Molecular Biology Commons^™

The Synthetic Biology Of N2-Fixing Cyanobacteria For Photosynthetic Terpenoid Production, Charles T. Halfmann

Electronic Theses and Dissertations

In the last few decades, concerns over global climate change, energy security, and environmental pollution have been rising. To overcome these challenges, the concept of “-n^th generation” biofuels has emerged as a strategy to convert solar radiation into fuels and bulk industrial chemicals for societal use, while decreasing our consumption of nonrenewable energy sources. Nitrogen-fixing cyanobacteria hold a distinct advantage in biofuel production over plants, given their ability to convert sunlight, air (CO₂ and N₂), and mineralized water to energy-dense carbon molecules, as well as fix atmospheric nitrogen gas into ammonia for metabolism. Engineered cyanobacteria with …

Avoiding Proteolysis During Protein Purification, Barry J. Ryan, Gary T. Henehan

Books/Book Chapters/ Proceedings

All cells contain proteases which hydrolyze the peptide bonds between amino acids in a protein backbone. Typically, proteases are prevented from nonspecific proteolysis by regulation and by their physical separation into different subcellular compartments; however, this segregation is not retained during cell lysis, which is the initial step in any protein isolation procedure. Prevention of proteolysis during protein purification often takes the form of a two-pronged approach; firstly inhibition of proteolysis in situ, followed by the early separation of the protease from the protein of interest via chromatographical purification. Protease inhibitors are routinely used to limit the effect of the …

Progesterone Receptor And Prostaglandins Mediate Luteinizing Hormone-Induced Changes In Messenger Rnas For Adamts Proteases In Theca Cells Of Bovine Periovulatory Follicles, Erin L. Willis, Phillip J. Bridges, Joanne E. Fortune

Animal and Food Sciences Faculty Publications

Little is known about the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family of extracellular proteases in ovarian follicles of non‐rodent species, particularly in theca cells. In the present study, temporal changes in the abundance of mRNA encoding four ADAMTS subtypes and hormonal regulation of mRNA encoding two subtypes were investigated in theca interna cells during the periovulatory period in cattle. Gonadotropin‐releasing hormone (GnRH) was injected into animals to induce a luteinizing hormone (LH)/follicle‐stimulating hormone (FSH) surge, and follicles were obtained at 0 hr post‐GnRH (preovulatory) or at 6, 12, 18, or 24 hr (periovulatory). ADAMTS1, ‐2, …

Characterizing Regulatory Factors Of The Sumoylation System, David Quintanar

Open Access Theses & Dissertations

The effects that influenzaâ??s seasonal epidemics have on human health and the global economy have been clearly noted; while they are indeed very impressive, the impact of influenza pandemics arguably surpass other known infectious agents. Influenza A virus attaches to, enters, and infect cells by releasing its segmented genome which localize to the nucleus then use the hostâ??s cellular machinery to replicate and create viral progeny. The virus is able to hijack transcriptional components as well as to interact with other known and unknown host proteins which ultimately allows for a balance between cell viability and viral propagation. One known …

Nitrosative Stress Sensing In Porphyromonas Gingivalis: Structure And Function Of The Heme Binding Transcriptional Regulator Hcpr, Benjamin R. Belvin

Theses and Dissertations

Porphyromonas gingivalis, a Gram negative anaerobe implicated in the progression of periodontal disease, is capable of surviving and causing infection despite high levels of reactive nitrogen species found in the oral cavity due to its efficient nitrosative stress response. HcpR is an important sensor-regulator that plays a vital step in the initiation of the nitrosative stress response in many Gram negative anaerobic bacteria. We employ a combination of X-ray crystallography, SAXS, resonance Raman spectroscopy, UV-Vis spectroscopy, and molecular biology techniques to better understand this key regulator. Knockout of the hcpR gene in W83 P. gingivalis results in the inability of …

Development And Characterization Of Novel Anti-Bat Monoclonal Antibodies For Studying Bat Immunity, Cailyn Cowan

Legacy Theses & Dissertations (2009 - 2024)

Abstract

Profiling Resistance To P450-Activated Food Carcinogens Using Toxicogenomic Approaches In Budding Yeast, Nicholas Stjohn

Legacy Theses & Dissertations (2009 - 2024)

