Biochemistry, Biophysics, and Structural Biology Commons^™

Air-Jet Bioprinting Of Stem Cell-Encapsulated Alginate Micro-Droplets For Organoid Biomanufacturing, Mirabella B. Stump

Electronic Theses and Dissertations

Biomanufactured 3D-organoids show promise for modeling and treating various conditions, particularly insulin-dependent diabetes mellitus (type-1 diabetes). Pancreatic islet organoids serve as sustainable sources of insulin-producing β-cells, potentially restoring insulin regulation in patients and providing a long-term solution for diabetes. Hydrogel droplet printing is an emerging technique in regenerative medicine due to its advantageous tunability and biocompatibility; however, challenges of consistency, quality control, and scalability persist. To address these issues, we developed a novel air-jetting based droplet bioprinting system for the generation of monodispersed alginate micro-droplets. The objective of this project was to incorporate human induced pluripotent stem cells (hiPSCs) into …

Targeting Metabolic Switches And Dna Damage Repair For The Treatment Of Human Diseases, Rasangi Chathurika Kankanam Pathirage

Theses & Dissertations

Tuberculosis and Cancer treatments share common challenges due to prolonged therapy, the necessity of combination therapy and severe side effects. Characterization of novel drug targets and identification of new drugs modulating such targets within the context of multidrug treatments will contribute to overcoming current therapeutic challenges.

Tuberculosis (TB) is one of the challenging diseases to treat due to the persistence of Mycobacterium tuberculosis (Mtb) in the dormant phase. Current TB drugs are more effective toward actively dividing bacteria and less effective toward dormant bacteria. The metabolic transition between actively dividing bacteria and dormant bacteria is driven by pivotal metabolic enzymes …

Characterization Of Trafficking And Metabolic Functions Of The Endocytic Regulator Ehd1 In Ewing Sarcoma, Sukanya Chakraborty

Theses & Dissertations

Ewing sarcoma (EWS) is the second most common bone malignancy in children and adolescents. Despite improvement in survival due to advances in multimodality treatment strategies, patients with metastatic or recurrent disease have very poor outcomes. Overexpression of the EPS15 Homology Domain containing 1 (EHD1) protein has been linked to tumorigenesis but whether its core function as a regulator of intracellular traffic of cell surface receptors plays a role in oncogenesis remains unknown.

Studies presented in this dissertation establish that EHD1 overexpression is a feature of nearly 90% EWS patient tumors with high EHD1 expression specifying shorter patient survival. ShRNA-knockdown and …

Targeting Eif4a Triggers An Interferon Response To Synergize With Chemotherapy And Suppress Triple-Negative Breast Cancer, Na Zhao, Elena B Kabotyanski, Alexander B Saltzman, Anna Malovannaya, Xueying Yuan, Lucas C Reineke, Nadia Lieu, Yang Gao, Diego A Pedroza, Sebastian J Calderon, Alex J Smith, Clark Hamor, Kazem Safari, Sara Savage, Bing Zhang, Jianling Zhou, Luisa M Solis, Susan G Hilsenbeck, Cheng Fan, Charles M Perou, Jeffrey M Rosen

Faculty, Staff and Students Publications

Protein synthesis is frequently dysregulated in cancer and selective inhibition of mRNA translation represents an attractive cancer therapy. Here, we show that therapeutically targeting the RNA helicase eIF4A with zotatifin, the first-in-class eIF4A inhibitor, exerts pleiotropic effects on both tumor cells and the tumor immune microenvironment in a diverse cohort of syngeneic triple-negative breast cancer (TNBC) mouse models. Zotatifin not only suppresses tumor cell proliferation but also directly repolarizes macrophages toward an M1-like phenotype and inhibits neutrophil infiltration, which sensitizes tumors to immune checkpoint blockade. Mechanistic studies revealed that zotatifin reprograms the tumor translational landscape, inhibits the translation of Sox4 …

Role Of Gonadotropin-Releasing Hormone 2 And Its Receptor In Human Reproductive Cancers, Dr. Amy T. Desaulniers, Brett White

