil: Using Acclimated Bacteria Isolated From Kansas Soil To Degrade Cryogrinds In Slurry, Shane Graham

Williams Honors College, Honors Research Projects

This study investigated the viability of bioremediating rubber cryogrind using enriched indigenous bacteria. To begin the experiment, soils from three highway roadside locations in Kansas, KS 96 and West, KS 400 and 143^rd, and 199^th, were collected and transported to the lab to be studied. An initial soil characterization was run on the soil samples using distilled (DI) water mixture and 0.01 M CaCl₂ to assess conductivity. The soils were tested to gather a baseline of the relationship between pH and conductivity and the impact of its distance from the roadside. Bacteria were isolated from …

Synthesis Of Rna Nucleotides Under Probable Prebiotic Conditions, Ryan Stimson

Williams Honors College, Honors Research Projects

RNA being composed of multiple covalently linked nucleotides is thought to have been a precursor to life circa 4.3-3.8 billion years ago. Non-enzymatically formed adenosine monophosphate (AMP), more specifically, is a vitally important subtopic of the self-assembly of the first RNA sequence. The goal of this study was to synthesize AMP non-enzymatically under benign conditions that are likely to have existed on early Earth. In this experiment, 3’,5’-cAMP was successfully formed using wet-dry cycles at 80°C paired with the minerals zeolite beta, hydroxyapatite, and aerosil 300 in the presence of adenosine, urea, and pyrophosphate. A nuclear magnetic resonance spectrometer was …

The Influence Of Hydrogen Peroxide On The Enrichment Of Fe(Iii) Reducing Bacteria From Acid Mine Drainage, Susami Seth

Williams Honors College, Honors Research Projects

It is hypothesized that the ocean of Europa, a Jupiter moon, hosts bacteria on its oceanic floor. Understanding how Fe(III) reducing bacteria (FeRB) from AMD utilize organic materials within its surrounding environment outlines how FeRB could thrive and tolerate extreme conditions. FeRB are known to tolerate metals and highly reactive oxidants species (ROS), but in this experiment, H₂O₂ was the experimental factor to further test FeRB tolerance. H₂O₂ is a common ROS and is damaging to living material such as proteins, DNA, and RNA. A range of H₂O₂ concentrations were fed …

The Role Of Shoc2 In Embryonic Development, Rebecca G. Norcross

Theses and Dissertations--Molecular and Cellular Biochemistry

The canonical ERK1/2 signaling cascade regulates cellular functions critical in vertebrate embryonic development such as proliferation, apoptosis, differentiation, and migration. Thus, its signals are controlled by a variety of mechanisms. Scaffold proteins are considered central to the mechanisms regulating the transmission of the ERK1/2 signals. Yet, their functions in development nor the molecular mechanisms by which they exert their control are not well understood.

This study focuses on the essential regulator of ERK1/2 signals during development – the scaffold protein Shoc2. Loss of Shoc2 leads to early embryonic lethality in mice and zebrafish. Germline mutations in the shoc2 gene result …

Structural Basis For Reversible Glucan Phosphorylation By Glucan Dikinases And Glucan Phosphatases, Tiantian Chen

Theses and Dissertations--Molecular and Cellular Biochemistry

Plants store glucose in the form of starch, an insoluble macromolecule that is synthesized and degraded diurnally. Glucan phosphatases play a critical role in starch breakdown, working with glucan dikinases in a cyclic phosphorylation and dephosphorylation. Herein, we present a novel glucan phosphatase Like SEX Four3 (LSF3) from Physcomitrella patens. Structural and enzymatic studies demonstrate that LSF3 is a dimeric glucan phosphatase that displays robust specific glucan phosphatase activity. Dimerization is shown to be essential for LSF3 stability and function. Structure-guided bioinformatic analysis shows that LSF3 is found in early land plants and green algae.

Building upon our understanding of …