The human response to environmental carcinogens, some of which require metabolic activation, is highly variable. Factors such as environment, lifestyle, and genetics all influence the rates of exposure to and ultimate bioactivation of these compounds. Genetic factors include mutations to cell-cycle regulation, cell proliferation, and DNA repair genes; however, epidemiological studies may lack significance due to inadequate patient numbers. We used budding yeast as a model organism to determine genetic susceptibility to food-associated carcinogens, including aflatoxin (AFB1) and heterocyclic aromatic amines (HAAs). Budding yeast does not contain P450s that activate these compounds, so expression vectors were induced that contain human …

Altered Lipid Metabolism And Adipocyte Activity Support Her2+ Breast Cancer Progression, Jason Wong

Legacy Theses & Dissertations (2009 - 2024)

Overexpression of HER2 (ERBB2/neu) in breast cancer is an established clinical marker for aggressive disease and increased mortality. HER2+ breast cancers have increased protein levels of Human Epidermal Growth Factor Receptor 2 and overexpression of its coding gene, ERBB2. Many HER2+ tumors feature concomitant co-expression of the Nuclear Receptor subfamily 1, Group D, Member 1 (NR1D1/RevERBα) which regulates adipogenesis and circadian rhythm; the dysregulation of these two processes are known risk factors for breast cancer. HER2+ breast cancer cells have increased lipid synthesis, with evidence suggesting that NR1D1 is responsible for the upregulation of several genes in the de novo …

Structural And Functional Characterization Of An Unusual Camp Responsive Transcription Factor, Cmr, In Tb Complex Mycobacteria, Sridevi Ranganathan

Legacy Theses & Dissertations (2009 - 2024)

Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis in humans, is an intracellular pathogen that infects millions of people every year. Mtb can survive inside the host for extended periods of time by sensing and adapting to the host environmental stressors. Transcriptional gene regulation plays a critical role in this adaptation. This dissertation focuses on understanding the structural and functional aspects of one such transcriptional regulatory unit, Cmr (Rv1675c), in Mtb.

Retinal Disease Modeling And Drug Screening Using Stem Cell Derived Retinal Pigment Epithelium, Janmeet Singh Saini

Legacy Theses & Dissertations (2009 - 2024)

The eye is an intricate organ, possessing sensory receptors in the retina that are involved in visual perception. The retina consists primarily of the neural layer, referred to as the neural retina, and the pigmented layer, referred to as the retinal pigment epithelium (RPE). The neural retina and RPE develop and mature in a coordinated manner, and depend on each other for survival. In a mature healthy retina, the retinal photoreceptor outer segments interdigitate with the RPE monolayer, and they co-exchange key supportive factors. RPE cells are indispensable for the health of the retina as they are involved in a …

A Tale Of Two Regulators : Characterization Of The Novel Transcription Factor Abmr And The Small Non-Coding Rna Mcr11 In Mycobacterium Tuberculosis, Roxanne Candice Girardin

Legacy Theses & Dissertations (2009 - 2024)

Genes of unknown function make up nearly one third of Mtb’s genome (Cole,

Influence Of The Pre-Initiation Complex On Mediator Recruitment In Saccharomyces Cerevisiae, Elisabeth Rose Knoll

Legacy Theses & Dissertations (2009 - 2024)

The Mediator complex plays a central, highly conserved role in eukaryotic transcription by RNA Polymerase II (Pol II) by stimulating the cooperative assembly of a pre-initiation complex (PIC) and recruitment of Pol II for gene activation. Mediator recruitment has generally been ascribed to sequence-specific activators engaging subunits from the tail module which in turn function to recruit the middle and head for complete assembly at the UAS. Mediator subunits of the middle and head then bridge the enhancer to connect with the PIC at the core promoter. It is reported that Mediator recruitment at the UAS preferentially occurs at SAGA-dependent, …

The Role Of The Mediator Transcriptional Co-Activator Complex And Promoter Dependence In Ty1 Retrotransposition In Saccharomyces Cerevisiae, Alicia Salinero

Legacy Theses & Dissertations (2009 - 2024)

Retrotransposons are mobile genetic elements that replicate via an RNA intermediary and constitute a significant portion of most eukaryotic genomes. Saccharomyces cerevisiae has been invaluable to retrotransposon research due to the presence of an active retroelement known as Ty1. The mobility of Ty1 is regulated both positively and negatively by numerous host factors, including several subunits of the Mediator transcriptional co-activator complex. The Mediator core complex is organized into genetically and structurally defined head, middle, and tail modules, along with a transiently associated kinase module. We show that with the exception of the kinase module, deletion of non-essential subunits from …