School of Veterinary and Biomedical Sciences: Faculty Publications

Gonadotropin-releasing hormone (GnRH1) and its receptor (GnRHR1) drive reproduction by regulating gonadotropins. Another form, GnRH2, and its receptor (GnRHR2), also exist in mammals. In humans, GnRH2 and GnRHR2 genes are present, but coding errors in the GnRHR2 gene are predicted to hinder full-length protein production. Nonetheless, mounting evidence supports the presence of a functional GnRHR2 in humans. GnRH2 and its receptor have been identified throughout the body, including peripheral reproductive tissues like the ovary, uterus, breast, and prostate. In addition, GnRH2 and its receptor have been detected in a wide number of reproductive cancer cells in humans. Notably, GnRH2 analogues …

Mutational Analysis Of The Nitrogenase Carbon Monoxide Protective Protein Cown Reveals That A Conserved C‑Terminal Glutamic Acid Residue Is Necessary For Its Activity, Dustin L. Willard, Joshuah J. Arellano, Mitch Underdahl, Terrence M. Lee, Avinash S. Ramaswamy, Gabriella Fumes, Agatha Kliman, Emily Y. Wong, Cedric P. Owens

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Nitrogenase is the only enzyme that catalyzes the reduction of nitrogen gas into ammonia. Nitrogenase is tightly inhibited by the environmental gas carbon monoxide (CO). Many nitrogen fixing bacteria protect nitrogenase from CO inhibition using the protective protein CowN. This work demonstrates that a conserved glutamic acid residue near the C-terminus of Gluconacetobacter diazotrophicus CowN is necessary for its function. Mutation of the glutamic acid residue abolishes both CowN’s protection against CO inhibition and the ability of CowN to bind to nitrogenase. In contrast, a conserved C-terminal cysteine residue is not important for CO protection by CowN. Overall, this work …

Deep Learning Image Analysis To Isolate And Characterize Different Stages Of S-Phase In Human Cells, Kevin A. Boyd, Rudranil Mitra, John Santerre, Christopher L. Sansam

SMU Data Science Review

Abstract. This research used deep learning for image analysis by isolating and characterizing distinct DNA replication patterns in human cells. By leveraging high-resolution microscopy images of multiple cells stained with 5-Ethynyl-2′-deoxyuridine (EdU), a replication marker, this analysis utilized Convolutional Neural Networks (CNNs) to perform image segmentation and to provide robust and reliable classification results. First multiple cells in a field of focus were identified using a pretrained CNN called Cellpose. After identifying the location of each cell in the image a python script was created to crop out each cell into individual .tif files. After careful annotation, a CNN was …

Using In Silico Tools To Analyze The 5ʹ Untranslated Regions Of The Alcohol Dehydrogenase Gene From Arabidopsis Thaliana And Omega Sequence, Reza Mohammadhassan, Tina Asadishad

Makara Journal of Science

The 5ʹ ends of protein-encoding genes contain 5ʹ untranslated regions (5ʹUTRs), which can effectively participate in regulating gene expression. The 5ʹUTRs of Arabidospis thaliana–derived alcohol dehydrogenase gene (AtADH) and omega (Ω) sequence from tobacco mosaic virus (TMV) are the most effective enhancers in biotechnology. In this study, bioinformatics techniques were employed to analyze the characteristics of the above sequences. After 5ʹUTR sequence collection, the inner ribosome entrance sites; small RNA (sRNA) target sequences; nucleotide contents; and upstream start and stop codons, ORFs, and coding DNA sequences of the Ω sequence and AtADH 5ʹUTR were identified. Moreover, the …

The Potential Of Endophytic Bacteria As The Biocontrol Agents Of Fusarium Proliferatum, Rima Ernia, Nisa Rachmania Mubarik, Lisdar Idwan Sudirman

Makara Journal of Science

Fusarium proliferatum decreases the productivity of shallot (Allium cepa L.). Endophytic bacteria are potential biocontrol agents in controlling the growth of F. proliferatum. This study aimed to select and characterize endophytic bacteria producing bioactive compounds that inhibit the growth of F. proliferatum. The endophytic bacteria used were isolated from the roots, stems, leaves, and soil of shallot plants from healthy and diseased shallot farming fields. The endophytic bacteria were selected using the dual culture method and extracted using ethyl acetate solvent. The results of the 16S rRNA identification suggested that isolate ABP5.2 is similar to Pseudomonas …