Effects Of Antibiotic Treatment On The Expression Of Hepatic And Intestinal Cytochrome P450, Bruno Pereira De Carvalho

Legacy Theses & Dissertations (2009 - 2024)

Expression of metabolic enzymes Cytochrome P450 (CYP) is highly affected by drugs, diseases, age and gender. The Intestinal microflora has been suggested to play a role in regulating CYP expression and antibiotic treatments would lead to changes in level and composition of microbiota in mouse gut. This study aims to analyze CYP expression changes in the liver and small intestine resulted from the reduction of intestinal microflora by antibiotics. Impacts on bile acid signaling were also analyzed for a better comprehension of the mechanisms involved in this modulation. Female C57BL/6J mice (9- to 13-week old) were treated with ampicillin (AMP) …

Differential Precipitation And Solubilisation Of Proteins, Barry J. Ryan, Gemma K. Kinsella

Books/Book Chapters/ Proceedings

Differential protein precipitation is a rapid and economical step in protein purification and is based on exploiting the inherent physicochemical properties of the polypeptide. Precipitation of recombinant proteins, lysed from the host cell, is commonly used to concentrate the protein of choice before further polishing steps with more selective purification columns (e.g., His-Tag, Size Exclusion, etc.). Recombinant proteins can also precipitate naturally as inclusion bodies due to various influences during overexpression in the host cell. Although this phenomenon permits easier initial separation from native proteins, these inclusion bodies must carefully be differentially solubilized so as to reform functional, correctly folded …

Biochemical And Molecular Assessment Of Toxicity Of Primaquine Metabolites On Erythrocytes, Jagrati Jain

Electronic Theses and Dissertations

The 8-aminoquinoline (8AQ) antimalarial drug primaquine (PQ) is the only drug for prevention of malaria relapse. Moreover, PQ also has gametocytocidal activity against Plasmodium falciparum. However, clinical use of PQ has been limited due to its hemolytic toxicity, especially in glucose-6-phosphate dehydrogenase deficient (G6PDd) individuals. Phenolic and quinone metabolites generated via cytochrome P450-dependent pathways appear to be responsible for hemolytic effects of PQ. However, the mechanism for the hemolytic toxicity of PQ is still poorly understood. To explore the mechanism, targets, and pathways for toxicity of PQ, normal and G6PDd human erythrocytes were treated with the potential hemotoxic metabolites of …

Nucleic Acid Clamp-Mediated Transcriptional And Translational Modulation Of Oncogenes Via The Stabilization Of G-Quadruplexes, Taisen Hao

Electronic Theses and Dissertations

G-quadruplexes (G4s) are non-canonical secondary nucleic acid structures that exit in various biologically important regions within a cell, such as the promoters of DNA, 5’-Untranslated regions (UTR) of mRNA and telomeres. These secondary structures tend to cluster around 1 kb from transcriptional start sites across all human chromosomes in addition to at telomeric regions. Extensive efforts from many research groups have been dedicated to targeting G4s in oncogenic promoters, telomeres, and 5’-UTRs with traditional small molecules. However, most small molecules recognizing multiple G4s raising potential issues in terms of utilizing these small molecules clinically. Therefore, we developed a novel nucleic …

Patholigical And Prognostic Role Of Mdig In Pancreatic Cancer, Srinivas Ashok Kumar

Wayne State University Theses

Pancreatic cancer is a highly aggressive malignant disease having very limited therapeutic options that ultimately results in its poor prognosis. It is still elusive on the etiology and tumorigenic mechanisms of pancreatic cancer. In the present report, we provide evidence showing involvement of the mineral dust-induced gene (mdig) in the pathogenesis and prognosis of the pancreatic cancer. Using immunohistochemistry approach on human pancreatic cancer tissue microarray, we found differential expression of mdig in pancreatic adenocarcinoma and normal pancreas. Based on the staining intensities of mdig in these tissue samples, we found that 12% of the cancer tissues were strongly positive …

The Effect Of Acetylation Of Cytochrome C On Its Functions In Prostate Cancer, Viktoriia Bazylianska

Wayne State University Theses

Prostate cancer is the second leading cause of cancer death among men in America. The progression of cancer goes along with the Warburg effect, a metabolic switch from depending primarily on mitochondrial respiration to glycolysis. In addition, cancer cells manage to evade apoptosis. Cell signaling, via posttranslational modifications (PTMs), is one of the most important means of regulation, and most commonly dysregulated in cancer. In prostate cancer, androgen signaling plays a crucial role in driving cell proliferation.