Role Of Prmt5 In Ulk1-Mediated Autophagy And Breast Cancer Therapy, Charles Brobbey

MUSC Theses and Dissertations

PRMT5 (Protein arginine methyltransferase 5) is the predominant type II PRMT that monomethylates and symmetrically dimethylates arginine residues of histone and none- histone proteins to regulate diverse cellular processes. PRMT5 overexpression has been implicated in tumorigenesis and other diseases and has gained trac1on as a poten1al an1tumor target with some of its inhibitors being tested in clinical trials. Despite the well- established an1tumor effect of PRMT5 inhibitors, how the efficacy of these inhibitors is regulated is unexplored. We show in this study that autophagy blockage enhances cellular sensi1vity to PRMT5 inhibitor in triple nega1ve breast cancer cells. Both gene1c deple1on …

Increased Coding Potential Of Bovine Herpesvirus 1, Victoria Jefferson

Theses and Dissertations

Bovine respiratory disease (BRD) costs the cattle industry millions of dollars in costs in treatment and loss every year in the United States. A significant pathogen often contributes to BRD is Bovine Herpesvirus 1 (BoHV-1), a double stranded DNA virus with the ability to establish latency in the trigeminal ganglia and neurons. Primary infection with BoHV-1 results in immunosuppression that increases the risk of secondary bacterial infection and pneumonia. Because herpesviruses infect their hosts for life and can be reactivated in times of stress, BoHV-1 can present a recurring risk of BRD. The following research aims to expand the knowledge …

Heterotypic Interaction Of Α-Synuclein And Tdp-43 In Neurodegenerative Diseases, Shailendra Dhakal

Dissertations

Amyloid aggregates of specific proteins form important pathological hallmarks in many neurodegenerative diseases, defining neuronal degeneration and disease onset. Recently, increasing numbers of patients show co-morbidities and exhibit clinical and pathological overlaps between multiple neurodegenerative diseases including α-synucleinopathies and TDP-43 proteinopathies. These overlaps are often accompanied by co-localization of α-synuclein (αS) and TDP-43 enhancing the possibility of direct interactions to generate heterotypic amyloids with distinct cellular consequences. To understand this, we investigate the interaction of α-synuclein (αS) and prion-like domain of TDP-43 (TDP-43 PrLD) in both homogenous and inhomogeneous phases. Firstly, we show that monomeric TDP-43 PrLD and αS interact …

Structural Features Of Hiv-1 Integrase In The Late Stage Of Viral Replication, Tolga Catmakas

Dissertations

HIV-1 integrase (IN) is an essential enzyme for the viral life cycle as it integrates viral genomic material into the host cell genome. In addition to its’ essential catalytic function, IN has another important non-catalytic role where it binds the viral RNA to facilitate successful particle maturation during the viral life cycle. A significant number of IN mutants, addressed as class II IN mutants, show various defects, affecting different steps of the viral life cycle. Class II IN mutants exhibit aberrant morphology where viral ribonucleoprotein particles are mislocalized outside of the capsid core. This phenomenon can be observed in the …

Biophysical Factors Affecting Habitat Suitability For Crassostrea Virginica, Jason D. Tilley

Dissertations

Oyster reefs provide a variety of important ecosystem services. However, the mortality rate of eastern oyster, Crassostrea virginica, the dominant species that produces oyster reefs in the northern Gulf of Mexico, is increasing at an alarming rate due to a variety of abiotic and biological factors. I examined how biophysical factors, including the less-studied fatty acid profiles of the suspended particulate matter on which oysters feed, influenced morphometric condition of C. virginica.

I sampled suspended particulate matter (SPM) and oysters in-situ in the western Mississippi Sound, which historically supported the majority of oyster production in Mississippi waters. Sampling …

Do We Still Need Aspirin In Coronary Artery Disease?, Muhammad Haisum Maqsood, Glenn N Levine, Neal D Kleiman, David Hasdai, Barry F Uretsky, Yochai Birnbaum

Faculty, Staff and Students Publications

Aspirin has for some time been used as a first-line treatment for acute coronary syndromes, including ST-elevation myocardial infarction, for secondary prevention of established coronary disease, and for primary prevention in patients at risk of coronary artery disease. Although aspirin has been in use for decades, the available evidence for its efficacy largely predates the introduction of other drugs, such as statins and P2Y12 inhibitors. Based on recent trials, the recommendation for aspirin use as primary prevention has been downgraded. In addition, P2Y12 inhibitors given as a single antiplatelet therapy have been associated with a lower incidence of bleeding than …

Biomarkers For Heart Failure Prediction And Prevention, Prasanti Alekhya Kotta, Vijay Nambi, Biykem Bozkurt

Faculty, Staff and Students Publications

Heart failure (HF) is a global pandemic affecting over 64 million people worldwide. Its prevalence is on an upward trajectory, with associated increasing healthcare expenditure. Organizations including the American College of Cardiology (ACC) and the American Heart Association (AHA) have identified HF prevention as an important focus. Recently, the ACC/AHA/Heart Failure Society of America (HFSA) Guidelines on heart failure were updated with a new Class IIa, Level of Evidence B recommendation for biomarker-based screening in patients at risk of developing heart failure. In this review, we evaluate the studies that have assessed the various roles and contributions of biomarkers in …

Effects Of Dimerization On The Deacylase Activities Of Human Sirt2., Jie Yang, Nathan I Nicely, Brian P Weiser

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Human sirtuin isoform 2 (SIRT2) is an NAD+-dependent enzyme that functions as a lysine deacetylase and defatty-acylase. Here, we report that SIRT2 readily dimerizes in solution and in cells and that dimerization affects its ability to remove different acyl modifications from substrates. Dimerization of recombinant SIRT2 was revealed with analytical size exclusion chromatography and chemical cross-linking. Dimerized SIRT2 dissociates into monomers upon binding long fatty acylated substrates (decanoyl-, dodecanoyl-, and myristoyl-lysine). However, we did not observe dissociation of dimeric SIRT2 in the presence of acetyl-lysine. Analysis of X-ray crystal structures led us to discover a SIRT2 double mutant (Q142A/E340A) that …

Diaryl Oxazoles As Cleavable Linkers For Drug Discovery Platforms, Elizabeth Taggart

Honors Theses

Within the field of medicine and pharmacology, discovering small molecule or biologic based molecules with therapeutic potential is a difficult task. Current methods involve individually screening hundreds of compounds on a potential target biomolecule, and recent technologies have explored peptide encoded libraries (PELs) as a means of making this screening process more high-throughput. These libraries produce a large number of small molecule drug candidates each conjugated to a unique peptide fragment, functioning as a barcode. Analysis of PELs requires the capture of hit small molecules and the subsequent release of their peptide tags; however, current approaches are limited in their …

Liquid Chromatography Mass Spectrometry Method Development For The Determination Of Β–Defensins In Bovine Milk, Elisha Ogbebor

Masters Theses & Specialist Projects

Bovine mastitis is caused by a wide range of pathogens which results in a substantial economic loss for the dairy cattle livestock industry. β-defensins are a part of the innate immune system and act as the first line of defense against mastitis in bovine. β-defensins (~6- 10kDa) are antimicrobial peptides that contain about 28 to 67 amino acids, the presence of six cysteine residues results in their three disulfide bonds and a β-sheet structure. A few β- defensins have been identified in cows based on the site of occurrence and time of expression in tissue, but not in milk. A …

Analyzing Functional Interactions Of Designed Peptides By Nmr Spectroscopy, Wonsuk Choi

Pharmaceutical Sciences (MS) Theses

The development of small peptide-based therapeutics can be accelerated by the knowledge of relationships between the peptide structure and its functional interactions. Here, we report the analysis of two groups of synthetic peptides designed for two applications – broad bactericidal action and inhibition of protein-protein interactions in human cells. Novel amphiphilic peptides designed for antibacterial application incorporated arginine as cationic amino acids and non-natural amino acids that have aromatic side chains with similar hydrophobic properties as tryptophan. The interaction of lead cyclic peptides and their linear analogs with a phospholipid bilayer mimicking a bacterial membrane was studied using nuclear magnetic …