Mammalian Cytochrome c (Cytc) is a multifunctional protein involved in cellular life and death decision. It is an essential component of the electron …

Human Cytomegalovirus Cytoplasmic Virion Assembly Complex: Structure In Vivo And Role Of Pul103 In Its Biogenesis, Ma Christina Raye Lim

Wayne State University Theses

Human Cytomegalovirus (HCMV) is a linear, double stranded DNA virus that causes severe disease in the immunocompromised, and is one of the common cause of congenital disease. Antivirals that are currently available for treatment target the DNA replication of the virus cycle, and are highly toxic. Finding new drug targets, such as proteins responsible for virion assembly and egress, would help to alleviate the disease burden.

HCMV remodels the host cell to form a structure called the cytoplasmic virion assembly complex (cVAC), a site of virion maturation and egress. The first objective of this work is to study the structure …

Fam129b Phosphorylation And Its Effect On Membrane Localization In Confluent Hela Cells, Lakshmi Thompil Somasekharan

Wayne State University Theses

Phosphorylation and de-phosphorylation of many proteins is a key regulator of cellular life. It maintains cellular activity through an array of signaling pathways like cell division, proliferation and growth. However, Overexpression or mutations by the constitutive activation of phosphorylation machinery disrupt the balance in the cell, driving the inappropriate activation or deactivation of the cellular processes it controls. FAM129B is a protein whose activity is partly maintained by phosphorylation and dephosphorylation at the six serine residues at the C-terminal. FAM129B is expressed highly in many forms of cancer and its main function is to suppress apoptosis and enhances cancer cell …

Elucidating Structure, Function, And Small Molecular Interactions Of Human Immunodeficiency Virus And Chikungunya Virus, Kristin Nicole Slater

Wayne State University Theses

Abstract HIV-1:

Human immunodeficiency virus-1 (HIV-1) is a widespread, incurable retrovirus known to cause

immunodeficiency and a shortened life span. Despite successful treatment methods, HIV-1

frequently mutates, resulting in antiviral resistance. Many therapies target the HIV-1 protease

(PR), which is responsible for cleaving the viral polyprotein essential for its life cycle. HIV-1 PR

often evades treatment by way of mutations and less commonly through residue insertions. We

have identified a clinical isolate with a five residue insertion between residues 28 and 29.

Through molecular dynamics simulations we analyzed the protease protein structure and

determined that the residue insertion created a …

Primate Proteomic Composition Of Seminal Plasma And Prostate-Specific Transglutaminase Activity In Relation To Sexual Selection., Amanda M.C. Zielen

Electronic Theses and Dissertations

Humans (Homo sapiens), chimpanzees (Pan troglodytes), and gorillas (Gorilla gorilla) have diverse mating systems with varying levels of sperm competition. Several seminal plasma genes have been claimed to evolve under positive selection, while others are altered or lost. This study aims to identify biologically relevant differences among seminal plasma proteomes of primates in relation to mating systems and previous genomic studies. Seminal plasma from three individuals of each species were run in triplicate in shotgun liquid chromatography – tandem mass spectrometry (LC-MS/MS) and confirmed with Western blots. Over 7,000 peptides were identified across all …

The Localization And Function Of Novel Tetrahymena Thermophila Cytoskeletal Genes Bbc29 And Bbc39, Emily K. Moore, Nicole C. Zanolli

Undergraduate Research Symposium Posters

Ciliary function is known to play an important role in many human conditions, including chronic sinus and pulmonary diseases and problems with infertility. Cilia are cytoskeletal structures that protrude from the cell body to facilitate movement. Ciliary structure is conserved throughout eukaryotes, from unicellular to multicellular organisms, including humans. A clear understanding the proteins that compose cilia and how they interact with one another will increase our knowledge about important cytoskeletal elements. Because cilia are difficult to study in multicellular organisms, the unicellular eukaryote Tetrahymena thermophila serves as a useful model for the study of cytoskeletal genes, due to their …

Micro-Spectroscopy Of Bio-Assemblies At The Single Cell Level, Jeslin Kera

Honors Undergraduate Theses

In this thesis, we investigate biological molecules on a micron scale in the ultraviolet spectral region through the non-destructive confocal absorption microscopy. The setup involves a combination of confocal microscope with a UV light excitation beam to measure the optical absorption spectra with spatial resolution of 1.4 μm in the lateral and 3.6 μm in the axial direction. Confocal absorption microscopy has the benefits of requiring no labels and only low light intensity for excitation while providing a strong signal from the contrast generated by the attenuation of propagating light due to absorption. This enables spatially resolved measurements of single …

Investigation Of The Mechanism Of Action For Mithramycin And The Biosynthesis Of L-Rednose In Saquayamycins, Stevi Weidenbach

Theses and Dissertations--Pharmacy

Natural products continue to be a major chemical lead matter for drug discovery due to their diverse chemical structures and bioactivities. Clinically significant natural products include anti-cancer and anti-infective compounds and while many more of these compounds show promising bioactivity, their clinical relevance is often limited by toxicity or poor solubility. Combinatorial biosynthesis can be employed to modify existing chemical scaffolds towards reducing these limitations. To fully take advantage of these biochemical tools, it is important to understand the biosynthesis and mechanism of action of the molecules.

Saccharides in glycosylated natural products provide specific interactions with cellular targets and are …

Evolution Of Equine Arteritis Virus During Persistent Infection In The Reproductive Tract Of The Stallion And The Male Donkey, Bora Nam

Theses and Dissertations--Veterinary Science

Equine arteritis virus (EAV) establishes persistent infection in the stallion reproductive tract, and the carrier stallion continues to shed virus in semen for weeks to years or lifelong. The objective of this study was to elucidate the intra-host evolution of EAV during persistent infection in stallions. Seven EAV seronegative stallions were experimentally infected with EAV KY84 strain and followed for 726 days post-infection, and sequential clinical samples including semen were collected for virus isolation and next-generation sequencing (NGS). In addition, archived sequential semen samples from two stallions that were naturally infected with EAV KY84 for a long-period (up to 10 …

Steroidogenesis In The Green Anole Lizard Brain And Gonad, Christine Peek

All Graduate Theses, Dissertations, and Other Capstone Projects

Seasonally breeding animals reproduce during certain times of the year and, subsequently, behaviors, steroid hormone levels, and brain morphology change. The green anole lizard (Anolis carolinensis) is an excellent model to study the regulation of steroid hormone production because they have distinct hormonal and behavioral differences between sexes and seasons. As in other vertebrates, steroidogenesis in anoles is under the control of the hypothalamus-pituitary-gonadal (HPG) axis. We tested the hypothesis that natural variations in steroid hormone levels between sexes and seasons are mediated within the brain and gonad by examining four genes involved in steroidogenesis: StAR, Cyp17α1, HSD17β3, and Cyp19α1. …

Iron Metabolism Genes In Browsing And Grazing Rhinoceroses: Implications For Iron Overload Disorder, Lorien Salyer

Undergraduate Honors Thesis Projects

Iron overload disorder is a serious condition that affects many animals of conservation interest, including rhinoceroses. Iron overload disorder is only found in browsing rhinos (African black, Diceros bicornis, and Sumatran, Dicerorhinus sumatrensis) but not in grazing species (African white, Ceratotherium simum, and greater one-horned, Rhinoceros unicornis). Iron overload is connected with many of the other health issues seen in captive browsing rhinoceroses, so it is vitally important that the iron metabolism process is studied to improve the existing husbandry procedures of these critically endangered animals. The objective of this study was to characterize genes related to …

Ligands Of Therapeutic Utility For The Liver X Receptors., Rajesh Komati, Dominick Spadoni, Shilong Zheng, Jayalakshmi Sridhar

Faculty and Staff Publications

Liver X receptors (LXRs) have been increasingly recognized as a potential therapeutic target to treat pathological conditions ranging from vascular and metabolic diseases, neurological degeneration, to cancers that are driven by lipid metabolism. Amidst intensifying efforts to discover ligands that act through LXRs to achieve the sought-after pharmacological outcomes, several lead compounds are already being tested in clinical trials for a variety of disease interventions. While more potent and selective LXR ligands continue to emerge from screening of small molecule libraries, rational design, and empirical medicinal chemistry approaches, challenges remain in minimizing undesirable effects of LXR activation on lipid metabolism. …